Publications by category
Journal articles
Young W (In Press). Exposure Worry: the Psychological Impact of Perceived. Ionizing Radiation Exposure in British Nuclear Test Veterans.
International Journal of Environmental Research and Public HealthAbstract:
Exposure Worry: the Psychological Impact of Perceived. Ionizing Radiation Exposure in British Nuclear Test Veterans
Potential psychological issues faced by British nuclear test veterans have been under-researched. This study assessed the prevalence of clinically relevant anxiety in British nuclear test veterans and aimed to explore experiences of worry and the broader psychological impact of the British nuclear weapons testing programme. The Geriatric Anxiety Inventory (Short-Form) was com-pleted by 89 British nuclear test veterans (33.7% met the criteria for clinically relevant anxiety). Nineteen veterans then participated in semi-structured interviews. Thematic analysis of the data generated three themes. The first theme highlighted how worry was relevant only in a few cases (four) generally regarding their grandchildren’s health, but the guilt in those who perceive re-sponsibility for family health conditions also appeared to be a pertinent issue. The second theme highlighted the anger towards authorities resulting from perceived negligence and deception. The third theme highlighted the relevance of how certain life events across the life course in-fluence the potential psychological impact. This study suggests that guilt must be considered in (potentially) exposed individuals whose family members experience health conditions, which may exacerbate distress. It also suggests the importance that authorities ensure transparency when dealing with any radiological exposure scenario to reduce the potential for anger.
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Wang A, Sieber J, Young W, Tsaneva-Atanasova K (In Press). Time series analysis and modelling of the freezing of gait phenomenon.
SIAM Journal on Applied Dynamical SystemsAbstract:
Time series analysis and modelling of the freezing of gait phenomenon
Freezing of Gait (FOG) is one of the most debilitating symptoms of Parkinson's Disease and is associated with falls and loss of independence. The patho-physiological mechanisms underpinning FOG are currently poorly understood. In this paper we combine time series analysis and mathematical modelling to study the FOG phenomenon's dynamics. We focus on the transition from stepping in place into freezing and treat this phenomenon in the context of an escape from an oscillatory attractor into an equilibrium attractor state. We extract a discrete-time discrete-space Markov chain from experimental data and divide its state space into communicating classes to identify the transition into freezing. This allows us to develop a methodology for computationally estimating the time to freezing as well as the phase along the oscillatory (stepping) cycle of a patient experiencing Freezing Episodes (FE). The developed methodology is general and could be applied to any time series featuring transitions between different dynamic regimes including time series data from forward walking in people with FOG.
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Lamb SE, Williams G, Young W (2024). The science of falls and how to prevent them.
Nat Med,
30(1), 35-36.
Author URL.
Raffegeau TE, Young WR, Fino PC, Williams AM (2023). A Perspective on Using Virtual Reality to Incorporate the Affective Context of Everyday Falls into Fall Prevention. JMIR Aging, 6
Siragy T, Russo Y, Young W, Lamb SE (2023). Comparison of over-ground and treadmill perturbations for simulation of real-world slips and trips: a systematic review.
Gait Posture,
100, 201-209.
Abstract:
Comparison of over-ground and treadmill perturbations for simulation of real-world slips and trips: a systematic review.
BACKGROUND: Trips and slips increase fall risk for young and older adults. To examine recovery responses, studies utilized treadmill and/or over-ground methods to simulate real-world perturbations. However, differences in the recovery response between treadmill and over-ground perturbations remain unexamined. RESEARCH QUESTION: to assess the current literature on the reactive recovery responses between over-ground- and split-belt treadmill trips and slips as well as the effect of aging on these responses. METHODS: PubMed, Medline, Web of Science, SCOPUS, and Cochrane databases were searched for publications examining trips and slips in healthy young, healthy older adults, and older adults who fall. Included articles were in English, full-text accessible, and biomechanically quantified the reactive recovery responses for slips and trips during either over-ground or split-belt treadmill protocols. The initial database search yielded 1075 articles and 31 articles were included after title, abstract, and full-text screening. RESULTS: for slips, 7 articles utilized lubricated surfaces while 5 articles used treadmills. Further, 3 studies examined differences between older and younger adults. For trips, 9 articles utilized obstacles and 7 used treadmills. Further, 4 articles examined differences between older and young adults and 1 article only examined older adults during over-ground trips. For both perturbations, treadmill and over-ground protocols demonstrated similar anteroposterior destabilization on the center of mass. In the mediolateral direction, over-ground slips consistently found a lateral destabilization while treadmill articles did not examine this direction. Foot placement recovery responses varied less for both perturbation directions on a treadmill compared to over-ground. SIGNIFICANCE: Although treadmill and over-ground perturbations destabilize the center of mass similarly, the recovery response to these perturbations were different on treadmills. Specifically, recovery responses were more consistent for both slips and trips on treadmills. As older adults have difficulty in perturbation recovery scaling, treadmills may be limited in their ability to investigate the variety of aging impairments on perturbation recovery responses.
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Rose DC, Poliakoff E, Young WR, Phillips M (2023). Music Moves Me in More Ways Than One: an Online Survey Investigating the Everyday Use of Music among People with Parkinson's.
Music and Science,
6Abstract:
Music Moves Me in More Ways Than One: an Online Survey Investigating the Everyday Use of Music among People with Parkinson's
Background: Music has been used in interventions designed for people with Parkinson's (PwP) either to engage mechanisms involved in phenomena such as sensorimotor synchronization or as an integral part of the activity (e.g. dance). However, little research has been conducted concerning what music PwP use in everyday life and how and why this might differ based on situation/context. Methods: We used an online survey to investigate what music PwP listen to, for which perceived reasons, and in which situations. In addition to demographic and Parkinson's-specific questions, we included standardized measures of quality of life, music and dance sophistication and bespoke items to explore music use. Results: the sample (N = 217, age range 20–88 years, Mean = 65.2, SD = 8.45) included 109 females (50%); 64% of participants reported a mild impact of Parkinson's on Activities of Daily Living. The top three uses of music were Aesthetic Appreciation (98%), Relaxation (92%), and Motivation (90%). The least popular category was using music for walking (36%). The duration of attentive listening was significantly higher for those who reported using music for managing their feelings than those who did not (p
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Raffegeau TE, Clark M, Fawver B, Engel BT, Young WR, Williams AM, Lohse KR, Fino PC (2023). The effect of mobility-related anxiety on walking across the lifespan: a virtual reality simulation study.
Exp Brain Res,
241(7), 1757-1768.
Abstract:
The effect of mobility-related anxiety on walking across the lifespan: a virtual reality simulation study.
Older adults who report a fear of falling are more likely to subsequently fall, yet, some gait anxiety-related alterations may protect balance. We examined the effect of age on walking in anxiety-inducing virtual reality (VR) settings. We predicted a high elevation-related postural threat would impair gait in older age, and differences in cognitive and physical function would relate to the observed effects. Altogether, 24 adults (age (y) = 49.2 (18.7), 13 women) walked on a 2.2-m walkway at self-selected and fast speeds at low (ground) and high (15 m) VR elevation. Self-reported cognitive and somatic anxiety and mental effort were greater at high elevations (all p
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Author URL.
Ellmers TJ, Wilson MR, Kal EC, Young WR (2023). The perceived control model of falling: developing a unified framework to understand and assess maladaptive fear of falling.
Age Ageing,
52(7).
Abstract:
The perceived control model of falling: developing a unified framework to understand and assess maladaptive fear of falling.
BACKGROUND: fear of falling is common in older adults and can have a profound influence on a variety of behaviours that increase fall risk. However, fear of falling can also have potentially positive outcomes for certain individuals. Without progressing our understanding of mechanisms underlying these contrasting outcomes, it is difficult to clinically manage fear of falling. METHODS: this paper first summarises recent findings on the topic of fear of falling, balance and fall risk-including work highlighting the protective effects of fear. Specific focus is placed on describing how fear of falling influences perceptual, cognitive and motor process in ways that might either increase or reduce fall risk. Finally, it reports the development and validation of a new clinical tool that can be used to assess the maladaptive components of fear of falling. RESULTS: we present a new conceptual framework-the Perceived Control Model of Falling-that describes specific mechanisms through which fear of falling can influence fall risk. The key conceptual advance is the identification of perceived control over situations that threaten one's balance as the crucial factor mediating the relationship between fear and increased fall risk. The new 4-item scale that we develop-the Updated Perceived Control over Falling Scale (UP-COF)-is a valid and reliable tool to clinically assess perceived control. CONCLUSION: this new conceptualisation and tool (UP-COF) allows clinicians to identify individuals for whom fear of falling is likely to increase fall risk, and target specific underlying maladaptive processes such as low perceived control.
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Poliakoff E, Bek J, Phillips M, Young WR, Rose DC (2023). Vividness and Use of Imagery Related to Music and Movement in People with Parkinson's: a Mixed-methods Survey Study.
Music and Science,
6Abstract:
Vividness and Use of Imagery Related to Music and Movement in People with Parkinson's: a Mixed-methods Survey Study
Parkinson's disease affects multiple aspects of movement, impacting significantly on everyday tasks. Music is used in interventions for people with Parkinson's, either to pace movements, or as an integral element of activities such as dance. This study explored self-reported vividness of two forms of imagery – motor imagery evoked by music and auditory (including musical) imagery – in people with Parkinson's, and whether and how they use these types of imagery in everyday life. Participants (N = 199) completed: (i) vividness ratings of visual and kinesthetic music-evoked motor imagery, (ii) vividness ratings of auditory imagery, and (iii) ratings and open questions about their everyday use of these types of imagery. While most participants reported experiencing music-evoked motor imagery (with more vivid visual than kinesthetic motor imagery),
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Alenezi S, Morgan-Trimmer S, Hulbert S, Young W, Goodwin VA (2023). “It's a lot more complicated than it seems”: physiotherapists' experiences of using compensation strategies in people with Parkinson's.
Frontiers in Rehabilitation Sciences,
4Abstract:
“It's a lot more complicated than it seems”: physiotherapists' experiences of using compensation strategies in people with Parkinson's
BackgroundGait disturbances often result in functional limitations in daily activities and negatively impact the quality of life in people with Parkinson's disease. Physiotherapists often employ compensation strategies in an attempt to improve patients' walking. However, little is known about physiotherapists' experiences in this regard. We evaluated how physiotherapists adopt compensation strategies and what they draw on to inform their clinical decision-making.MethodsWe carried out semi-structured online interviews with 13 physiotherapists with current or recent experience working with people with Parkinson's disease in the United Kingdom. Interviews were digitally recorded and transcribed verbatim. Thematic analysis was utilized.ResultsTwo main themes were developed from the data. The first theme, optimizing compensation strategies through personalized care, shows how physiotherapists accounted for the individual needs and characteristics of people with Parkinson's, which resulted in them individually tailoring compensation strategies. The second theme, delivering compensation strategies effectively, considers the available support and perceived challenges with work settings and experience that impact physiotherapists' ability to deliver compensation strategies.DiscussionAlthough physiotherapists strived to optimize compensation strategies, there was a lack of formal training in this area, and their knowledge was primarily acquired from peers. Furthermore, a lack of specific knowledge on Parkinson's can impact physiotherapists’ confidence in maintaining person-centered rehabilitation. However, the question that remains to be answered is what accessible training could address the knowledge–practice gap to contribute to the delivery of better-personalized care for people with Parkinson's.
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Kal EC, Young WR, Ellmers TJ (2022). Balance capacity influences the effects of conscious movement processing on postural control in older adults.
Human Movement Science,
82Abstract:
Balance capacity influences the effects of conscious movement processing on postural control in older adults
Older adults rely increasingly on conscious processes to control balance. While this could be in response to age-related declines in balance capacity, it is unclear whether such strategy is adaptive or not. We investigated whether balance capacity modified the effects of conscious movement processing (CMP) on postural control in older adults. Forty-seven older adults (Mage = 74.8, range = 61–88) completed 60-s, narrow-stance balance trials on a force platform, under conditions designed to increase (high-CMP; through movement-monitoring instructions) or reduce conscious processing (low-CMP; distraction task). Balance capacity was operationalised as a composite score of Berg Balance Scale and Timed-up-and-Go. Balance capacity influenced the effects of the CMP manipulation on mediolateral sway amplitude (p =. 023). Specifically, it positively associated with sway amplitude during the high-CMP condition (β = 0.273), but not low-CMP condition (β = −0.060). In other words, higher balance capacity was associated with increased sway during high-CMP, confirming our hypothesis that CMP does not uniformly negatively impact balance performance. Rather, CMP was maladaptive for those with better balance. Results also indicated that older adults' balance capacity influenced the degree to which they could engage conscious or automatic postural control processes. Specifically, we found that, overall, participants showed reduced mediolateral sway frequency and complexity for the high-CMP vs. low-CMP condition (p's ≤ 0.018), indicating reduced automaticity of balance (as expected). However, these effects were significantly attenuated as balance capacity reduced (i.e. smaller changes in those with lower balance capacity, p's < 0.010). Hence, the ability to readily shift between conscious and automatic modes of postural control seems more constrained as balance becomes worse. Overall, these findings suggest clinicians need to consider older adults' balance capacity when using providing instructions or feedback likely to influence CMP within rehabilitation settings.
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Raffegeau TE, Fawver B, Clark M, Engel BT, Young WR, Williams AM, Lohse KR, Fino PC (2022). Corrigendum to “The feasibility of using virtual reality to induce mobility-related anxiety during turning” [Gait & Posture 77 (2020) 6–13, (Gait & Posture (2020) 77(6–13) (S0966636220300072), (10.1016/j.gaitpost.2020.01.006)).
Gait and Posture,
95Abstract:
Corrigendum to “The feasibility of using virtual reality to induce mobility-related anxiety during turning” [Gait & Posture 77 (2020) 6–13, (Gait & Posture (2020) 77(6–13) (S0966636220300072), (10.1016/j.gaitpost.2020.01.006))
The authors regret that editors were incorrectly listed as authors in a citation in our original publication. Instead, citation number 1 should read: [1] Adkin, A.L. Carpenter, M.G. 2018. New insights on emotional contributions to human postural control. Front. Neurol. 9, 789. https://doi.org/10.3389/fneur.2018.00789 the authors sincerely apologise for any inconvenience caused.
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Rose DC, Poliakoff E, Hadley R, Guérin SMR, Phillips M, Young WR (2022). Levelling the Playing Field: the Role of Workshops to Explore How People with Parkinson's Use Music for Mood and Movement Management as Part of a Patient and Public Involvement Strategy.
Front Rehabil Sci,
3Abstract:
Levelling the Playing Field: the Role of Workshops to Explore How People with Parkinson's Use Music for Mood and Movement Management as Part of a Patient and Public Involvement Strategy.
