Primate antisaccade. II. Supplementary eye field neuronal activity predicts correct performance

Area of Science:

• Neuroscience
• Ophthalmology
• Cognitive Science

Background:

• The supplementary eye field (SEF) plays a role in voluntary eye movements.
• Antisaccades are voluntary eye movements toward a location opposite a visual stimulus, contrasting with reflexive prosaccades.
• Understanding SEF's role in antisaccade generation is key to comprehending executive control of gaze.

Purpose of the Study:

• To investigate the involvement of the supplementary eye field (SEF) in the production of antisaccades.
• To analyze the activity of SEF neurons during both antisaccade and prosaccade tasks.

Main Methods:

• Neuronal activity was recorded from 3 macaque monkeys performing interleaved antisaccade and prosaccade tasks.
• Analysis focused on visual, eye-movement, and instruction/fixation neurons within the SEF.
• Neuronal firing rates were examined in relation to saccade performance and task conditions.

Main Results:

• 73% of SEF eye-movement-related neurons exhibited significantly higher firing rates before antisaccades compared to prosaccades.
• Single-trial analysis revealed that eye-movement neuron firing rates 40 ms before a saccade predicted successful antisaccade performance.
• Fixation neurons consistently fired more on antisaccade trials during the instruction period, though significance varied.

Conclusions:

• The supplementary eye field (SEF) is critically involved in the generation of antisaccades.
• Specific patterns of SEF neuronal activity differentiate antisaccade from prosaccade execution.
• SEF activity, particularly of eye-movement neurons, is a strong predictor of successful antisaccade performance.