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1.
Optom Vis Sci ; 98(7): 802-808, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34328458

RESUMO

SIGNIFICANCE: Experts in different sports show superior decision-making skills compared with novices, but little is known about its development in youth players. This study shows that the age-related improvements in visual cognition and accumulation of sport-specific experience explain a considerable amount of the development in decision making in volleyball. PURPOSE: The aim of this study was to investigate the mediating effects of visual cognition and volleyball experience on the relationship between age and decision making in youth volleyball players. METHODS: A total of 171 female volleyball players aged 6 to 17 years performed a sport-specific, video-based test of decision making, as well as four different visual cognition tests. Using structural equation modeling, we examined if volleyball experience and a latent variable constructed from the four tests of visual cognition act as parallel mediators in the association between age and decision making. RESULTS: The parallel multiple mediation model for the association between age and decision making was supported in youth volleyball players. Moreover, significant indirect effects and a nonsignificant direct effect indicated that visual cognition and experience fully mediated the relation between age and decision making and together explain 38% of the variance in decision-making performance. The effects of both mediators were not significantly different, and there was no residual correlation between experience and visual cognition, which indicates that these mediators are unrelated to each other. CONCLUSIONS: Our findings demonstrate that visual cognition and volleyball experience mediate the relation between age and decision making independently, which indicates that they each influence different parts of the decision-making process. These results highlight the importance of the development of perceptual-cognitive skill in young players, and future research should further investigate the development of these skills as well as their underlying factors in different kinds of sports.


Assuntos
Desempenho Atlético , Voleibol , Adolescente , Cognição , Tomada de Decisões , Feminino , Humanos
2.
J Sports Sci ; 39(17): 1911-1925, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33781180

RESUMO

In many sports, elite players outperform novices on tests for perceptual-cognitive skills, such as anticipation, decision-making and pattern recall. However, the developmental trajectory of these perceptual-cognitive skills has received limited attention. Therefore, this study examined the development of anticipation, decision-making and pattern recall in 202 female volleyball players aged between 7 and 26 years old. Participants were categorized into six age groups: U9, U11, U13, U15, U17 and Seniors. Using a video-based occlusion protocol, we assessed participants' ability to predict pass direction, decide the most optimal attack zone, or recall the opponents' defence positions. The results demonstrated that U17 and adult players had superior accuracy and shorter response times than younger players on all three tests. Notably, U9 players performed worse than older players on all tests. Binomial distributions showed that decision-making was above chance for U17 players and adults, whereas anticipation was above chance for almost all players. Our findings indicate that age-related improvements of perceptual-cognitive skills are evident at 11 years old. However, decision-making seems to develop considerably later than anticipation and pattern recall, suggesting different developmental trajectories for the different perceptual-cognitive skills. Longitudinal research regarding the development of perceptual-cognitive skills and their underlying mechanisms is warranted, as this could have important implications for talent detection and development.


Assuntos
Desempenho Atlético/psicologia , Cognição , Percepção Visual , Voleibol/psicologia , Adolescente , Adulto , Fatores Etários , Antecipação Psicológica , Atletas , Criança , Estudos Transversais , Feminino , Humanos , Rememoração Mental , Adulto Jovem
3.
Exp Brain Res ; 238(12): 2685-2699, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33079207

RESUMO

Several years ago, our research group forwarded a model of goal-directed reaching and aiming that describes the processes involved in the optimization of speed, accuracy, and energy expenditure Elliott et al. (Psychol Bull 136:1023-1044, 2010). One of the main features of the model is the distinction between early impulse control, which is based on a comparison of expected to perceived sensory consequences, and late limb-target control that involves a spatial comparison of limb and target position. Our model also emphasizes the importance of strategic behaviors that limit the opportunity for worst-case or inefficient outcomes. In the 2010 paper, we included a section on how our model can be used to understand atypical aiming/reaching movements in a number of special populations. In light of a recent empirical and theoretical update of our model Elliott et al. (Neurosci Biobehav Rev 72:95-110, 2017), here we consider contemporary motor control work involving typical aging, Down syndrome, autism spectrum disorder, and tetraplegia with tendon-transfer surgery. We outline how atypical limb control can be viewed within the context of the multiple-process model of goal-directed reaching and aiming, and discuss the underlying perceptual-motor impairment that results in the adaptive solution developed by the specific group.