From a humanistic perspective, participatory processes in research find support on both ethical and moral grounds. In practical terms however, it is often difficult to establish protocols that best honour (i.e. elicit, capture, and integrate) the opinions of individuals and groups that represent the various specific stakeholders (e.g. from allied health, scientific, and academic disciplines) needed to investigate complex phenomena. Here, we describe a consultation process (funded by Parkinson's UK) devised to explore use of music among people with Parkinson's in relation to potential applications to enhance quality of life. People with Parkinson's were paired with researchers in order to discuss music on an equal footing so as to enable participant empowerment. We describe outcomes that demonstrate avenues of success as a result of this approach and additional insights gained through these processes in the hope of informing future practise. It has been our experience that researchers must establish a balance between (a) ensuring methodological rigour within an appropriate framework, and (b) facilitating informal "playtime" that develops connectivity between participants and enables both creative thinking and reflexive practise amongst stakeholders. We encourage researchers not to underestimate "playtime" as an important vehicle to foster this social interactivity and fuel the good will required to conduct inclusive and relevant research.
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Author URL.
Ellmers T, Wilson M, Norris M, Young W (2022). Protective or harmful? a qualitative exploration of older people’s perceptions of worries about falling. Age and Ageing
Ellmers TJ, Wilson MR, Kal EC, Young WR (2022). Standing up to threats: Translating the two-system model of fear to balance control in older adults. Experimental Gerontology, 158, 111647-111647.
Kal EC, Ellmers TJ, Fielding AE, Hardeman L, Coito J, Joyce L, Young WR (2022). Weighting for the Beat: Using a Dance Cue to Facilitate Turning in People with Parkinson's Disease and Freezing of Gait.
J Parkinsons Dis,
12(4), 1353-1358.
Abstract:
Weighting for the Beat: Using a Dance Cue to Facilitate Turning in People with Parkinson's Disease and Freezing of Gait.
Freezing of gait (FOG) can severely compromise daily functioning in people with Parkinson's disease. Inability to initiate a step from FOG is likely underpinned, at least in part, by a deficient preparatory weight-shift. Conscious attempts to weight-shift in preparation to step can improve success of initiating forward steps following FOG. However, FOG often occurs during turning, where weight-shifting is more complex and risk of falling is higher. We explored the effectiveness of a dance-based ('cha-cha') weight-shifting strategy to re-initiate stepping following FOG during turning. Results suggest that this simple movement strategy can enhance turning steps following FOG, without compromising safety.
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Author URL.
Collett G, Martin W, Young WR, Anderson RM (2022). “Is that a coincidence?”: Exploring health perceptions and the causal attributions of physical health conditions in British nuclear test veterans. SSM - Qualitative Research in Health, 2, 100127-100127.
Cocks AJ, Young WR, Ellmers TJ, Jackson RC, Williams AM (2021). Concern about falling is associated with segmental control when turning in older adults.
Gait Posture,
88, 105-108.
Abstract:
Concern about falling is associated with segmental control when turning in older adults.
BACKGROUND: Healthy young adults typically exhibit a progressive 'top-down' reorientation of body segments (i.e. head, trunk, then pelvis) during turning. This behaviour is less evident in older adults at risk of falling, who often reduce angular displacement between body segments during turns. The potential functional and psychological contributors to this so-called 'en-bloc' turning strategy are not yet understood. RESEARCH QUESTION: Are there associations between concern about falling and variables representing en-bloc turning (i.e. increased coupling between body segments)? METHODS: Twenty-one older adults were assessed while turning during an adaptive walking task. We collected data from markers forming the head, trunk, and pelvis segments, while gait velocity throughout the turn was calculated from a sternum marker. We correlated several variables with concern about falling alone, as well as while controlling for functional balance ability. RESULTS: Correlation analyses revealed that concern about falling was related to en-bloc turning strategies and slower gait velocity throughout the turn, when analysed independently of functional balance. When controlling for balance ability, en-bloc turning strategies between the head and trunk, as well as the head and pelvis, remained significantly associated with concern about falling. SIGNIFICANCE: Findings offer an insight into the potential role that psychological characteristics may have in determining older adults' turning behaviour and associated risk of falling.
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Author URL.
Mak TCT, Young WR, Wong TWL (2021). Conscious Control of Gait Increases with Task Difficulty and can be Mitigated by External Focus Instruction. Experimental Aging Research, 47(3), 288-301.
Young W, Ellmers TJ (2021). Translating Attentional Control Theory to Applied Psychological Eye Tracking Research.
Abstract:
Translating Attentional Control Theory to Applied Psychological Eye Tracking Research
This chapter will describe how eye tracking outcomes can be used to evaluate psychological processes, particularly in applied contexts (e.g. clinical anxiety disorders, elite motor performance and rehabilitation settings). Our discussion will focus primarily on the influence of emotion on two key aspects of attentional processing related to Attentional Control Theory: i) attentional bias for threatening stimuli, and ii) processing (in)efficiency. We present key metrics than can be used to infer these processes and describe that previous management of outcome measures can be allocated into two categories: transferred and retrofitted. This content is primarily aimed at readers thinking about using eye-tracking in the context of psychological research and practice; to help them design their task(s) and select appropriate outcome measures in order to avoid potential confounds.
Abstract.
Ellmers T, Cocks A, Kal E, Young W (2020). Conscious movement processing, fall-related anxiety, and the visuomotor control of locomotion in older adults. Journal of Gerontology Series B: Psychological Sciences and Social Sciences
Ellmers T, Kal E, Young W (2020). Consciously processing balance leads to distorted perceptions of instability in older adults. Journal of Neurology
Parakkal Unni M, Menon PP, Livi L, Wilson MR, Young WR, Bronte-Stewart HM, Tsaneva-Atanasova K (2020). Data-Driven Prediction of Freezing of Gait Events from Stepping Data.
Frontiers in Medical Technology,
2, 581264-581264.
Abstract:
Data-Driven Prediction of Freezing of Gait Events from Stepping Data
Freezing of gait (FoG) is typically a symptom of advanced Parkinson’s disease (PD) that negatively influences the quality of life and is often resistant to pharmacological interventions. Novel treatment options that make use of auditory or sensory cues might be optimized by prediction of freezing events. These predictions might help to trigger external sensory cues—shown to improve walking performance—when behavior is changed in a manner indicative of an impending freeze (i.e. when the user needs it the most), rather than delivering cue information continuously. A data-driven approach is proposed for predicting freezing events using Random Forrest (RF), Neural Network (NN), and Naive Bayes (NB) classifiers. Vertical forces, sampled at 100 Hz from a force platform were collected from 9 PD subjects as they stepped in place until they at least had one freezing episode or for 90 s. The F1 scores of RF/NN/NB algorithms were computed for different IL (input to the machine learning algorithm), and GL (how early the freezing event is predicted). A significant negative correlation between the F1 scores and GL, highlighting the difficulty of early detection is found. The IL that maximized the F1 score is approximately equal to 1.13 s. This indicates that the physiological (and therefore neurological) changes leading to freezing take effect at-least one step before the freezing incident. Our algorithm has the potential to support the development of devices to detect and then potentially prevent freezing events in people with Parkinson’s which might occur if left uncorrected.
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Ellmers TJ, Cocks AJ, Young WR (2020). Evidence of a Link Between Fall-Related Anxiety and High-Risk Patterns of Visual Search in Older Adults During Adaptive Locomotion.
J Gerontol a Biol Sci Med Sci,
75(5), 961-967.
Abstract:
Evidence of a Link Between Fall-Related Anxiety and High-Risk Patterns of Visual Search in Older Adults During Adaptive Locomotion.
BACKGROUND: Older adults deemed to be at a high risk of falling will often display visual search behaviors likely to impair movement planning when negotiating environmental hazards. It has been proposed that these behaviors may be underpinned by fall-related anxiety. Thus, the aim of this study was to explore the effects of fall-related anxiety on visual search and stepping behaviors during adaptive gait. METHODS: Forty-four community-dwelling older adults (mean age = 74.61; standard deviation = 6.83) walked along a path and stepped into two raised targets. All participants completed walks at ground level, whereas participants deemed to be at a low risk of falling (n = 24) also completed walks under conditions designed to induce fall-related anxiety (walkway elevated 0.6 m). Participants' movement kinematics and gaze behavior were measured. RESULTS: During ground trials, "high-risk" participants visually prioritized the immediate walkway areas 1-2 steps ahead, at the expense of previewing future stepping constraints. This reduced planning appeared to negatively affect safety, with greater stepping errors observed for future constraints. When completing walks on the elevated walkway, "low-risk" participants similarly prioritized immediate walkway areas, at the expense of planning future stepping actions. These behaviors were associated with greater attention directed toward consciously processing walking movements. CONCLUSIONS: These findings provide evidence of a link between heightened fall-related anxiety and "high-risk" visual search behaviors associated with greater stepping errors. This information enhances our understanding of why high-risk older adults are less able to safely navigate environmental constraints.
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Kal EC, Young WR, Ellmers TJ (2020). Face masks, vision, and risk of falls.
BMJ,
371 Author URL.
Ellmers T, Maslivec A, Young W (2020). Fear of falling alters anticipatory postural control during cued gait initiation. Neuroscience
Young W, Ellmers T, Kinrade N, Cossar J, Cocks A (2020). Re-evaluating the measurement and influence of conscious movement processing on gait performance in older adults: development of the Gait-Specific Attentional Profile. Gait and Posture
Ellmers T, Kal E, Richardson J, Young W (2020). Short-latency inhibition mitigates the relationship between conscious movement processing and overly cautious gait. Age and Ageing
Raffegeau T, Fawver B, Young W, Williams AM, Lohse K, Fino P (2020). The direction of postural threat alters balance control when standing at virtual elevation. Experimental Brain Research
Raffegeau TE, Fawver B, Clark M, Engel BT, Young WR, Williams AM, Lohse KR, Fino PC (2020). The feasibility of using virtual reality to induce mobility-related anxiety during turning. Gait & Posture, 77, 6-13.
Collett G, Craenen K, Young W, Gilhooly M, Anderson R (2020). The psychological consequences of (perceived) ionizing radiation exposure: a review on its role in radiation-induced cognitive dysfunction. International Journal of Radiation Biology
Mak TCT, Young WR, Wong TWL (2020). The role of reinvestment in conservative gait in older adults. Experimental Gerontology, 133, 110855-110855.
Hardeman LES, Kal EC, Young WR, van der Kamp J, Ellmers TJ (2020). Visuomotor control of walking in Parkinson’s disease: Exploring possible links between conscious movement processing and freezing of gait. Behavioural Brain Research, 395, 112837-112837.
Maslivec A, Fielding A, Wilson M, Norris M, Young W (2020). ‘Recoupling’ the attentional and motor control of preparatory postural adjustments to overcome Freezing of Gait in Parkinson’s. Journal of NeuroEngineering and Rehabilitation, 17
Ellmers TJ, Cocks AJ, Young WR (2019). Exploring attentional focus of older adult fallers during heightened postural threat.
Psychological ResearchAbstract:
Exploring attentional focus of older adult fallers during heightened postural threat
© 2019, the Author(s). Objectives: Threats to balance, and subsequent increases in fall-related anxiety, can disrupt attentional processing during gait in older adults, leading to behavioral adaptations which may increase fall risk. However, limited research has investigated what changes in attention occur to contribute to these disruptions. The aim of this research was to describe changes in attention that occur during gait when older adults’ balance is threatened, while exploring how previous fall history and trait movement reinvestment (conscious monitoring and control of movement) also influence attention. Methods: Forty older adults reported where they focus their attention when walking during two scenarios: (1) when they are relaxed and there is little risk of falling, and; (2) when their balance is threatened and they are anxious of falling. Results: During the high-threat condition, participants reported greater attention towards movement processes, threats to balance, worries/disturbing thoughts and self-regulatory strategies, with less attention directed towards task-irrelevant thoughts. However, fall history influenced attentional focus, with fallers directing greater attention towards worries/disturbing thoughts. Contrary to predictions, trait movement reinvestment was not associated with attention directed towards movement processes. Discussion: As processing worries/disturbing thoughts will likely reduce attentional resources available for effective postural control, we highlight this as one potential area to target interventions aimed at reducing the likelihood of repeated falling.
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Chan DCL, Wong TWL, Zhu FF, Lam CC, Young W, Capio CM, Masters RSW (2019). Investigating changes in real-time conscious postural processing by older adults during different stance positions using electroencephalography coherence. Experimental Aging Research
Amini A, Banitsas K, Young WR (2019). Kinect4FOG: monitoring and improving mobility in people with Parkinson's using a novel system incorporating the Microsoft Kinect v2.
Disabil Rehabil Assist Technol,
14(6), 566-573.
Abstract:
Kinect4FOG: monitoring and improving mobility in people with Parkinson's using a novel system incorporating the Microsoft Kinect v2.
Parkinson's is a neurodegenerative condition associated with several motor symptoms including tremors and slowness of movement. Freezing of gait (FOG); the sensation of one's feet being "glued" to the floor, is one of the most debilitating symptoms associated with advanced Parkinson's. FOG not only contributes to falls and related injuries, but also compromises quality of life as people often avoid engaging in functional daily activities both inside and outside the home. In the current study, we describe a novel system designed to detect FOG and falling in people with Parkinson's (PwP) as well as monitoring and improving their mobility using laser-based visual cues cast by an automated laser system. The system utilizes a RGB-D sensor based on Microsoft Kinect v2 and a laser casting system consisting of two servo motors and an Arduino microcontroller. This system was evaluated by 15 PwP with FOG. Here, we present details of the system along with a summary of feedback provided by PwP. Despite limitations regarding its outdoor use, feedback was very positive in terms of domestic usability and convenience, where 12/15 PwP showed interest in installing and using the system at their homes. Implications for Rehabilitation Providing an automatic and remotely manageable monitoring system for PwP gait analysis and fall detection. Providing an automatic, unobtrusive and dynamic visual cue system for PwP based on laser line projection. Gathering feedback from PwP about the practical usage of the implemented system through focus group events.
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Chow VWK, Ellmers TJ, Young WR, Mak TCT, Wong TWL (2019). Revisiting the relationship between internal focus and balance control in young and older adults.
Frontiers in Neurology,
10(JAN).
