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The coordination of the oculomotor and manual effector systems is an important component of daily motor behavior. Previous work has primarily examined oculomotor/manual coordination in discrete targeting tasks. Here we extend this...
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The coordination of the oculomotor and manual effector systems is an important component of daily motor behavior. Previous work has primarily examined oculomotor/manual coordination in discrete targeting tasks. Here we extend this work to learning a tracking task that requires continuous response and movement update. Over two sessions, participants practiced controlling a computer mouse with movements of their arm to follow a target moving in a repeated sequence. Eye movements were also recorded. In a retention test, participants demonstrated sequence-specific learning with both effector systems, but differences between effectors also were apparent. Time series analysis and multiple linear regression were employed to probe spatial and temporal contributions to overall tracking accuracy within each effector system. Sequence-specific oculomotor learning occurred only in the spatial domain. By contrast, sequence-specific learning at the arm was evident only in the temporal domain. There was minimal interdependence in error rates for the two effector systems, underscoring their independence during tracking. These findings suggest that the oculomotor and manual systems learn contemporaneously, but performance improvements manifest differently and rely on different elements of motor execution. The results may in part be a function of what the motor learning system values for each effector as a function of its effector’s inertial properties. Keywords Visual motor coordination - Learning - Motor skills
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We present results from five search experiments using a novel 'unpacking' paradigm in which participants use a mouse to sort through random heaps of distractors to locate the target. We report that during this task participants of...
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We present results from five search experiments using a novel 'unpacking' paradigm in which participants use a mouse to sort through random heaps of distractors to locate the target. We report that during this task participants often fail to recognize the target despite moving it, and despite having looked at the item. Additionally, the missed target item appears to have been processed as evidenced by post-error slowing of individual moves within a trial. The rate of this 'unpacking error' was minimally affected by set size and dual task manipulations, but was strongly influenced by perceptual difficulty and perceptual load. We suggest that the error occurs because of a dissociation between perception for action and perception for identification, providing further evidence that these processes may operate relatively independently even in naturalistic contexts, and even in settings like search where they should be expected to act in close coordination.
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PURPOSE: Although visual analysis, motor coordination, and visual-motor integration can each affect performance on a test of visual motor integration, previous studies have not reported the relative importance of these components ...
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PURPOSE: Although visual analysis, motor coordination, and visual-motor integration can each affect performance on a test of visual motor integration, previous studies have not reported the relative importance of these components to the relation between visual motor integration and learning readiness, reading, and math. This investigation relates academic achievement in reading and math to performance on the Beery-Buktenica Developmental Test of Visual-Motor Integration (VMI) and its subtests, Visual Perception and Motor Coordination. METHODS: The VMI was administered to 155 children in second through fourth grades (7 to 10 years of age; mean, 8.4 +/- 1.0 years). The Otis-Lennon School Ability Test and Stanford Achievement Test were administered by the school. RESULTS: A significant difference was found in performance on the VMI and Visual Perception and Motor Coordination subtests between children in the upper and lower quartiles in reading (p = 0.020, p < 0.001, and p = 0.027, respectively) and math achievement (p = 0.004, p < 0.001, and p = 0.01, respectively). The VMI standard score was significantly correlated with Stanford total math standard score (p = 0.001) and a trend toward significance was found for Stanford reading score (p = 0.050) while partially controlling for verbal school ability and age. In addition, Visual Perception and Motor Coordination standard scores were significantly related to Stanford math (p < 0.001 and p = 0.005, respectively) and reading score (p = 0.008 and p = 0.027, respectively) after partially controlling for verbal school ability and age. Multiple linear regressions controlling for performance on the VMI and each subtest, as well as age and verbal cognitive ability, showed a significant relation between the Visual Perception subtest score and math achievement. CONCLUSION: Visual perceptual ability should be assessed in children with poor math and/or reading achievement.
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Voluntary locomotion is one of the most important motor actions performed by animals, including humans, and vision plays an important role in controlling such action. We conducted cross-sectional (Experiment 1) and longitudinal (E...
