Pupil Response in Visual Tracking Tasks: The Impacts of Task Load, Familiarity, and Gaze Position

Area of Science:

• Cognitive Science
• Human-Computer Interaction
• Neuroscience

Background:

• Pupil size is a crucial biosignal for monitoring human behavior and cognitive states.
• Understanding pupil response dynamics is key to interpreting cognitive load and learning processes.

Purpose of the Study:

• To investigate how task load, task familiarity, and gaze position influence pupil size during a visual tracking task.
• To explore the relationship between pupil size and cognitive load, particularly in a learning context.

Main Methods:

• Fifteen participants performed an arrow tracking learning task with varying task loads.
• Pupil size data were collected using a Tobii Pro Nano eye tracker.
• Statistical analysis included a three-way ANOVA and a linear mixed-effect model for cognitive load assessment (NASA-TLX).

Main Results:

• Task repetition led to reduced pupil size, an effect that lessened with increased task load.
• The relationship between pupil size and cognitive load exhibited an inverted U-shaped curve.
• No significant differences in pupil size were observed across different gaze positions.

Conclusions:

• Pupil size dynamically changes with task load, familiarity, and gaze scanning patterns during learning.
• Findings offer sensory evidence for improving educational strategies by considering pupil response metrics.
• The inverted U-curve relationship highlights the complex interplay between cognitive load and pupil dilation.