Abstract:
Revisiting the relationship between internal focus and balance control in young and older adults
© 2019 Chow, Ellmers, Young, Mak and Wong. Research highlights the detrimental effect that directing too much conscious attention toward movement can have on postural control. While this concept has received support from many studies, recent evidence demonstrates that this principle does not always translate to aging clinical populations. Given the increasing clinical interest in this topic, the current study evaluated if the original notion (that an internal focus results in compromised balance performance) is upheld in young and older adults during a challenging balance task where we are able to objectively corroborate changes in attentional focus; using an electroencephalography (EEG) method previously identified as an objective indicator of conscious movement control. This method assesses the neural coherence, or “communication,” between T3 (verbal-analytical) and Fz (motor-planning) regions of the brain. Thirty-nine young and 40 older adults performed a challenging balance task while holding a 2-meter pole under two randomized conditions: Baseline and Internal focus of attention (directing attention internally toward movement production). Results showed that young adults demonstrated increased EEG T3-Fz coherence in conjunction with increased sway path during the Internal focus condition. However, no significant differences were observed in older adults between conditions for any measure. The current study provides supporting evidence for the detrimental effect that adopting an Internal focus can have on postural control-especially in populations able to govern these processes in a relatively “automatic” manner (e.g. young adults). However, this work illustrates that such observations may not readily translate between populations and are not robust to age-related changes. Further work is necessary to examine mechanisms underlying this clear translational issue.
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Mak TCT, Young W, Lam WK, Tse ACY, Wong TWL (2019). The Role of Attentional Focus on Walking Efficiency among Older Fallers and Non-fallers. Age and Ageing
Ellmers TJ, Young WR (2019). The influence of anxiety and attentional focus on visual search during adaptive gait. Journal of Experimental Psychology: Human Perception and Performance, 45(6), 697-714.
Doumas M, Morsanyi K, Young WR (2018). Cognitively and socially induced stress affects postural control.
Exp Brain Res,
236(1), 305-314.
Abstract:
Cognitively and socially induced stress affects postural control.
Postural control is an adaptive process that can be affected by many aspects of human behavior, including emotional contexts. The main emotional contexts that affect postural control are postural threat and passive viewing of aversive or threatening images, both of which produce a reduction in postural sway. The aim of the present study was to assess whether similar stress-related changes in postural sway can be observed using stress induced by social evaluative threat (SET) while performing arithmetic tasks. Twelve young adults performed an arithmetic and a postural control task separately, concurrently, and concurrently with added time pressure in the arithmetic task. In the final condition, participants were given negative feedback about their performance in the arithmetic task and performed it again while being observed (SET condition). Results showed that stress increased linearly with task demand. Postural sway and reaction times were not affected by the first two conditions; however, when time pressure was introduced, reaction times became faster and sway amplitude increased. Finally, introduction of SET caused the predicted reduction in postural sway and an increase in reaction times relative to the time pressure condition. Our results suggest that stress induced using a combination of arithmetic tasks and social evaluative threat leads to systematic changes in postural control. The paradigm developed in the present study would be very useful in assessing interactions between cognition, stress, and postural control in the context of postural instability and falls in older adults.
Abstract.
Author URL.
Ellmers TJ, Young WR (2018). Conscious motor control impairs attentional processing efficiency during precision stepping. Gait & Posture, 63, 58-62.
Mak TCT, Young WR, Chan DCL, Wong TWL (2018). Gait Stability in Older Adults During Level-Ground Walking: the Attentional Focus Approach. The Journals of Gerontology: Series B
Ellmers TJ, Paraskevopoulos IT, Williams AM, Young WR (2018). Recalibrating disparities in perceived and actual balance abilities in older adults: a mixed-methods evaluation of a novel exergaming intervention.
J Neuroeng Rehabil,
15(1).
Abstract:
Recalibrating disparities in perceived and actual balance abilities in older adults: a mixed-methods evaluation of a novel exergaming intervention.
BACKGROUND: Published reports suggest a disparity between perceived and actual balance abilities, a trait associated with increased fall-risk in older adults. We investigate whether it is possible to 'recalibrate' these disparities using a novel gaming intervention. METHODS: We recruited 26 older adults for a 4-week intervention in which they participated in 8-sessions using a novel gaming intervention designed to provide explicit, augmented feedback related to postural control. Measures of perceived balance abilities (Falls Efficacy Scale-International) and actual postural control (limits of stability) were assessed pre- and post-intervention. We used focus groups to elicit the opinions of participants about how the game may have influenced balance abilities and confidence. RESULTS: a stronger alignment was observed between postural control and perceived balance capabilities post-intervention (i.e. significant correlations between Falls Efficacy Scale-International scores and limits of stability which were not present pre-intervention). Also, significant improvements in measures of postural control were observed, with these improvements confined to the aspects of postural control for which the exergame provided explicit, augmented feedback. Qualitative data revealed that the intervention made participants more "aware" of their balance abilities. CONCLUSIONS: Our results demonstrate that it is possible to recalibrate the perceptions of older adults relating to their balance abilities through a targeted, short-term intervention. We propose that the post-intervention improvements in postural control may have been, in part, the result of this recalibration; with altered perceptions leading to changes in balance performance. Findings support the application of novel interventions aimed at addressing the psychological factors associated with elderly falls.
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Author URL.
Uiga L, Capio CM, Ryu D, Young WR, Wilson MR, Wong TWL, Tse ACY, Masters RSW (2018). The Role of Movement-Specific Reinvestment in Visuomotor Control of Walking by Older Adults.
Journals of Gerontology, Series B,
75(2), 282-292.
Abstract:
The Role of Movement-Specific Reinvestment in Visuomotor Control of Walking by Older Adults
Objectives: the aim of this study was to examine the association between conscious monitoring and control of movements (i.e. movement specific reinvestment) and visuo-motor control during walking by older adults. Method: the Movement Specific Reinvestment Scale (MSRS; Masters, Eves, & Maxwell, 2005) was administered to ninety-two community-dwelling older adults, aged 65-81 years, who were required to walk along a 4.8-meter walkway and step on the middle of a target as accurately as possible. Participants' movement kinematics and gaze behavior were measured during approach to the target and when stepping on it. Results: High scores on the MSRS were associated with prolonged stance and double support times during approach to the stepping target, and less accurate foot placement when stepping on the target. No associations between MSRS and gaze behavior were observed. Discussion: Older adults with a high propensity for movement specific reinvestment seem to need more time to "plan" future stepping movements, yet show worse stepping accuracy than older adults with a low propensity for movement specific reinvestment. Future research should examine whether older adults with a higher propensity for reinvestment are more likely to display movement errors that lead to falling.
Abstract.
Keune PM, Young WR, Paraskevopoulos IT, Hansen S, Muenssinger J, Oschmann P, Müller R (2017). Measuring standing balance in multiple sclerosis: Further progress towards an automatic and reliable method in clinical practice. Journal of the Neurological Sciences, 379, 157-162.
Ellmers TJ, Machado G, Wong TW-L, Zhu F, Williams AM, Young WR (2016). A validation of neural co-activation as a measure of attentional focus in a postural task.
Gait Posture,
50, 229-231.
Abstract:
A validation of neural co-activation as a measure of attentional focus in a postural task.
Postural threat can induce conscious involvement in movement control. This internal focus has been implicated in compromising attentional processing efficiency during postural control, leading to behavioral adaptations that might increase the risk of falling in the elderly. It is suggested that electroencephalography (EEG) coherence, or 'communication', between T3 (verbal-analytical) and Fz (motor-planning) regions may provide an objective measure of internal focus in learned movement skills. However, it is currently unknown whether this experimental technique can be applied to the control of gait and posture; skills which develop early in life, without the use of declarative knowledge/explicit verbal cues to guide performance. We validate the utility of the EEG T3-Fz coherence analysis in a postural task. A total of 24 young adults produced small voluntary swaying movements in medial-lateral or anterior-posterior direction under conditions that directed their attentional focus either internally or externally. Although EEG coherence was sensitive to voluntary changes in attentional focus, the lack of observed between-group (High/Low-trait-reinvestment) difference in coherence may suggest that younger adults cannot be assumed to utilize explicit verbal cues to control voluntary postural sway unless explicitly instructed to do so. As a result, while these results indicate that EEG T3-Fz is a valid technique for assessing attentional focus in postural tasks, our data do not support the clinical application of this method of analysis in providing an objective indication of trait-reinvestment in tasks involving voluntary postural sway.
Abstract.
Author URL.
Young WR, Shreve L, Quinn EJ, Craig C, Bronte-Stewart H (2016). Auditory cueing in Parkinson's patients with freezing of gait. What matters most: Action-relevance or cue-continuity?.
Neuropsychologia,
87, 54-62.
Abstract:
Auditory cueing in Parkinson's patients with freezing of gait. What matters most: Action-relevance or cue-continuity?
Gait disturbances are a common feature of Parkinson's disease, one of the most severe being freezing of gait. Sensory cueing is a common method used to facilitate stepping in people with Parkinson's. Recent work has shown that, compared to walking to a metronome, Parkinson's patients without freezing of gait (nFOG) showed reduced gait variability when imitating recorded sounds of footsteps made on gravel. However, it is not known if these benefits are realised through the continuity of the acoustic information or the action-relevance. Furthermore, no study has examined if these benefits extend to PD with freezing of gait. We prepared four different auditory cues (varying in action-relevance and acoustic continuity) and asked 19 Parkinson's patients (10 nFOG, 9 with freezing of gait (FOG)) to step in place to each cue. Results showed a superiority of action-relevant cues (regardless of cue-continuity) for inducing reductions in Step coefficient of variation (CV). Acoustic continuity was associated with a significant reduction in Swing CV. Neither cue-continuity nor action-relevance was independently sufficient to increase the time spent stepping before freezing. However, combining both attributes in the same cue did yield significant improvements. This study demonstrates the potential of using action-sounds as sensory cues for Parkinson's patients with freezing of gait. We suggest that the improvements shown might be considered audio-motor 'priming' (i.e. listening to the sounds of footsteps will engage sensorimotor circuitry relevant to the production of that same action, thus effectively bypassing the defective basal ganglia).
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Author URL.
Young WR, Olonilua M, Masters RSW, Dimitriadis S, Mark Williams A (2016). Examining links between anxiety, reinvestment and walking when talking by older adults during adaptive gait.
Exp Brain Res,
234(1), 161-172.
Abstract:
Examining links between anxiety, reinvestment and walking when talking by older adults during adaptive gait.
Falls by older adults often result in reduced quality of life and debilitating fear of further falls. Stopping walking when talking (SWWT) is a significant predictor of future falls by older adults and is thought to reflect age-related increases in attentional demands of walking. We examine whether SWWT is associated with use of explicit movement cues during locomotion, and evaluate if conscious control (i.e. movement specific reinvestment) is causally linked to fall-related anxiety during a complex walking task. We observed whether twenty-four older adults stopped walking when talking when asked a question during an adaptive gait task. After certain trials, participants completed a visuospatial recall task regarding walkway features, or answered questions about their movements during the walk. In a subsequent experimental condition, participants completed the walking task under conditions of raised postural threat. Compared to a control group, participants who SWWT reported higher scores for aspects of reinvestment relating to conscious motor processing but not movement self-consciousness. The higher scores for conscious motor processing were preserved when scores representing cognitive function were included as a covariate. There were no group differences in measures of general cognitive function, visuospatial working memory or balance confidence. However, the SWWT group reported higher scores on a test of external awareness when walking, indicating allocation of attention away from task-relevant environmental features. Under conditions of increased threat, participants self-reported significantly greater state anxiety and reinvestment and displayed more accurate responses about their movements during the task. SWWT is not associated solely with age-related cognitive decline or generic increases in age-related attentional demands of walking. SWWT may be caused by competition for phonological resources of working memory associated with consciously processing motor actions and appears to be causally linked with fall-related anxiety and increased vigilance.
Abstract.
Author URL.
Ellmers TJ, Cocks AJ, Doumas M, Williams AM, Young WR (2016). Gazing into thin air: the dual-task costs of movement planning and execution during adaptive gait.
PLoS ONE,
11(11).
Abstract:
Gazing into thin air: the dual-task costs of movement planning and execution during adaptive gait
© 2016 Ellmers et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. We examined the effect of increased cognitive load on visual search behavior and measures of gait performance during locomotion. Also, we investigated how personality traits, specifically the propensity to consciously control or monitor movements (trait movement 'reinvestment'), impacted the ability to maintain effective gaze under conditions of cognitive load. Healthy young adults traversed a novel adaptive walking path while performing a secondary serial subtraction task. Performance was assessed using correct responses to the cognitive task, gaze behavior, stepping accuracy, and time to complete the walking task. When walking while simultaneously carrying out the secondary serial subtraction task, participants visually fixated on task-irrelevant areas 'outside' the walking path more often and for longer durations of time, and fixated on task-relevant areas 'inside' the walkway for shorter durations. These changes were most pronounced in high-trait-reinvesters. We speculate that reinvestment-related processes placed an additional cognitive demand upon working memory. These increased task-irrelevant 'outside' fixations were accompanied by slower completion rates on the walking task and greater gross stepping errors. Findings suggest that attention is important for the maintenance of effective gaze behaviors, supporting previous claims that the maladaptive changes in visual search observed in high-risk older adults may be a consequence of inefficiencies in attentional processing. Identifying the underlying attentional processes that disrupt effective gaze behaviour during locomotion is an essential step in the development of rehabilitation, with this information allowing for the emergence of interventions that reduce the risk of falling.
Abstract.
Whyatt C, Merriman NA, Young WR, Newell FN, Craig C (2015). A Wii Bit of Fun: a Novel Platform to Deliver Effective Balance Training to Older Adults.
Games Health J,
4(6), 423-433.
Abstract:
A Wii Bit of Fun: a Novel Platform to Deliver Effective Balance Training to Older Adults.
BACKGROUND: Falls and fall-related injuries are symptomatic of an aging population. This study aimed to design, develop, and deliver a novel method of balance training, using an interactive game-based system to promote engagement, with the inclusion of older adults at both high and low risk of experiencing a fall. STUDY DESIGN: Eighty-two older adults (65 years of age and older) were recruited from sheltered accommodation and local activity groups. Forty volunteers were randomly selected and received 5 weeks of balance game training (5 males, 35 females; mean, 77.18 ± 6.59 years), whereas the remaining control participants recorded levels of physical activity (20 males, 22 females; mean, 76.62 ± 7.28 years). The effect of balance game training was measured on levels of functional balance and balance confidence in individuals with and without quantifiable balance impairments. RESULTS: Balance game training had a significant effect on levels of functional balance and balance confidence (P
Abstract.
Author URL.
Keune PM, Cocks AJ, Young WR, Burschka JM, Hansen S, Hofstadt-van Oy U, Oschmann P, Muenssinger J (2015). Dynamic walking features and improved walking performance in multiple sclerosis patients treated with fampridine (4-aminopyridine). BMC Neurology, 15(1).
