Contribution of binocular vision to the performance of a precision manipulation task in 8-14 years old children

Abstract

Purpose : Previous research has established that prehension performance is less efficient in adults and children with abnormal binocular vision; however, relatively little is known about the association between the maturation trajectory of binocular visual function, and the development of visuomotor skills in children with normal binocular vision. Therefore, the goal of this study was to assess the contribution of stereopsis, ocular vergence, and accommodative function, to the performance of a precision manipulation task in elementary school-age children.

Methods : Twenty-three typically developing children (age: 8-14 years, 11 girls) without amblyopia or strabismus were tested. Binocular visual function assessment included tests for stereoacuity, vergence facility, and accommodative facility. The prehension task involved picking up a small bead, and placing it onto a vertical needle while eye and limb movements were recorded with a video-based eyetracker and a motion capture camera. A multiple regression analysis was used to examine the contribution of stereoacuity, vergence, and accommodation to motor performance. Age was included as a covariate in the regression analysis to determine if changes in binocular function provide unique contribution to the model.

Results : Streoacuity and age were significant predictors for total movement time (R²=0.43; p=0.004). Stereoacuity was a stronger predictor explaining 33% of total variance, while age explained 10%. The only significant predictor for grasp duration was stereoacuity, which explained 41% of variance (R²=0.41; p=0.001). In contrast, age was the only significant predictor for placement duration, explaining 49% of total variance (R²=0.49; p<0.001). Binocular function measures did not explain significant variance in other motor performance measures such as peak velocity and reach duration.

Conclusions : Our results indicate that stereoacuity has a significant contribution to the performance of a manipulation task that requires precision grasping in children with normally developing binocular vision. Overall, this study adds to the growing body of research indicating that binocular vision provides critical sensory input for optimal development of fine motor skills.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.