Assuntos
Transtorno do Espectro Autista , Objetivos , Extremidades , Humanos , Movimento , Resolução de Problemas , Desempenho Psicomotor
4.
J Vis ; 18(2): 5, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29450501

RESUMO

An ability to predict the time-to-contact (TTC) of moving objects that become momentarily hidden is advantageous in everyday life and could be particularly so in fast-ball sports. Prediction motion (PM) experiments have sought to test this ability using tasks where a disappearing target moves toward a stationary destination. Here, we developed two novel versions of the PM task in which the destination either moved away from (Chase) or toward (Attract) the moving target. The target and destination moved with different speeds such that collision occurred 750, 1,000 or 1,250 ms after target occlusion. To determine if domain-specific experience conveys an advantage in PM tasks, we compared the performance of different sporting groups ranging from internationally competing athletes to non-sporting controls. There was no difference in performance between sporting groups and non-sporting controls but there were significant and independent effects on response error by target speed, destination speed, and occlusion period. We simulated these findings using a revised version of the linear TTC model of response timing for PM tasks (Yakimoff, Bocheva, & Mitrania, 1987; Yakimoff, Mateeff, Ehrenstein, & Hohnsbein, 1993) in which retinal input from the moving destination biases the internal representation of the occluded target. This revision closely reproduced the observed patterns of response error and thus describes a means by which the brain might estimate TTC when the target and destination are in motion.


Assuntos
Percepção de Movimento/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Adulto , Encéfalo/fisiologia , Feminino , Humanos , Modelos Lineares , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia , Adulto Jovem
5.
Cogn Process ; 18(1): 47-54, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27822605

RESUMO

An occlusion protocol was used to elucidate the respective roles of preprograming and online control during the quiet eye period of golf putting. Twenty-one novice golfers completed golf putts to 6-ft and 11-ft targets under full vision or with vision occluded on initiation of the backswing. Radial error (RE) was higher, and quiet eye was longer, when putting to the 11-ft versus 6-ft target, and in the occluded versus full vision condition. Quiet eye durations, as well as preprograming, online and dwell durations, were longer in low-RE compared to high-RE trials. The preprograming component of quiet eye was significantly longer in the occluded vision condition, whereas the online and dwell components were significantly longer in the full vision condition. These findings demonstrate an increase in preprograming when vision is occluded. However, this was not sufficient to overcome the need for online visual control during the quiet eye period. These findings suggest the quiet eye period is composed of preprograming and online control elements; however, online visual control of action is critical to performance.


Assuntos
Desempenho Atlético/fisiologia , Golfe , Desempenho Psicomotor/fisiologia , Percepção Visual/fisiologia , Adulto , Humanos
6.
Brain Cogn ; 104: 25-33, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26897261

RESUMO

We examined whether the temporal representation developed during motor training with reduced-frequency knowledge of results (KR; feedback available on every other trial) was transferred to an imitation learning task. To this end, four groups first practised a three-segment motor sequence task with different KR protocols. Two experimental groups received reduced-frequency KR, one group received high-frequency KR (feedback available on every trial), and one received no-KR. Compared to the no-KR group, the groups that received KR learned the temporal goal of the movement sequence, as evidenced by increased accuracy and consistency across training. Next, all groups learned a single-segment movement that had the same temporal goal as the motor sequence task but required the imitation of biological and nonbiological motion kinematics. Kinematic data showed that whilst all groups imitated biological motion kinematics, the two experimental reduced-frequency KR groups were on average ∼ 800 ms more accurate at imitating movement time than the high-frequency KR and no-KR groups. The interplay between learning biological motion kinematics and the transfer of temporal representation indicates imitation involves distinct, but complementary lower-level sensorimotor and higher-level cognitive processing systems.


