Abstract
Purpose :
Research has shown that children with abnormal binocular vision due to amblyopia and/or strabismus often perform significantly worse on visuomotor tasks. The degree of deficit appears to be task dependent, however, it has not been established which tasks present the greatest challenge or which aspects of binocular function contribute to visuomotor task performance. Our previous work with normally developing school-age children demonstrated that stereoacuity was associated with the performance of a precision grasping task, while vergence facility was associated with the performance of a precision aiming task. The gaol of the current study was to assess visuomotor performance using the same two tasks in children with abnormal binocular vision.
Methods :
The cohort tested to date includes a control group of 38 typically developing children (age: 8-14 years, 19 girls) without amblyopia or strabismus, and 6 children (age: 8-14 years, 3 girls) with abnormal binocular vision due to amblyopia and/or strabismus. The precision grasping task involved picking up a small bead, and placing it onto a vertical needle. A video-based eyetracker and a motion capture camera were used to record eye and limb movements. The precision aiming task involved using a pen to mark a dot inside a small circle. The number of circles marked correctly in 20 sec was the main outcome variable.
Results :
Children with abnormal binocular vision performed significantly worse on the precision grasping and aiming tasks in comparison to their age and gender matched peers. The most significant deficit was found for the grasping component (p<0.01), where the grasp duration was 140 ms longer in comparison to the control group. The prehension deficit was the greatest in children with negative stereoacuity. Children with abnormal vergence facility also scored significantly lower on the precision aiming task. Specifically, during this test children completed 17 circles in comparison to 29 circles for the control group (p<0.0005).
Conclusions :
Our results indicate that, children with amblyopia and strabismus show significant deficits during the performance of precision grasping and aiming tasks, which adds to the growing body of research indicating that binocular vision provides critical sensory input for optimal development of fine motor skills.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.