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PupilEXT: Flexible Open-Source Platform for High-Resolution Pupillometry in Vision Research
Babak Zandi1, Moritz Lode1, Alexander Herzog1
1Laboratory of Lighting Technology, Department of Electrical Engineering and Information Technology, Technical University of Darmstadt, Darmstadt, Germany.
Frontiers in Neuroscience
|July 5, 2021
Summary
This study introduces PupilEXT, an open-source pupillometry platform for precise pupil measurement. It offers professional-grade remote eye-tracking software and hardware, making cognitive research more accessible.
Area of Science:
- Neuroscience
- Ophthalmology
- Biomedical Engineering
Background:
- The human pupil's response is a key biomarker for cognitive processes, driven by intrinsically photosensitive retinal ganglion cells.
- Accurate measurement of subtle pupil diameter changes (10-2 mm) is crucial for detecting neurocognitive effects.
- Existing commercial pupillometry systems are expensive and use proprietary software, limiting research accessibility and algorithm transparency.
Purpose of the Study:
- To develop an open-source, cost-effective pupillometry platform for professional remote pupil measurement in laboratory settings.
- To provide a user-friendly, cross-platform software solution (PupilEXT) for pupil response research.
- To integrate and evaluate state-of-the-art open-source pupil detection algorithms.
Main Methods:
- Development of an integrated hardware and software pupillometry platform, PupilEXT, compatible with macOS, Windows, and Linux.
- Implementation of six advanced open-source pupil detection algorithms: Starburst, Swirski, ExCuSe, ElSe, PuRe, and PuReST.
- Creation of a 120-fps demo system for calibration and accuracy assessment in stereo mode.
Main Results:
- The developed system achieved a calibration accuracy of 0.003 mm and an average temporal pupil measurement detection accuracy of 0.0059 mm in stereo mode.
- PupilEXT software offers comprehensive features including advanced pupil detection, measurement validation, data acquisition, and stereo vision capabilities.
- The platform is system-independent and provides a user-friendly graphical interface for professional pupil response research.
Conclusions:
- The open-source PupilEXT platform provides a professional, accessible, and accurate alternative to high-cost commercial pupillometry systems.
- This accessible tool democratizes advanced pupil measurement for cognitive neuroscience and related research fields.
- The platform's open-source nature fosters transparency and further development in pupillometry algorithms and applications.