Assuntos
Comportamento Imitativo/fisiologia , Conhecimento Psicológico de Resultados , Aprendizagem/fisiologia , Movimento , Transferência de Experiência , Adolescente , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Destreza Motora , Distribuição Aleatória , Adulto Jovem
7.
Psychol Res ; 80(4): 487-95, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25894232

RESUMO

Cyclical upper limb movement can involuntarily deviate from its primary movement axis when the performer concurrently observes incongruent biological motion (i.e. interpersonal observation-execution). The current study examined the social modulation of such involuntary motor interference using a protocol that reflected everyday social interactions encountered in a naturalistic social setting. Eighteen participants executed cyclical horizontal arm movements during the observation of horizontal (congruent) or curvilinear (incongruent) biological motion. Both prior to, and during the interpersonal observation-execution task, participants also received a series of social words designed to prime a pro-social or anti-social attitude. The results showed greater orthogonal movement deviation, and thus interference, for the curvilinear compared to horizontal stimuli. Importantly, and opposite to most of the previous findings from work on automatic imitation and mimicry, there was a greater interference effect for the anti-social compared to pro-social prime condition. These findings demonstrate the importance of interpreting the context of social primes, and strongly support predictions of a comparison between the prime construct and the self-concept/-schema and the top-down response modulation of social incentives.


Assuntos
Atenção/fisiologia , Comportamento Imitativo/fisiologia , Percepção de Movimento/fisiologia , Análise e Desempenho de Tarefas , Adulto , Feminino , Humanos , Relações Interpessoais , Masculino , Movimento (Física) , Movimento/fisiologia , Desempenho Psicomotor/fisiologia
8.
Exp Brain Res ; 233(1): 253-61, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25266716

RESUMO

The current study examined temporal estimation in a prediction motion task where participants were cued to overtly pursue one of two moving objects, which could either arrive first, i.e., shortest [time to contact (TTC)] or second (i.e., longest TTC) after a period of occlusion. Participants were instructed to estimate TTC of the first-arriving object only, thus making it necessary to overtly pursue the cued object while at the same time covertly pursuing the other (non-cued) object. A control (baseline) condition was also included in which participants had to estimate TTC of a single, overtly pursued object. Results showed that participants were able to estimate the arrival order of the two objects with very high accuracy irrespective of whether they had overtly or covertly pursued the first-arriving object. However, compared to the single-object baseline, participants' temporal estimation of the covert object was impaired when it arrived 500 ms before the overtly pursued object. In terms of eye movements, participants exhibited significantly more switches in gaze location during occlusion from the cued to the non-cued object but only when the latter arrived first. Still, comparison of trials with and without a switch in gaze location when the non-cued object arrived first indicated no advantage for temporal estimation. Taken together, our results indicate that overt pursuit is sufficient but not necessary for accurate temporal estimation. Covert pursuit can enable representation of a moving object's trajectory and thereby accurate temporal estimation providing the object moves close to the overt attentional focus.


Assuntos
Atenção/fisiologia , Julgamento/fisiologia , Percepção de Movimento/fisiologia , Percepção do Tempo/fisiologia , Sinais (Psicologia) , Movimentos Oculares/fisiologia , Humanos , Masculino , Movimento (Física) , Estimulação Luminosa , Tempo de Reação/fisiologia , Adulto Jovem
9.
Psychol Res ; 79(4): 621-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24947759

