Publications by year
In Press
Harris D, Buckingham G, Wilson M, Brookes J, Mushtaq F, Mon-Williams M, Vine S (In Press). Exploring sensorimotor performance and user experience within a virtual reality golf putting simulator. Virtual Reality
Allen K, Harris D, Arthur T, Wood G, Buckingham G, Allen K (In Press). Investigating how Prior Knowledge Influences Perception and Action in Developmental Coordination Disorder. Quarterly Journal of Experimental Psychology
Arthur T, Vine S, Brosnan M, Buckingham G (In Press). Predictive Sensorimotor Control in. Autism. Brain: a journal of neurology
Bond B, Lester A, Buckingham G (In Press). The effects of partial sleep restriction and subsequent caffeine ingestion on neurovascular coupling.
Journal of Sleep ResearchAbstract:
The effects of partial sleep restriction and subsequent caffeine ingestion on neurovascular coupling
Habitual poor sleep is associated with cerebrovascular disease. Acute sleep deprivation alters the ability to match brain blood flow to metabolism (neurovascular coupling, NVC) but it is not known how partial sleep restriction affects NVC. When rested, caffeine disrupts NVC, but its effects in the sleep restricted state are unknown. The purpose of this study was therefore to investigate the effects of partial sleep restriction and subsequent caffeine ingestion on NVC.
Seventeen adults (age 27±5 years, 9 female) completed three separate overnight conditions with morning supplementation: habitual sleep plus placebo (Norm_Pl), habitual sleep plus caffeine (Norm_Caf), and partial (50% habitual sleep) restriction plus caffeine (PSR_Caf). NVC responses were quantified as blood velocity through the posterior (PCAv) and middle (MCAv) cerebral arteries using transcranial Doppler ultrasound during a visual search task and cognitive function tests, respectively. NVC was assessed the evening before and twice the morning after each sleep condition – pre- and 1-hour post caffeine ingestion.
NVC responses as a percent increase in PCAv and MCAv from resting baseline were not different at any timepoint, across all conditions (P>0.053). MCAv at baseline, and PCAv at baseline, peak, and total AUC were lower 1-hour after caffeine in both Norm_Caf and PSR_Caf as compared to Norm_Pl (P0.14).
In conclusion, NVC was unaltered after 50% sleep loss, and caffeine did not modify the magnitude of the response in the rested or sleep deprived state. Future research should explore how habitual poor sleep affects cerebrovascular function.
Abstract.
2023
Hassan EK, Jones AM, Buckingham G (2023). A novel protocol to induce mental fatigue.
Behavior Research MethodsAbstract:
A novel protocol to induce mental fatigue
AbstractMental fatigue is a commonplace human experience which is the focus of a growing body of research. Whilst researchers in numerous disciplines have attempted to uncover the origins, nature, and effects of mental fatigue, the literature is marked by many contradictory findings. We identified two major methodological problems for mental fatigue research. First, researchers rarely use objective measures of mental fatigue. Instead, they rely heavily on subjective reports as evidence that mental fatigue has been induced in participants. We aimed to develop a task which led to not only a subjective increase in mental fatigue, but a corresponding performance decrement in the mentally fatiguing task as an objective measure. Secondly, current mental fatigue paradigms have low ecological validity – in most prior studies participants have been fatigued with a single repetitive task such as the n-back or Stroop. To move towards a more ecologically valid paradigm, our participants undertook a battery of diverse cognitive tasks designed to challenge different aspects of executive function. The AX-CPT, n-back, mental rotation, and visual search tasks were chosen to challenge response inhibition, working memory, spatial reasoning, and attention. We report results from 45 participants aged 19 to 63 years who completed a two-hour battery comprising four different cognitive tasks. Subjective fatigue ratings and task performance were measured at the beginning and end of the battery. Our novel method resulted in an increase in subjective ratings of fatigue (p < 0.001) and a reduction in task performance (p = 0.008). Future research into mental fatigue may benefit from using this task battery.
Abstract.
Harris D, Arthur T, Buckingham G (2023). Does ‘virtuality’ affect the role of prior expectations in perception and action? Comparing predictive grip and lifting forces in real and virtual environments.
Abstract:
Does ‘virtuality’ affect the role of prior expectations in perception and action? Comparing predictive grip and lifting forces in real and virtual environments
Recent theories in cognitive science propose that prior expectations strongly influence how individuals perceive the world and control their actions. This influence is particularly relevant in novel sensory environments, such as virtual reality (VR). This registered report outlines a study examining the impact of VR on prediction-related sensory perception and motor control during object lifting. We aim to test two competing hypotheses: the Low-Precision Priors (LPP) hypothesis suggests reduced influence of prior expectations in VR due to the novelty and uncertainty of the context, while the High-Precision Priors (HPP) hypothesis posits increased reliance on predictions due to sensory uncertainty. We will employ weight illusion tasks (the size-weight and material-weight illusions) to isolate the effects of expectations on perception and action. We will also investigate the relationship between presence and predictive sensorimotor control, the way in which ‘virtuality’ affects motor learning, and how learning is transferred between physical reality and virtual environments. This research addresses crucial questions about how virtual environments impact predictive sensorimotor control and has implications for applications of VR technologies to training and rehabilitation.
Abstract.
Lester A (2023). Exploring the effects of acute partial sleep restriction and subsequent caffeine ingestion on neurovascular coupling and cognitive function.
Abstract:
Exploring the effects of acute partial sleep restriction and subsequent caffeine ingestion on neurovascular coupling and cognitive function
Longitudinal, cross-sectional, and acute experimental research demonstrate that a short sleep duration is associated with an increased risk of both cardiovascular and cerebrovascular disease. Chronic habitual short sleep duration is associated with an increased dementia risk, however a quarter of the population fail to meet sleep duration guidelines. It is thought that alterations in cerebrovascular function precede symptoms of cognitive decline and dementia. Currently, no evidence exists on measures of cerebrovascular function, such as neurovascular coupling (NVC), and habitual sleep across the lifespan. The association of chronic poor sleep and dementia is likely due to the repeated exposure to a poor night’s sleep. Therefore, there is value in performing controlled, interventional work to understand the acute responses to a single night of sleep restriction. Furthermore, following a night of poor sleep, individuals commonly consume caffeine to increase alertness, but caffeine is known to simultaneously reduce brain blood flow. It is unknown how caffeine affects cerebrovascular function in a sleep restricted state. The purpose of this thesis was therefore to explore 1) the impact of one night of partial sleep restriction on NVC and, 2) whether caffeine ingestion affects NVC after partial sleep restriction in young healthy adults. NVC was determined using transcranial Doppler ultrasound (TCD) to measure blood velocity through the posterior cerebral artery (PCAv) during a visual search task. TCD was also used to measure blood velocity through the middle cerebral artery (MCAv) during cognitive function tests, both of which were assessed before and after normal sleep and partial sleep restriction, and following caffeine ingestion. This study found that NVC was unaltered following partial sleep restriction, and that the magnitude of the NVC response was unchanged after caffeine ingestion in both the rested and sleep restricted state. However, both absolute PCAv and MCAv were lower after caffeine, though this response did not differ between normal and restricted sleep. This study was the first to examine the effects of partial sleep restriction and subsequent caffeine ingestion on a measure of cerebrovascular function. However, sleep restriction was only studied in the form of a 50% sleep restriction, with sleep taking place in the second half of the night. Future research should explore whether the relationship between sleep and NVC is dependent on how sleep is accrued throughout the night, for example fragmented/broken sleep.
Abstract.
Arthur T, Brosnan M, Harris D, Buckingham G, Wilson M, Williams G, Vine S (2023). Investigating how Explicit Contextual Cues Affect Predictive Sensorimotor Control in Autistic Adults.
J Autism Dev Disord,
53(11), 4368-4381.
Abstract:
Investigating how Explicit Contextual Cues Affect Predictive Sensorimotor Control in Autistic Adults.
Research suggests that sensorimotor difficulties in autism could be reduced by providing individuals with explicit contextual information. To test this, we examined autistic visuomotor control during a virtual racquetball task, in which participants hit normal and unexpectedly-bouncy balls using a handheld controller. The probability of facing each type of ball was varied unpredictably over time. However, during cued trials, participants received explicit information about the likelihood of facing each uncertain outcome. When compared to neurotypical controls, autistic individuals displayed poorer task performance, atypical gaze profiles, and more restricted swing kinematics. These visuomotor patterns were not significantly affected by contextual cues, indicating that autistic people exhibit underlying differences in how prior information and environmental uncertainty are dynamically modulated during movement tasks.
Abstract.
Author URL.
Mineiro J, Buckingham G (2023). O hand, where art thou? Mapping hand location across the visual field during common activities.
Experimental Brain Research,
241(5), 1227-1239.
Abstract:
O hand, where art thou? Mapping hand location across the visual field during common activities
Humans employ visually-guided actions during a myriad of daily activities. These ubiquitous but precise manual actions rely on synergistic work between eye and hand movements. During this close cooperation between hands and eyes, the hands persist in sight in a way which is unevenly distributed across our visual field. One common assertion is that most hand actions occur in the lower visual field (LVF) because the arms are anatomically lower than the head, and objects typically rest on waist-high table surfaces. While experimental work has shown that humans are more efficient at reaching for and grasping targets located below their visual midline (Goodale and Danckert, Exp Brain Res 137:303–308, 2001), there is almost no empirical data detailing where the hands lie in the visual fields during natural hand actions. To build a comprehensive picture of hand location during natural visually guided manual actions, we analyzed data from a large-scale open-access dataset containing 100 h of non-scripted manual object interactions during domestic kitchen tasks filmed from a head-mounted camera. We found a clear vertical visual asymmetry with hands located in the lower visual scene (LVS) in more than 70% of image frames, particularly in ipsilateral space. These findings provide the first direct evidence for the established assumption that hands spend more time in the lower than in the upper visual field (UVF). Further work is required to determine whether this LVF asymmetry differs across the lifespan, in different professions, and in clinical populations.
Abstract.
Arthur T, Vine S, Buckingham G, Brosnan M, Wilson M, Harris D (2023). Testing predictive coding theories of autism spectrum disorder using models of active inference.
PLoS Comput Biol,
19(9).
Abstract:
Testing predictive coding theories of autism spectrum disorder using models of active inference.
Several competing neuro-computational theories of autism have emerged from predictive coding models of the brain. To disentangle their subtly different predictions about the nature of atypicalities in autistic perception, we performed computational modelling of two sensorimotor tasks: the predictive use of manual gripping forces during object lifting and anticipatory eye movements during a naturalistic interception task. In contrast to some accounts, we found no evidence of chronic atypicalities in the use of priors or weighting of sensory information during object lifting. Differences in prior beliefs, rates of belief updating, and the precision weighting of prediction errors were, however, observed for anticipatory eye movements. Most notably, we observed autism-related difficulties in flexibly adapting learning rates in response to environmental change (i.e. volatility). These findings suggest that atypical encoding of precision and context-sensitive adjustments provide a better explanation of autistic perception than generic attenuation of priors or persistently high precision prediction errors. Our results did not, however, support previous suggestions that autistic people perceive their environment to be persistently volatile.
Abstract.
Author URL.
Alrashidi M, Wadey CA, Tomlinson RJ, Buckingham G, Williams CA (2023). The efficacy of virtual reality interventions compared with conventional physiotherapy in improving the upper limb motor function of children with cerebral palsy: a systematic review of randomised controlled trials.
Disabil Rehabil,
45(11), 1773-1783.
Abstract:
The efficacy of virtual reality interventions compared with conventional physiotherapy in improving the upper limb motor function of children with cerebral palsy: a systematic review of randomised controlled trials.
PURPOSE: Cerebral palsy (CP) is the commonest motor disability affecting children. This study reviewed the evidence for virtual reality (VR) intervention compared with conventional physiotherapy in upper limb function of children with CP. METHODS: Searches were undertaken in MEDLINE, EMBASE, PEDro, CENTRAL, Web of Science, CINAHL, ERIC, ICTRP, EU-CTR, ClinicalTrials.gov and EThOS databases. Only randomised-controlled trials (RCTs) were included. Two reviewers independently screened the search results, assessed full-text articles, extracted data and appraised the methodological quality by using the Cochrane collaboration's risk of bias (RoB2) tool. Albatross plots were used to synthesise the data. RESULTS: Seven RCTs, examining motor function in a total of 202 children with CP, included. Four trials used the Quality of Upper Extremity Skills Test (QUEST) as an outcome measure, and three trials used grip strength. These outcome measures were utilised to develop two Albatross plots. Data from the plots showed contradictory findings of the included studies. CONCLUSIONS: the effect of VR in the upper limb rehabilitation of children with CP remains unclear. All included studies used commercial non-immersive VR games. Future high-quality clinical research is needed to explore the extent to which non-immersive and immersive VR is feasible and effective with children and adolescents.IMPLICATIONS FOR REHABILITATIONThe current evidence supporting the use of VR as a rehabilitative tool is weak and uncertain.The current use of VR relies only on commercial non-immersive VR (off-shelf) games, which are not adjustable to meet the demands and goals of therapy programmes.Future research is needed to study the therapeutic feasibility of immersive VR with children and adolescents.
Abstract.
Author URL.
Evans JO, Tsaneva-Atanasova K, Buckingham G (2023). Using immersive virtual reality to remotely examine performance differences between dominant and non-dominant hands.
Virtual Reality,
27(3), 2211-2226.
Abstract:
Using immersive virtual reality to remotely examine performance differences between dominant and non-dominant hands
AbstractCircle drawing may be a useful task to study upper-limb function in patient populations. However, previous studies rely on expensive and bulky robotics to measure performance. For clinics or hospitals with limited budgets and space, this may be unfeasible. Virtual reality (VR) provides a portable and low-cost tool with integrated motion capture. It offers potentially a more feasible medium by which to assess upper-limb motor function. Prior to use with patient populations, it is important to validate and test the capabilities of VR with healthy users. This study examined whether a VR-based circle drawing task, completed remotely using participant’s own devices, could capture differences between movement kinematics of the dominant and non-dominant hands in healthy individuals. Participants (n = 47) traced the outline of a circle presented on their VR head-mounted displays with each hand, while the positions of the hand-held controllers were continuously recorded. Although there were no differences observed in the size or roundness of circles drawn with each hand, consistent with prior literature our results did show that the circles drawn with the dominant hand were completed faster than those with the non-dominant hand. This provides preliminary evidence that a VR-based circle drawing task may be a feasible method for detecting subtle differences in function in clinical populations.
