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Published on: March 21, 2019
Influence of accuracy constraints on bimanual coordination during a goal-directed task in children with hemiplegic
Ya-Ching Hung1, Jeanne Charles, Andrew M Gordon
1Department of Family, Nutrition, and Exercise Sciences, Queens College, City University of New York, 65-30 Kissena Blvd, Flushing, NY 11367, USA. yaching.hung@qc.cuny.edu
Insights
Children with hemiplegic cerebral palsy (CP) show altered bimanual coordination. Higher accuracy demands can hinder their performance on tasks, suggesting that increased constraints are not always beneficial for upper extremity function.
Area of Science:
- Neuroscience
- Motor Control
- Developmental Pediatrics
Background:
- Children with hemiplegic cerebral palsy (CP) exhibit impaired bimanual coordination during functional tasks.
- Previous research indicated time constraints can improve bimanual coordination in this population.
- The impact of accuracy constraints on bimanual coordination in children with CP remains unclear.
Purpose of the Study:
- To investigate the effect of varying accuracy constraints on upper extremity coordination in children with hemiplegic CP.
- To compare the performance of children with hemiplegic CP to typically developing children under different accuracy demands.
- To understand how task accuracy influences bimanual coordination during a drawer-opening and light-switch activation task.
Main Methods:
- Eleven children with hemiplegic CP and eleven typically developing children performed a task involving reaching, opening a drawer, and activating a light switch.
- Accuracy constraints were manipulated using different handle and switch sizes.
- Movement completion time and coordination patterns were analyzed.
Main Results:
- Increased accuracy constraints prolonged movement completion time for both groups.
- Children with hemiplegic CP showed less sequential movement with higher accuracy constraints (smaller knob).
- Simultaneous high accuracy constraints (handle and switch) negatively impacted performance for children with CP.
Conclusions:
- Task accuracy constraints significantly influence bimanual coordination in children with hemiplegic CP.
- Performance is not always linearly related to task constraints; "more is not better".
- Understanding these influences is crucial for designing effective interventions for children with CP.
Abstract:
Previously we found that children with hemiplegic cerebral palsy (CP) have impaired bimanual coordination compared to typically developing children during a functional drawer-opening task. However, performance of the task under time constraints (fast-as-possible) facilitated better bimanual coordination for these children. Accuracy is another important task constraint that could influence the coordination of the two hands during such tasks. The effect of accuracy constraints on bimanual coordination in children with hemiplegic CP is not well understood. In the present study, children were asked to reach forward and open a drawer with one hand and then activate a light switch inside the drawer with the contralateral hand. Task accuracy constraints (different handles and switch sizes) were manipulated in order to determine their effect on upper extremity coordination. Eleven children with hemiplegic CP (age 8-16 years) and eleven age-matched typically developing children participated in this study. The results show that higher accuracy constraints prolong the total movement completion time for both groups of children. However, children with hemiplegic CP demonstrated less sequential movement with a higher accuracy constraint (a smaller knob handle) than a lower accuracy constraint (a larger loop handle). Nevertheless, presentation of both higher accuracy constraints (handle and switch) at the same time was detrimental to their performance. These influences of task constraints were similar regardless of which hand was used to open the drawer. The results suggest that performance may not be linearly related to the constraints, and in some cases "more is not better".
