Factorial variation of saccade vigor with dual decision processes

Area of Science:

• Neuroscience
• Cognitive Science
• Computational Neuroscience

Background:

• Traditional decision-making models assume independent decision and action processes.
• Limb movement studies reveal evidence quality impacts movement dynamics.
• The relationship between evidence quality and eye movement control remains underexplored.

Purpose of the Study:

• To investigate if saccade velocity is modulated by evidence quality in a visual search task.
• To determine how stimulus-response cue discriminability and singleton localizability affect saccade dynamics.
• To explore individual differences in decision-making strategies based on error patterns and saccade velocity.

Main Methods:

• Monkeys performed a visual search GO/NOGO task with manipulated cue elongation and color similarity.
• Factorial manipulation of stimulus-response cue discrimination and singleton localization efficiency.
• Analysis of response times, error rates, and saccade velocity in relation to task parameters.

Main Results:

• Saccade velocity was higher on correct trials and inversely proportional to response time.
• Both stimulus-response cue discriminability and singleton localizability independently affected saccade velocity.
• Distinct patterns in error rates and saccade velocity suggested varied decision-making strategies across individuals.
• Error response times were influenced by localization and response selection errors.

Conclusions:

• Saccade vigor is influenced by the evidence processing and endpoint selection stages of decision-making.
• Incorporating saccade dynamics provides crucial constraints for biologically plausible computational models.
• This research addresses the challenge of model mimicry in decision-making research.