RESUMO

Increased involuntary arm movement deviation when observing an incongruent human arm movement has been interpreted as a strong indicator of motor contagion. Here, we examined the contribution of trajectory and end-point information on motor contagion by altering congruence between the stimulus and arm movement. Participants performed cyclical horizontal arm movements whilst simultaneously observing a stimulus representing human arm movement. The stimuli comprised congruent horizontal movements or vertical movements featuring incongruent trajectory and end-points. A novel, third, stimulus comprised curvilinear movements featuring congruent end-points, but an incongruent trajectory. In Experiment 1, our dependent variables indicated increased motor contagion when observing the vertical compared to horizontal movement stimulus. There was even greater motor contagion in the curvilinear stimulus condition indicating an additive effect of an incongruent trajectory comprising congruent end-points. In Experiment 2, this additive effect was also present when facing perpendicular to the display, and thus with end-points represented as a product of the movement rather than an external spatial reference. Together, these findings support the theory of event coding (Hommel et al., Behav Brain Sci 24:849-878, 2001), and the prediction that increased motor contagion takes place when observed and executed actions share common features (i.e., movement end-points).


Assuntos
Atividade Motora/fisiologia , Desempenho Psicomotor/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Braço , Feminino , Humanos , Masculino , Adulto Jovem
10.
J Neuroeng Rehabil ; 11: 112, 2014 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-25055852

RESUMO

BACKGROUND: Upper limb motor control in fast, goal-directed aiming is altered in tetraplegics following posterior-deltoid musculotendinous transfer. Specifically, movements have similar end-point accuracy but longer duration and lower peak velocity than those of age-matched, neurotypical controls. Here, we examine in detail the interplay between primary movement and submovement phases in five C6 tetraplegic and five control participants. METHODS: Aiming movements were performed in two directions (20 cm away or toward), with or without vision. Trials that contained a submovement phase (i.e., discontinuity in velocity, acceleration or jerk) were identified. Discrete kinematic variables were then extracted on the primary and submovements phases. RESULTS: The presence of submovements did not differ between the tetraplegic (68%) and control (57%) groups, and almost all submovements resulted from acceleration and jerk discontinuities. Tetraplegics tended to make a smaller amplitude primary movement, which had lower peak velocity and greater spatial variability at peak velocity. This was followed by a larger amplitude and longer duration secondary submovement. Peak velocity of primary movement was not related to submovement incidence. Together, the primary and submovement phases of both groups were equally effective in reducing end-point error. CONCLUSIONS: C6 tetraplegic participants exhibit some subtle differences in measures of motor behaviour compared to control participants, but importantly feedforward and feedback processes work effectively in combination to achieve accurate goal-directed aiming.


Assuntos
Músculo Deltoide/transplante , Movimento/fisiologia , Quadriplegia/fisiopatologia , Quadriplegia/cirurgia , Adulto , Vértebras Cervicais , Humanos , Masculino
11.
Sci Rep ; 14(1): 9996, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693184

RESUMO

Tracking a moving object with the eyes seems like a simple task but involves areas of prefrontal cortex (PFC) associated with attention, working memory and prediction. Increasing the demand on these processes with secondary tasks can affect eye movements and/or perceptual judgments. This is particularly evident in chronic or acute neurological conditions such as Alzheimer's disease or mild traumatic brain injury. Here, we combined near infrared spectroscopy and video-oculography to examine the effects of concurrent upper limb movement, which provides additional afference and efference that facilitates tracking of a moving object, in a novel dual-task pursuit protocol. We confirmed the expected effects on judgement accuracy in the primary and secondary tasks, as well as a reduction in eye velocity when the moving object was occluded. Although there was limited evidence of oculo-manual facilitation on behavioural measures, performing concurrent upper limb movement did result in lower activity in left medial PFC, as well as a change in PFC network organisation, which was shown by Graph analysis to be locally and globally more efficient. These findings extend upon previous work by showing how PFC is functionally organised to support eye-hand coordination when task demands more closely replicate daily activities.