Abstract.
2022
Buckingham G (2022). "I really enjoy the hectic multitude of jobs I get to complete in any one day". In (Ed)
Academia and the World Beyond: Navigating Life after a PhD, 161-169.
Abstract:
"I really enjoy the hectic multitude of jobs I get to complete in any one day"
Abstract.
Eaves DL, Hodges NJ, Buckingham G, Buccino G, Vogt S (2022). Enhancing motor imagery practice using synchronous action observation.
Psychological ResearchAbstract:
Enhancing motor imagery practice using synchronous action observation
In this paper, we discuss a variety of ways in which practising motor actions by means of motor imagery (MI) can be enhanced via synchronous action observation (AO), that is, by AO + MI. We review the available research on the (mostly facilitatory) behavioural effects of AO + MI practice in the early stages of skill acquisition, discuss possible theoretical explanations, and consider several issues related to the choice and presentation schedules of suitable models. We then discuss considerations related to AO + MI practice at advanced skill levels, including expertise effects, practical recommendations such as focussing attention on specific aspects of the observed action, using just-ahead models, and possible effects of the perspective in which the observed action is presented. In section “Coordinative AO + MI”, we consider scenarios where the observer imagines performing an action that complements or responds to the observed action, as a promising and yet under-researched application of AO + MI training. In section “The dual action simulation hypothesis of AO + MI”, we review the neurocognitive hypothesis that AO + MI practice involves two parallel action simulations, and we consider opportunities for future research based on recent neuroimaging work on parallel motor representations. In section “AO + MI training in motor rehabilitation”, we review applications of AO, MI, and AO + MI training in the field of neurorehabilitation. Taken together, this evidence-based, exploratory review opens a variety of avenues for future research and applications of AO + MI practice, highlighting several clear advantages over the approaches of purely AO- or MI-based practice.
Abstract.
Arthur T, Brosnan M, Harris D, Buckingham G, Wilson M, Williams G, Vine SJ (2022). Investigating how explicit contextual cues affect predictive sensorimotor control in autistic adults.
Abstract:
Investigating how explicit contextual cues affect predictive sensorimotor control in autistic adults.
Research suggests that sensorimotor difficulties in autism could be reduced by providing individuals with explicit contextual information. To test this, we examined autistic visuomotor control during a virtual racquetball task, in which participants hit normal and unexpectedly-bouncy balls using a handheld controller. The probability of facing each type of ball was varied unpredictably over time; however, during cued trials, participants received explicit information about the likelihood of facing each uncertain outcome. When compared to neurotypical controls, autistic individuals displayed poorer task performance, atypical gaze profiles, and more restricted swing kinematics. These visuomotor patterns were not significantly affected by contextual cues, indicating that autistic people exhibit underlying differences in how prior information and environmental uncertainty are dynamically modulated during movement tasks.
Abstract.
Arthur T (2022). Sensorimotor Differences in Autism Spectrum Disorder: an evaluation of potential mechanisms.
Abstract:
Sensorimotor Differences in Autism Spectrum Disorder: an evaluation of potential mechanisms.
This thesis examined the aetiology of sensorimotor impairments in Autism Spectrum Disorder: a neurodevelopmental condition that affects an individual’s socio-behavioural preferences, personal independence, and quality of life. Issues relating to clumsiness and movement coordination are common features of autism that contribute to wide-ranging daily living difficulties. However, these characteristics are relatively understudied and there is an absence of evidence-based practical interventions. To pave the way for new, scientifically-focused programmes, a series of studies investigated the mechanistic underpinnings of sensorimotor differences in autism. Following a targeted review of previous research, study one explored links between autistic-like traits and numerous conceptually-significant movement control functions. Eye-tracking analyses were integrated with force transducers and motion capture technology to examine how participants interacted with uncertain lifting objects. Upon identifying a link between autistic-like traits and context-sensitive predictive action control, study two replicated these procedures with a sample of clinically-diagnosed participants. Results illustrated that autistic people are able to use predictions to guide object interactions, but that uncertainty-related adjustments in sensorimotor integration are atypical. Such findings were advanced within a novel virtual-reality paradigm in study three, which systematically manipulated environmental uncertainty during naturalistic interception actions. Here, data supported proposals that precision weighting functions are aberrant in autistic people, and suggested that these individuals have difficulties with processing volatile sensory information. These difficulties were not alleviated by the experimental provision of explicit contextual cues in study four. Together, these studies implicate the role of implicit neuromodulatory mechanisms that regulate dynamic sensorimotor behaviours. Results support the development of evidence-based programmes that ‘make the world more predictable’ for autistic people, with various theoretical and practical implications presented. Possible applications of these findings are discussed in relation to recent multi-disciplinary research and conceptual advances in the field, which could help improve daily living skills and functional quality of life.
Abstract.
Bahceci O, Pena-Rios A, Buckingham G, Conway A (2022). Supervised Machine Learning Hand Gesture Classification in VR for Immersive Training.
Abstract:
Supervised Machine Learning Hand Gesture Classification in VR for Immersive Training
Abstract.
Arthur T, Vine SJ, Buckingham G, Brosnan M, Wilson M, Harris D (2022). Testing predictive coding theories of autism spectrum disorder using models of active inference.
Abstract:
Testing predictive coding theories of autism spectrum disorder using models of active inference
Several competing neuro-computational theories of autism have emerged from predictive coding models of the brain. These accounts have a common focus on the relationship between prior beliefs and sensory inputs as a mechanism for explaining key features of autism, yet they differ in exactly how they characterise atypicalities in perception and action. We tested these competing predictions using computational modelling of two datasets that allowed us to probe both visual and motor aspects of active inference: manual gripping forces during object lifting and anticipatory eye movements during a naturalistic interception task. We compared estimated belief trajectories between autistic and neurotypical individuals to determine the underlying differences in active inference. We found no evidence of chronic deficits in the use of priors or weighting of sensory information during object lifting. Differences in prior beliefs, rates of belief updating, and the precision weighting of prediction errors were, however, observed for anticipatory eye movements. Notably, we observed autism-related difficulties in flexibly adapting learning rates in response to environmental change (i.e. volatility). These findings suggest that aberrant encoding of precision and context-sensitive adjustments provide a better explanation of autistic perception than generic attenuation of priors or persistently high precision prediction errors.
Abstract.
van Polanen V, Buckingham G, Davare M (2022). The effects of TMS over the anterior intraparietal area on anticipatory fingertip force scaling and the size-weight illusion.
J Neurophysiol,
128(2), 290-301.
Abstract:
The effects of TMS over the anterior intraparietal area on anticipatory fingertip force scaling and the size-weight illusion.
When lifting an object skillfully, fingertip forces need to be carefully scaled to the object's weight, which can be inferred from its apparent size and material. This anticipatory force scaling ensures smooth and efficient lifting movements. However, even with accurate motor plans, weight perception can still be biased. In the size-weight illusion, objects of different size but equal weight are perceived to differ in heaviness, with the small object perceived to be heavier than the large object. The neural underpinnings of anticipatory force scaling to object size and the size-weight illusion are largely unknown. In this study, we tested the role of anterior intraparietal cortex (aIPS) in predictive force scaling and the size-weight illusion, by applying continuous theta burst stimulation (cTBS) prior to participants lifting objects of different sizes. Participants received cTBS over aIPS, the primary motor cortex (control area), or Sham stimulation. We found no evidence that aIPS stimulation affected the size-weight illusion. Effects were, however, found on anticipatory force scaling, where grip force was less tuned to object size during initial lifts. These findings suggest that aIPS is not involved in the perception of object weight but plays a transient role in the sensorimotor predictions related to object size. NEW & NOTEWORTHY Skilled object manipulation requires forming anticipatory motor plans according to the object's properties. Here, we demonstrate the role of anterior intraparietal sulcus (aIPS) in anticipatory grip force scaling to object size, particularly during initial lifting experience. Interestingly, this role was not maintained after continued practice and was not related to perceptual judgments measured with the size-weight illusion.
Abstract.
Author URL.
Vittersø AD, Halicka M, Buckingham G, Proulx MJ, Bultitude JH (2022). The sensorimotor theory of pathological pain revisited.
Neurosci Biobehav Rev,
139Abstract:
The sensorimotor theory of pathological pain revisited.
Harris (1999) proposed that pain can arise in the absence of tissue damage because changes in the cortical representation of the painful body part lead to incongruences between motor intention and sensory feedback. This idea, subsequently termed the sensorimotor theory of pain, has formed the basis for novel treatments for pathological pain. Here we review the evidence that people with pathological pain have changes to processes contributing to sensorimotor function: motor function, sensory feedback, cognitive representations of the body and its surrounding space, multisensory processing, and sensorimotor integration. Changes to sensorimotor processing are most evident in the form of motor deficits, sensory changes, and body representations distortions, and for Complex Regional Pain Syndrome (CRPS), fibromyalgia, and low back pain. Many sensorimotor changes are related to cortical processing, pain, and other clinical characteristics. However, there is very limited evidence that changes in sensorimotor processing actually lead to pain. We therefore propose that the theory is more appropriate for understanding why pain persists rather than how it arises.
Abstract.
Author URL.
Chinzara TT, Buckingham G, Harris DJ (2022). Transcranial direct current stimulation and sporting performance: a systematic review and meta-analysis of transcranial direct current stimulation effects on physical endurance, muscular strength and visuomotor skills.
Eur J Neurosci,
55(2), 468-486.
Abstract:
Transcranial direct current stimulation and sporting performance: a systematic review and meta-analysis of transcranial direct current stimulation effects on physical endurance, muscular strength and visuomotor skills.
Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that has been linked with a range of physiological and cognitive enhancements relevant to sporting performance. As a number of positive and null findings have been reported in the literature, the present meta-analysis sought to synthesise results across endurance, strength and visuomotor skill domains to investigate if tDCS improves any aspect of sporting performance. Online database searches in August 2020 identified 43 full-text studies which examined the acute effects of tDCS compared to sham/control conditions on physical endurance, muscular strength, and visuomotor skills in healthy adults. Meta-analysis indicated a small overall effect favouring tDCS stimulation over sham/control (standardized mean difference (SMD) = 0.25, CI95%[.14;.36]). Effects on strength (SMD = 0.31, CI95%[.10;.51]) and visuomotor (SMD = 0.29, CI95%[.00;.57]) tasks were larger than endurance performance (SMD = 0.18, CI95%[.00;.37]). Meta-regressions indicated effect sizes were not related to stimulation parameters, but other factors such as genetics, gender, and experience may modulate tDCS effects. The results suggest tDCS has the potential to be used as an ergogenic aid in conjunction with a specified training regime.
Abstract.
Author URL.
Naylor CE, Proulx MJ, Buckingham G (2022). Using Immersive Virtual Reality to Examine How Visual and Tactile Cues Drive the Material-Weight Illusion.
Atten Percept Psychophys,
84(2), 509-518.
Abstract:
Using Immersive Virtual Reality to Examine How Visual and Tactile Cues Drive the Material-Weight Illusion.
The material-weight illusion (MWI) demonstrates how our past experience with material and weight can create expectations that influence the perceived heaviness of an object. Here we used mixed-reality to place touch and vision in conflict, to investigate whether the modality through which materials are presented to a lifter could influence the top-down perceptual processes driving the MWI. University students lifted equally-weighted polystyrene, cork and granite cubes whilst viewing computer-generated images of the cubes in virtual reality (VR). This allowed the visual and tactile material cues to be altered, whilst all other object properties were kept constant. Representation of the objects' material in VR was manipulated to create four sensory conditions: visual-tactile matched, visual-tactile mismatched, visual differences only and tactile differences only. A robust MWI was induced across all sensory conditions, whereby the polystyrene object felt heavier than the granite object. The strength of the MWI differed across conditions, with tactile material cues having a stronger influence on perceived heaviness than visual material cues. We discuss how these results suggest a mechanism whereby multisensory integration directly impacts how top-down processes shape perception.
Abstract.
Author URL.
2021
Arthur T, Harris D, Buckingham G, Brosnan M, Wilson M, Williams G, Vine S (2021). An examination of active inference in autistic adults using immersive virtual reality.
Sci Rep,
11(1).
Abstract:
An examination of active inference in autistic adults using immersive virtual reality.
The integration of prior expectations, sensory information, and environmental volatility is proposed to be atypical in Autism Spectrum Disorder, yet few studies have tested these predictive processes in active movement tasks. To address this gap in the research, we used an immersive virtual-reality racquetball paradigm to explore how visual sampling behaviours and movement kinematics are adjusted in relation to unexpected, uncertain, and volatile changes in environmental statistics. We found that prior expectations concerning ball 'bounciness' affected sensorimotor control in both autistic and neurotypical participants, with all individuals using prediction-driven gaze strategies to track the virtual ball. However, autistic participants showed substantial differences in visuomotor behaviour when environmental conditions were more volatile. Specifically, uncertainty-related performance difficulties in these conditions were accompanied by atypical movement kinematics and visual sampling responses. Results support proposals that autistic people overestimate the volatility of sensory environments, and suggest that context-sensitive differences in active inference could explain a range of movement-related difficulties in autism.
Abstract.
Author URL.
Vittersø AD, Buckingham G, Ten Brink AF, Halicka M, Proulx MJ, Bultitude JH (2021). Characterising sensorimotor adaptation in Complex Regional Pain Syndrome.
Cortex,
140, 157-178.
