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Updated: May 28, 2026
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Assessing Binocular Central Visual Field and Binocular Eye Movements in a Dichoptic Viewing Condition
Published on: July 21, 2020
Neural correlates of the multiple-object tracking deficit in amblyopia
John Secen1, Jody Culham, Cindy Ho
1University of British Columbia, Department of Ophthalmology and Visual Sciences, Room A146, 4480 Oak Street, Vancouver, BC, Canada V6H 3V4. johnsecen@gmail.com
Vision Research
|November 1, 2011
Summary
Multiple-object tracking deficits in amblyopia involve reduced brain activity in motion processing areas. Both passive viewing and active tracking showed differences in the amblyopic brain, impacting visual attention.
Area of Science:
- Neuroscience
- Ophthalmology
- Cognitive Science
Background:
- Amblyopia, or 'lazy eye,' is associated with visual processing deficits.
- Multiple-object tracking (MOT) impairments are documented in amblyopia, affecting both affected and unaffected eyes.
Purpose of the Study:
- To investigate the neural mechanisms underlying MOT deficits in amblyopia using functional magnetic resonance imaging (fMRI).
- To compare brain activation patterns during MOT tasks between individuals with amblyopia and healthy controls.
Main Methods:
- fMRI scans were acquired from amblyopic and control groups during MOT tasks with varying target numbers (1, 2, 4) and passive viewing.
- Activation was analyzed in key visual and attention-related regions: V1, MT+, SPL, FEF, anterior IPS, and posterior IPS.
Main Results:
- Brain regions, excluding V1, showed increased activation with higher attentional load in both groups.
- The middle temporal complex (MT+) exhibited reduced activity in the amblyopic group across all conditions.
- Reduced activation was observed in the anterior intraparietal sulcus (aIPS) and frontal eye fields (FEF) when viewing with the amblyopic eye during high-load tracking.
Conclusions:
- The findings suggest that MOT deficits in amblyopia stem from impairments in both low-level passive and high-level active motion processing systems.
- Neural underactivity in motion-sensitive areas like MT+ and attention networks (aIPS, FEF) contributes to visual tracking difficulties in amblyopia.
