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Updated: Jul 31, 2026
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Investigating the Deployment of Visual Attention Before Accurate and Averaging Saccades via Eye Tracking and Assessment of Visual Sensitivity
Published on: March 18, 2019
Progression in neuronal processing for saccadic eye movements from parietal cortex area lip to superior colliculus
1Laboratory of Sensorimotor Research, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892, USApare@biomed.queensu.ca.
Journal of Neurophysiology
|June 2, 2001
Summary
Neurons in the lateral intraparietal area (LIP) and superior colliculus (SC) process saccadic eye movements. Research shows SC neurons are more involved in planning saccades than LIP neurons, suggesting a progressive processing evolution.
Area of Science:
- Neuroscience
- Oculomotor control
- Systems neuroscience
Background:
- Neurons in the lateral intraparietal area (LIP) and superior colliculus (SC) activate before saccadic eye movements.
- The precise progression of covert saccade processing from LIP to SC remains unclear.
Purpose of the Study:
- To compare the discharge properties of LIP output neurons and SC neurons.
- To determine if saccade processing progresses from LIP to SC.
Main Methods:
- Systematic comparison of LIP and SC neuron discharge properties in monkeys.
- Utilized delayed saccade, memory vs. visual trials, and GO/NOGO tasks.
- Identified LIP output neurons via antidromic activation.
Main Results:
- LIP and SC neurons showed overlapping visual and delay period responses.
- SC neurons exhibited stronger saccade-related activity than LIP neurons.
- LIP activity depended on sustained visual stimuli, while SC activity did not.
- SC neurons showed a tighter relationship to impending saccade production than LIP neurons.
Conclusions:
- SC neurons demonstrate greater independence from visual stimuli and a stronger link to saccade production compared to LIP neurons.
- Findings suggest a progressive evolution of saccade processing from LIP to SC, rather than a simple transmission.
- This indicates a sequential refinement of saccade planning across these brain areas.
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