Assuntos
Córtex Pré-Frontal , Extremidade Superior , Humanos , Córtex Pré-Frontal/fisiologia , Masculino , Feminino , Extremidade Superior/fisiologia , Adulto , Adulto Jovem , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Movimentos Oculares/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho , Atenção/fisiologia
12.
PLoS One ; 18(4): e0284936, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37093873

RESUMO

The tendency to involuntarily imitate the actions of others (automatic imitation) can be modulated by social affiliative cues. Here, we explored whether the disruption to our social lives caused by the COVID-19 pandemic may subsequently influence automatic imitation. Three groups were initially presented a sentence comprehension task that featured either neutral (control), safe or unsafe primes to COVID-19 infection. They then completed an automatic imitation task, where a numeric cue was presented alongside apparent motion of an index or middle finger, which was either compatible or incompatible with the required response. Reaction times were longer for the incompatible compared to compatible trials, and thus demonstrated automatic imitation. However, there was no influence of the primes indicating that automatic imitation was unaffected by the risk of COVID-19. The potential theoretical explanations and practical implications of pathogen avoidance and social bonding incentives are discussed with reference to pandemic events.


Assuntos
COVID-19 , Comportamento Imitativo , Humanos , Comportamento Imitativo/fisiologia , Pandemias , Tempo de Reação , Sinais (Psicologia)
13.
Autism Res ; 16(9): 1799-1810, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37534381

RESUMO

Observing and voluntarily imitating the biological kinematics displayed by a model underpins the acquisition of new motor skills via sensorimotor processes linking perception with action. Differences in voluntary imitation in autism could be related to sensorimotor processing activity during action-observation of biological motion, as well as how sensorimotor integration processing occurs across imitation attempts. Using an observational practice protocol, which minimized the active contribution of the peripheral sensorimotor system, we examined the contribution of sensorimotor processing during action-observation. The data showed that autistic participants imitated both the temporal duration and atypical kinematic profile of the observed movement with a similar level of accuracy as neurotypical participants. These findings suggest the lower-level perception-action processes responsible for encoding biological kinematics during the action-observation phase of imitation are operational in autism. As there was no task-specific engagement of the peripheral sensorimotor system during observational practice, imitation difficulties in autism are most likely underpinned by sensorimotor integration issues related to the processing of efferent and (re)afferent sensorimotor information during trial-to-trial motor execution.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Fenômenos Biomecânicos , Aprendizagem , Desempenho Psicomotor , Comportamento Imitativo
14.
Exp Brain Res ; 216(3): 445-55, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22116400

RESUMO

The current study examined the movement kinematics of older adults when aiming to vertically oriented targets. Late middle-age and early old-age participants completed 20 trials to a small target located downward or upward by 0.16 m from a home position at shoulder height. Aiming direction had a significant effect, resulting in more submovements, which were mostly reflective of undershooting when aiming to the downward compared to upward target. In trials containing a submovement, both groups exhibited shorter total movement time, concomitant with a decrease in duration of the primary movement and an increase in submovement amplitude, when aiming to the downward target. Measures of dispersion also differed in accord with the amplitude of submovements, such that there was greater spatial and temporal variability in the primary movement when aiming in the downward direction. While there was limited evidence of a difference between the groups, there were significant correlations between age and several dependent measures when aiming to the downward target. Of note, in trials containing submovements, older participants exhibited larger amplitude and longer duration submovements, as well as shorter amplitude primary movement. Spatial variability at peak velocity also increased as a function of age when aiming downward, but not in trials without submovements. An explanation related to physical limits on movement production is discounted given the lack of consistent findings between trial types. Instead, we suggest older participants' exhibit strategic differences in movement kinematics when aiming to vertically located targets, and that these change progressively with age in order to maintain speed-accuracy relations.