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Voluntary locomotion is one of the most important motor actions performed by animals, including humans, and vision plays an important role in controlling such action. We conducted cross-sectional (Experiment 1) and longitudinal (Experiment 2) investigations and found that the perception of visual motion (optic flow), a critical cue for perceiving and controlling the direction of locomotion, drastically changes just before the emergence of locomotion in infancy. The results suggest that developmental change in particular visual perceptions precedes and potentially promotes the emergence of related motor actions in early development. Our findings offer a new perspective on the development of visuomotor coordination, which has long been thought to derive from the development of motor actions rather than from changes in visual perceptions.
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Asymmetrically placed visual distractors are known to cause a lateral bias in the execution of a movement directed toward a target. The aim of the present experiment was to verify if the trajectory of the ball and the trajectory o...
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Asymmetrically placed visual distractors are known to cause a lateral bias in the execution of a movement directed toward a target. The aim of the present experiment was to verify if the trajectory of the ball and the trajectory of the jump for a basket-shot can be affected by the sole position of a second player, who stays in front of the shooting player in one of three possible positions (centre, left or right) but too far to physically interfere with the shot. Young basketball players were asked to perform 60 shots at 6.25 m from a regular basket, with or without a second player staying in front of them in, alternately, a centre, left or right position. A computerised system measured the angular deviation of the jump direction from the vertical direction and the lateral deviation of the ball trajectory from the midline. The results showed that both the jump direction and the entry position of the ball deviated toward the opposite side from the second player's side; however, these effects were too small to significantly affect the mean goal percentage. This result confirms that some placements of the players can have an effect as visual distractors. Further studies are necessary to find what game conditions can make such distractors harmful for the athletic performance.
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There is disagreement about the effectiveness of observational practice for the acquisition of novel coordination skills and the type of processes involved in observation of novel movements. In this study, we examined learning of ...
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There is disagreement about the effectiveness of observational practice for the acquisition of novel coordination skills and the type of processes involved in observation of novel movements. In this study, we examined learning of a bimanual 90° phase offset through comparisons of three groups; physical practice, observational practice and no practice (n = 12/group). Groups were compared before and after practice on perception and production scans of the practised pattern. The observation group was yoked to the physical group such that observers watched repeated demonstrations of a learning model. Although there were no positive effects of observational practice for physical performance measures, the observation group did not differ from the physical practice group and was more accurate than controls on perceptual discrimination measures after practice. We concluded that observation of a novel bimanual movement can aid perception but that physical practice is necessary for immediate physical performance benefits. These results are discussed in terms of cognitive mediation models of motor skill learning.
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From tying your shoes and clipping your tie to the claps at the end of a fine seminar, bimanual coordination plays a major role in our daily activities. An important phenomenon in bimanual coordination is the predisposition toward...
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From tying your shoes and clipping your tie to the claps at the end of a fine seminar, bimanual coordination plays a major role in our daily activities. An important phenomenon in bimanual coordination is the predisposition toward mirror symmetry in the performance of bimanual rhythmic movements. Although learning and adaptation in bimanual coordination are phenomena that have been observed, they have not been studied in the context of adaptive control and internal representations—approaches that were successfully employed in the arena of reaching movements and adaptation to force perturbations. In this paper we examine the dynamics of the learning mechanisms involved when subjects are trained to perform a bimanual non-harmonic polyrhythm in a bimanual index finger tapping task. Subjects are trained in this task implicitly, using altered visual feedback, while their performance is continuously monitored throughout the experiment. Our experimental results indicate the existence of significant (p<<0.01) learning curves (i.e., error plots with significantly negative slopes) during training and aftereffects with a washout period after the visual feedback ceases to be altered. These results confirm the formation of internal representations in bimanual motor control. We present a simple, physiologically plausible, neural model that combines feedback and adaptation in the control process and which is able to reproduce key phenomena of bimanual coordination and adaptation.