Young WR, Mark Williams A (2015). How fear of falling can increase fall-risk in older adults: Applying psychological theory to practical observations. Gait & Posture, 41(1), 7-12.
Young W, Williams AM (2015). The multifaceted nature of fear of falling must be considered. The Journal of Physiology
Young WR, Rodger MWM, Craig CM (2014). Auditory observation of stepping actions can cue both spatial and temporal components of gait in Parkinson's disease patients.
Neuropsychologia,
57(1), 140-153.
Abstract:
Auditory observation of stepping actions can cue both spatial and temporal components of gait in Parkinson's disease patients
Objectives: a common behavioural symptom of Parkinson[U+05F3]s disease (PD) is reduced step length (SL). Whilst sensory cueing strategies can be effective in increasing SL and reducing gait variability, current cueing strategies conveying spatial or temporal information are generally confined to the use of either visual or auditory cue modalities, respectively. We describe a novel cueing strategy using ecologically-valid 'action-related' sounds (footsteps on gravel) that convey both spatial and temporal parameters of a specific action within a single cue. Methods: the current study used a real-time imitation task to examine whether PD affects the ability to re-enact changes in spatial characteristics of stepping actions, based solely on auditory information. In a second experimental session, these procedures were repeated using synthesized sounds derived from recordings of the kinetic interactions between the foot and walking surface. A third experimental session examined whether adaptations observed when participants walked to action-sounds were preserved when participants imagined either real recorded or synthesized sounds. Results: Whilst healthy control participants were able to re-enact significant changes in SL in all cue conditions, these adaptations, in conjunction with reduced variability of SL were only observed in the PD group when walking to, or imagining the recorded sounds. Conclusions: the findings show that while recordings of stepping sounds convey action information to allow PD patients to re-enact and imagine spatial characteristics of gait, synthesis of sounds purely from gait kinetics is insufficient to evoke similar changes in behaviour, perhaps indicating that PD patients have a higher threshold to cue sensorimotor resonant responses. © 2014.
Abstract.
Bienkiewicz MMN, Young WR, Craig CM (2014). BALLS TO THE WALL: HOW ACOUSTIC INFORMATION FROM a BALL IN MOTION GUIDES INTERCEPTIVE MOVEMENT IN PEOPLE WITH PARKINSON'S DISEASE.
NEUROSCIENCE,
275, 508-518.
Author URL.
Rodger MWM, Young WR, Craig CM (2014). Synthesis of walking sounds for alleviating gait disturbances in Parkinson's disease.
IEEE Transactions on Neural Systems and Rehabilitation Engineering,
22(3), 543-548.
Abstract:
Synthesis of walking sounds for alleviating gait disturbances in Parkinson's disease
Managing gait disturbances in people with Parkinson's disease is a pressing challenge, as symptoms can contribute to injury and morbidity through an increased risk of falls. While drug-based interventions have limited efficacy in alleviating gait impairments, certain nonpharmacological methods, such as cueing, can also induce transient improvements to gait. The approach adopted here is to use computationally-generated sounds to help guide and improve walking actions. The first method described uses recordings of force data taken from the steps of a healthy adult which in turn were used to synthesize realistic gravel-footstep sounds that represented different spatio-temporal parameters of gait, such as step duration and step length. The second method described involves a novel method of sonifying, in real time, the swing phase of gait using real-time motion-capture data to control a sound synthesis engine. Both approaches explore how simple but rich auditory representations of action based events can be used by people with Parkinson's to guide and improve the quality of their walking, reducing the risk of falls and injury. Studies with Parkinson's disease patients are reported which show positive results for both techniques in reducing step length variability. Potential future directions for how these sound approaches can be used to manage gait disturbances in Parkinson's are also discussed. © 2014 IEEE.
Abstract.
Young WR (2014). We need a balanced perspective in Wii-search. Gait & Posture, 39(4), 1156-1157.
Young W, Rodger M, Craig CM (2013). Perceiving and reenacting spatiotemporal characteristics of walking sounds.
Journal of Experimental Psychology: Human Perception and Performance,
39(2), 464-476.
Abstract:
Perceiving and reenacting spatiotemporal characteristics of walking sounds
Many studies have examined the processes involved in recognizing types of human action through sound, but little is known about whether the physical characteristics of an action (such as kinetic and kinematic parameters) can be perceived and imitated from sound. Twelve young healthy adults listened to recordings of footsteps on a gravel path taken from walks of different stride lengths (SL) and cadences. In 1 protocol, participants performed a real-time reenactment of the walking action depicted in a sound sample. Second, participants listened to 2 different sound samples and discriminated differences in SL. In a 2nd experiment, these procedures were repeated using synthesized sounds derived from the kinetic interactions between the foot and walking surface. A 3rd experiment examined the influence of altered cadence on participants' ability to discriminate changes in SL. Participants significantly adapted their own SL and cadence according to those depicted in both real and synthesized sounds (p <. 01). However, although participants accurately discriminated between large changes in SL, these perceptions were heavily influenced by temporal factors, that is, when cadence changed between samples. These findings show that spatial attributes of action sounds can be both mimicked and discriminated, even when only basic kinetic interactions present within the action are specified. © 2012 American Psychological Association.
Abstract.
Bieńkiewicz MMN, Rodger MWM, Young WR, Craig CM (2013). Time to get a move on: Overcoming bradykinetic movement in Parkinson's disease with artificial sensory guidance generated from biological motion.
Behavioural Brain Research,
253, 113-120.
Abstract:
Time to get a move on: Overcoming bradykinetic movement in Parkinson's disease with artificial sensory guidance generated from biological motion
Paradoxical kinesia describes the motor improvement in Parkinson's disease (PD) triggered by the presence of external sensory information relevant for the movement. This phenomenon has been puzzling scientists for over 60 years, both in neurological and motor control research, with the underpinning mechanism still being the subject of fierce debate. In this paper we present novel evidence supporting the idea that the key to understanding paradoxical kinesia lies in both spatial and temporal information conveyed by the cues and the coupling between perception and action. We tested a group of 7 idiopathic PD patients in an upper limb mediolateral movement task. Movements were performed with and without a visual point light display, travelling at 3 different speeds. The dynamic information presented in the visual point light display depicted three different movement speeds of the same amplitude performed by a healthy adult. The displays were tested and validated on a group of neurologically healthy participants before being tested on the PD group. Our data show that the temporal aspects of the movement (kinematics) in PD can be moderated by the prescribed temporal information presented in a dynamic environmental cue. Patients demonstrated a significant improvement in terms of movement time and peak velocity when executing movement in accordance with the information afforded by the point light display, compared to when the movement of the same amplitude and direction was performed without the display. In all patients we observed the effect of paradoxical kinesia, with a strong relationship between the perceptual information prescribed by the biological motion display and the observed motor performance of the patients. © 2013 Elsevier B.V.
Abstract.
Young WR, Hollands MA (2012). Evidence for age-related decline in visuomotor function and reactive stepping adjustments.
Gait Posture,
36(3), 477-481.
Abstract:
Evidence for age-related decline in visuomotor function and reactive stepping adjustments.
This study investigated age-related and fall-risk-related differences in the ability to make visually guided reactive stepping adjustments during locomotion. Participants were asked to walk towards and step accurately onto a visual target which, during the step towards it, moved to an unpredictable location at an unpredictable time. We measured lower limb kinematics and eye movement characteristics of young adults and two groups of older adults deemed to be either at a low- or high-risk of falling. High-risk older adults produced significant deviations in foot trajectory with latencies of ∼300 ms, compared to 280 ms in low-risk older adults and ∼200 ms in young adults. Furthermore, high-risk older adults were unable to generate adjustments with the same magnitude and consistency as low-risk older adults and young adults. Saccadic reaction latencies also were doubled in high-risk older adults compared to young. Analysis of covariance showed that the significant between group differences in final foot placement error could be accounted for by differences in saccadic response times. We propose that age-related delays in visuomotor processing times may disrupt the timing and magnitude of stepping adjustments, possibly contributing to an increased likelihood of falls.
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Author URL.
Young WR, Wing AM, Hollands MA (2012). Influences of state anxiety on gaze behavior and stepping accuracy in older adults during adaptive locomotion.
J Gerontol B Psychol Sci Soc Sci,
67(1), 43-51.
Abstract:
Influences of state anxiety on gaze behavior and stepping accuracy in older adults during adaptive locomotion.
OBJECTIVES: Older adults deemed to be at a high risk of falling transfer their gaze from a stepping target earlier than their low-risk counterparts. The extent of premature gaze transfer increases with task complexity and is associated with a decline in stepping accuracy. This study tests the hypothesis that increased anxiety about upcoming obstacles is associated with (a) premature transfers of gaze toward obstacles (i.e. looking away from a target box prior to completing the step on it in order to fixate future constraints in the walkway) and (b) reduced stepping accuracy on the target in older adults. METHODS: High-risk (9) and low-risk (8) older adult participants walked a 10-m pathway containing a stepping target area followed by various arrangements of obstacles, which varied with each trial. Anxiety, eye movements, and movement kinematics were measured. RESULTS: Progressively increasing task complexity resulted in associated statistically significant increases in measures of anxiety, extent of early gaze transfer, and stepping inaccuracies in the high-risk group. DISCUSSION: These results provide evidence that increased anxiety about environmental hazards is related to suboptimal visual sampling behavior which, in turn, negatively influences stepping performance, potentially contributing to increased falls risk in older adults.
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Author URL.
Young WR, Hollands MA (2012). Newly acquired fear of falling leads to altered eye movement patterns and reduced stepping safety: a case study.
PLoS One,
7(11).
Abstract:
Newly acquired fear of falling leads to altered eye movement patterns and reduced stepping safety: a case study.
This opportune case study describes visual and stepping behaviours of an 87 year old female (P8), both prior to, and following two falls. Before falling, when asked to walk along a path containing two stepping guides positioned before and after an obstacle, P8 generally visually fixated the first stepping guide until after foot contact inside it. However, after falling P8 consistently looked away from the stepping guide before completing the step into it in order to fixate the upcoming obstacle in her path. The timing of gaze redirection away from the target (in relation to foot contact inside it) correlated with absolute stepping error. No differences in eyesight, cognitive function, or balance were found between pre- and post-fall recordings. However, P8 did report large increases in fall-related anxiety and reduced balance confidence, supporting previously suggested links between anxiety/increased fear or falling and maladaptive visual/stepping behaviours. The results represent a novel insight into how psychological and related behavioural factors can change in older adults following a fall, and provide a possible partial rationalisation for why recent fallers are more likely to fall again in the following 12 months. These findings highlight novel possibilities for falls prevention and rehabilitation.
Abstract.
Author URL.
Merriman NA, Whyatt C, Setti A, Gillian N, Young W, Ferguson S, Craig C, Newell FN (2012). The effect of balance training on audio–visual integration in older adults. Multisensory Research, 25(0), 155-155.
Young W, Ferguson S, Brault S, Craig C (2011). Assessing and training standing balance in older adults: a novel approach using the 'Nintendo Wii' Balance Board.
Gait Posture,
33(2), 303-305.
Abstract:
Assessing and training standing balance in older adults: a novel approach using the 'Nintendo Wii' Balance Board.
Older adults, deemed to be at a high risk of falling, are often unable to participate in dynamic exercises due to physical constraints and/or a fear of falling. Using the Nintendo 'Wii Balance Board' (WBB) (Nintendo, Kyoto, Japan), we have developed an interface that allows a user to accurately calculate a participant's centre of pressure (COP) and incorporate it into a virtual environment to create bespoke diagnostic or training programmes that exploit real-time visual feedback of current COP position. This platform allows researchers to design, control and validate tasks that both train and test balance function. This technology provides a safe, adaptable and low-cost balance training/testing solution for older adults, particularly those at high-risk of falling.
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Author URL.
Thøgersen-Ntoumani C, Barkoukis V, Grano C, Lucidi F, Lindwall M, Liukkonen J, Raudsepp L, Young W (2011). Health and well-being profiles of older European adults. European Journal of Ageing, 8(2), 75-85.
Young WR, Hollands MA (2010). Can telling older adults where to look reduce falls? Evidence for a causal link between inappropriate visual sampling and suboptimal stepping performance.
Exp Brain Res,
204(1), 103-113.
Abstract:
Can telling older adults where to look reduce falls? Evidence for a causal link between inappropriate visual sampling and suboptimal stepping performance.
Older adults at high risk of falling look away prematurely from targets they are stepping on in order to fixate future constraints in their walking path. This gaze behaviour is associated with decreased stepping accuracy and precision. The aims of the present study were to determine whether this apparently maladaptive gaze behaviour can be altered through intervention and to measure any corresponding improvements in stepping performance. Sixteen older adults, randomly placed into a control or intervention group, walked a 10-m path placing their feet into targets while their gaze direction and lower limb kinematics were measured. On average, both groups looked away from a stepping target around 100 ms prior to foot contact and the extent of early gaze transfer correlated with stepping errors. The participants returned on a separate day and repeated the experiment; however, the intervention group was instructed to maintain gaze on each target until heel contact. Following intervention, on average participants delayed gaze transfer from the first target until after heel contact and this change in behaviour resulted in a significant reduction in stepping errors. We propose that suboptimal visual sampling strategies contribute to the incidence of falls in the elderly.
Abstract.
Author URL.
Chapters
Young WR, Ellmers TJ (2022). Translating Attentional Control Theory to Applied Psychological Eye Tracking Research. In (Ed) Eye Tracking, Springer Nature, 131-149.
Conferences
Ellmers TJ, Young WR, Paraskevopoulos IT (2017). Integratingfall-risk assessments within a simple balance exergame. 2017 9th International Conference on Virtual Worlds and Games for Serious Applications (VS-Games). 6th - 8th Sep 2017.
Young WR, Rodger MWM, Craig M (2012). Using ecological event-based acoustic guides to cue gait in Parkinson's disease patients.
Author URL.
Publications by year
In Press
Young W (In Press). Exposure Worry: the Psychological Impact of Perceived. Ionizing Radiation Exposure in British Nuclear Test Veterans.