Assuntos
Envelhecimento , Movimentos Oculares/fisiologia , Movimento/fisiologia , Orientação/fisiologia , Desempenho Psicomotor/fisiologia , Adaptação Fisiológica/fisiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos
15.
Exp Brain Res ; 221(4): 459-66, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22821082

RESUMO

We examined the hypothesis that different processes and representations are associated with the learning of a movement sequence through motor-execution and action-observation. Following a pre-test in which participants attempted to achieve an absolute, and relative, time goal in a sequential goal-directed aiming movement, participants received either physical or observational practice with feedback. Post-test performance indicated that motor-execution and action-observation participants learned equally well. Participants then transferred to conditions where the gain between the limb movements and their visual consequences were manipulated. Under both bigger and smaller transfer conditions, motor-execution and action-observation participants exhibited similar intramanual transfer of absolute timing. However, participants in the action-observation group exhibited superior transfer of relative timing than the motor-execution group. These findings suggest that learning via action-observation is underpinned by a visual-spatial representation, while learning via motor-execution depends more on specific force-time planning (feed forward) and afferent processing associated with sensorimotor feedback. These behavioural effects are discussed with reference to neural processes associated with striatum, cerebellum and motor cortical regions (pre-motor cortex; SMA; pre-SMA).


Assuntos
Potenciais de Ação/fisiologia , Retroalimentação Sensorial/fisiologia , Lateralidade Funcional/fisiologia , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Transferência de Experiência/fisiologia , Adolescente , Extremidades/inervação , Extremidades/fisiologia , Feminino , Humanos , Masculino , Músculo Esquelético/inervação , Músculo Esquelético/fisiologia , Estimulação Luminosa/métodos , Adulto Jovem
16.
J Vis ; 12(13): 17, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23262149

RESUMO

Smooth pursuit during prolonged occlusion is improved in the presence of sensorimotor signals when tracking self-generated target motion. The current study investigated whether concurrent arm tracking of externally-generated target motion conveys a similar facilitation to ocular pursuit of transiently occluded constant velocity (Experiment 1) or accelerating (Experiment 2) targets. Velocity characteristics and occlusion duration were arranged in random or blocked order, thus permitting a novel examination of the contribution from sensorimotor signals and predictive processes acting within the ocular system during transient occlusion. Consistent with previous investigations, smooth pursuit decayed during transient occlusion; but eye velocity was higher when trials were presented in blocked compared to random order, particularly for positively accelerating targets. For fast, constant velocity targets, concurrent arm movement facilitated smooth pursuit during transient occlusion. Nevertheless, even with increased predictability regarding the upcoming target motion in blocked-order trials and the presence of sensorimotor signals from concurrent arm movement, eye velocity always remained less than target velocity during occlusion. This contrasted with the manual response, which attained velocity close to target velocity, whether in blocked or random conditions. These findings are discussed with reference to recent models of ocular pursuit that incorporate short-term and/or long-term prediction to account for target extrapolation during occlusion.


Assuntos
Atenção/fisiologia , Percepção de Movimento/fisiologia , Movimento (Física) , Acompanhamento Ocular Uniforme/fisiologia , Tempo de Reação/fisiologia , Extremidade Superior/fisiologia , Volição/fisiologia , Adulto , Fixação Ocular , Humanos , Estimulação Luminosa
17.
Am J Psychol ; 125(1): 9-23, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22428422

RESUMO

This article celebrates the contribution that the American Journal of Psychology (AJP) has made to the area of perceptual-motor skill over its 125-year history. We highlight the articles published in AJP and trace the technical and theoretical developments that stem from this groundbreaking work. Included in our overview are AJP articles on the excitability of the motor system, motor learning, adaptation to visual rearrangement, the ecological approach to perception and action, and the measurement of human handedness. We conclude by identifying a number of areas associated with perceptual-motor skill where AJP continues to make an important contribution.


