Postural Control during Progressively Increased Balance-Task Difficulty in Athletes with Unilateral Transfemoral Amputation: Effect of Ocular Mobility and Visuomotor Processing

This study examined postural control during single leg stance test with progressively increased balance-task difficulty in soccer players with unilateral transfemoral amputation (n = 11) compared to able-bodied soccer players (n = 11). The overall stability index (OSI), the anterior/posterior stability index, and the medial/lateral stability index during three balance tasks with increasing surface instability were estimated. The oculomotor and visuomotor contribution to postural control in disabled athletes was analyzed. Oculomotor function, simple and choice reaction times, and peripheral perception were assessed in a series of visuomotor tests. The variation in OSI demonstrated significantly greater increases during postural tests with increased balance-task difficulty in the able-bodied soccer players compared to amputees (F(2,40) = 3.336, p < 0.05). Ocular mobility index correlated (p < 0.05) with OSI in conditions of increasing balance-task difficulty. Moreover, speed of eye-foot reaction has positive influence (p < 0.05) on stability indexes in tasks with an unstable surface. Amputee soccer players displayed comparable postural stability to able-bodied soccer players. Disabled athletes had better adaptability in restoring a state of balance in conditions of increased balance-task difficulty than the controls. The speed of visuomotor processing, characterized mainly by speed of eye-foot reaction, significantly contributed to these results.

Predicting Visual-Motor Performance in a Reactive Agility Task from Selected Demographic, Training, Anthropometric, and Functional Variables in Adolescents

Reactive agility (RA) directly refers to athletes’ visuomotor processing of the specific conditions for team sports. The aim of the study was to identify the factors among age, gender, sport discipline, time participation in a sports activity, reaction time, and visual field which could have an impact on visual-motor performance in RA tasks in young, competitive team sports players. The study included boys (n = 149) and girls (n = 157) aged 13–15 participating in basketball, volleyball and handball. Anthropometric measurements were carried out, and the Peripheral Perception (PP) test was used to evaluate the visual-motor performance under laboratory conditions. The Five-Time Shuttle Run to Gates test was used to determine the RA. A multiple regression analysis was performed to identify the relationships between the visual-motor performance in an RA task (dependent variable) and the remaining independent variables (continuous and categorical). The findings of the current study indicate that the main predictive factors of visual-motor performance in RA among young athletes are gender (ß = −0.46, p < 0.000) and age (ß = −0.30, p < 0.000). Moreover, peripheral perception positively affected the achievements in the RA task in boys (ß = −0.25, p = 0.020). The sport discipline does not differentiate the visual-motor performance in RA in team sports players in the puberty period.

Exercise-induced fatigue impairs visuomotor adaptability in physical education students

Purpose: Physical exercise has been shown to exert various effects on visuomotor processing and motor learning. The present study aimed to examine the impact of exercise with progressively increased physical load on consecutive stages of perceptual-motor learning. We compared the effectiveness of visuomotor adaptability in four subsequent trials during a complex coordination task performed in different conditions, including under conditions of progressively increased physical load, and in non-exercise resting control conditions. Material: Twenty-seven physical education university students participated in this study. Participants were randomly assigned to one of two group: (1) an exercise experimental group (n = 14), or (2) a non-exercise resting control group (n = 13). Methods: Participants in the experimental group performed three 10-minute effort-tests with increasing intensity on a cycloergometer. Each participant was assigned individual workload values below the lactate threshold (40% VO2max), at the lactate threshold (60% VO2max), and above the lactate threshold (80% VO2max). Four sessions of the two-hand coordination test included in the Vienna Test System were used to examine visuomotor adaptability variation. The total time duration, total error duration, and coordination difficulty were analyzed. Results: There was a significant interaction between number of test repetitions and group (experimental, control) for total duration ( F (3,75) = 3.54, p = 0.018). In particular, there was a significant reduction ( p = 0.006) in duration in the control group after fourth test repetitions as compared to the baseline. In the experimental group, in contrast, there was a tendency for duration to increase after exercise above the lactate threshold intensity. There was also a significant interaction between test repetitions and group for total error duration ( F (3,75) = 3.14, p = 0.03). Conclusions: The results suggest that high intensity exercise can disrupt visuomotor processing during complex skill acquisition. These findings highlight the interplay between exercise intensity and motor control and learning, which in turn, has practical implications for developing and improving motor training and physical education programs.

On the evolution of neural decisions from uncertain visual input to uncertain actions

Behavior can be conceived as the result of a sequence in which the outcomes of perceptual decisions inform decisions on which action to take. However, the relationship between these processes, and spatiotemporal dynamics of the visual-to-motor transformation remains unclear. Here, we combined accumulation-to-threshold models and electro-magnetoencephalography, to trace neural correlates of sensorimotor decisions in space, time and frequency. We challenge the assumption of sequential decisions, with evidence that visuomotor processing unfolds through a continuous flow of information from sensory to motor regions. Action selection is initiated before regional visual decisions are completed. By linking behavior and physiology through theoretical decision models, we identify simultaneous forward and backward flow of information for visuomotor decisions between sensory and motor regions, in beta and gamma ranges. The model of integrated visuomotor decisions provides a powerful approach to investigate behavioral disorders that impair the ability to use sensory inputs to guide appropriate actions.

Comparing three portable, tablet-based visuomotor tasks to laboratory versions: An assessment of test validity

The assessment of visuomotor function can provide important information about neurological status. Many tasks exist for testing visuomotor function in the laboratory, but the availability of portable, easy-to-use versions that allow reliable, accurate, and precise measurement of movement timing and accuracy has been limited. We developed a tablet application that uses three laboratory visuomotor tests: the double-step task, interception task, and stop-signal task. We asked the participants to perform both the lab and tablet versions of each task and compared their response patterns across equipment types to assess the validity of the tablet versions. On the double-step task, the participants adjusted to the displaced target adequately in both the lab and tablet versions. On the interception task, the participants intercepted nonaccelerating targets and performed worse on accelerating targets in both versions of the task. On the stop-signal task, the participants successfully inhibited their reaching movements on short stop-signal delays (50–150 ms) more frequently than on long stop-signal delays (200 ms) in both versions of the task. Our findings suggest that the tablet version of each task assesses visuomotor processing in the same way as their respective laboratory version, thus providing the research community with a new tool to assess visuomotor function.