Abstract:
Characterising sensorimotor adaptation in Complex Regional Pain Syndrome
It has been suggested that sensorimotor conflict contributes to the maintenance of some pathological pain conditions, implying that there are problems with the adaptation processes that normally resolve such conflict. We tested whether sensorimotor adaptation is impaired in people with Complex Regional Pain Syndrome (CRPS) by characterising their adaption to lateral prismatic shifts in vision. People with unilateral upper-limb CRPS Type I (n = 17), and pain-free individuals (n = 18; matched for age, sex, and handedness) completed prism adaptation with their affected/non-dominant and non-affected/dominant arms. We examined 1) the rate at which participants compensated for the optical shift during prism exposure (i.e. strategic recalibration), 2) endpoint errors made directly after prism adaptation (sensorimotor realignment) and the retention of these errors, and 3) kinematic markers associated with strategic control. Direct comparisons between people with CRPS and controls revealed no evidence of any differences in strategic recalibration, including no evidence for differences in a kinematic marker associated with trial-by-trial changes in movement plans during prism exposure. All participants made significant endpoint errors after prism adaptation exposure, indicative of sensorimotor realignment. Overall, the magnitude of this realignment did not differ between people with CRPS and pain-free controls. However, when endpoint errors were considered separately for each hand, people with CRPS made greater errors (indicating more rather than less realignment) when using their affected hand than their non-affected hand. No such difference was seen in controls. Taken together, these findings provide no evidence of impaired strategic control or sensorimotor realignment in people with CRPS. In contrast, they provide some indication that there could be a greater propensity for sensorimotor realignment in the CRPS-affected arm, consistent with more flexible representations of the body and peripersonal space. Our study challenges an implicit assumption of the theory that sensorimotor conflict might underlie some pathological pain conditions.
Abstract.
Rohrbach N, Hermsdoerfer J, Huber L-M, Thierfelder A, Buckingham G (2021). Fooling the size-weight illusion-Using augmented reality to eliminate the effect of size on perceptions of heaviness and sensorimotor prediction.
VIRTUAL REALITY,
25(4), 1061-1070.
Author URL.
Buckingham G (2021). Hand tracking for immersive virtual reality: opportunities and. challenges.
Abstract:
Hand tracking for immersive virtual reality: opportunities and. challenges
Hand tracking has become an integral feature of recent generations of
immersive virtual reality head-mounted displays. With the widespread adoption
of this feature, hardware engineers and software developers are faced with an
exciting array of opportunities and a number of challenges, mostly in relation
to the human user. In this article, I outline what I see as the main
possibilities for hand tracking to add value to immersive virtual reality as
well as some of the potential challenges in the context of the psychology and
neuroscience of the human user. It is hoped that this paper serves as a roadmap
for the development of best practices in the field for the development of
subsequent generations of hand tracking and virtual reality technologies.
Abstract.
Author URL.
Vittersø AD, Buckingham G, Ten Brink AF, Halicka M, Proulx MJ, Bultitude JH (2021). Normal manual straight ahead pointing in Complex Regional Pain Syndrome.
PLoS One,
16(12).
Abstract:
Normal manual straight ahead pointing in Complex Regional Pain Syndrome.
There is evidence to suggest that people with Complex Regional Pain Syndrome (CRPS) can have altered body representations and spatial cognition. One way of studying these cognitive functions is through manual straight ahead (MSA) pointing, in which participants are required to point straight ahead of their perceived body midline without visual feedback of the hand. We therefore compared endpoint errors from MSA pointing between people with CRPS (n = 17) and matched controls (n = 18), and examined the effect of the arm used (Side of Body; affected/non-dominant, non-affected/dominant). For all participants, pointing errors were biased towards the hand being used. We found moderate evidence of no difference between Groups on endpoint errors, and moderate evidence of no interaction with Side of Body. The differences in variability between Groups were non-significant/inconclusive. Correlational analyses showed no evidence of a relationship between MSA endpoint errors and clinical parameters (e.g. CRPS severity, duration, pain) or questionnaire measures (e.g. body representation, "neglect-like symptoms", upper limb disability). This study is consistent with earlier findings of no difference between people with CRPS and controls on MSA endpoint errors, and is the first to provide statistical evidence of similar performance of these two groups. Our results do not support a relationship between clinical or self-reported measures (e.g. "neglect-like symptoms") and any directional biases in MSA. Our findings may have implications for understanding neurocognitive changes in CRPS.
Abstract.
Author URL.
Naylor CE, Harris D, Vine SJ, Brookes J, Mushtaq F, Buckingham G (2021). The Integration of Tactile and Visual Cues Increases Golf Putting Error in a Mixed-Reality Paradigm.
Mathew RK, Mushtaq F, Ahmed S, Ahmed K, Anderton LK, Arnab S, Awais M, Badger JR, Bajwa KS, Baraas RC, et al (2021). Three principles for the progress of immersive technologies in healthcare training and education. BMJ Simulation and Technology Enhanced Learning, 7(5), 459-460.
Chinzara TT, Buckingham G, Harris D (2021). Transcranial direct current stimulation and sporting performance: a systematic review and meta‐analysis of transcranial direct current stimulation effects on physical endurance, muscular strength and visuomotor skills.
Abstract:
Transcranial direct current stimulation and sporting performance: a systematic review and meta‐analysis of transcranial direct current stimulation effects on physical endurance, muscular strength and visuomotor skills
Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that has been linked with a range of physiological and cognitive enhancements relevant to sporting performance. As a number of positive and null findings have been reported in the literature, the present meta-analysis sought to synthesise results across endurance, strength and visuomotor skill domains to investigate if tDCS improves any aspect of sporting performance. Online database searches in August 2020 identified 43 full-text studies which examined the acute effects of tDCS compared to sham/control conditions on physical endurance, muscular strength and visuomotor skills in healthy adults. The quantitative analysis indicated a small overall effect favouring tDCS stimulation over sham/control (SMD=0.25, CI95%[0.14;0.36]). Effects on strength (SMD=0.31, CI95%[0.10;0.51]) and visuomotor (SMD=0.29, CI95%[0.00;0.57]) tasks were larger than endurance performance (SMD=0.18, CI95%[0.00;0.37]). Meta-regressions indicated effect sizes were not related to stimulation parameters, but genetics, gender, and experience may modulate tDCS effects. The results suggest tDCS has the potential to be used as an ergogenic aid in conjunction with a specified training regime.
Abstract.
Arthur T, Harris D, Allen K, Naylor C, Wood G, Vine S, Wilson M, Tsaneva-Atanasova K, Buckingham G (2021). Visuo-motor attention during object interaction in children with developmental coordination disorder.
CortexAbstract:
Visuo-motor attention during object interaction in children with developmental coordination disorder
Developmental coordination disorder (DCD) describes a condition of poor motor performance in the absence of intellectual impairment. Despite being one of the most prevalent developmental disorders, little is known about how fundamental visuomotor processes might function in this group. One prevalent idea is children with DCD interact with their environment in a less predictive fashion than typically developing children. A metric of prediction which has not been examined in this group is the degree to which the hands and eyes are coordinated when performing manual tasks. To this end, we examined hand and eye movements during an object lifting task in a group of children with DCD (n=19) and an age-matched group of children without DCD (n=39). We observed no differences between the groups in terms of how well they coordinated their hands and eyes when lifting objects, nor in terms of the degree by which the eye led the hand. We thus find no evidence to support the proposition that children with DCD coordinate their hands and eyes in a non-predictive fashion. In a follow-up exploratory analysis we did, however, note differences in fundamental patterns of eye movements between the groups, with children in the DCD group showing some evidence of atypical visual sampling strategies and gaze anchoring behaviours during the task.
Abstract.
Author URL.
2020
Vittersø AD, Buckingham G, Halicka M, Proulx MJ, Bultitude JH (2020). Altered updating of bodily and spatial representations after tool-use in complex regional pain syndrome.
Pain,
161(7), 1609-1628.
Abstract:
Altered updating of bodily and spatial representations after tool-use in complex regional pain syndrome.
Distorted representations of the body and peripersonal space are common in complex regional pain syndrome (CRPS), and might modulate its symptoms (eg, asymmetric limb temperature). In pain-free people, such representations are malleable, and update when we interact with objects in our environment (eg, during tool-use). Distortions are also common after immobilisation, but quickly normalise once movement is regained. We tested the hypothesis that people with CRPS have problems updating bodily and spatial representations, which contributes to the maintenance of their distorted representations by preventing normalization. We also explored spatially defined modulations of hand temperature asymmetries, and any influence of updating bodily and spatial representations on this effect. Thirty-six people with unilateral CRPS (18 upper limb and 18 lower limb) and 36 pain-free controls completed tool-use tasks considered to alter body and peripersonal space representations (measured using tactile distance judgements and a visuotactile crossmodal congruency task, respectively). We also tested how the arrangement (crossed and uncrossed) of the hands and tools affected hand temperature. In upper-limb CRPS, the nonaffected arm representation updated normally, but the affected arm representation updated in the opposite to normal direction. A similar pattern was seen in lower-limb CRPS, although not significant. Furthermore, people with CRPS showed more pronounced updating of peripersonal space than the controls. We did not observe any modulation of hand temperature asymmetries by the arrangement of hands or tools. Our findings show enhanced malleability of bodily and spatial representations in CRPS, which may suggest that central mechanisms are altered in this condition.
Abstract.
Author URL.
Arthur T, Harris D, Buckingham G, Brosnan M, Wilson M, Williams G, Vine SJ (2020). An examination of active inference in autistic adults using immersive virtual reality.
Abstract:
An examination of active inference in autistic adults using immersive virtual reality.
The integration of prior expectations, sensory information, and environmental volatility is proposed to be atypical in Autism Spectrum Disorder, yet few studies have tested these predictive processes in active movement tasks. We used an immersive virtual-reality racquetball paradigm to explore how visual sampling behaviours and movement kinematics are adjusted in relation to unexpected, uncertain, and volatile changes in environmental statistics. We found that prior expectations concerning ball ‘bounciness’ affected sensorimotor control in both autistic and neurotypical participants, with all individuals using prediction-driven gaze strategies to track the virtual ball. However, autistic participants showed substantial differences in visuomotor behaviour when environmental conditions were more volatile. Specifically, uncertainty-related performance difficulties in these conditions were accompanied by atypical movement kinematics and visual sampling behaviours. Results support proposals that autistic people overestimate the volatility of sensory environments, and suggest that context-sensitive differences in active inference could explain a range of movement-related difficulties in autism.
Abstract.
Chinzara T, Buckingham G (2020). Does transcranial direct current stimulation (tDCS) improve sport performance? a systematic review and Meta-analysis.
Whitwell RL, Sperandio I, Buckingham G, Chouinard PA, Goodale MA (2020). Erratum: Grip Constancy but Not Perceptual Size Constancy Survives Lesions of Early Visual Cortex (Current Biology (2020) 30(18) (3680–3686.e5), (S0960982220310186), (10.1016/j.cub.2020.07.026)).
Current Biology,
30(18), 3700-3701.
Abstract:
Erratum: Grip Constancy but Not Perceptual Size Constancy Survives Lesions of Early Visual Cortex (Current Biology (2020) 30(18) (3680–3686.e5), (S0960982220310186), (10.1016/j.cub.2020.07.026))
(Current Biology 30, 3680–3686.e1–e5; September 21, 2020) in the original Figure 3, the bottom two images were mislabeled as “7.1 cm 6.2 cm 5.5 cm 5 cm.” They should read as follows: 7.6 cm 6.3 cm 5.0 cm 3.8 cm, respectively. This has been corrected online and appears below. The authors apologize for any confusion the error may have caused. [Figure presented] [Figure presented]
Abstract.
Naylor CE, Power TJ, Buckingham G (2020). Examining Whether Semantic Cues can Affect Felt Heaviness When Lifting Novel Objects.
J Cogn,
3(1).
Abstract:
Examining Whether Semantic Cues can Affect Felt Heaviness When Lifting Novel Objects.
It is well established that manipulations of low-level stimulus properties unrelated to mass can impact perception of heaviness, the most famous example being the size-weight illusion whereby small objects feel heavier than equally-weighted larger objects. Interestingly, manipulations of high-level cues such as material have also induced weight illusions, highlighting that cognitive expectations alone are enough to create illusory weight differences. Less is known, however, about what type of cognitive expectations can influence perception of heaviness. As labels are often used to signify the heaviness of objects, this study examined whether semantic cues could induce a novel weight illusion. Participants lifted equally-sized and equally-weighted sets of objects labelled as 'light' and 'heavy' and reported their perceived heaviness both prior to and after lifting. Fingertip forces were also measured to understand how semantic cues may influence sensorimotor prediction. The labels clearly affected pre-lift-off expectations of heaviness. By contrast, we found no effect of these labels on the perceived heaviness of objects, nor on the forces used to grip and lift them on early trials. In other words, we find no evidence that semantic cues affect perception or action enough to induce a novel weight illusion. These findings suggest that the explicit expectations created by the labels did not dominate the implicit expectations created by the equal sizes of the objects, highlighting the segregated nature of cognitive expectations and their variable influences on perception and action.
Abstract.
Author URL.
Whitwell RL, Sperandio I, Buckingham G, Chouinard PA, Goodale MA (2020). Grip Constancy but Not Perceptual Size Constancy Survives Lesions of Early Visual Cortex.
Curr Biol,
30(18), 3680-3686.e5.
Abstract:
Grip Constancy but Not Perceptual Size Constancy Survives Lesions of Early Visual Cortex.
Object constancies are central constructs in theories of visual phenomenology. A powerful example is "size constancy," in which the perceived size of an object remains stable despite changes in viewing distance [1-4]. Evidence from neuropsychology [5], neuroimaging [6-11], transcranial magnetic stimulation [12, 13], single-unit and lesion studies in monkey [14-20], and computational modeling [21] suggests that re-entrant processes involving reciprocal interactions between primary visual cortex (V1) and extrastriate visual areas [22-26] play an essential role in mediating size constancy. It is seldom appreciated, however, that object constancies must also operate for the visual guidance of goal-directed action. For example, when reaching out to pick up an object, the hand's in-flight aperture scales with size of the goal object [27-30] and is refractory to the decrease in retinal-image size with increased viewing distance [31-41] (Figure 1), a phenomenon we call "grip constancy." Does grip constancy, like perceptual constancy, depend on V1 or can it be mediated by pathways that bypass it altogether? We tested these possibilities in an individual, M.C. who has bilateral lesions encompassing V1 and much of the ventral visual stream. We show that her perceptual estimates of object size co-vary with retinal-image size rather than real-world size as viewing distance varies. In contrast, M.C. shows near-normal scaling of in-flight grasp aperture to object size despite changes in viewing distance. Thus, although early visual cortex is necessary for perceptual object constancy, it is unnecessary for grip constancy, which is mediated instead by separate visual inputs to dorsal-stream visuomotor areas [42-48].
