Related Experiment Video
Updated: Jul 31, 2025
06:46
Investigating the Deployment of Visual Attention Before Accurate and Averaging Saccades via Eye Tracking and Assessment of Visual Sensitivity
Published on: March 18, 2019
7.1K
Microsaccades are directed toward the midpoint between targets in a variably cued attention task
Shawn M Willett1, J Patrick Mayo1,2
1Department of Ophthalmology, Center for the Neural Basis of Cognition, University of Pittsburgh, 15213 Pittsburgh, PA.
Summary
Microsaccades, small eye movements, may not reliably indicate spatial attention in complex environments. Their direction was not correlated with attention accuracy in monkeys, suggesting caution in using them as biomarkers.
Area of Science:
- Neuroscience
- Ophthalmology
- Cognitive Science
Background:
- Noninvasive biomarkers are crucial for neurological diagnoses.
- Microsaccades, small fixational eye movements, are proposed biomarkers for attention.
- Previous studies linked microsaccade direction to attention using clear cues.
Purpose of the Study:
- To investigate if microsaccade direction reflects visual-spatial attention under variable conditions.
- To assess the robustness of microsaccades as biomarkers in complex, unpredictable environments.
- To analyze microsaccade behavior in monkeys performing a change detection task with varying cue validity.
Main Methods:
- Monkeys performed a change detection task with two stimulus locations and variable cue validities.
- Tens of thousands of microsaccades were analyzed.
- Microsaccade directions were compared between cued locations and between successful/unsuccessful trials.
Main Results:
- Monkeys performed well, adjusting attention based on cue reliability.
- No significant difference in microsaccade direction was found between cued locations with high cue variability.
- Microsaccades were directed towards the midpoint between targets, not individual targets, irrespective of performance accuracy.
Conclusions:
- Microsaccade direction may not be a reliable indicator of covert spatial attention in complex viewing conditions.
- The utility of microsaccades as biomarkers for attention requires careful interpretation, especially outside controlled experimental settings.
- Future research should consider the limitations of microsaccade directionality in naturalistic or complex behavioral contexts.