International Journal of Environmental Research and Public HealthAbstract:
Exposure Worry: the Psychological Impact of Perceived. Ionizing Radiation Exposure in British Nuclear Test Veterans
Potential psychological issues faced by British nuclear test veterans have been under-researched. This study assessed the prevalence of clinically relevant anxiety in British nuclear test veterans and aimed to explore experiences of worry and the broader psychological impact of the British nuclear weapons testing programme. The Geriatric Anxiety Inventory (Short-Form) was com-pleted by 89 British nuclear test veterans (33.7% met the criteria for clinically relevant anxiety). Nineteen veterans then participated in semi-structured interviews. Thematic analysis of the data generated three themes. The first theme highlighted how worry was relevant only in a few cases (four) generally regarding their grandchildren’s health, but the guilt in those who perceive re-sponsibility for family health conditions also appeared to be a pertinent issue. The second theme highlighted the anger towards authorities resulting from perceived negligence and deception. The third theme highlighted the relevance of how certain life events across the life course in-fluence the potential psychological impact. This study suggests that guilt must be considered in (potentially) exposed individuals whose family members experience health conditions, which may exacerbate distress. It also suggests the importance that authorities ensure transparency when dealing with any radiological exposure scenario to reduce the potential for anger.
Abstract.
Wang A, Sieber J, Young W, Tsaneva-Atanasova K (In Press). Time series analysis and modelling of the freezing of gait phenomenon.
SIAM Journal on Applied Dynamical SystemsAbstract:
Time series analysis and modelling of the freezing of gait phenomenon
Freezing of Gait (FOG) is one of the most debilitating symptoms of Parkinson's Disease and is associated with falls and loss of independence. The patho-physiological mechanisms underpinning FOG are currently poorly understood. In this paper we combine time series analysis and mathematical modelling to study the FOG phenomenon's dynamics. We focus on the transition from stepping in place into freezing and treat this phenomenon in the context of an escape from an oscillatory attractor into an equilibrium attractor state. We extract a discrete-time discrete-space Markov chain from experimental data and divide its state space into communicating classes to identify the transition into freezing. This allows us to develop a methodology for computationally estimating the time to freezing as well as the phase along the oscillatory (stepping) cycle of a patient experiencing Freezing Episodes (FE). The developed methodology is general and could be applied to any time series featuring transitions between different dynamic regimes including time series data from forward walking in people with FOG.
Abstract.
2024
Lamb SE, Williams G, Young W (2024). The science of falls and how to prevent them.
Nat Med,
30(1), 35-36.
Author URL.
2023
Raffegeau TE, Young WR, Fino PC, Williams AM (2023). A Perspective on Using Virtual Reality to Incorporate the Affective Context of Everyday Falls into Fall Prevention. JMIR Aging, 6
Siragy T, Russo Y, Young W, Lamb SE (2023). Comparison of over-ground and treadmill perturbations for simulation of real-world slips and trips: a systematic review.
Gait Posture,
100, 201-209.
Abstract:
Comparison of over-ground and treadmill perturbations for simulation of real-world slips and trips: a systematic review.
BACKGROUND: Trips and slips increase fall risk for young and older adults. To examine recovery responses, studies utilized treadmill and/or over-ground methods to simulate real-world perturbations. However, differences in the recovery response between treadmill and over-ground perturbations remain unexamined. RESEARCH QUESTION: to assess the current literature on the reactive recovery responses between over-ground- and split-belt treadmill trips and slips as well as the effect of aging on these responses. METHODS: PubMed, Medline, Web of Science, SCOPUS, and Cochrane databases were searched for publications examining trips and slips in healthy young, healthy older adults, and older adults who fall. Included articles were in English, full-text accessible, and biomechanically quantified the reactive recovery responses for slips and trips during either over-ground or split-belt treadmill protocols. The initial database search yielded 1075 articles and 31 articles were included after title, abstract, and full-text screening. RESULTS: for slips, 7 articles utilized lubricated surfaces while 5 articles used treadmills. Further, 3 studies examined differences between older and younger adults. For trips, 9 articles utilized obstacles and 7 used treadmills. Further, 4 articles examined differences between older and young adults and 1 article only examined older adults during over-ground trips. For both perturbations, treadmill and over-ground protocols demonstrated similar anteroposterior destabilization on the center of mass. In the mediolateral direction, over-ground slips consistently found a lateral destabilization while treadmill articles did not examine this direction. Foot placement recovery responses varied less for both perturbation directions on a treadmill compared to over-ground. SIGNIFICANCE: Although treadmill and over-ground perturbations destabilize the center of mass similarly, the recovery response to these perturbations were different on treadmills. Specifically, recovery responses were more consistent for both slips and trips on treadmills. As older adults have difficulty in perturbation recovery scaling, treadmills may be limited in their ability to investigate the variety of aging impairments on perturbation recovery responses.
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Author URL.
Rose DC, Poliakoff E, Young WR, Phillips M (2023). Music Moves Me in More Ways Than One: an Online Survey Investigating the Everyday Use of Music among People with Parkinson's.
Music and Science,
6Abstract:
Music Moves Me in More Ways Than One: an Online Survey Investigating the Everyday Use of Music among People with Parkinson's
Background: Music has been used in interventions designed for people with Parkinson's (PwP) either to engage mechanisms involved in phenomena such as sensorimotor synchronization or as an integral part of the activity (e.g. dance). However, little research has been conducted concerning what music PwP use in everyday life and how and why this might differ based on situation/context. Methods: We used an online survey to investigate what music PwP listen to, for which perceived reasons, and in which situations. In addition to demographic and Parkinson's-specific questions, we included standardized measures of quality of life, music and dance sophistication and bespoke items to explore music use. Results: the sample (N = 217, age range 20–88 years, Mean = 65.2, SD = 8.45) included 109 females (50%); 64% of participants reported a mild impact of Parkinson's on Activities of Daily Living. The top three uses of music were Aesthetic Appreciation (98%), Relaxation (92%), and Motivation (90%). The least popular category was using music for walking (36%). The duration of attentive listening was significantly higher for those who reported using music for managing their feelings than those who did not (p
Abstract.
Raffegeau TE, Clark M, Fawver B, Engel BT, Young WR, Williams AM, Lohse KR, Fino PC (2023). The effect of mobility-related anxiety on walking across the lifespan: a virtual reality simulation study.
Exp Brain Res,
241(7), 1757-1768.
Abstract:
The effect of mobility-related anxiety on walking across the lifespan: a virtual reality simulation study.
Older adults who report a fear of falling are more likely to subsequently fall, yet, some gait anxiety-related alterations may protect balance. We examined the effect of age on walking in anxiety-inducing virtual reality (VR) settings. We predicted a high elevation-related postural threat would impair gait in older age, and differences in cognitive and physical function would relate to the observed effects. Altogether, 24 adults (age (y) = 49.2 (18.7), 13 women) walked on a 2.2-m walkway at self-selected and fast speeds at low (ground) and high (15 m) VR elevation. Self-reported cognitive and somatic anxiety and mental effort were greater at high elevations (all p
Abstract.
Author URL.
Ellmers TJ, Wilson MR, Kal EC, Young WR (2023). The perceived control model of falling: developing a unified framework to understand and assess maladaptive fear of falling.
Age Ageing,
52(7).
Abstract:
The perceived control model of falling: developing a unified framework to understand and assess maladaptive fear of falling.
BACKGROUND: fear of falling is common in older adults and can have a profound influence on a variety of behaviours that increase fall risk. However, fear of falling can also have potentially positive outcomes for certain individuals. Without progressing our understanding of mechanisms underlying these contrasting outcomes, it is difficult to clinically manage fear of falling. METHODS: this paper first summarises recent findings on the topic of fear of falling, balance and fall risk-including work highlighting the protective effects of fear. Specific focus is placed on describing how fear of falling influences perceptual, cognitive and motor process in ways that might either increase or reduce fall risk. Finally, it reports the development and validation of a new clinical tool that can be used to assess the maladaptive components of fear of falling. RESULTS: we present a new conceptual framework-the Perceived Control Model of Falling-that describes specific mechanisms through which fear of falling can influence fall risk. The key conceptual advance is the identification of perceived control over situations that threaten one's balance as the crucial factor mediating the relationship between fear and increased fall risk. The new 4-item scale that we develop-the Updated Perceived Control over Falling Scale (UP-COF)-is a valid and reliable tool to clinically assess perceived control. CONCLUSION: this new conceptualisation and tool (UP-COF) allows clinicians to identify individuals for whom fear of falling is likely to increase fall risk, and target specific underlying maladaptive processes such as low perceived control.
Abstract.
Author URL.
Poliakoff E, Bek J, Phillips M, Young WR, Rose DC (2023). Vividness and Use of Imagery Related to Music and Movement in People with Parkinson's: a Mixed-methods Survey Study.
Music and Science,
6Abstract:
Vividness and Use of Imagery Related to Music and Movement in People with Parkinson's: a Mixed-methods Survey Study
Parkinson's disease affects multiple aspects of movement, impacting significantly on everyday tasks. Music is used in interventions for people with Parkinson's, either to pace movements, or as an integral element of activities such as dance. This study explored self-reported vividness of two forms of imagery – motor imagery evoked by music and auditory (including musical) imagery – in people with Parkinson's, and whether and how they use these types of imagery in everyday life. Participants (N = 199) completed: (i) vividness ratings of visual and kinesthetic music-evoked motor imagery, (ii) vividness ratings of auditory imagery, and (iii) ratings and open questions about their everyday use of these types of imagery. While most participants reported experiencing music-evoked motor imagery (with more vivid visual than kinesthetic motor imagery),
Abstract.
Alenezi S, Morgan-Trimmer S, Hulbert S, Young W, Goodwin VA (2023). “It's a lot more complicated than it seems”: physiotherapists' experiences of using compensation strategies in people with Parkinson's.
Frontiers in Rehabilitation Sciences,
4Abstract:
“It's a lot more complicated than it seems”: physiotherapists' experiences of using compensation strategies in people with Parkinson's
BackgroundGait disturbances often result in functional limitations in daily activities and negatively impact the quality of life in people with Parkinson's disease. Physiotherapists often employ compensation strategies in an attempt to improve patients' walking. However, little is known about physiotherapists' experiences in this regard. We evaluated how physiotherapists adopt compensation strategies and what they draw on to inform their clinical decision-making.MethodsWe carried out semi-structured online interviews with 13 physiotherapists with current or recent experience working with people with Parkinson's disease in the United Kingdom. Interviews were digitally recorded and transcribed verbatim. Thematic analysis was utilized.ResultsTwo main themes were developed from the data. The first theme, optimizing compensation strategies through personalized care, shows how physiotherapists accounted for the individual needs and characteristics of people with Parkinson's, which resulted in them individually tailoring compensation strategies. The second theme, delivering compensation strategies effectively, considers the available support and perceived challenges with work settings and experience that impact physiotherapists' ability to deliver compensation strategies.DiscussionAlthough physiotherapists strived to optimize compensation strategies, there was a lack of formal training in this area, and their knowledge was primarily acquired from peers. Furthermore, a lack of specific knowledge on Parkinson's can impact physiotherapists’ confidence in maintaining person-centered rehabilitation. However, the question that remains to be answered is what accessible training could address the knowledge–practice gap to contribute to the delivery of better-personalized care for people with Parkinson's.
Abstract.
2022
Kal EC, Young WR, Ellmers TJ (2022). Balance capacity influences the effects of conscious movement processing on postural control in older adults.
Human Movement Science,
82Abstract:
Balance capacity influences the effects of conscious movement processing on postural control in older adults
Older adults rely increasingly on conscious processes to control balance. While this could be in response to age-related declines in balance capacity, it is unclear whether such strategy is adaptive or not. We investigated whether balance capacity modified the effects of conscious movement processing (CMP) on postural control in older adults. Forty-seven older adults (Mage = 74.8, range = 61–88) completed 60-s, narrow-stance balance trials on a force platform, under conditions designed to increase (high-CMP; through movement-monitoring instructions) or reduce conscious processing (low-CMP; distraction task). Balance capacity was operationalised as a composite score of Berg Balance Scale and Timed-up-and-Go. Balance capacity influenced the effects of the CMP manipulation on mediolateral sway amplitude (p =. 023). Specifically, it positively associated with sway amplitude during the high-CMP condition (β = 0.273), but not low-CMP condition (β = −0.060). In other words, higher balance capacity was associated with increased sway during high-CMP, confirming our hypothesis that CMP does not uniformly negatively impact balance performance. Rather, CMP was maladaptive for those with better balance. Results also indicated that older adults' balance capacity influenced the degree to which they could engage conscious or automatic postural control processes. Specifically, we found that, overall, participants showed reduced mediolateral sway frequency and complexity for the high-CMP vs. low-CMP condition (p's ≤ 0.018), indicating reduced automaticity of balance (as expected). However, these effects were significantly attenuated as balance capacity reduced (i.e. smaller changes in those with lower balance capacity, p's < 0.010). Hence, the ability to readily shift between conscious and automatic modes of postural control seems more constrained as balance becomes worse. Overall, these findings suggest clinicians need to consider older adults' balance capacity when using providing instructions or feedback likely to influence CMP within rehabilitation settings.
Abstract.
Raffegeau TE, Fawver B, Clark M, Engel BT, Young WR, Williams AM, Lohse KR, Fino PC (2022). Corrigendum to “The feasibility of using virtual reality to induce mobility-related anxiety during turning” [Gait & Posture 77 (2020) 6–13, (Gait & Posture (2020) 77(6–13) (S0966636220300072), (10.1016/j.gaitpost.2020.01.006)).
Gait and Posture,
95Abstract:
Corrigendum to “The feasibility of using virtual reality to induce mobility-related anxiety during turning” [Gait & Posture 77 (2020) 6–13, (Gait & Posture (2020) 77(6–13) (S0966636220300072), (10.1016/j.gaitpost.2020.01.006))
The authors regret that editors were incorrectly listed as authors in a citation in our original publication. Instead, citation number 1 should read: [1] Adkin, A.L. Carpenter, M.G. 2018. New insights on emotional contributions to human postural control. Front. Neurol. 9, 789. https://doi.org/10.3389/fneur.2018.00789 the authors sincerely apologise for any inconvenience caused.
Abstract.
Rose DC, Poliakoff E, Hadley R, Guérin SMR, Phillips M, Young WR (2022). Levelling the Playing Field: the Role of Workshops to Explore How People with Parkinson's Use Music for Mood and Movement Management as Part of a Patient and Public Involvement Strategy.
Front Rehabil Sci,
3Abstract:
Levelling the Playing Field: the Role of Workshops to Explore How People with Parkinson's Use Music for Mood and Movement Management as Part of a Patient and Public Involvement Strategy.