Abstract.
Author URL.
Harris DJ, Buckingham G, Wilson MR, Brookes J, Mushtaq F, Mon-Williams M, Vine SJ (2020). The effect of a virtual reality environment on gaze behaviour and motor skill learning. Psychology of Sport and Exercise, 50, 101721-101721.
Hassan EK, Sedda A, Buckingham G, McIntosh RD (2020). The size-weight illusion in visual form agnosic patient DF.
Neurocase,
26(5), 277-284.
Abstract:
The size-weight illusion in visual form agnosic patient DF.
The size-weight illusion is a perceptual illusion where smaller objects are judged as heavier than equally weighted larger objects. A previous informal report suggests that visual form agnosic patient DF does not experience the size-weight illusion when vision is the only available cue to object size. We tested this experimentally, comparing the magnitudes of DF's visual, kinesthetic and visual-kinesthetic size-weight illusions to those of 28 similarly-aged controls. A modified t-test found that DF's visual size-weight illusion was significantly smaller than that of controls (zcc = -1.7). A test of simple dissociation based on the Revised Standardized Difference Test found that the discrepancy between the magnitude of DF's visual and kinesthetic size-weight illusions was not significantly different from that of controls (zdcc = -1.054), thereby failing to establish a dissociation between the visual and kinesthetic conditions. These results are consistent with previous suggestions that visual form agnosia, following ventral visual stream damage, is associated with an abnormally reduced size-weight illusion. The results, however, do not confirm that this reduction is specific to the use of visual size cues to predict object weight, rather than reflecting more general changes in the processing of object size cues or in the use of predictive strategies for lifting.
Abstract.
Author URL.
Schneider TR, Buckingham G, Hermsdörfer J (2020). Visual cues, expectations, and sensorimotor memories in the prediction and perception of object dynamics during manipulation.
Exp Brain Res,
238(2), 395-409.
Abstract:
Visual cues, expectations, and sensorimotor memories in the prediction and perception of object dynamics during manipulation.
When we grasp and lift novel objects, we rely on visual cues and sensorimotor memories to predictively scale our finger forces and exert compensatory torques according to object properties. Recently, it was shown that object appearance, previous force scaling errors, and previous torque compensation errors strongly impact our percept. However, the influence of visual geometric cues on the perception of object torques and weights in a grasp to lift task is poorly understood. Moreover, little is known about how visual cues, prior expectations, sensory feedback, and sensorimotor memories are integrated for anticipatory torque control and object perception. Here, 12 young and 12 elderly participants repeatedly grasped and lifted an object while trying to prevent object tilt. Before each trial, we randomly repositioned both the object handle, providing a geometric cue on the upcoming torque, as well as a hidden weight, adding an unforeseeable torque variation. Before lifting, subjects indicated their torque expectations, as well as reporting their experience of torque and weight after each lift. Mixed-effect multiple regression models showed that visual shape cues governed anticipatory torque compensation, whereas sensorimotor memories played less of a role. In contrast, the external torque and committed compensation errors at lift-off mainly determined how object torques and weight were perceived. The modest effect of handle position differed for torque and weight perception. Explicit torque expectations were also correlated with anticipatory torque compensation and torque perception. Our main findings generalized across both age groups. Our results suggest distinct weighting of inputs for action and perception according to reliability.
Abstract.
Author URL.
2019
Saccone EJ, Goldsmith RM, Buckingham G, Chouinard PA (2019). Container size exerts a stronger influence than liquid volume on the perceived weight of objects.
Cognition,
192Abstract:
Container size exerts a stronger influence than liquid volume on the perceived weight of objects.
Many features of an object can influence how we predict and perceive its weight. The current study evaluated the relative contributions of sensory and conceptual processing of object features on weight perception. We employed a novel paradigm to investigate how container size and the amount of liquid inside can influence the perceived weight of bottles and the forces deployed when lifting them. Stimulus pairs always had the same mass but could vary in liquid volume (full vs half-full bottle) or size (large vs small bottle; size-weight illusion (SWI)). In Experiment 1, participants lifted the stimuli via strings, which served to isolate the influence of visual from kinaesthetic information about the size of stimuli on perception and lifting behaviour. In Experiment 2, participants lifted the stimuli via handles that were attached directly to the objects. This lifting style is more likely to include deviations from true vertical lifting, which should theoretically provide more kinaesthetic information about the size of the stimuli. Experiment 1 did not produce any weight illusion. Experiment 2 produced a weight illusion but only when container size differed. Thus, liquid volume did not influence perceived weight when container size was held constant in either experiment. Curiously, additional control experiments revealed that participants could not discriminate between the different sized bottles solely from the kinaesthetic information received from a handle-based lift, suggesting that size might be processed differently when making explicit perceptual judgements about it than when influencing weight perception. Together, these findings suggest that weight illusions are driven more strongly by the kinaesthetic processing of stimulus features than predictions arising from conceptual weight cues.
Abstract.
Author URL.
Buckingham G (2019). Examining the size-weight illusion with visuo-haptic conflict in immersive virtual reality.
Q J Exp Psychol (Hove),
72(9), 2168-2175.
Abstract:
Examining the size-weight illusion with visuo-haptic conflict in immersive virtual reality.
When we experience our environment, we do so by combining sensory inputs with expectations derived from our prior knowledge, which can lead to surprising perceptual effects such as small objects feeling heavier than equally weighted large objects (the size-weight illusion (SWI)). Interestingly, there is evidence that the way in which the volume of an object is experienced can affect the strength of the illusion, with a SWI induced by exclusively haptic volume cues feeling stronger than a SWI induced with only visual volume cues. Furthermore, visual cues appear to add nothing over and above haptic size cues in terms of the strength of the induced weight illusion-findings which are difficult to reconcile with work using cue-conflict paradigms where visual cues usually dominate haptic cues. Here, virtual reality was used to place these senses in conflict with one another. Participants (N = 22) judged the heaviness of identically weighted cylinders across three conditions: (1) objects appeared different sizes but were physically the same size, (2) objects were physically different sizes but appeared to be the same size, or (3) objects which looked and felt different sizes from one another. Consistent with prior work, haptic size cues induced a larger SWI than that induced by visual size differences. In contrast to prior work, however, congruent vision and haptic size cues yielded a larger still SWI. These findings not only add to our understanding of how different modalities combine to influence our hedonic perception but also showcase how virtual reality can develop novel cue-conflict paradigms.
Abstract.
Author URL.
Vittersø AD, Halicka M, Buckingham G, Proulx MJ, Bultitude JH (2019). Experimentally induced pain does not influence updating of peripersonal space and body representations following tool-use.
PLoS One,
14(5).
Abstract:
Experimentally induced pain does not influence updating of peripersonal space and body representations following tool-use.
Representations of the body and peripersonal space can be distorted for people with some chronic pain conditions. Experimental pain induction can give rise to similar, but transient distortions in healthy individuals. However, spatial and bodily representations are dynamic, and constantly update as we interact with objects in our environment. It is unclear whether induced pain disrupts the mechanisms involved in updating these representations. In the present study, we sought to investigate the effect of induced pain on the updating of peripersonal space and body representations during and following tool-use. We compared performance under three conditions (pain, active placebo, neutral) on a visuotactile crossmodal congruency task and a tactile distance judgement task to measure updating of peripersonal space and body representations, respectively. Consistent with previous findings, the difference in crossmodal interference from visual distractors in the same compared to opposite visual field to the tactile target was less when tools were crossed than uncrossed. This suggests an extension of peripersonal space to incorporate the tips of the tools. Also consistent with previous findings, estimates of the felt tactile distance judgements decreased after active tool-use. In contrast to our predictions, however, we found no evidence that pain interfered with performance on either task when compared to the control conditions. Our findings suggest that the updating of peripersonal space and body representations is not disrupted by induced pain. That is, experiencing acute pain does not give rise to distorted representations of the body and peripersonal space that can be present in people with chronic pain conditions.
Abstract.
Author URL.
Arthur T, Vine S, Brosnan M, Buckingham G (2019). Exploring how material cues drive sensorimotor prediction across different levels of autistic-like traits.
Exp Brain Res,
237(9), 2255-2267.
Abstract:
Exploring how material cues drive sensorimotor prediction across different levels of autistic-like traits.
Recent research proposes that sensorimotor difficulties, such as those experienced by many autistic people, may arise from atypicalities in prediction. Accordingly, we examined the relationship between non-clinical autistic-like traits and sensorimotor prediction in the material-weight illusion, where prior expectations derived from material cues typically bias one's perception and action. Specifically, prediction-related tendencies in perception of weight, gaze patterns, and lifting actions were probed using a combination of self-report, eye-tracking, motion-capture, and force-based measures. No prediction-related associations between autistic-like traits and sensorimotor control emerged for any of these variables. Follow-up analyses, however, revealed that greater autistic-like traits were correlated with reduced adaptation of gaze with changes in environmental uncertainty. These findings challenge proposals of gross predictive atypicalities in autistic people, but suggest that the dynamic integration of prior information and environmental statistics may be related to autistic-like traits. Further research into this relationship is warranted in autistic populations, to assist the development of future movement-based coaching methods.
Abstract.
Author URL.
Buckingham G, Allen K, Vine SJ, Harris DJ, Wood G, Tsaneva-Atanasova K, Wilson MR (2019). Investigating How Prior Knowledge Influences Perception and Action in Developmental Coordination Disorder.
Author URL.
Buckingham G, Donald H (2019). Move on up: Fingertip forces and felt heaviness are modulated by the goal of the lift.
Atten Percept Psychophys,
81(7), 2384-2390.
Abstract:
Move on up: Fingertip forces and felt heaviness are modulated by the goal of the lift.
When we interact with objects, we usually do so for a purpose. It is well known that the specific goal of an action can have a substantial effect on initial reach kinematics. No research, however, has examined the effect that the goal of a lift can have on the fingertip forces and perception of object weight when picking up an object to move it. Here, we report a study in which participants were asked to move objects laterally to a higher platform, to a lower platform, or to a platform of the same height. The objects were rated, on average, as feeling heavier after they were moved to a higher platform than after they were moved to a lower platform or to a platform of the same height. Furthermore, participants gripped and lifted with more force, and used higher rates of force, when moving objects to a higher platform compared with moving it to a platform of the same height. These findings suggest that the goal of movement in the context of object interaction may affect how heavy an object feels and the way in which it is lifted.
Abstract.
Author URL.
Harris DJ, Wilson MR, Buckingham G, Vine SJ (2019). No effect of transcranial direct current stimulation of frontal, motor or visual cortex on performance of a self-paced visuomotor skill.
Psychology of Sport and Exercise,
43, 368-373.
Abstract:
No effect of transcranial direct current stimulation of frontal, motor or visual cortex on performance of a self-paced visuomotor skill
Objectives: Transcranial direct current stimulation (tDCS) is a form of neurostimulation that can modulate neural activity in targeted brain regions through electrical current applied directly to the scalp. Previous findings have shown cognitive enhancement and improved motor learning following tDCS. Consequently, there has been growing interest in direct brain stimulation for enhancing sporting skills. We aimed to assess the effect of tDCS on golf putting performance and control of visual attention. Design: Using a mixed factorial design, the effect of stimulation (between-participants) was assessed at baseline, following stimulation and in a pressure test (within-participants). Methods: 73 novice golfers were randomly assigned to transcranial direct current stimulation of frontal, motor or visual cortex, or sham stimulation. Participants first performed a series of golf putts at baseline, then while receiving tDCS and finally under pressurised conditions. Putting performance (distance from the hole) and control of visual attention (quiet eye duration) was assessed. Results: There was no effect of real tDCS stimulation compared to sham stimulation on either performance or visual attention (quiet eye durations), for any stimulation site. Conclusions: While beneficial effects of tDCS have been found in computerised cognitive tests and simple motor tasks, there is currently little evidence that this will transfer to real-world sporting performance.
Abstract.
Chouinard PA, Matheson KG, Royals KA, Landry O, Buckingham G, Saccone EJ, Hocking DR (2019). The development of the size-weight illusion in children coincides with the development of nonverbal cognition rather than motor skills.
J Exp Child Psychol,
184, 48-64.
Abstract:
The development of the size-weight illusion in children coincides with the development of nonverbal cognition rather than motor skills.
We examined how the strength of the size-weight illusion develops with age in typically developing children. To this end, we recruited children aged 5-12 years and quantified the degree to which they experienced the illusion. We hypothesized that the strength of the illusion would increase with age. The results supported this hypothesis. We also measured abilities in manual dexterity, receptive language, and abstract reasoning to determine whether changes in illusion strength were associated with these factors. Manual dexterity and receptive language did not correlate with illusion strength. Conversely, illusion strength and abstract reasoning were tightly coupled with each other. Multiple regression further revealed that age, manual dexterity, and receptive language did not contribute more to the variance in illusion strength beyond children's abilities in abstract reasoning. Taken together, the effects of age on the size-weight illusion appear to be explained by the development of nonverbal cognition. These findings not only inform the literature on child development but also have implications for theoretical explanations on the size-weight illusion. We suggest that the illusion has a strong acquired component to it and that it is strengthened by children's reasoning skills and perhaps an understanding of the world that develops with age.
Abstract.
Author URL.
Paulun VC, Buckingham G, Goodale MA, Fleming RW (2019). The material-weight illusion disappears or inverts in objects made of two materials.
J Neurophysiol,
121(3), 996-1010.
Abstract:
The material-weight illusion disappears or inverts in objects made of two materials.
