Spectral decomposition of pupillary unrest using wavelet entropy

Area of Science:

• Physiology
• Neuroscience
• Ophthalmology

Background:

• Pupil size fluctuations (pupillary unrest) exhibit physiological rhythms linked to respiration and cardiovascular activity.
• The clinical significance of pupillary unrest remains underexplored despite its physiological basis.

Purpose of the Study:

• To investigate the relationship between pupillary unrest and autonomic nervous system (ANS) function.
• To explore the potential of pupillary unrest as a non-invasive biomarker for ANS status.

Main Methods:

• Analysis of pupillograms from 29 healthy participants across various time scales.
• Correlation of pupillary unrest metrics with established cardiovascular and cardiorespiratory autonomic function indices.

Main Results:

• Discovery of distinct respiratory and cardiovascular rhythms within temporal pupil size fluctuations.
• Identification of significant lateralization in pupillary unrest dependencies.
• Demonstration of a correlation between left pupil unrest and vagal heart rate regulation and baroreflex sensitivity.

Conclusions:

• Pupillary unrest reflects autonomic nervous system activity.
• Left pupil fluctuations are particularly significant for assessing autonomic function.
• Pupillometry offers a promising, non-invasive method for evaluating autonomic nervous system status.