From a humanistic perspective, participatory processes in research find support on both ethical and moral grounds. In practical terms however, it is often difficult to establish protocols that best honour (i.e. elicit, capture, and integrate) the opinions of individuals and groups that represent the various specific stakeholders (e.g. from allied health, scientific, and academic disciplines) needed to investigate complex phenomena. Here, we describe a consultation process (funded by Parkinson's UK) devised to explore use of music among people with Parkinson's in relation to potential applications to enhance quality of life. People with Parkinson's were paired with researchers in order to discuss music on an equal footing so as to enable participant empowerment. We describe outcomes that demonstrate avenues of success as a result of this approach and additional insights gained through these processes in the hope of informing future practise. It has been our experience that researchers must establish a balance between (a) ensuring methodological rigour within an appropriate framework, and (b) facilitating informal "playtime" that develops connectivity between participants and enables both creative thinking and reflexive practise amongst stakeholders. We encourage researchers not to underestimate "playtime" as an important vehicle to foster this social interactivity and fuel the good will required to conduct inclusive and relevant research.
Abstract.
Author URL.
Ellmers T, Wilson M, Norris M, Young W (2022). Protective or harmful? a qualitative exploration of older people’s perceptions of worries about falling. Age and Ageing
Ellmers TJ, Wilson MR, Kal EC, Young WR (2022). Standing up to threats: Translating the two-system model of fear to balance control in older adults. Experimental Gerontology, 158, 111647-111647.
Wang A, Sieber J, Young WR, Tsaneva-Atanasova K (2022). Time series analysis and modelling of the freezing of gait phenomenon.
Abstract:
Time series analysis and modelling of the freezing of gait phenomenon
Freezing of Gait (FOG) is one of the most debilitating symptoms of
Parkinson's Disease and is associated with falls and loss of independence. The
patho-physiological mechanisms underpinning FOG are currently poorly
understood. In this paper we combine time series analysis and mathematical
modelling to study the FOG phenomenon's dynamics. We focus on the transition
from stepping in place into freezing and treat this phenomenon in the context
of an escape from an oscillatory attractor into an equilibrium attractor state.
We extract a discrete-time discrete-space Markov chain from experimental data
and divide its state space into communicating classes to identify the
transition into freezing. This allows us to develop a methodology for
computationally estimating the time to freezing as well as the phase along the
oscillatory (stepping) cycle of a patient experiencing Freezing Episodes (FE).
The developed methodology is general and could be applied to any time series
featuring transitions between different dynamic regimes including time series
data from forward walking in people with FOG.
Abstract.
Author URL.
Young WR, Ellmers TJ (2022). Translating Attentional Control Theory to Applied Psychological Eye Tracking Research. In (Ed) Eye Tracking, Springer Nature, 131-149.
Kal EC, Ellmers TJ, Fielding AE, Hardeman L, Coito J, Joyce L, Young WR (2022). Weighting for the Beat: Using a Dance Cue to Facilitate Turning in People with Parkinson's Disease and Freezing of Gait.
J Parkinsons Dis,
12(4), 1353-1358.
Abstract:
Weighting for the Beat: Using a Dance Cue to Facilitate Turning in People with Parkinson's Disease and Freezing of Gait.
Freezing of gait (FOG) can severely compromise daily functioning in people with Parkinson's disease. Inability to initiate a step from FOG is likely underpinned, at least in part, by a deficient preparatory weight-shift. Conscious attempts to weight-shift in preparation to step can improve success of initiating forward steps following FOG. However, FOG often occurs during turning, where weight-shifting is more complex and risk of falling is higher. We explored the effectiveness of a dance-based ('cha-cha') weight-shifting strategy to re-initiate stepping following FOG during turning. Results suggest that this simple movement strategy can enhance turning steps following FOG, without compromising safety.
Abstract.
Author URL.
Collett G, Martin W, Young WR, Anderson RM (2022). “Is that a coincidence?”: Exploring health perceptions and the causal attributions of physical health conditions in British nuclear test veterans. SSM - Qualitative Research in Health, 2, 100127-100127.
2021
Cocks AJ, Young WR, Ellmers TJ, Jackson RC, Williams AM (2021). Concern about falling is associated with segmental control when turning in older adults.
Gait Posture,
88, 105-108.
Abstract:
Concern about falling is associated with segmental control when turning in older adults.
BACKGROUND: Healthy young adults typically exhibit a progressive 'top-down' reorientation of body segments (i.e. head, trunk, then pelvis) during turning. This behaviour is less evident in older adults at risk of falling, who often reduce angular displacement between body segments during turns. The potential functional and psychological contributors to this so-called 'en-bloc' turning strategy are not yet understood. RESEARCH QUESTION: Are there associations between concern about falling and variables representing en-bloc turning (i.e. increased coupling between body segments)? METHODS: Twenty-one older adults were assessed while turning during an adaptive walking task. We collected data from markers forming the head, trunk, and pelvis segments, while gait velocity throughout the turn was calculated from a sternum marker. We correlated several variables with concern about falling alone, as well as while controlling for functional balance ability. RESULTS: Correlation analyses revealed that concern about falling was related to en-bloc turning strategies and slower gait velocity throughout the turn, when analysed independently of functional balance. When controlling for balance ability, en-bloc turning strategies between the head and trunk, as well as the head and pelvis, remained significantly associated with concern about falling. SIGNIFICANCE: Findings offer an insight into the potential role that psychological characteristics may have in determining older adults' turning behaviour and associated risk of falling.
Abstract.
Author URL.
Mak TCT, Young WR, Wong TWL (2021). Conscious Control of Gait Increases with Task Difficulty and can be Mitigated by External Focus Instruction. Experimental Aging Research, 47(3), 288-301.
Young W, Ellmers TJ (2021). Translating Attentional Control Theory to Applied Psychological Eye Tracking Research.
Abstract:
Translating Attentional Control Theory to Applied Psychological Eye Tracking Research
This chapter will describe how eye tracking outcomes can be used to evaluate psychological processes, particularly in applied contexts (e.g. clinical anxiety disorders, elite motor performance and rehabilitation settings). Our discussion will focus primarily on the influence of emotion on two key aspects of attentional processing related to Attentional Control Theory: i) attentional bias for threatening stimuli, and ii) processing (in)efficiency. We present key metrics than can be used to infer these processes and describe that previous management of outcome measures can be allocated into two categories: transferred and retrofitted. This content is primarily aimed at readers thinking about using eye-tracking in the context of psychological research and practice; to help them design their task(s) and select appropriate outcome measures in order to avoid potential confounds.
Abstract.
2020
Ellmers T, Cocks A, Kal E, Young W (2020). Conscious movement processing, fall-related anxiety, and the visuomotor control of locomotion in older adults. Journal of Gerontology Series B: Psychological Sciences and Social Sciences
Ellmers T, Kal E, Young W (2020). Consciously processing balance leads to distorted perceptions of instability in older adults. Journal of Neurology
Parakkal Unni M, Menon PP, Livi L, Wilson MR, Young WR, Bronte-Stewart HM, Tsaneva-Atanasova K (2020). Data-Driven Prediction of Freezing of Gait Events from Stepping Data.
Frontiers in Medical Technology,
2, 581264-581264.
Abstract:
Data-Driven Prediction of Freezing of Gait Events from Stepping Data
Freezing of gait (FoG) is typically a symptom of advanced Parkinson’s disease (PD) that negatively influences the quality of life and is often resistant to pharmacological interventions. Novel treatment options that make use of auditory or sensory cues might be optimized by prediction of freezing events. These predictions might help to trigger external sensory cues—shown to improve walking performance—when behavior is changed in a manner indicative of an impending freeze (i.e. when the user needs it the most), rather than delivering cue information continuously. A data-driven approach is proposed for predicting freezing events using Random Forrest (RF), Neural Network (NN), and Naive Bayes (NB) classifiers. Vertical forces, sampled at 100 Hz from a force platform were collected from 9 PD subjects as they stepped in place until they at least had one freezing episode or for 90 s. The F1 scores of RF/NN/NB algorithms were computed for different IL (input to the machine learning algorithm), and GL (how early the freezing event is predicted). A significant negative correlation between the F1 scores and GL, highlighting the difficulty of early detection is found. The IL that maximized the F1 score is approximately equal to 1.13 s. This indicates that the physiological (and therefore neurological) changes leading to freezing take effect at-least one step before the freezing incident. Our algorithm has the potential to support the development of devices to detect and then potentially prevent freezing events in people with Parkinson’s which might occur if left uncorrected.
Abstract.
Ellmers TJ, Cocks AJ, Young WR (2020). Evidence of a Link Between Fall-Related Anxiety and High-Risk Patterns of Visual Search in Older Adults During Adaptive Locomotion.
J Gerontol a Biol Sci Med Sci,
75(5), 961-967.
Abstract:
Evidence of a Link Between Fall-Related Anxiety and High-Risk Patterns of Visual Search in Older Adults During Adaptive Locomotion.
BACKGROUND: Older adults deemed to be at a high risk of falling will often display visual search behaviors likely to impair movement planning when negotiating environmental hazards. It has been proposed that these behaviors may be underpinned by fall-related anxiety. Thus, the aim of this study was to explore the effects of fall-related anxiety on visual search and stepping behaviors during adaptive gait. METHODS: Forty-four community-dwelling older adults (mean age = 74.61; standard deviation = 6.83) walked along a path and stepped into two raised targets. All participants completed walks at ground level, whereas participants deemed to be at a low risk of falling (n = 24) also completed walks under conditions designed to induce fall-related anxiety (walkway elevated 0.6 m). Participants' movement kinematics and gaze behavior were measured. RESULTS: During ground trials, "high-risk" participants visually prioritized the immediate walkway areas 1-2 steps ahead, at the expense of previewing future stepping constraints. This reduced planning appeared to negatively affect safety, with greater stepping errors observed for future constraints. When completing walks on the elevated walkway, "low-risk" participants similarly prioritized immediate walkway areas, at the expense of planning future stepping actions. These behaviors were associated with greater attention directed toward consciously processing walking movements. CONCLUSIONS: These findings provide evidence of a link between heightened fall-related anxiety and "high-risk" visual search behaviors associated with greater stepping errors. This information enhances our understanding of why high-risk older adults are less able to safely navigate environmental constraints.
Abstract.
Author URL.
Kal EC, Young WR, Ellmers TJ (2020). Face masks, vision, and risk of falls.
BMJ,
371 Author URL.
Ellmers T, Maslivec A, Young W (2020). Fear of falling alters anticipatory postural control during cued gait initiation. Neuroscience
Young W, Ellmers T, Kinrade N, Cossar J, Cocks A (2020). Re-evaluating the measurement and influence of conscious movement processing on gait performance in older adults: development of the Gait-Specific Attentional Profile. Gait and Posture
Ellmers T, Kal E, Richardson J, Young W (2020). Short-latency inhibition mitigates the relationship between conscious movement processing and overly cautious gait. Age and Ageing
Raffegeau T, Fawver B, Young W, Williams AM, Lohse K, Fino P (2020). The direction of postural threat alters balance control when standing at virtual elevation. Experimental Brain Research
Raffegeau TE, Fawver B, Clark M, Engel BT, Young WR, Williams AM, Lohse KR, Fino PC (2020). The feasibility of using virtual reality to induce mobility-related anxiety during turning. Gait & Posture, 77, 6-13.
Collett G, Craenen K, Young W, Gilhooly M, Anderson R (2020). The psychological consequences of (perceived) ionizing radiation exposure: a review on its role in radiation-induced cognitive dysfunction. International Journal of Radiation Biology
Mak TCT, Young WR, Wong TWL (2020). The role of reinvestment in conservative gait in older adults. Experimental Gerontology, 133, 110855-110855.
Hardeman LES, Kal EC, Young WR, van der Kamp J, Ellmers TJ (2020). Visuomotor control of walking in Parkinson’s disease: Exploring possible links between conscious movement processing and freezing of gait. Behavioural Brain Research, 395, 112837-112837.
Maslivec A, Fielding A, Wilson M, Norris M, Young W (2020). ‘Recoupling’ the attentional and motor control of preparatory postural adjustments to overcome Freezing of Gait in Parkinson’s. Journal of NeuroEngineering and Rehabilitation, 17
2019
Ellmers TJ, Cocks AJ, Young WR (2019). Exploring attentional focus of older adult fallers during heightened postural threat.
Psychological ResearchAbstract:
Exploring attentional focus of older adult fallers during heightened postural threat
© 2019, the Author(s). Objectives: Threats to balance, and subsequent increases in fall-related anxiety, can disrupt attentional processing during gait in older adults, leading to behavioral adaptations which may increase fall risk. However, limited research has investigated what changes in attention occur to contribute to these disruptions. The aim of this research was to describe changes in attention that occur during gait when older adults’ balance is threatened, while exploring how previous fall history and trait movement reinvestment (conscious monitoring and control of movement) also influence attention. Methods: Forty older adults reported where they focus their attention when walking during two scenarios: (1) when they are relaxed and there is little risk of falling, and; (2) when their balance is threatened and they are anxious of falling. Results: During the high-threat condition, participants reported greater attention towards movement processes, threats to balance, worries/disturbing thoughts and self-regulatory strategies, with less attention directed towards task-irrelevant thoughts. However, fall history influenced attentional focus, with fallers directing greater attention towards worries/disturbing thoughts. Contrary to predictions, trait movement reinvestment was not associated with attention directed towards movement processes. Discussion: As processing worries/disturbing thoughts will likely reduce attentional resources available for effective postural control, we highlight this as one potential area to target interventions aimed at reducing the likelihood of repeated falling.
Abstract.
Chan DCL, Wong TWL, Zhu FF, Lam CC, Young W, Capio CM, Masters RSW (2019). Investigating changes in real-time conscious postural processing by older adults during different stance positions using electroencephalography coherence. Experimental Aging Research
Amini A, Banitsas K, Young WR (2019). Kinect4FOG: monitoring and improving mobility in people with Parkinson's using a novel system incorporating the Microsoft Kinect v2.
Disabil Rehabil Assist Technol,
14(6), 566-573.
Abstract:
Kinect4FOG: monitoring and improving mobility in people with Parkinson's using a novel system incorporating the Microsoft Kinect v2.
Parkinson's is a neurodegenerative condition associated with several motor symptoms including tremors and slowness of movement. Freezing of gait (FOG); the sensation of one's feet being "glued" to the floor, is one of the most debilitating symptoms associated with advanced Parkinson's. FOG not only contributes to falls and related injuries, but also compromises quality of life as people often avoid engaging in functional daily activities both inside and outside the home. In the current study, we describe a novel system designed to detect FOG and falling in people with Parkinson's (PwP) as well as monitoring and improving their mobility using laser-based visual cues cast by an automated laser system. The system utilizes a RGB-D sensor based on Microsoft Kinect v2 and a laser casting system consisting of two servo motors and an Arduino microcontroller. This system was evaluated by 15 PwP with FOG. Here, we present details of the system along with a summary of feedback provided by PwP. Despite limitations regarding its outdoor use, feedback was very positive in terms of domestic usability and convenience, where 12/15 PwP showed interest in installing and using the system at their homes. Implications for Rehabilitation Providing an automatic and remotely manageable monitoring system for PwP gait analysis and fall detection. Providing an automatic, unobtrusive and dynamic visual cue system for PwP based on laser line projection. Gathering feedback from PwP about the practical usage of the implemented system through focus group events.
