Related Experiment Video
Updated: Sep 26, 2025

Comparison of Three Clinical Stereoscopic Methods for Measuring Binocular Visual Function During Amblyopic Treatment in Unilateral Amblyopia
Published on: September 27, 2024
Evaluating visuomotor coordination in children with amblyopia
Sabrina W Hou1, Yan Zhang1, Lisa Christian2
1Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada.
Insights
Children with abnormal binocular vision, including amblyopia (lazy eye) and strabismus, exhibit visuomotor deficits in complex tasks. Reduced stereoacuity, not visual acuity, correlated with the severity of these movement sequencing challenges.
Area of Science:
- Ophthalmology
- Developmental Neuroscience
- Motor Control
Background:
- Previous studies identified reaching and grasping deficits in adults with amblyopia and poor stereoacuity.
- Visuomotor deficits in children, particularly in complex sequential movements, remain less understood.
Purpose of the Study:
- To compare visuomotor performance in children with abnormal binocular vision (amblyopia/strabismus) versus typically developing children.
- To investigate age-related differences and the impact of stereoacuity and visual acuity on visuomotor deficits in children.
Main Methods:
- Assessed visual acuity, stereoacuity, and hand-movement kinematics during a bead-threading task.
- Compared 21 children with abnormal binocular vision to 236 typically developing children (ages 5-14).
- Analyzed kinematic data, including grasp, thread, and total movement durations, across immature (5-9 years) and mature (10-14 years) age groups.
Main Results:
- Children with abnormal binocular vision demonstrated significantly longer grasp, thread, and total movement durations.
- Grasp duration was consistently longer in both immature and mature patient groups.
- Thread and total movement durations were prolonged in the mature patient group, with grasp duration being the most affected kinematic parameter.
- Reduced stereoacuity, rather than reduced visual acuity, was linked to more severe visuomotor deficits.
Conclusions:
- Children with amblyopia and/or strabismus experience significant visuomotor challenges, especially in tasks requiring sequential movements.
- Grasp execution is the primary kinematic parameter affected, irrespective of age.
- Stereoacuity loss is a stronger predictor of visuomotor deficit severity than visual acuity loss in this pediatric population.
Abstract:
Past research has reported deficits on reaching and grasping tasks in adults with amblyopia and degraded stereoacuity, but less is known about visuomotor deficits in children-specifically, for complex tasks that require movement sequencing. This study therefore compared the visuomotor performance in 21 children with abnormal binocular vision (patient group) due to amblyopia and/or strabismus to that of 236 children with normal binocular vision development (control group) ages 5-14 years. Visual acuity, stereoacuity, and hand-movement kinematics on a bead-threading task were assessed. The patient group showed significantly longer durations than the control group on grasp, thread, and total movement durations. Both groups of participants were then split into immature (ages 5-9 years) and mature (ages 10-14 years) groups based on the maturation age for these parameters in control children. Grasp duration was longer in both mature and immature patient groups; thread and total movement durations were longer in the mature patient group only. Grasp duration was the most disrupted kinematic parameter in children with disrupted binocular vision due to amblyopia and/or strabismus, regardless of age. The level of stereoacuity loss rather than the depth of visual acuity loss was associated with the severity of visuomotor deficits.

