How light-sensitive eye cells help control pupil size and body clock

Intrinsically photosensitive melanopsin retinal ganglion cells are key players in regulating pupil size and circadian rhythms.

• These cells maintain pupil diameter and are involved in the recovery and post-illumination phases of the pupillary light reflex.
• They serve as the main source of environmental light information for the suprachiasmatic nucleus, which helps regulate circadian rhythms.
• Recent findings enhance understanding of the histology and physiological functions of these ganglion cells.
• A clinical framework is proposed for assessing inner retinal function through the pupillary light reflex, which may help in detecting retinal diseases.

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