Abstract.
Author URL.
Chow VWK, Ellmers TJ, Young WR, Mak TCT, Wong TWL (2019). Revisiting the relationship between internal focus and balance control in young and older adults.
Frontiers in Neurology,
10(JAN).
Abstract:
Revisiting the relationship between internal focus and balance control in young and older adults
© 2019 Chow, Ellmers, Young, Mak and Wong. Research highlights the detrimental effect that directing too much conscious attention toward movement can have on postural control. While this concept has received support from many studies, recent evidence demonstrates that this principle does not always translate to aging clinical populations. Given the increasing clinical interest in this topic, the current study evaluated if the original notion (that an internal focus results in compromised balance performance) is upheld in young and older adults during a challenging balance task where we are able to objectively corroborate changes in attentional focus; using an electroencephalography (EEG) method previously identified as an objective indicator of conscious movement control. This method assesses the neural coherence, or “communication,” between T3 (verbal-analytical) and Fz (motor-planning) regions of the brain. Thirty-nine young and 40 older adults performed a challenging balance task while holding a 2-meter pole under two randomized conditions: Baseline and Internal focus of attention (directing attention internally toward movement production). Results showed that young adults demonstrated increased EEG T3-Fz coherence in conjunction with increased sway path during the Internal focus condition. However, no significant differences were observed in older adults between conditions for any measure. The current study provides supporting evidence for the detrimental effect that adopting an Internal focus can have on postural control-especially in populations able to govern these processes in a relatively “automatic” manner (e.g. young adults). However, this work illustrates that such observations may not readily translate between populations and are not robust to age-related changes. Further work is necessary to examine mechanisms underlying this clear translational issue.
Abstract.
Mak TCT, Young W, Lam WK, Tse ACY, Wong TWL (2019). The Role of Attentional Focus on Walking Efficiency among Older Fallers and Non-fallers. Age and Ageing
Ellmers TJ, Young WR (2019). The influence of anxiety and attentional focus on visual search during adaptive gait. Journal of Experimental Psychology: Human Perception and Performance, 45(6), 697-714.
2018
Doumas M, Morsanyi K, Young WR (2018). Cognitively and socially induced stress affects postural control.
Exp Brain Res,
236(1), 305-314.
Abstract:
Cognitively and socially induced stress affects postural control.
Postural control is an adaptive process that can be affected by many aspects of human behavior, including emotional contexts. The main emotional contexts that affect postural control are postural threat and passive viewing of aversive or threatening images, both of which produce a reduction in postural sway. The aim of the present study was to assess whether similar stress-related changes in postural sway can be observed using stress induced by social evaluative threat (SET) while performing arithmetic tasks. Twelve young adults performed an arithmetic and a postural control task separately, concurrently, and concurrently with added time pressure in the arithmetic task. In the final condition, participants were given negative feedback about their performance in the arithmetic task and performed it again while being observed (SET condition). Results showed that stress increased linearly with task demand. Postural sway and reaction times were not affected by the first two conditions; however, when time pressure was introduced, reaction times became faster and sway amplitude increased. Finally, introduction of SET caused the predicted reduction in postural sway and an increase in reaction times relative to the time pressure condition. Our results suggest that stress induced using a combination of arithmetic tasks and social evaluative threat leads to systematic changes in postural control. The paradigm developed in the present study would be very useful in assessing interactions between cognition, stress, and postural control in the context of postural instability and falls in older adults.
Abstract.
Author URL.
Ellmers TJ, Young WR (2018). Conscious motor control impairs attentional processing efficiency during precision stepping. Gait & Posture, 63, 58-62.
Mak TCT, Young WR, Chan DCL, Wong TWL (2018). Gait Stability in Older Adults During Level-Ground Walking: the Attentional Focus Approach. The Journals of Gerontology: Series B
Ellmers TJ, Paraskevopoulos IT, Williams AM, Young WR (2018). Recalibrating disparities in perceived and actual balance abilities in older adults: a mixed-methods evaluation of a novel exergaming intervention.
J Neuroeng Rehabil,
15(1).
Abstract:
Recalibrating disparities in perceived and actual balance abilities in older adults: a mixed-methods evaluation of a novel exergaming intervention.
BACKGROUND: Published reports suggest a disparity between perceived and actual balance abilities, a trait associated with increased fall-risk in older adults. We investigate whether it is possible to 'recalibrate' these disparities using a novel gaming intervention. METHODS: We recruited 26 older adults for a 4-week intervention in which they participated in 8-sessions using a novel gaming intervention designed to provide explicit, augmented feedback related to postural control. Measures of perceived balance abilities (Falls Efficacy Scale-International) and actual postural control (limits of stability) were assessed pre- and post-intervention. We used focus groups to elicit the opinions of participants about how the game may have influenced balance abilities and confidence. RESULTS: a stronger alignment was observed between postural control and perceived balance capabilities post-intervention (i.e. significant correlations between Falls Efficacy Scale-International scores and limits of stability which were not present pre-intervention). Also, significant improvements in measures of postural control were observed, with these improvements confined to the aspects of postural control for which the exergame provided explicit, augmented feedback. Qualitative data revealed that the intervention made participants more "aware" of their balance abilities. CONCLUSIONS: Our results demonstrate that it is possible to recalibrate the perceptions of older adults relating to their balance abilities through a targeted, short-term intervention. We propose that the post-intervention improvements in postural control may have been, in part, the result of this recalibration; with altered perceptions leading to changes in balance performance. Findings support the application of novel interventions aimed at addressing the psychological factors associated with elderly falls.
Abstract.
Author URL.
Uiga L, Capio CM, Ryu D, Young WR, Wilson MR, Wong TWL, Tse ACY, Masters RSW (2018). The Role of Movement-Specific Reinvestment in Visuomotor Control of Walking by Older Adults.
Journals of Gerontology, Series B,
75(2), 282-292.
Abstract:
The Role of Movement-Specific Reinvestment in Visuomotor Control of Walking by Older Adults
Objectives: the aim of this study was to examine the association between conscious monitoring and control of movements (i.e. movement specific reinvestment) and visuo-motor control during walking by older adults. Method: the Movement Specific Reinvestment Scale (MSRS; Masters, Eves, & Maxwell, 2005) was administered to ninety-two community-dwelling older adults, aged 65-81 years, who were required to walk along a 4.8-meter walkway and step on the middle of a target as accurately as possible. Participants' movement kinematics and gaze behavior were measured during approach to the target and when stepping on it. Results: High scores on the MSRS were associated with prolonged stance and double support times during approach to the stepping target, and less accurate foot placement when stepping on the target. No associations between MSRS and gaze behavior were observed. Discussion: Older adults with a high propensity for movement specific reinvestment seem to need more time to "plan" future stepping movements, yet show worse stepping accuracy than older adults with a low propensity for movement specific reinvestment. Future research should examine whether older adults with a higher propensity for reinvestment are more likely to display movement errors that lead to falling.
Abstract.
2017
Ellmers TJ, Young WR, Paraskevopoulos IT (2017). Integratingfall-risk assessments within a simple balance exergame. 2017 9th International Conference on Virtual Worlds and Games for Serious Applications (VS-Games). 6th - 8th Sep 2017.
Keune PM, Young WR, Paraskevopoulos IT, Hansen S, Muenssinger J, Oschmann P, Müller R (2017). Measuring standing balance in multiple sclerosis: Further progress towards an automatic and reliable method in clinical practice. Journal of the Neurological Sciences, 379, 157-162.
2016
Ellmers TJ, Machado G, Wong TW-L, Zhu F, Williams AM, Young WR (2016). A validation of neural co-activation as a measure of attentional focus in a postural task.
Gait Posture,
50, 229-231.
Abstract:
A validation of neural co-activation as a measure of attentional focus in a postural task.
Postural threat can induce conscious involvement in movement control. This internal focus has been implicated in compromising attentional processing efficiency during postural control, leading to behavioral adaptations that might increase the risk of falling in the elderly. It is suggested that electroencephalography (EEG) coherence, or 'communication', between T3 (verbal-analytical) and Fz (motor-planning) regions may provide an objective measure of internal focus in learned movement skills. However, it is currently unknown whether this experimental technique can be applied to the control of gait and posture; skills which develop early in life, without the use of declarative knowledge/explicit verbal cues to guide performance. We validate the utility of the EEG T3-Fz coherence analysis in a postural task. A total of 24 young adults produced small voluntary swaying movements in medial-lateral or anterior-posterior direction under conditions that directed their attentional focus either internally or externally. Although EEG coherence was sensitive to voluntary changes in attentional focus, the lack of observed between-group (High/Low-trait-reinvestment) difference in coherence may suggest that younger adults cannot be assumed to utilize explicit verbal cues to control voluntary postural sway unless explicitly instructed to do so. As a result, while these results indicate that EEG T3-Fz is a valid technique for assessing attentional focus in postural tasks, our data do not support the clinical application of this method of analysis in providing an objective indication of trait-reinvestment in tasks involving voluntary postural sway.
Abstract.
Author URL.
Young WR, Shreve L, Quinn EJ, Craig C, Bronte-Stewart H (2016). Auditory cueing in Parkinson's patients with freezing of gait. What matters most: Action-relevance or cue-continuity?.
Neuropsychologia,
87, 54-62.
Abstract:
Auditory cueing in Parkinson's patients with freezing of gait. What matters most: Action-relevance or cue-continuity?
Gait disturbances are a common feature of Parkinson's disease, one of the most severe being freezing of gait. Sensory cueing is a common method used to facilitate stepping in people with Parkinson's. Recent work has shown that, compared to walking to a metronome, Parkinson's patients without freezing of gait (nFOG) showed reduced gait variability when imitating recorded sounds of footsteps made on gravel. However, it is not known if these benefits are realised through the continuity of the acoustic information or the action-relevance. Furthermore, no study has examined if these benefits extend to PD with freezing of gait. We prepared four different auditory cues (varying in action-relevance and acoustic continuity) and asked 19 Parkinson's patients (10 nFOG, 9 with freezing of gait (FOG)) to step in place to each cue. Results showed a superiority of action-relevant cues (regardless of cue-continuity) for inducing reductions in Step coefficient of variation (CV). Acoustic continuity was associated with a significant reduction in Swing CV. Neither cue-continuity nor action-relevance was independently sufficient to increase the time spent stepping before freezing. However, combining both attributes in the same cue did yield significant improvements. This study demonstrates the potential of using action-sounds as sensory cues for Parkinson's patients with freezing of gait. We suggest that the improvements shown might be considered audio-motor 'priming' (i.e. listening to the sounds of footsteps will engage sensorimotor circuitry relevant to the production of that same action, thus effectively bypassing the defective basal ganglia).
Abstract.
Author URL.
Young WR, Olonilua M, Masters RSW, Dimitriadis S, Mark Williams A (2016). Examining links between anxiety, reinvestment and walking when talking by older adults during adaptive gait.
Exp Brain Res,
234(1), 161-172.
Abstract:
Examining links between anxiety, reinvestment and walking when talking by older adults during adaptive gait.
Falls by older adults often result in reduced quality of life and debilitating fear of further falls. Stopping walking when talking (SWWT) is a significant predictor of future falls by older adults and is thought to reflect age-related increases in attentional demands of walking. We examine whether SWWT is associated with use of explicit movement cues during locomotion, and evaluate if conscious control (i.e. movement specific reinvestment) is causally linked to fall-related anxiety during a complex walking task. We observed whether twenty-four older adults stopped walking when talking when asked a question during an adaptive gait task. After certain trials, participants completed a visuospatial recall task regarding walkway features, or answered questions about their movements during the walk. In a subsequent experimental condition, participants completed the walking task under conditions of raised postural threat. Compared to a control group, participants who SWWT reported higher scores for aspects of reinvestment relating to conscious motor processing but not movement self-consciousness. The higher scores for conscious motor processing were preserved when scores representing cognitive function were included as a covariate. There were no group differences in measures of general cognitive function, visuospatial working memory or balance confidence. However, the SWWT group reported higher scores on a test of external awareness when walking, indicating allocation of attention away from task-relevant environmental features. Under conditions of increased threat, participants self-reported significantly greater state anxiety and reinvestment and displayed more accurate responses about their movements during the task. SWWT is not associated solely with age-related cognitive decline or generic increases in age-related attentional demands of walking. SWWT may be caused by competition for phonological resources of working memory associated with consciously processing motor actions and appears to be causally linked with fall-related anxiety and increased vigilance.
Abstract.
Author URL.
Ellmers TJ, Cocks AJ, Doumas M, Williams AM, Young WR (2016). Gazing into thin air: the dual-task costs of movement planning and execution during adaptive gait.
PLoS ONE,
11(11).
Abstract:
Gazing into thin air: the dual-task costs of movement planning and execution during adaptive gait
© 2016 Ellmers et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. We examined the effect of increased cognitive load on visual search behavior and measures of gait performance during locomotion. Also, we investigated how personality traits, specifically the propensity to consciously control or monitor movements (trait movement 'reinvestment'), impacted the ability to maintain effective gaze under conditions of cognitive load. Healthy young adults traversed a novel adaptive walking path while performing a secondary serial subtraction task. Performance was assessed using correct responses to the cognitive task, gaze behavior, stepping accuracy, and time to complete the walking task. When walking while simultaneously carrying out the secondary serial subtraction task, participants visually fixated on task-irrelevant areas 'outside' the walking path more often and for longer durations of time, and fixated on task-relevant areas 'inside' the walkway for shorter durations. These changes were most pronounced in high-trait-reinvesters. We speculate that reinvestment-related processes placed an additional cognitive demand upon working memory. These increased task-irrelevant 'outside' fixations were accompanied by slower completion rates on the walking task and greater gross stepping errors. Findings suggest that attention is important for the maintenance of effective gaze behaviors, supporting previous claims that the maladaptive changes in visual search observed in high-risk older adults may be a consequence of inefficiencies in attentional processing. Identifying the underlying attentional processes that disrupt effective gaze behaviour during locomotion is an essential step in the development of rehabilitation, with this information allowing for the emergence of interventions that reduce the risk of falling.
Abstract.
2015
Whyatt C, Merriman NA, Young WR, Newell FN, Craig C (2015). A Wii Bit of Fun: a Novel Platform to Deliver Effective Balance Training to Older Adults.
Games Health J,
4(6), 423-433.
Abstract:
A Wii Bit of Fun: a Novel Platform to Deliver Effective Balance Training to Older Adults.