The material-weight illusion (MWI) occurs when an object that looks heavy (e.g. stone) and one that looks light (e.g. Styrofoam) have the same mass. When such stimuli are lifted, the heavier-looking object feels lighter than the lighter-looking object, presumably because well-learned priors about the density of different materials are violated. We examined whether a similar illusion occurs when a certain weight distribution is expected (such as the metal end of a hammer being heavier), but weight is uniformly distributed. In experiment 1, participants lifted bipartite objects that appeared to be made of two materials (combinations of stone, Styrofoam, and wood) but were manipulated to have a uniform weight distribution. Most participants experienced an inverted MWI (i.e. the heavier-looking side felt heavier), suggesting an integration of incoming sensory information with density priors. However, a replication of the classic MWI was found when the objects appeared to be uniformly made of just one of the materials ( experiment 2). Both illusions seemed to be independent of the forces used when the objects were lifted. When lifting bipartite objects but asked to judge the weight of the whole object, participants experienced no illusion ( experiment 3). In experiment 4, we investigated weight perception in objects with a nonuniform weight distribution and again found evidence for an integration of prior and sensory information. Taken together, our seemingly contradictory results challenge most theories about the MWI. However, Bayesian integration of competing density priors with the likelihood of incoming sensory information may explain the opposing illusions. NEW & NOTEWORTHY We report a novel weight illusion that contradicts all current explanations of the material-weight illusion: When lifting an object composed of two materials, the heavier-looking side feels heavier, even when the true weight distribution is uniform. The opposite (classic) illusion is found when the same materials are lifted in two separate objects. Identifying the common mechanism underlying both illusions will have implications for perception more generally. A potential candidate is Bayesian inference with competing priors.
Abstract.
Author URL.
Schneider TR, Buckingham G, Hermsdörfer J (2019). Torque-planning errors affect the perception of object properties and sensorimotor memories during object manipulation in uncertain grasp situations.
J Neurophysiol,
121(4), 1289-1299.
Abstract:
Torque-planning errors affect the perception of object properties and sensorimotor memories during object manipulation in uncertain grasp situations.
Predicting instead of only reacting to the properties of objects we grasp is crucial to dexterous object manipulation. Although we normally plan our grasps according to well-learned associations, we rely on implicit sensorimotor memories when we learn to interact with novel or ambiguous objects. However, little is known about the influence of sensorimotor predictions on subsequent perception and action. Here, young and elderly subjects repeatedly lifted an object in which the center of mass (CoM) was randomly varied between trials straight upward with the aim of preventing object tilts. After each lift, subjects indicated the location of the perceived CoM and reported how heavy the object felt. Surprisingly, we found that sensorimotor torque memories eventually causing initial lifting errors had substantial effects on the perception of torques, weight, and the torque planning for the next lift. Whereas subjects tended to partly retain their previous erroneous sensorimotor memories (instead of solely relying on the previously encountered torque for the upcoming motor plan), they perceived encountered torques to be stronger when they erroneously predicted them. Additionally, we found that torque prediction errors, as well as the actual torques, made the object feel heavier. By contrast, perception did not influence upcoming motor control. There were no major differences observed between the age groups. The sensorimotor impact on torque perception can be explained by internal feedforward prediction highlighting task-relevant errors, while the partial retention and adaptation of sensorimotor torque memories is reconciled with the trial-to-trial learning rule for motor adaptation. NEW & NOTEWORTHY the current study is the first to demonstrate in an object manipulation task in uncertainty that errors in the sensorimotor prediction of torques influence the perception of both torques and weight, whereas sensorimotor torque memories are partly retained and partly adapted to planning errors. Our results provide novel insights into the predictive mechanisms underpinning the common everyday task of object manipulation and further support theories about the predictive modulation of perception established in other neuroscientific disciplines.
Abstract.
Author URL.
Buckingham G, Parr J, Wood G, Day S, Chadwell A, Head J, Galpin A, Kenney L, Kyberd P, Gowen E, et al (2019). Upper- and lower-limb amputees show reduced levels of eeriness for images of prosthetic hands.
Psychon Bull Rev,
26(4), 1295-1302.
Abstract:
Upper- and lower-limb amputees show reduced levels of eeriness for images of prosthetic hands.
The "uncanny phenomenon" describes the feeling of unease associated with seeing an image that is close to appearing human. Prosthetic hands in particular are well known to induce this effect. Little is known, however, about this phenomenon from the viewpoint of prosthesis users. We studied perceptions of eeriness and human-likeness for images of different types of mechanical, cosmetic, and anatomic hands in upper-limb prosthesis users (n=9), lower-limb prosthesis users (n=10), prosthetists (n=16), control participants with no prosthetic training (n=20), and control participants who were trained to use a myoelectric prosthetic hand simulator (n=23). Both the upper- and lower-limb prosthesis user groups showed a reduced uncanny phenomenon (i.e. significantly lower levels of eeriness) for cosmetic prosthetic hands compared to the other groups, with no concomitant reduction in how these stimuli were rated in terms of human-likeness. However, a similar effect was found neither for prosthetists with prolonged visual experience of prosthetic hands nor for the group with short-term training with the simulator. These findings in the prosthesis users therefore seem likely to be related to limb absence or prolonged experience with prostheses.
Abstract.
Author URL.
Harris DJ, Buckingham G, Wilson MR, Vine SJ (2019). Virtually the same? How impaired sensory information in virtual reality may disrupt vision for action.
Exp Brain Res,
237(11), 2761-2766.
Abstract:
Virtually the same? How impaired sensory information in virtual reality may disrupt vision for action.
Virtual reality (VR) is a promising tool for expanding the possibilities of psychological experimentation and implementing immersive training applications. Despite a recent surge in interest, there remains an inadequate understanding of how VR impacts basic cognitive processes. Due to the artificial presentation of egocentric distance cues in virtual environments, a number of cues to depth in the optic array are impaired or placed in conflict with each other. Moreover, realistic haptic information is all but absent from current VR systems. The resulting conflicts could impact not only the execution of motor skills in VR but also raise deeper concerns about basic visual processing, and the extent to which virtual objects elicit neural and behavioural responses representative of real objects. In this brief review, we outline how the novel perceptual environment of VR may affect vision for action, by shifting users away from a dorsal mode of control. Fewer binocular cues to depth, conflicting depth information and limited haptic feedback may all impair the specialised, efficient, online control of action characteristic of the dorsal stream. A shift from dorsal to ventral control of action may create a fundamental disparity between virtual and real-world skills that has important consequences for how we understand perception and action in the virtual world.
Abstract.
Author URL.
2018
Harris DJ, Vine SJ, Wilson MR, McGrath JS, LeBel M-E, Buckingham G (2018). A randomised trial of observational learning from 2D and 3D models in robotically assisted surgery.
Surg Endosc,
32(11), 4527-4532.
Abstract:
A randomised trial of observational learning from 2D and 3D models in robotically assisted surgery.
BACKGROUND: Advances in 3D technology mean that both robotic surgical devices and surgical simulators can now incorporate stereoscopic viewing capabilities. While depth information may benefit robotic surgical performance, it is unclear whether 3D viewing also aids skill acquisition when learning from observing others. As observational learning plays a major role in surgical skills training, this study aimed to evaluate whether 3D viewing provides learning benefits in a robotically assisted surgical task. METHODS: 90 medical students were assigned to either (1) 2D or (2) 3D observation of a consultant surgeon performing a training task on the daVinci S robotic system, or (3) a no observation control, in a randomised parallel design. Subsequent performance and instrument movement metrics were assessed immediately following observation and at one-week retention. RESULTS: Both 2D and 3D groups outperformed no observation controls following the observation intervention (ps
Abstract.
Author URL.
Harris DJ, Vine SJ, Wilson MR, McGrath JS, LeBel ME, Buckingham G (2018). Action observation for sensorimotor learning in surgery.
British Journal of Surgery,
105(13), 1713-1720.
Abstract:
Action observation for sensorimotor learning in surgery
Background: Acquiring new motor skills to learn complex movements and master the use of a diverse range of instruments is fundamental for developing expertise in surgery. Although aspects of skill development occur through trial and error, watching the performance of another individual (action observation) is an increasingly important adjunct for the acquisition of these complex skills before performing a procedure. The aim of this review was to examine the evidence in support of the use of action observation in surgery. Methods: a narrative review of observational learning for surgical motor skills was undertaken. Searches of PubMed and PsycINFO databases were performed using the terms ‘observational learning’ OR ‘action observation’ AND ‘motor learning’ OR ‘skill learning’. Results: Factors such as the structure of physical practice, the skill level of the demonstrator and the use of feedback were all found to be important moderators of the effectiveness of observational learning. In particular, observation of both expert and novice performance, cueing attention to key features of the task, and watching the eye movements of expert surgeons were all found to enhance the effectiveness of observation. It was unclear, however, whether repeated observations were beneficial for skill learning. The evidence suggests that these methods can be employed to enhance surgical training curricula. Conclusion: Observational learning is an effective method for learning surgical skills. An improved understanding of observational learning may further inform the refinement and use of these methods in contemporary surgical training curricula.
Abstract.
Dimitriou P, Buckingham G (2018). Bimanual Lifting: Do Fingertip Forces Work Independently or Interactively?.
Journal of Motor Behavior,
50(1), 26-36.
Abstract:
Bimanual Lifting: Do Fingertip Forces Work Independently or Interactively?
Bimanual coordination is a commonplace activity, but the consequences of using both hands simultaneously are not well understood. The authors examined fingertip forces across 4 experiments in which participants undertook a range of bimanual tasks. They first measured fingertip forces during simultaneous lifts of 2 identical objects, noting that individuals held the objects with more force bimanually than unimanually. They then varied the mass of the objects held by each hand, noting that when both hands lifted together performance was equivalent to unimanual lifts. The authors next measured one hand's static grip force while the other hand lifted an object. They found a gradual reduction of grip force throughout the trial, but once again no evidence of one hand influencing the other. In the final experiment the authors tested whether tapping with one hand could influence the static grip force of its counterpart. Although the authors found no changes in static grip force as a direct consequence of the other hand's actions, they found clear differences from one task to the other, suggesting an effect of task instruction. Overall, these results suggest that fingertip forces are largely independent between hands in a bimanual lifting context, but are sensitive to different task requirements.
Abstract.
Buckingham G, Reid D, Potter LM (2018). How prior expectations influence older adults' perception and action during object interaction.
Multisensory Research,
31(3-4), 301-316.
Abstract:
How prior expectations influence older adults' perception and action during object interaction
The apparent size of an object can influence how we interact with and perceive the weight of objects in our environment. Little is known, however, about how this cue affects behaviour across the lifespan. Here, in the context of the size-weight illusion, we examined how visual size cues influenced the predictive application of fingertip forces and perceptions of heaviness in a group of older participants. We found that our older sample experienced a robust size-weight illusion, which did not differ from that experienced by younger participants. Older and young participants also experienced a real weight difference to a similar degree. By contrast, compared to younger participants our older group showed no evidence that size cues influenced the way they initially gripped and lifted the objects. These results highlight a unique dissociation between how perception and action diverge across the lifespan, and suggest that deficits in the ability to use prediction to guide actions might underpin some of the manual interaction difficulties experienced by the older adults.
Abstract.
LeBel M-E, Haverstock J, Cristancho S, van Eimeren L, Buckingham G (2018). Observational Learning During Simulation-Based Training in Arthroscopy: is it Useful to Novices?.
J Surg Educ,
75(1), 222-230.
Abstract:
Observational Learning During Simulation-Based Training in Arthroscopy: is it Useful to Novices?
OBJECTIVE: Observing experts constitutes an important and common learning experience for surgical residents before operating under direct guidance. However, studies suggest that exclusively observing experts may induce suboptimal motor learning, and watching errors from non-experts performing simple motor tasks may generate better performance. We investigated whether observational learning is transferrable to arthroscopy learning using virtual reality (VR) simulation. SETTING/DESIGN: in our surgical simulation laboratory, we compared students learning basic skills on a VR arthroscopy simulator after watching an expert video demonstration of VR arthroscopy tasks or a non-expert video demonstration of the same tasks to a Control group without video demonstration. Ninety students in 3 observing groups (expert, non-expert, and Control) subsequently completed the same procedure on a VR arthroscopy simulator. We hypothesized the non-expert-watching group would outperform the expert-watching group, and both groups to outperform the Control group. We examined performance pretest, posttest, and 1 week later. PARTICIPANTS: Participants were recruited from the final year of medical school and the very early first year of surgical residency training programs (orthopaedic surgery, urology, plastic surgery, and general surgery) at Western University (Ontario, Canada). RESULTS: all participants improved their overall performance from pretest to retention (p < 0.001). At initial retention testing, non-expert-watching group outperformed the other groups in camera path length p < 0.05 and time to completion, p < 0.05, and both the expert/non-expert groups surpassed the Control group in camera path length (p < 0.05). CONCLUSION: We suggest that error-observation may contribute to skills improvement in the non-expert-watching group. Allowing novices to observe techniques/errors of other novices may assist internalization of specific movements/skills required for effective motor performances. This study highlights the potential effect of observational learning on surgical skills acquisition and offers preliminary evidence for peer-based practice (combined non-experts and experts) as a complementary surgical motor skills training strategy.
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Author URL.
Buckingham G, Holler D, Michelakakis EE, Snow JC (2018). Preserved Object Weight Processing after Bilateral Lateral Occipital Complex Lesions.
J Cogn Neurosci,
30(11), 1683-1690.
Abstract:
Preserved Object Weight Processing after Bilateral Lateral Occipital Complex Lesions.
Object interaction requires knowledge of the weight of an object, as well as its shape. The lateral occipital complex (LOC), an area within the ventral visual pathway, is well known to be critically involved in processing visual shape information. Recently, however, LOC has also been implicated in coding object weight before grasping-a result that is surprising because weight is a nonvisual object property that is more relevant for motor interaction than visual perception. Here, we examined the causal role of LOC in perceiving heaviness and in determining appropriate fingertip forces during object lifting. We studied perceptions of heaviness and lifting behavior in a neuropsychological patient (M.C.) who has large bilateral occipitotemporal lesions that include LOC. We compared the patient's performance to a group of 18 neurologically healthy age-matched controls. Participants were asked to lift and report the perceived heaviness of a set of equally weighted spherical objects of various sizes-stimuli which typically induce the size-weight illusion, in which the smaller objects feel heavier than the larger objects despite having identical mass. Despite her ventral stream lesions, M.C. experienced a robust size-weight illusion induced by visual cues to object volume, and the magnitude of the illusion in M.C. was comparable to age-matched controls. Similarly, M.C. evinced predictive fingertip force scaling to visual size cues during her initial lifts of the objects that were well within the normal range. These single-case neuropsychological findings suggest that LOC is unlikely to play a causal role in computing object weight.
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Author URL.
Buckingham G, Parr J, Wood G, Vine S, Dimitriou P, Day S (2018). The impact of using an upper-limb prosthesis on the perception of real and illusory weight differences.
