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Related Experiment Video

Updated: Feb 5, 2026

Pupillary Response as Assessment of Effective Seizure Induction by Electroconvulsive Therapy

Pupillary Response as Assessment of Effective Seizure Induction by Electroconvulsive Therapy

Published on: April 11, 2019

A Custom-made Pupillometer System for Characterizing Pupillary Light Response.

Nefati Kıylıoğlu¹, Mahmut Alp Kılıç¹, Tolga Kocatürk²

¹Adnan Menderes University Faculty of Medicine, Department of Neurology, Division of Clinical Neurophysiology, Aydın, Turkey.

Turkish Journal of Ophthalmology

|September 12, 2018

Summary

A new pupillometer system using a modified web camera accurately measures pupil size and light response. This low-cost system shows good repeatability, offering potential for various physiological and psychological studies.

Keywords:

Pupillary light reflex pupillary response pupillometer

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Area of Science:

Biomedical Engineering
Ophthalmology
Neuroscience

Background:

Pupillometry is crucial for assessing autonomic nervous system function and cognitive states.
Existing pupillometer systems can be expensive and complex.

Purpose of the Study:

To design and construct a cost-effective and viable pupillometer system.
To validate the system's accuracy and reliability in measuring pupillary light response.

Main Methods:

A modified web camera with infrared filter removed was used.
Infrared and visible LEDs provided controlled light stimuli.
Pupil size was recorded at 30 fps and analyzed offline with custom software.

Main Results:

Accurate pupil size measurements were achieved when reflections were excluded.
The system demonstrated moderate to excellent repeatability (86.8-87.8%).
The results confirm the system's reliability for pupillometry.

Conclusions:

The developed pupillometer system provides quantitative data on pupillary light response.
Further development could establish it as a low-cost alternative for diverse research applications.
Potential applications include studies on cognitive function, drug effects, and sleep disorders.