BACKGROUND: Falls and fall-related injuries are symptomatic of an aging population. This study aimed to design, develop, and deliver a novel method of balance training, using an interactive game-based system to promote engagement, with the inclusion of older adults at both high and low risk of experiencing a fall. STUDY DESIGN: Eighty-two older adults (65 years of age and older) were recruited from sheltered accommodation and local activity groups. Forty volunteers were randomly selected and received 5 weeks of balance game training (5 males, 35 females; mean, 77.18 ± 6.59 years), whereas the remaining control participants recorded levels of physical activity (20 males, 22 females; mean, 76.62 ± 7.28 years). The effect of balance game training was measured on levels of functional balance and balance confidence in individuals with and without quantifiable balance impairments. RESULTS: Balance game training had a significant effect on levels of functional balance and balance confidence (P
Abstract.
Author URL.
Keune PM, Cocks AJ, Young WR, Burschka JM, Hansen S, Hofstadt-van Oy U, Oschmann P, Muenssinger J (2015). Dynamic walking features and improved walking performance in multiple sclerosis patients treated with fampridine (4-aminopyridine). BMC Neurology, 15(1).
Young WR, Mark Williams A (2015). How fear of falling can increase fall-risk in older adults: Applying psychological theory to practical observations. Gait & Posture, 41(1), 7-12.
Young W, Williams AM (2015). The multifaceted nature of fear of falling must be considered. The Journal of Physiology
2014
Young WR, Rodger MWM, Craig CM (2014). Auditory observation of stepping actions can cue both spatial and temporal components of gait in Parkinson's disease patients.
Neuropsychologia,
57(1), 140-153.
Abstract:
Auditory observation of stepping actions can cue both spatial and temporal components of gait in Parkinson's disease patients
Objectives: a common behavioural symptom of Parkinson[U+05F3]s disease (PD) is reduced step length (SL). Whilst sensory cueing strategies can be effective in increasing SL and reducing gait variability, current cueing strategies conveying spatial or temporal information are generally confined to the use of either visual or auditory cue modalities, respectively. We describe a novel cueing strategy using ecologically-valid 'action-related' sounds (footsteps on gravel) that convey both spatial and temporal parameters of a specific action within a single cue. Methods: the current study used a real-time imitation task to examine whether PD affects the ability to re-enact changes in spatial characteristics of stepping actions, based solely on auditory information. In a second experimental session, these procedures were repeated using synthesized sounds derived from recordings of the kinetic interactions between the foot and walking surface. A third experimental session examined whether adaptations observed when participants walked to action-sounds were preserved when participants imagined either real recorded or synthesized sounds. Results: Whilst healthy control participants were able to re-enact significant changes in SL in all cue conditions, these adaptations, in conjunction with reduced variability of SL were only observed in the PD group when walking to, or imagining the recorded sounds. Conclusions: the findings show that while recordings of stepping sounds convey action information to allow PD patients to re-enact and imagine spatial characteristics of gait, synthesis of sounds purely from gait kinetics is insufficient to evoke similar changes in behaviour, perhaps indicating that PD patients have a higher threshold to cue sensorimotor resonant responses. © 2014.
Abstract.
Bienkiewicz MMN, Young WR, Craig CM (2014). BALLS TO THE WALL: HOW ACOUSTIC INFORMATION FROM a BALL IN MOTION GUIDES INTERCEPTIVE MOVEMENT IN PEOPLE WITH PARKINSON'S DISEASE.
NEUROSCIENCE,
275, 508-518.
Author URL.
Rodger MWM, Young WR, Craig CM (2014). Synthesis of walking sounds for alleviating gait disturbances in Parkinson's disease.
IEEE Transactions on Neural Systems and Rehabilitation Engineering,
22(3), 543-548.
Abstract:
Synthesis of walking sounds for alleviating gait disturbances in Parkinson's disease
Managing gait disturbances in people with Parkinson's disease is a pressing challenge, as symptoms can contribute to injury and morbidity through an increased risk of falls. While drug-based interventions have limited efficacy in alleviating gait impairments, certain nonpharmacological methods, such as cueing, can also induce transient improvements to gait. The approach adopted here is to use computationally-generated sounds to help guide and improve walking actions. The first method described uses recordings of force data taken from the steps of a healthy adult which in turn were used to synthesize realistic gravel-footstep sounds that represented different spatio-temporal parameters of gait, such as step duration and step length. The second method described involves a novel method of sonifying, in real time, the swing phase of gait using real-time motion-capture data to control a sound synthesis engine. Both approaches explore how simple but rich auditory representations of action based events can be used by people with Parkinson's to guide and improve the quality of their walking, reducing the risk of falls and injury. Studies with Parkinson's disease patients are reported which show positive results for both techniques in reducing step length variability. Potential future directions for how these sound approaches can be used to manage gait disturbances in Parkinson's are also discussed. © 2014 IEEE.
Abstract.
Young WR (2014). We need a balanced perspective in Wii-search. Gait & Posture, 39(4), 1156-1157.
2013
Young W, Rodger M, Craig CM (2013). Perceiving and reenacting spatiotemporal characteristics of walking sounds.
Journal of Experimental Psychology: Human Perception and Performance,
39(2), 464-476.
Abstract:
Perceiving and reenacting spatiotemporal characteristics of walking sounds
Many studies have examined the processes involved in recognizing types of human action through sound, but little is known about whether the physical characteristics of an action (such as kinetic and kinematic parameters) can be perceived and imitated from sound. Twelve young healthy adults listened to recordings of footsteps on a gravel path taken from walks of different stride lengths (SL) and cadences. In 1 protocol, participants performed a real-time reenactment of the walking action depicted in a sound sample. Second, participants listened to 2 different sound samples and discriminated differences in SL. In a 2nd experiment, these procedures were repeated using synthesized sounds derived from the kinetic interactions between the foot and walking surface. A 3rd experiment examined the influence of altered cadence on participants' ability to discriminate changes in SL. Participants significantly adapted their own SL and cadence according to those depicted in both real and synthesized sounds (p <. 01). However, although participants accurately discriminated between large changes in SL, these perceptions were heavily influenced by temporal factors, that is, when cadence changed between samples. These findings show that spatial attributes of action sounds can be both mimicked and discriminated, even when only basic kinetic interactions present within the action are specified. © 2012 American Psychological Association.
Abstract.
Bieńkiewicz MMN, Rodger MWM, Young WR, Craig CM (2013). Time to get a move on: Overcoming bradykinetic movement in Parkinson's disease with artificial sensory guidance generated from biological motion.
Behavioural Brain Research,
253, 113-120.
Abstract:
Time to get a move on: Overcoming bradykinetic movement in Parkinson's disease with artificial sensory guidance generated from biological motion
Paradoxical kinesia describes the motor improvement in Parkinson's disease (PD) triggered by the presence of external sensory information relevant for the movement. This phenomenon has been puzzling scientists for over 60 years, both in neurological and motor control research, with the underpinning mechanism still being the subject of fierce debate. In this paper we present novel evidence supporting the idea that the key to understanding paradoxical kinesia lies in both spatial and temporal information conveyed by the cues and the coupling between perception and action. We tested a group of 7 idiopathic PD patients in an upper limb mediolateral movement task. Movements were performed with and without a visual point light display, travelling at 3 different speeds. The dynamic information presented in the visual point light display depicted three different movement speeds of the same amplitude performed by a healthy adult. The displays were tested and validated on a group of neurologically healthy participants before being tested on the PD group. Our data show that the temporal aspects of the movement (kinematics) in PD can be moderated by the prescribed temporal information presented in a dynamic environmental cue. Patients demonstrated a significant improvement in terms of movement time and peak velocity when executing movement in accordance with the information afforded by the point light display, compared to when the movement of the same amplitude and direction was performed without the display. In all patients we observed the effect of paradoxical kinesia, with a strong relationship between the perceptual information prescribed by the biological motion display and the observed motor performance of the patients. © 2013 Elsevier B.V.
Abstract.
2012
Young WR, Hollands MA (2012). Evidence for age-related decline in visuomotor function and reactive stepping adjustments.
Gait Posture,
36(3), 477-481.
Abstract:
Evidence for age-related decline in visuomotor function and reactive stepping adjustments.
This study investigated age-related and fall-risk-related differences in the ability to make visually guided reactive stepping adjustments during locomotion. Participants were asked to walk towards and step accurately onto a visual target which, during the step towards it, moved to an unpredictable location at an unpredictable time. We measured lower limb kinematics and eye movement characteristics of young adults and two groups of older adults deemed to be either at a low- or high-risk of falling. High-risk older adults produced significant deviations in foot trajectory with latencies of ∼300 ms, compared to 280 ms in low-risk older adults and ∼200 ms in young adults. Furthermore, high-risk older adults were unable to generate adjustments with the same magnitude and consistency as low-risk older adults and young adults. Saccadic reaction latencies also were doubled in high-risk older adults compared to young. Analysis of covariance showed that the significant between group differences in final foot placement error could be accounted for by differences in saccadic response times. We propose that age-related delays in visuomotor processing times may disrupt the timing and magnitude of stepping adjustments, possibly contributing to an increased likelihood of falls.
Abstract.
Author URL.
Young WR, Wing AM, Hollands MA (2012). Influences of state anxiety on gaze behavior and stepping accuracy in older adults during adaptive locomotion.
J Gerontol B Psychol Sci Soc Sci,
67(1), 43-51.
Abstract:
Influences of state anxiety on gaze behavior and stepping accuracy in older adults during adaptive locomotion.
OBJECTIVES: Older adults deemed to be at a high risk of falling transfer their gaze from a stepping target earlier than their low-risk counterparts. The extent of premature gaze transfer increases with task complexity and is associated with a decline in stepping accuracy. This study tests the hypothesis that increased anxiety about upcoming obstacles is associated with (a) premature transfers of gaze toward obstacles (i.e. looking away from a target box prior to completing the step on it in order to fixate future constraints in the walkway) and (b) reduced stepping accuracy on the target in older adults. METHODS: High-risk (9) and low-risk (8) older adult participants walked a 10-m pathway containing a stepping target area followed by various arrangements of obstacles, which varied with each trial. Anxiety, eye movements, and movement kinematics were measured. RESULTS: Progressively increasing task complexity resulted in associated statistically significant increases in measures of anxiety, extent of early gaze transfer, and stepping inaccuracies in the high-risk group. DISCUSSION: These results provide evidence that increased anxiety about environmental hazards is related to suboptimal visual sampling behavior which, in turn, negatively influences stepping performance, potentially contributing to increased falls risk in older adults.
Abstract.
Author URL.
Young WR, Hollands MA (2012). Newly acquired fear of falling leads to altered eye movement patterns and reduced stepping safety: a case study.
PLoS One,
7(11).
Abstract:
Newly acquired fear of falling leads to altered eye movement patterns and reduced stepping safety: a case study.
This opportune case study describes visual and stepping behaviours of an 87 year old female (P8), both prior to, and following two falls. Before falling, when asked to walk along a path containing two stepping guides positioned before and after an obstacle, P8 generally visually fixated the first stepping guide until after foot contact inside it. However, after falling P8 consistently looked away from the stepping guide before completing the step into it in order to fixate the upcoming obstacle in her path. The timing of gaze redirection away from the target (in relation to foot contact inside it) correlated with absolute stepping error. No differences in eyesight, cognitive function, or balance were found between pre- and post-fall recordings. However, P8 did report large increases in fall-related anxiety and reduced balance confidence, supporting previously suggested links between anxiety/increased fear or falling and maladaptive visual/stepping behaviours. The results represent a novel insight into how psychological and related behavioural factors can change in older adults following a fall, and provide a possible partial rationalisation for why recent fallers are more likely to fall again in the following 12 months. These findings highlight novel possibilities for falls prevention and rehabilitation.
Abstract.
Author URL.
Merriman NA, Whyatt C, Setti A, Gillian N, Young W, Ferguson S, Craig C, Newell FN (2012). The effect of balance training on audio–visual integration in older adults. Multisensory Research, 25(0), 155-155.
Young WR, Rodger MWM, Craig M (2012). Using ecological event-based acoustic guides to cue gait in Parkinson's disease patients.
Author URL.
2011
Young W, Ferguson S, Brault S, Craig C (2011). Assessing and training standing balance in older adults: a novel approach using the 'Nintendo Wii' Balance Board.
Gait Posture,
33(2), 303-305.
Abstract:
Assessing and training standing balance in older adults: a novel approach using the 'Nintendo Wii' Balance Board.
Older adults, deemed to be at a high risk of falling, are often unable to participate in dynamic exercises due to physical constraints and/or a fear of falling. Using the Nintendo 'Wii Balance Board' (WBB) (Nintendo, Kyoto, Japan), we have developed an interface that allows a user to accurately calculate a participant's centre of pressure (COP) and incorporate it into a virtual environment to create bespoke diagnostic or training programmes that exploit real-time visual feedback of current COP position. This platform allows researchers to design, control and validate tasks that both train and test balance function. This technology provides a safe, adaptable and low-cost balance training/testing solution for older adults, particularly those at high-risk of falling.
Abstract.
Author URL.
Thøgersen-Ntoumani C, Barkoukis V, Grano C, Lucidi F, Lindwall M, Liukkonen J, Raudsepp L, Young W (2011). Health and well-being profiles of older European adults. European Journal of Ageing, 8(2), 75-85.
2010
Young WR, Hollands MA (2010). Can telling older adults where to look reduce falls? Evidence for a causal link between inappropriate visual sampling and suboptimal stepping performance.
Exp Brain Res,
204(1), 103-113.
Abstract:
Can telling older adults where to look reduce falls? Evidence for a causal link between inappropriate visual sampling and suboptimal stepping performance.
Older adults at high risk of falling look away prematurely from targets they are stepping on in order to fixate future constraints in their walking path. This gaze behaviour is associated with decreased stepping accuracy and precision. The aims of the present study were to determine whether this apparently maladaptive gaze behaviour can be altered through intervention and to measure any corresponding improvements in stepping performance. Sixteen older adults, randomly placed into a control or intervention group, walked a 10-m path placing their feet into targets while their gaze direction and lower limb kinematics were measured. On average, both groups looked away from a stepping target around 100 ms prior to foot contact and the extent of early gaze transfer correlated with stepping errors. The participants returned on a separate day and repeated the experiment; however, the intervention group was instructed to maintain gaze on each target until heel contact. Following intervention, on average participants delayed gaze transfer from the first target until after heel contact and this change in behaviour resulted in a significant reduction in stepping errors. We propose that suboptimal visual sampling strategies contribute to the incidence of falls in the elderly.
Abstract.
Author URL.