Psychon Bull Rev,
25(4), 1507-1516.
Abstract:
The impact of using an upper-limb prosthesis on the perception of real and illusory weight differences.
Little is known about how human perception is affected using an upper-limb prosthesis. To shed light on this topic, we investigated how using an upper-limb prosthesis affects individuals' experience of object weight. First, we examined how a group of upper-limb amputee prosthetic users experienced real mass differences and illusory weight differences in the context of the 'size-weight' illusion. Surprisingly, the upper-limb prosthetic users reported a markedly smaller illusion than controls, despite equivalent perceptions of a real mass difference. Next, we replicated this dissociation between real and illusory weight perception in a group of nonamputees who lifted the stimuli with an upper-limb myoelectric prosthetic simulator, again noting that the prosthetic users experienced illusory, but not real, weight differences as being weaker than controls. These findings not only validate the use of a prosthetic simulator as an effective tool for investigating perception and action but also highlight a surprising dissociation between the perception of real and illusory weight differences.
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Author URL.
2017
Cashaback JGA, McGregor HR, Pun HCH, Buckingham G, Gribble PL (2017). Does the sensorimotor system minimize prediction error or select the most likely prediction during object lifting?.
Journal of Neurophysiology,
117(1), 260-274.
Abstract:
Does the sensorimotor system minimize prediction error or select the most likely prediction during object lifting?
© 2017 the American Physiological Society. The human sensorimotor system is routinely capable of making accurate predictions about an object’s weight, which allows for energetically efficient lifts and prevents objects from being dropped. Often, however, poor predictions arise when the weight of an object can vary and sensory cues about object weight are sparse (e.g. picking up an opaque water bottle). The question arises, what strategies does the sensorimotor system use to make weight predictions when one is dealing with an object whose weight may vary? for example, does the sensorimotor system use a strategy that minimizes prediction error (minimal squared error) or one that selects the weight that is most likely to be correct (maximum a posteriori)? in this study we dissociated the predictions of these two strategies by having participants lift an object whose weight varied according to a skewed probability distribution. We found, using a small range of weight uncertainty, that four indexes of sensorimotor prediction (grip force rate, grip force, load force rate, and load force) were consistent with a feedforward strategy that minimizes the square of prediction errors. These findings match research in the visuomotor system, suggesting parallels in underlying processes. We interpret our findings within a Bayesian framework and discuss the potential benefits of using a minimal squared error strategy. NEW & NOTEWORTHY Using a novel experimental model of object lifting, we tested whether the sensorimotor system models the weight of objects by minimizing lifting errors or by selecting the statistically most likely weight. We found that the sensorimotor system minimizes the square of prediction errors for object lifting. This parallels the results of studies that investigated visually guided reaching, suggesting an overlap in the underlying mechanisms between tasks that involve different sensory systems.
Abstract.
Luebbers PE, Buckingham G, Butler MS (2017). The National Football League-225 Bench Press Test and the Size-Weight Illusion.
Percept Mot Skills,
124(3), 634-648.
Abstract:
The National Football League-225 Bench Press Test and the Size-Weight Illusion.
The purpose of this study was to test reports that size and arrangement manipulations of weight plates (i.e. inducing a size-weight illusion [SWI]) effect athletic weightlifting performance. The participants were 72 experienced, weight-trained collegiate American football players. Across three weeks, each athlete performed three different repetitions-to-fatigue bench press tests (NFL-225, SWI-225, and SWI-215). A multiple regression revealed a positive association between participants' strength relative to the test load and repetitions for NFL-225 and SWI-215, but no association with SWI-225. To explore these results, players were ranked into quartiles based on their one-repetition maximum relative to 102.27 kg (225 lb), and a 3 × 4 repeated measures analysis of variance was conducted. The primary finding was a significant Test Condition × Quartile interaction ( p = .004). Bonferroni-corrected pairwise comparisons revealed that Quartile 4 (those with lowest strength relative to test load) completed more repetitions for SWI-225 compared with NFL-225 ( p = .049). These results suggest that alternate weight plate arrangements may be beneficial for those whose bench press load is near the lifter's one-repetition maximum. However, variations of the SWI do not appear to affect the performance of repetitions-to-fatigue bench press tests for the majority of collegiate American football players.
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Author URL.
Harris DJ, Vine SJ, Wilson MR, McGrath JS, LeBel M-E, Buckingham G (2017). The effect of observing novice and expert performance on acquisition of surgical skills on a robotic platform.
PLoS One,
12(11).
Abstract:
The effect of observing novice and expert performance on acquisition of surgical skills on a robotic platform.
BACKGROUND: Observational learning plays an important role in surgical skills training, following the traditional model of learning from expertise. Recent findings have, however, highlighted the benefit of observing not only expert performance but also error-strewn performance. The aim of this study was to determine which model (novice vs. expert) would lead to the greatest benefits when learning robotically assisted surgical skills. METHODS: 120 medical students with no prior experience of robotically-assisted surgery completed a ring-carrying training task on three occasions; baseline, post-intervention and at one-week follow-up. The observation intervention consisted of a video model performing the ring-carrying task, with participants randomly assigned to view an expert model, a novice model, a mixed expert/novice model or no observation (control group). Participants were assessed for task performance and surgical instrument control. RESULTS: There were significant group differences post-intervention, with expert and novice observation groups outperforming the control group, but there were no clear group differences at a retention test one week later. There was no difference in performance between the expert-observing and error-observing groups. CONCLUSIONS: Similar benefits were found when observing the traditional expert model or the error-strewn model, suggesting that viewing poor performance may be as beneficial as viewing expertise in the early acquisition of robotic surgical skills. Further work is required to understand, then inform, the optimal curriculum design when utilising observational learning in surgical training.
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Author URL.
2016
Monaco S, Buckingham G, Sperandio I, Doug Crawford J (2016). Editorial: Perceiving and acting in the real world: from neural activity to behavior. Frontiers in Human Neuroscience, 10(APR2016), 1-4.
Buckingham G, Goodale MA, White JA, Westwood DA (2016). Equal-magnitude size-weight illusions experienced within and between object categories.
J Vis,
16(3).
Abstract:
Equal-magnitude size-weight illusions experienced within and between object categories.
In the size-weight illusion (SWI), small objects feel heavier than larger objects of the same mass. This effect is typically thought to be a consequence of the lifter's expectation that the large object will outweigh the small object, because objects of the same type typically get heavier as they get larger. Here, we show that this perceptual effect can occur across object category, where there are no strong expectations about the correspondence between size and mass. One group of participants lifted same-colored large and small cubes with the same mass as one another, while another group lifted differently-colored large and small cubes with the same mass as one another. The group who lifted the same-colored cubes experienced a robust SWI and initially lifted the large object with more force than the small object. By contrast, the group who lifted the different-colored objects did so with equal initial forces on the first trial, but experienced just as strong an illusion as those who lifted the same-colored objects. These results demonstrate that color cues can selectively influence the application of fingertip force rates while not impacting at all upon the lifter's perception of object weight, highlighting a stark dissociation in how prior information affects perception and action.
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Author URL.
Buckingham G, Michelakakis EE, Cole J (2016). Perceiving and acting upon weight illusions in the absence of somatosensory information.
J Neurophysiol,
115(4), 1946-1953.
Abstract:
Perceiving and acting upon weight illusions in the absence of somatosensory information.
When lifting novel objects, individuals' fingertip forces are influenced by a variety of cues such as volume and apparent material. This means that heavy-looking objects tend to be lifted with more force than lighter-looking objects, even when they weigh the same amount as one another. Expectations about object weight based on visual appearance also influence how heavy an object feels when it is lifted. For instance, in the "size-weight illusion," small objects feel heavier than equally weighted large objects. Similarly, in the "material-weight illusion," objects that seem to be made from light-looking materials feel heavier than objects of the same weight that appear to be made from heavy-looking materials. In this study, we investigated these perceptual and sensorimotor effects in IW, an individual with peripheral deafferentation (i.e. a loss of tactile and proprioception feedback). We examined his perceptions of heaviness and fingertip force application over repeated lifts of objects that varied in size or material properties. Despite being able to report real weight differences, IW did not appear to experience the size- or material-weight illusions. Furthermore, he showed no evidence of sensorimotor prediction based on size and material cues. The results are discussed in the context of forward models and their possible influence on weight perception and fingertip force control.
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Author URL.
Whitwell RL, Buckingham G, Enns JT, Chouinard PA, Goodale MA (2016). Rapid decrement in the effects of the Ponzo display dissociates action and perception.
Psychonomic Bulletin and Review,
23(4), 1157-1163.
Abstract:
Rapid decrement in the effects of the Ponzo display dissociates action and perception
It has been demonstrated that pictorial illusions have a smaller influence on grasping than they do on perceptual judgments. Yet to date this work has not considered the reduced influence of an illusion as it is measured repeatedly. Here we studied this decrement in the context of a Ponzo illusion to further characterize the dissociation between vision for perception and for action. Participants first manually estimated the lengths of single targets in a Ponzo display with their thumb and index finger, then actually grasped these targets in another series of trials, and then manually estimated the target lengths again in a final set of trials. The results showed that although the perceptual estimates and grasp apertures were equally sensitive to real differences in target length on the initial trials, only the perceptual estimates remained biased by the illusion over repeated measurements. In contrast, the illusion’s effect on the grasps decreased rapidly, vanishing entirely after only a few trials. Interestingly, a closer examination of the grasp data revealed that this initial effect was driven largely by undersizing the grip aperture for the display configuration in which the target was positioned between the diverging background lines (i.e. when the targets appeared to be shorter than they really were). This asymmetry between grasping apparently shorter and longer targets suggests that the sensorimotor system may initially treat the edges of the configuration as obstacles to be avoided. This finding highlights the sensorimotor system’s ability to rapidly update motor programs through error feedback, manifesting as an immunity to the effects of illusion displays even after only a few trials.
Abstract.
Buckingham G, Michelakakis EE, Rajendran G (2016). The Influence of Prior Knowledge on Perception and Action: Relationships to Autistic Traits. Journal of Autism and Developmental Disorders, 46(5), 1716-1724.
Buckingham G, MacDonald A (2016). The weight of expectation: Implicit, rather than explicit, prior expectations drive the size–weight illusion.
Quarterly Journal of Experimental Psychology,
69(9), 1831-1841.
Abstract:
The weight of expectation: Implicit, rather than explicit, prior expectations drive the size–weight illusion
In the size–weight illusion, small objects feel heavier than identically weighted larger objects. This illusion is thought to be a consequence of how one's prior expectations can influence conscious perception—lifters expect the large object to outweigh the small object and subsequently experience it as feeling lighter than they expected it to be. Here, we directly examined how a familiar object's identity can affect how heavy someone expects it to be, and how these expectations will influence subsequent perceptions of heaviness. We describe two novel weight illusions induced with familiar objects. In one condition, participants judged the weight of a set of similar-size objects with very different natural weights (a polystyrene sphere, a tennis ball, and a cricket ball), which had all been adjusted to weigh the same amount as one another. In this condition, participants experienced a small, but reliable, weight illusion, with the lightest looking ball feeling heavier than the heaviest looking ball. In the other condition, participants judged the weights of a different set of balls, which were different sizes, but similar natural weights, to one another (a golf ball, a foam soccer ball, and an inflated beach ball). Again, participants experienced a perceptual illusion, but in the opposite direction. Surprisingly, participant's perceptions matched, rather than contrasted with, their explicit expectations such that, even though they expected the golf ball to outweigh the beach ball they perceived the golf ball as feeling heavier than the beach ball. The effect of object mass appeared to dominate the effect of conscious expectations, suggesting that contrasting expectations of heaviness are not necessary to experience weight illusions and that current models of this robust perceptual effect must be revised.
Abstract.
Hesse C, Miller L, Buckingham G (2016). Visual information about object size and object position are retained differently in the visual brain: Evidence from grasping studies.
Neuropsychologia,
91, 531-543.
Abstract:
Visual information about object size and object position are retained differently in the visual brain: Evidence from grasping studies.
Many experiments have examined how the visual information used for action control is represented in our brain, and whether or not visually-guided and memory-guided hand movements rely on dissociable visual representations that are processed in different brain areas (dorsal vs. ventral). However, little is known about how these representations decay over longer time periods and whether or not different visual properties are retained in a similar fashion. In three experiments we investigated how information about object size and object position affect grasping as visual memory demands increase. We found that position information decayed rapidly with increasing delays between viewing the object and initiating subsequent actions - impacting both the accuracy of the transport component (lower end-point accuracy) and the grasp component (larger grip apertures) of the movement. In contrast, grip apertures and fingertip forces remained well-adjusted to target size in conditions in which positional information was either irrelevant or provided, regardless of delay, indicating that object size is encoded in a more stable manner than object position. The findings provide evidence that different grasp-relevant properties are encoded differently by the visual system. Furthermore, we argue that caution is required when making inferences about object size representations based on alterations in the grip component as these variations are confounded with the accuracy with which object position is represented. Instead fingertip forces seem to provide a reliable and confound-free measure to assess internal size estimations in conditions of increased visual uncertainty.
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Author URL.
2015
Carey DP, Otto-de Haart EG, Buckingham G, Dijkerman HC, Hargreaves EL, Goodale MA (2015). Are there right hemisphere contributions to visually-guided movement? Manipulating left hand reaction time advantages in dextrals.
Front Psychol,
6Abstract:
Are there right hemisphere contributions to visually-guided movement? Manipulating left hand reaction time advantages in dextrals.
Many studies have argued for distinct but complementary contributions from each hemisphere in the control of movements to visual targets. Investigators have attempted to extend observations from patients with unilateral left- and right-hemisphere damage, to those using neurologically-intact participants, by assuming that each hand has privileged access to the contralateral hemisphere. Previous attempts to illustrate right hemispheric contributions to the control of aiming have focussed on increasing the spatial demands of an aiming task, to attenuate the typical right hand advantages, to try to enhance a left hand reaction time advantage in right-handed participants. These early attempts have not been successful. The present study circumnavigates some of the theoretical and methodological difficulties of some of the earlier experiments, by using three different tasks linked directly to specialized functions of the right hemisphere: bisecting, the gap effect, and visuospatial localization. None of these tasks were effective in reducing the magnitude of left hand reaction time advantages in right handers. Results are discussed in terms of alternatives to right hemispheric functional explanations of the effect, the one-dimensional nature of our target arrays, power and precision given the size of the left hand RT effect, and the utility of examining the proportions of participants who show these effects, rather than exclusive reliance on measures of central tendency and their associated null hypothesis significance tests.