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Abstract When engaging in manual or visual tasks while sitting, infants modify their postural sway based on concurrent task demands. It remains unclear whether these modulations are sensitive to differences in concurrent task dema...
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Abstract When engaging in manual or visual tasks while sitting, infants modify their postural sway based on concurrent task demands. It remains unclear whether these modulations are sensitive to differences in concurrent task demands (holding a toy vs. looking at a toy being held by someone else), and whether the properties of the support surface impact these adaptations. We investigated infants’ ability to modify postural sway when holding a toy or visually attending to a toy someone else was holding while sitting on different support surfaces. Twenty‐six independently sitting infants sat on solid and compliant surfaces placed on a force plate while looking at or holding a toy. Measures of postural sway were calculated from the center of pressure data. Visually attending to a toy was associated with less sway and lower sway velocity than when holding a toy. Surprisingly, surface compliance did not affect sway and there were no interaction effects. Whereas sway modulations may facilitate infants’ performance on both manual and visual concurrent tasks, the visual task placed more constraints on the postural system leading to greater adaptations in postural sway. These findings provide insights into how infants are allocating attention and coordinating perceptual‐motor information in developing sitting skills.
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Patients with chronic ankle instability (CAI) have demonstrated sensorimotor impairments. Submaximal force steadiness and accuracy measure sensory, motor, and visual function via a feedback mechanism, which helps researchers and c...
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Patients with chronic ankle instability (CAI) have demonstrated sensorimotor impairments. Submaximal force steadiness and accuracy measure sensory, motor, and visual function via a feedback mechanism, which helps researchers and clinicians comprehend the sensorimotor deficits associated with CAI. To determine if participants with CAI experienced deficits in hip and ankle submaximal force steadiness and accuracy compared with healthy control participants. Case-control study. Research laboratory. Twenty-one patients with CAI and 21 uninjured individuals. Maximal voluntary isometric contraction (MVIC) and force steadiness and accuracy (10% and 30% of MVIC) of the ankle evertors and invertors and hip abductors were assessed using the central 10 seconds (20%-87% of the total time) of the 3 trials. Relative to the control group, the CAI group demonstrated less accuracy of the invertors (P < .001). Across all motions, the CAI group showed less steadiness (P < .001) and less accuracy (P < .01) than the control group at 10% of MVIC. For MVIC, the CAI group displayed less force output in hip abduction than the uninjured group (P < .0001). Patients with CAI were unable to control ongoing fine force (10% and 30% of MVIC) through a feedback mechanism during an active test. These findings suggested that deficits in sensorimotor control predisposed patients with CAI to injury positions because they had difficulty integrating the peripheral information and correcting their movements in relation to visual information.
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Recent research has shown that Developmental coordination disorder (DCD) can present with some similar symptomology as Autism Spectrum Conditions (ASC). This paper therefore explored the similarities and differences in coordinatio...
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Recent research has shown that Developmental coordination disorder (DCD) can present with some similar symptomology as Autism Spectrum Conditions (ASC). This paper therefore explored the similarities and differences in coordination and sensory responsivity between DCD and ASC. 77 children took part: 42 (35 male, 7 female) with ASC (ages 7-21: mean age 12.23 years), 26 (19 male, 7 female) with DCD (ages 7-21; mean age 11.07 years) and 9 (2 male, 7 female) with ASC and DCD (ages 8-15; mean age 12.27). All groups completed a battery of validated parent report measures online that included motor coordination (DCDQ), sensory responsivity (SPC-R) and social communication measures (AQ). Results showed no significant differences in coordination, and some significant differences in sensory responsivity between ASC and DCD (increased visual and auditory responsivity and decreased proprioception). Exploratory analysis showed that these differences showed good validity in identifying the diagnosis of ASC and DCD. These results elucidate the underlying causes of motor coordination difficulties in both conditions. Specifically, ASC coordination difficulties appear linked to visual processing impairments, whilst DCD coordination difficulties appear to be linked to spatial processing. This may aid better diagnosis and intervention for these conditions.
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