Saccade metrics reflect decision-making dynamics during urgent choices

Area of Science:

• Cognitive Neuroscience
• Oculomotor Research
• Perceptual Decision Making

Background:

• Perceptual judgments are traditionally analyzed using psychometric and chronometric functions.
• These functions map accuracy and reaction time to sensory stimulus features.
• The dynamics of perceptual evaluation during decision-making remain incompletely understood.

Purpose of the Study:

• To investigate if saccade metrics, beyond standard performance measures, reflect perceptual evaluation dynamics.
• To explore the relationship between saccade kinematics and decision confidence in an urgent-choice task.
• To determine if a unified model can explain both behavioral and neural aspects of perceptual decision-making.

Main Methods:

• Recorded various saccade metrics (e.g., peak velocity) during an urgent-decision task.
• Mapped saccade metrics as a function of sensory cue viewing time.
• Utilized a race-to-threshold model to explain observed data and neuronal activity.

Main Results:

• Saccade metrics, including peak velocity, were modulated by sensory cue viewing time, mirroring psychometric functions.
• Saccade peak velocity significantly correlated with statistical decision confidence.
• The race-to-threshold model successfully replicated standard performance measures and cortical oculomotor neuronal activity.

Conclusions:

• Saccade metrics provide novel insights into the temporal dynamics of perceptual evaluation.
• Saccade kinematics, particularly peak velocity, serve as reliable indicators of cognitive certainty during decision-making.
• The findings suggest that stereotyped saccade metrics encode subtle but significant traces of underlying cognitive processes.