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Author URL.
Paulun VC, Buckingham G, Gegenfurtner KR, Fleming RW, Goodale MA (2015). Inversion of the Material-Weight Illusion in objects made of two materials.
Author URL.
Buckingham G, Wong JD, Tang M, Gribble PL, Goodale MA (2015). Observing object lifting errors modulates cortico-spinal excitability and improves object lifting performance.
Cortex,
50, 115-124.
Abstract:
Observing object lifting errors modulates cortico-spinal excitability and improves object lifting performance
Observing the actions of others has been shown to modulate cortico-spinal excitability and affect behaviour. However, the sensorimotor consequences of observing errors are not well understood. Here, participants watched actors lift identically weighted large and small cubes which typically elicit expectation-based fingertip force errors. One group of participants observed the standard overestimation and underestimation-style errors that characterise early lifts with these cubes (Error video - EV). Another group watched the same actors performing the well-adapted error-free lifts that characterise later, well-practiced lifts with these cubes (No error video - NEV). We then examined actual object lifting performance in the subjects who watched the EV and NEV. Despite having similar cognitive expectations and perceptions of heaviness, the group that watched novice lifters making errors themselves made fewer overestimation-style errors than those who watched the expert lifts. To determine how the observation of errors alters cortico-spinal excitability, we measured motor evoked potentials in separate group of participants while they passively observed these EV and NEV. Here, we noted a novel size-based modulation of cortico-spinal excitability when observing the expert lifts, which was eradicated when watching errors. Together, these findings suggest that individuals' sensorimotor systems are sensitive to the subtle visual differences between observing novice and expert performance.
Abstract.
Buckingham G, Cole J (2015). Perceiving and acting upon weight illusions in the absence of somatosensory information.
Author URL.
Buckingham G, Milne JL, Byrne CM, Goodale MA (2015). The Size-Weight Illusion Induced Through Human Echolocation.
Psychological Science,
26(2), 237-242.
Abstract:
The Size-Weight Illusion Induced Through Human Echolocation
Certain blind individuals have learned to interpret the echoes of self-generated sounds to perceive the structure of objects in their environment. The current work examined how far the influence of this unique form of sensory substitution extends by testing whether echolocation-induced representations of object size could influence weight perception. A small group of echolocation experts made tongue clicks or finger snaps toward cubes of varying sizes and weights before lifting them. These echolocators experienced a robust size-weight illusion. This experiment provides the first demonstration of a sensory substitution technique whereby the substituted sense influences the conscious perception through an intact sense.
Abstract.
Buckingham G, Bieńkiewicz M, Rohrbach N, Hermsdörfer J (2015). The impact of unilateral brain damage on weight perception, sensorimotor anticipation, and fingertip force adaptation.
Vision Research,
115, 231-237.
Abstract:
The impact of unilateral brain damage on weight perception, sensorimotor anticipation, and fingertip force adaptation
Damage to the left parietal cortex can lead to apraxia - a selective deficit in tool use and action planning. There is conflicting evidence as to whether this disorder affects more fundamental motor parameters, such as applying the appropriate forces to lift objects based upon how heavy they look. Here we examined how individuals with left and right-lateralized brain damage lift and perceive the weight of objects of the same mass which vary in their size and material properties. No clear differences emerged between the groups in terms of how visual material properties affected their perceptions of object weight or their initial application of grip and load forces. There was, however, some evidence that unilateral brain injury impaired the use of size cues for the parameterization of grip forces.
Abstract.
Hesse C, Miller L, Buckingham G (2015). Visual memory in reaching and grasping.
Author URL.
2014
Buckingham G, Carey DP (2014). Attentional asymmetries - Cause or consequence of human right handedness?.
Frontiers in Psychology,
5(OCT).
Abstract:
Attentional asymmetries - Cause or consequence of human right handedness?
It is well established that the vast majority of the population favors their right hand when performing complex manual tasks. However, the developmental and evolutionary underpinnings of human manual asymmetries remain contentious. One often overlooked suggestion is that right handedness may stem from an asymmetrical bias in attention, with the right hand being allocated more attentional resources during bimanual tasks than the left hand (Peters, 1981). This review examines the evidence for attentional asymmetries during a variety of bimanual tasks, and critically evaluates the explanatory power of this hypothesis for explaining the depth and breadth of individual- and population-level manual asymmetries. We conclude that, while the attentional bias hypothesis is well-supported in adults, it requires further validation from a developmental perspective to explain the full breadth of adult manual laterality.
Abstract.
Buckingham G, Carey DP (2014). Attentional asymmetries - cause or consequence of human right handedness?.
Front Psychol,
5Abstract:
Attentional asymmetries - cause or consequence of human right handedness?
It is well established that the vast majority of the population favors their right hand when performing complex manual tasks. However, the developmental and evolutionary underpinnings of human manual asymmetries remain contentious. One often overlooked suggestion is that right handedness may stem from an asymmetrical bias in attention, with the right hand being allocated more attentional resources during bimanual tasks than the left hand (Peters, 1981). This review examines the evidence for attentional asymmetries during a variety of bimanual tasks, and critically evaluates the explanatory power of this hypothesis for explaining the depth and breadth of individual- and population-level manual asymmetries. We conclude that, while the attentional bias hypothesis is well-supported in adults, it requires further validation from a developmental perspective to explain the full breadth of adult manual laterality.
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Author URL.
Buckingham G (2014). Getting a grip on heaviness perception: a review of weight illusions and their probable causes.
Experimental Brain Research,
232(6), 1623-1629.
Abstract:
Getting a grip on heaviness perception: a review of weight illusions and their probable causes
Weight illusions-where one object feels heavier than an identically weighted counterpart-have been the focus of many recent scientific investigations. The most famous of these illusions is the 'size-weight illusion', where a small object feels heavier than an identically weighted, but otherwise similar-looking, larger object. There are, however, a variety of similar illusions which can be induced by varying other stimulus properties, such as surface material, temperature, colour, and even shape. Despite well over 100 years of research, there is little consensus about the mechanisms underpinning these illusions. In this review, I will first provide an overview of the weight illusions that have been described. I will then outline the dominant theories that have emerged over the past decade for why we consistently misperceive the weights of objects which vary in size, with a particular focus on the role of lifters' expectations of heaviness. Finally, I will discuss the magnitude of the various weight illusions and suggest how this largely overlooked facet of the topic might resolve some of the debates surrounding the cause of these misperceptions of heaviness. © 2014 Springer-Verlag.
Abstract.
Colino FL, Buckingham G, Cheng DT, van Donkelaar P, Binsted G (2014). Tactile gating in a reaching and grasping task.
Physiol Rep,
2(3).
Abstract:
Tactile gating in a reaching and grasping task.
Abstract a multitude of events bombard our sensory systems at every moment of our lives. Thus, it is important for the sensory cortex to gate unimportant events. Tactile suppression is a well-known phenomenon defined as a reduced ability to detect tactile events on the skin before and during movement. Previous experiments found detection rates decrease just prior to and during finger abduction, and decrease according to the proximity of the moving effector. This study examined how tactile detection changes during a reach to grasp. Fourteen human participants used their right hand to reach and grasp a cylinder. Tactors were attached to the index finger, the fifth digit, and the forearm of both the right and left arm and vibrated at various epochs relative to a "go" tone. Results showed that detection rates at the forearm decreased before movement onset; whereas at the right index finger, right fifth digit and at the left index finger, left fifth digit, and forearm sites did not decrease like in the right forearm. These results indicate that the task affects gating dynamics in a temporally- and contextually dependent manner and implies that feed-forward motor planning processes can modify sensory signals.
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Author URL.
Buckingham G, Byrne CM, Paciocco J, van Eimeren L, Goodale MA (2014). Weightlifting exercise and the size-weight illusion.
Attention, Perception, and Psychophysics,
76(2), 452-459.
Abstract:
Weightlifting exercise and the size-weight illusion
In the size-weight illusion (SWI), large objects feel lighter than equally weighted small objects. In the present study, we investigated whether this powerful weight illusion could influence real-lift behavior-namely, whether individuals would perform more bicep curls with a dumbbell that felt subjectively lighter than with an identically weighted, but heavier-feeling, dumbbell. Participants performed bicep curls until they were unable to continue with both a large, light-feeling 5-lb dumbbell and a smaller, heavy-feeling 5-lb dumbbell. No differences emerged in the amounts of exercise that participants performed with each dumbbell, even though they felt that the large dumbbell was lighter than the small dumbbell. Furthermore, in a second experiment, we found no differences in how subjectively tired participants felt after exercising for a set time with either dumbbell. We did find, however, differences in the lifting dynamics, such that the small dumbbell was moved at a higher average velocity and peak acceleration. These results suggest that the SWI does not appear to influence exercise outcomes, suggesting that perceptual illusions are unlikely to affect one's ability to persevere with lifting weights. © 2013 Psychonomic Society, Inc.
Abstract.
2013
Buckingham G, Haverstock J, van Eimeren L, Cristancho S, Faber K, Lebel M-E, Goodale MA (2013). Observing errors vs. expertise during surgical training.
Author URL.
Whitwell RL, Buckingham G (2013). Reframing the action and perception dissociation in DF: Haptics matters, but how?.
Journal of Neurophysiology,
109(3), 621-624.
Abstract:
Reframing the action and perception dissociation in DF: Haptics matters, but how?
Goodale and Milner's (1992) "vision-for-action" and "vision-for-perception" account of the division of labor between the dorsal and ventral "streams" has come to dominate contemporary views of the functional roles of these two pathways. Nevertheless, some lines of evidence for the model remain controversial. Recently, Thomas Schenk reexamined visual form agnosic patient DF's spared anticipatory grip scaling to object size, one of the principal empirical pillars of the model. Based on this new evidence, Schenk rejects the original interpretation of DF's spared ability that was based on segregated processing of object size and argues that DF's spared grip scaling relies on haptic feedback to calibrate visual egocentric cues that relate the posture of the hand to the visible edges of the goal-object. However, a careful consideration of the tasks that Schenk employed reveals some problems with his claim. We suspect that the core issues of this controversy will require a closer examination of the role that cognition plays in the operation of the dorsal and ventral streams in healthy controls and in patient DF. © 2013 the American Physiological Society.
Abstract.
Buckingham G, Goodale MA (2013). Size Matters: a Single Representation Underlies Our Perceptions of Heaviness in the Size-Weight Illusion.
PLoS ONE,
8(1).
Abstract:
Size Matters: a Single Representation Underlies Our Perceptions of Heaviness in the Size-Weight Illusion
In the size-weight illusion (SWI), a small object feels heavier than an equally-weighted larger object. It is thought that this illusion is a consequence of the way that we internally represent objects' properties - lifters expect one object to outweigh the other, and the subsequent illusion reflects a contrast with their expectations. Similar internal representations are also thought to guide the application of fingertip forces when we grip and lift objects. To determine the nature of the representations underpinning how we lift objects and perceive their weights, we examined weight judgments in addition to the dynamics and magnitudes of the fingertip forces when individuals lifted small and large exemplars of metal and polystyrene cubes, all of which had been adjusted to have exactly the same mass. Prior to starting the experiment, subjects expected the density of the metal cubes to be higher than that of the polystyrene cubes. Their illusions, however, did not reflect their conscious expectations of heaviness; instead subjects experienced a SWI of the same magnitude regardless of the cubes' material. Nevertheless, they did report that the polystyrene cubes felt heavier than the metal ones (i.e. they experienced a material-weight illusion). Subjects persisted in lifting the large metal cube with more force than the small metal cube, but lifted the large polystyrene cube with roughly the same amount of force that they used to lift the small polystyrene cube. These findings suggest that our perceptual and sensorimotor representations are not only functionally independent from one another, but that the perceptual system represents a more single, simple size-weight relationship which appears to drive the SWI itself. © 2013 Buckingham, Goodale.
Abstract.
Buckingham G, Goodale MA (2013). When the predictive brain gets it really wrong.
Behavioral and Brain Sciences,
36(3), 208-209.
Abstract:
When the predictive brain gets it really wrong
Clark examines the notion of the predictive brain as a unifying model for cognitive neuroscience, from the level of basic neural processes to sensorimotor control. Although we are in general agreement with this notion, we feel that there are many details that still need to be fleshed out from the standpoint of perception and action. © 2013 Cambridge University Press.
Abstract.
2012
Buckingham G, Ranger NS, Goodale MA (2012). Handedness, laterality and the size-weight illusion.
Cortex,
48(10), 1342-1350.
Abstract:
Handedness, laterality and the size-weight illusion.
The goal of this study was to determine how handedness and lifting hand influence the way in which we lift objects and perceive their weights. To this end, we examined the fingertip forces and perceptual judgements of 30 left-handers and 30 right-handers during lifts of specially constructed 'size-weight illusion' (SWI) cubes with their left and right hands. All participants completed a series of lifts first with one hand and then the other, so we could additionally examine asymmetries in the retention and transfer of force information between the limbs. Right-handers experienced a larger illusion with their left hand than they did with their right hand, whereas left-handers showed no such asymmetry in their illusions. The perceptual illusion's independence from the application of fingertip force was highlighted by an unexpected lack of asymmetry in terms of fingertip force scaling. Left- and right-handers showed no dominant hand advantage in this task - they were no more skilled at correcting their fingertip force errors with their preferred hand than they were with their non-preferred hand. In addition, although no asymmetries were observed with regard to the most efficient direction of intermanual transfer, the right-handed individuals transferred force information between the hands more effectively than the left-handers. Overall, these findings indicate that hand dominance does not affect the control of the fingertip forces, suggesting that existing models of cerebral laterality must be re-visited to consider kinetic (i.e. related to forces), as well as kinematic (i.e. related to movement) variables.
Abstract.
Author URL.
Buckingham G, Haverstock J, Lebel M-E, Christancho S, Faber K, Goodale MA (2012). The Observation of Errors During Surgical Training.
