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Are Left- and Right-Eye Pupil Sizes Always Equal?
Nergiz Ercil Cagiltay1, Gonca Gokce Menekse Dalveren
1Atilim University, Faculty of Engineering, Department of Software Engineering, Ankara, Turkey.
Journal of Eye Movement Research
|April 8, 2021
Summary
Right-handed surgical residents showed larger right-eye pupil sizes than left-eye pupil sizes during simulated surgery using their right or both hands. No significant difference was observed when using only the left hand, offering insights into cognitive load.
Area of Science:
- Ophthalmology
- Cognitive Science
- Surgical Education
Background:
- Eye movements and pupil size are critical indicators of cognitive load and human behavior.
- Previous research assumes equal left and right pupil sizes, often averaging them or using a single eye.
- This assumption may overlook subtle, yet significant, differences in pupillary responses.
Purpose of the Study:
- To investigate potential differences between left and right eye pupil sizes in right-handed surgical residents.
- To analyze these differences during simulated surgical tasks under varying hand conditions (left, right, both).
- To explore the implications for understanding cognitive load in surgical training.
Main Methods:
- Utilized a computer-based simulation environment for surgical tasks.
- Monitored and compared left and right eye pupil sizes of participants.
- Examined pupil size variations across three conditions: left-hand, right-hand, and both-hands task performance.
Main Results:
- Right-eye pupil sizes were frequently larger than left-eye pupil sizes during right-hand and both-hands surgical simulations.
- No statistically significant difference in pupil size between the left and right eyes was found during left-hand-only tasks.
- These findings suggest asymmetric pupillary responses related to task demands and hand dominance.
Conclusions:
- Asymmetric pupil sizes (right > left) may reflect differential cognitive load during specific surgical tasks in right-handed residents.
- The findings challenge the assumption of equal pupil sizes and advocate for analyzing each eye separately.
- Further research should explore task difficulty, skill level, and handedness effects on asymmetric pupil responses for enhanced surgical training insights.