Assuntos
Aprendizagem , Publicações Periódicas como Assunto/história , Desempenho Psicomotor , Percepção Visual , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Pesquisa/história
18.
Hum Mov Sci ; 81: 102917, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34954624

RESUMO

The accuracy and precision of target-directed aiming is contingent upon the availability of online visual feedback. The present study aimed to examine the visual regulation of aiming with blurred vision. The aiming task was executed using a stylus on a graphics digitizing board, which was translated onto a screen in the form of a cursor (representing the moving limb) and target. The vision conditions involved the complete disappearance or blur of the cursor alone, target alone, and cursor+target. These conditions involved leaving the screen uncovered or covering with a diffusing sheet to induce blur. The distance between the screen and sheet was increased to make the blur progressively more severe (0 cm, 3 cm). Results showed significantly less radial and variable error under blurred compared to no vision of the cursor and cursor+target. These findings were corroborated by the movement kinematics including a shorter proportion of time to peak velocity, more negative within-participant correlation between the distances travelled to and after peak velocity, and lower spatial variability from peak velocity to the end of the movement under blurred vision. The superior accuracy and precision under the blurred compared to no vision conditions is consistent with functioning visual regulation of aiming, which is primarily contingent upon the online visual feedback of the moving limb. This outcome may be attributed to the processing of low spatial-high temporal frequencies. Potential implications for low vision diagnostics are discussed.


Assuntos
Retroalimentação Sensorial , Movimento , Fenômenos Biomecânicos , Retroalimentação , Humanos , Desempenho Psicomotor , Visão Ocular , Percepção Visual
19.
Front Psychol ; 13: 902043, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248589

RESUMO

It has been reported that behavior of experts and novices in various sporting tasks is impervious to the introduction of blur. However, studies have used diverse methods of blurring the visual stimulus (i.e., dioptric blur and Gaussian blur), and tasks that did not always preserve the normal perception-action coupling. In the current study, we developed a novel experimental protocol to examine the effect of different levels of Gaussian blur on interception performance and eye gaze data using an immersive VR task. Importantly, this provided a realistic simulation of a real-world boxing scenario (e.g., the presence of a feint prior to the onset of different combinations of punches) in which expert combat athletes (n = 18) experienced a first-person, adaptive viewpoint of the visual environment, which could be blurred according to their gaze location (central blur, peripheral blur, no blur). We found that participants exhibited similar interception performance in the presence of central blur or peripheral blur compared to a control condition with no blur. However, interception performance was significantly better with a central blur compared to peripheral blur. Eye gaze data indicated that although participants fixated at similar areas of interest irrespective of the presence of blur, fixation duration was significantly longer with a strong level of blur in the peripheral viewing condition than all levels of central blur and the control condition. These findings can be explained by relocating attention to different areas of the environment, which thereby influenced the perception of salient information. Participants also performed better on the first punch of a sequence preceded by a foot feint compared to arm feint or no feint. Still, irrespective of feint type, performance was significantly better on the second and third punch compared to the first punch. These findings are consistent with participants using additional information from the opponent's body movements and situational probabilities to increase performance as the sequence of punches developed. Overall, these are the first evidence for the use of VR as a means to examine gaze-contingent manipulations of the environment, and hence highlight the potential for facilitating learning and transfer to a real sporting situations.

20.
Exp Brain Res ; 214(4): 483-90, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21877101

RESUMO

This study examined how explicit advance knowledge might influence adaptive behavior to visual occlusions. Catching performance and kinematics of good ball catchers were compared between no, early and late occlusion trials. Discrete visual occlusions of 400 ms, occurring early or late in the ball's approach trajectory, were randomly interspersed between no occlusion trials. In one condition, the presence and type of occlusion were announced a priori (expected), whereas in another condition no such information was provided (unexpected). Expectation of occlusion resulted in an adapted limb transport and increased grasping time, whereas in the unexpected condition a higher peak of wrist velocity was evident for all occlusion conditions. The observed different adaptations cannot be explained by trial-by-trial adaptations alone and instead provide evidence for the influence of explicit advance knowledge in the motor response of interceptive actions.


Assuntos
Adaptação Fisiológica/fisiologia , Antecipação Psicológica/fisiologia , Percepção de Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Privação Sensorial/fisiologia , Humanos , Masculino , Tempo de Reação/fisiologia , Adulto Jovem
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