Author URL.
2011
Buckingham G, Main JC, Carey DP (2011). Asymmetries in motor attention during a cued bimanual reaching task: left and right handers compared.
Cortex,
47(4), 432-440.
Abstract:
Asymmetries in motor attention during a cued bimanual reaching task: left and right handers compared.
Several studies have indicated that right handers have attention biased toward their right hand during bimanual coordination (Buckingham and Carey, 2009; Peters, 1981). To determine if this behavioral asymmetry was linked to cerebral lateralization, we examined this bias in left and right handers by combining a discontinuous double-step reaching task with a Posner-style hand cueing paradigm. Left and right handed participants received a tactile cue (valid on 80% of trials) prior to a bimanual reach to target pairs. Right handers took longer to inhibit their right hand and made more right hand errors, suggesting that their dominant hand was more readily primed to move than their non-dominant hand, likely due to the aforementioned attentional bias. Left handers, however, showed neither of these asymmetries, suggesting that they lack an equivalent dominant hand attentional bias. The findings are discussed in relation to recent unimanual handedness tasks in right and left handers, and the lateralization of systems for speech, language and motor attention.
Abstract.
Author URL.
Buckingham G, Ranger NS, Goodale MA (2011). The material-weight illusion induced by expectations alone.
Atten Percept Psychophys,
73(1), 36-41.
Abstract:
The material-weight illusion induced by expectations alone.
In the material-weight illusion (MWI), equally weighted objects that appear to be made from different materials are incorrectly perceived as having different weights when they are lifted one after the other. Here, we show that continuous visual experience of the lift is not a prerequisite for this compelling misperception of weight; merely priming the lifters' expectations of heaviness is sufficient for them to experience a robust MWI. Furthermore, these expectations continued to influence the load force used to lift MWI-inducing stimuli trial after trial, supporting the notion that vision plays an important role in the skillful lifting of objects.
Abstract.
Author URL.
Buckingham G, Ranger NS, Goodale MA (2011). The role of vision in detecting and correcting fingertip force errors during object lifting.
Journal of Vision,
11(1), 1-14.
Abstract:
The role of vision in detecting and correcting fingertip force errors during object lifting
Vision provides many reliable cues about the likely weight of an object, allowing individuals to predict how heavy it will be. The forces used to lift an object for the first time reflect these predictions. This, however, leads to inevitable errors during lifts of objects that weigh unexpected amounts. Fortunately, these errors are rarely made twice in a row-lifters have the impressive ability to detect and correct large or small misapplications of fingertip forces, even while experiencing weight illusions. Although it has been assumed that we detect and correct these errors exclusively with our sense of touch, recent evidence has demonstrated a role for vision in this fingertip force scaling. Here, we demonstrate that even when stimulus set size, delay, and modality are controlled for, individuals are unable to skillfully scale their grip and load force rates over repeated lifts without vision. However, eliminating only the task-relevant visual information, while maintaining the rest of the visual world, shifts participants back into the normal, skilled mode of control. These findings clarify the role of visual information in the ostensibly haptic task of lifting objects, suggesting individuals use priors under conditions where uncertainty is high. © ARVO.
Abstract.
Buckingham G, Ranger NS, Goodale MA (2011). The role of vision in detecting and correcting fingertip force errors during object lifting.
Journal of vision,
11(1).
Abstract:
The role of vision in detecting and correcting fingertip force errors during object lifting.
Vision provides many reliable cues about the likely weight of an object, allowing individuals to predict how heavy it will be. The forces used to lift an object for the first time reflect these predictions. This, however, leads to inevitable errors during lifts of objects that weigh unexpected amounts. Fortunately, these errors are rarely made twice in a row-lifters have the impressive ability to detect and correct large or small misapplications of fingertip forces, even while experiencing weight illusions. Although it has been assumed that we detect and correct these errors exclusively with our sense of touch, recent evidence has demonstrated a role for vision in this fingertip force scaling. Here, we demonstrate that even when stimulus set size, delay, and modality are controlled for, individuals are unable to skillfully scale their grip and load force rates over repeated lifts without vision. However, eliminating only the task-relevant visual information, while maintaining the rest of the visual world, shifts participants back into the normal, skilled mode of control. These findings clarify the role of visual information in the ostensibly haptic task of lifting objects, suggesting individuals use priors under conditions where uncertainty is high.
Abstract.
2010
Buckingham G, Binsted G, Carey DP (2010). Bimanual reaching across the hemispace: which hand is yoked to which?.
Brain Cogn,
74(3), 341-346.
Abstract:
Bimanual reaching across the hemispace: which hand is yoked to which?
When both hands perform concurrent goal-directed reaches, they become yoked to one another. To investigate the direction of this coupling (i.e. which hand is yoked to which), the temporal dynamics of bimanual reaches were compared with equivalent-amplitude unimanual reaches. These reaches were to target pairs located on either the left or right sides of space; meaning that in the bimanual condition, one hand's contralateral (more difficult) reach accompanied by the other hand's ipsilateral (easier) reach. By comparing which hand's difficult reach was improved more by the presence of the other hand's easier ipsilateral reach, we were able to demonstrate asymmetries in the coupling. When the cost of bimanual reaching was controlled for the contralateral reaching left hand's performance was improved, suggesting that the left hand is yoked to the right during motor output. In contrast, the right hand showed the greatest improvements for contralateral reaching in terms of reaction time, pointing toward a dominant role for the left hand in the processes prior to movement onset. The results may point toward a mechanism for integrating the unitary system of attention with bimanual coordination.
Abstract.
Author URL.
Buckingham G, Carey DP, Colino FL, deGrosbois J, Binsted G (2010). Gating of vibrotactile detection during visually guided bimanual reaches.
Exp Brain Res,
201(3), 411-419.
Abstract:
Gating of vibrotactile detection during visually guided bimanual reaches.
It is far more difficult to detect a small tactile stimulation on a finger that is moving compared to when it is static. This suppression of tactile information during motion, known as tactile gating, has been examined in some detail during single-joint movements. However, the existence and time course of this gating has yet to be examined during visually guided multi-joint reaches, where sensory feedback may be paramount. The current study demonstrated that neurologically intact humans are unable to detect a small vibratory stimulus on one of their index fingers during a bimanual reach toward visual targets. By parametrically altering the delay between the visual target onset and the vibration, it was demonstrated that this gating was even apparent before participants started moving. A follow up experiment using electromyography indicated that gating was likely to occur even before muscle activity had taken place. This unique demonstration of tactile gating during a task reliant on visual feedback supports the notion this phenomenon is due to a central command, rather than a masking of sensory signals by afferent processing during movement.
Abstract.
Author URL.
Buckingham G, Goodale MA (2010). Lifting without seeing: the role of vision in perceiving and acting upon the size weight illusion.
PLoS One,
5(3).
Abstract:
Lifting without seeing: the role of vision in perceiving and acting upon the size weight illusion.
BACKGROUND: Our expectations of an object's heaviness not only drive our fingertip forces, but also our perception of heaviness. This effect is highlighted by the classic size-weight illusion (SWI), where different-sized objects of identical mass feel different weights. Here, we examined whether these expectations are sufficient to induce the SWI in a single wooden cube when lifted without visual feedback, by varying the size of the object seen prior to the lift. METHODOLOGY/PRINCIPAL FINDINGS: Participants, who believed that they were lifting the same object that they had just seen, reported that the weight of the single, standard-sized cube that they lifted on every trial varied as a function of the size of object they had just seen. Seeing the small object before the lift made the cube feel heavier than it did after seeing the large object. These expectations also affected the fingertip forces that were used to lift the object when vision was not permitted. The expectation-driven errors made in early trials were not corrected with repeated lifting, and participants failed to adapt their grip and load forces from the expected weight to the object's actual mass in the same way that they could when lifting with vision. CONCLUSIONS/SIGNIFICANCE: Vision appears to be crucial for the detection, and subsequent correction, of the ostensibly non-visual grip and load force errors that are a common feature of this type of object interaction. Expectations of heaviness are not only powerful enough to alter the perception of a single object's weight, but also continually drive the forces we use to lift the object when vision is unavailable.
Abstract.
Author URL.
Buckingham G, Goodale MA (2010). The influence of competing perceptual and motor priors in the context of the size-weight illusion.
Exp Brain Res,
205(2), 283-288.
Abstract:
The influence of competing perceptual and motor priors in the context of the size-weight illusion.
When lifting objects of identical mass but different sizes, people perceive the smaller objects as weighing more than the larger ones (the 'size-weight' illusion, SWI). While individual's grip and load force rates are rapidly scaled to the objects' actual mass, the magnitude of the force used to lift these SWI-inducing objects is rarely discussed. Here, we show that participants continue to apply a greater loading force to a large SWI-inducing cube than to a small SWI cube, lift after lift. These differences in load force persisted long after initial errors in grip and load force rates had been corrected. Interestingly, participants who showed the largest illusion made the smallest errors in load force. This unexpected relationship suggests that the motor system is consistently biased toward the expectations of heaviness for a particular stimulus in a Bayesian fashion, and that this loading error is subsequently reduced by SWI perceptual errors in the opposite direction.
Abstract.
Author URL.
2009
Buckingham G, Cant JS, Goodale MA (2009). Living in a material world: How visual cues to material properties affect the way that we lift objects and perceive their weight.
Journal of Neurophysiology,
102(6), 3111-3118.
Abstract:
Living in a material world: How visual cues to material properties affect the way that we lift objects and perceive their weight
The visual properties of an object provide many cues as to the tensile strength, compliance, and density of the material from which it is made. However, it is not well understood how these implicit associations affect our perceptions of these properties and how they determine the initial forces that are applied when an object is picked up. Here we examine the effects of these cues on such forces by using the classic "material-weight illusion" (MWI). Grip and load forces were measured in three experiments as participants lifted cubes made from metal, wood, and expanded polystyrene. These cubes were adjusted to have a different mass than would be expected for a particular material. For the initial lifts, the forces were scaled to the expected weight of each object, such that the metal block was gripped and lifted with more force than the polystyrene one. After a few lifts, however, participants scaled their forces to the actual weight of the blocks, implicitly disregarding the misleading visual cues to each block's composition (experiments 1 and 2). Despite this rapid rescaling, participants experienced a robust MWI throughout the duration of the experiments. In fact, the grip and load forces never matched the perception of weight until the differences in the visual surface properties between the blocks were removed (experiment 3). These findings are discussed in relation to recent debates about the underlying causes of weight-based illusions and the effect of top-down visual cues on perception and action. Copyright © 2009 the American Physiological Society.
Abstract.
Buckingham G, Carey DP (2009). Rightward biases during bimanual reaching.
Exp Brain Res,
194(2), 197-206.
Abstract:
Rightward biases during bimanual reaching.
Two experiments were carried out to investigate whether attention is biased toward the right hand of right handers during bimanual coordination (Peters 1981). A novel discontinuous double-step reaching task was developed, where right-handed participants executed a bimanual reach followed by a left or right hand unimanual reach. Asymmetries in the downtime between the bimanual and unimanual reach portions (the refractory period) were used to infer the direction of attention. A shorter right hand refractory period was found in the first experiment, indicating a rightward bias in attention. In a second experiment, shifting the focus of attention during the bimanual portion of the reach altered the direction and magnitude of the asymmetry in a way consistent with the attentional bias hypothesis. The role of attention during bimanual reaching, and a further programme of experimental work aimed at clarifying the nature of these rightward biases during discrete bimanual coordination is discussed.
Abstract.
Author URL.
2008
Buckingham G, Carey DP (2008). Attentional biases toward the dominant hand during bimanual reaching.
Author URL.
Buckingham G, Carey DP (2008). Investigating bimanual coordination in dominant and non-dominant virtual hands.
Laterality,
13(6), 514-526.
Abstract:
Investigating bimanual coordination in dominant and non-dominant virtual hands.
A bias in attention towards the dominant hand has been cited as a possible factor in the lateralisation of human bimanual coordination (Peters, 1981). A mirror was placed between the hands of 18 dextral participants performing rhythmic anti-phase movements. This set-up gave the appearance of a reflected virtual hand (moving in time with the un-occluded hand), in the same spatial location as the occluded left or right hand. This asymmetrical conflict between vision and action examined whether the left hand would show higher levels of error when replaced by a virtual right hand than the converse condition. Higher levels of error were observed during performance of the anti-phase pattern overall in the conditions where the mirror was present (compared to control conditions without the mirror). However, this effect did not differ between hands. The implications for the mirror paradigm, possible explanations for the lack of asymmetry, and the consequences for the attentional bias hypothesis are discussed.
Abstract.
Author URL.
Binsted G, Buckingham G, Heath M, Carey D (2008). Sensori-motor gating of tactile input during reaching.
Author URL.
2007
Buckingham G, Carey D (2007). Asymmetries in attention toward the dominant hand: Input or output?.
Author URL.
2006
Buckingham G, Carey DP, Sahraie A (2006). Reflections on bimanual phase shifting under different visual conditions.
Author URL.
Buckingham G, DeBruine LM, Little AC, Welling LLM, Conway CA, Tiddeman BP, Jones BC (2006). Visual adaptation to masculine and feminine faces influences generalized preferences and perceptions of trustworthiness.
Evolution and Human Behavior,
27(5), 381-389.
Abstract:
Visual adaptation to masculine and feminine faces influences generalized preferences and perceptions of trustworthiness
Although previous studies of individual differences in preferences for masculinity in male faces have typically emphasized the importance of factors such as changes in levels of sex hormones during the menstrual cycle, other research has demonstrated that recent visual experience with faces also influences preferences for sexual dimorphism in faces. Adaptation to either masculine or feminine faces increases preferences for novel faces that are similar to those that were recently seen. Here, we replicate this effect and demonstrate that adaptation to masculine or feminine faces also influences the extent to which masculine faces are perceived as trustworthy. These adaptation effects may reflect a proximate mechanism that contributes to the development of face preferences within individuals, underpins phenomena such as imprinting-like effects and condition-dependent face preferences, and shapes personality attributions to faces that play an important role in romantic partner and associate choices. Furthermore, our findings also support the proposal that visual exposure alone cannot explain the context specificity of attitudes to self-resemblance in faces. © 2006 Elsevier Inc. All rights reserved.
Abstract.
