Your pupils reveal how light shapes sleep—and why age and sex matter

NCT ID NCT05829044

First seen Jul 13, 2026 · Last updated Jul 14, 2026 · Updated 1 time

Summary

This study investigates how the pupil's response to different light stimuli varies by sex and age in healthy people, and how that relates to sleep timing, body clock rhythms, and hormone responses. Participants wear a light-activity monitor for a week, then stay in a research room for 3 days and 2 nights for testing. The goal is to better understand non-visual light input that affects sleep and circadian rhythms.

What this could mean

Our plain-language read of the trial. This is informational only — not medical advice or a prediction.

What this could lead to
If successful, this research could help tailor lighting environments to improve sleep and circadian health for different age and sex groups.
What could go wrong
This is a small observational study (48 participants) focused on healthy volunteers, so findings may not apply to people with sleep disorders or medical conditions.

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As listed by the trial registrant

The condition terms exactly as the trial's registrant entered them.

Contacts and locations

Study contacts

  • Contact

    Phone: •••-•••-•••• Email: •••••@•••••

Locations

  • Massachusetts General Hospital

    RECRUITING

    Boston, Massachusetts, 02114, United States

    Contact Phone: •••-•••-•••• Email: •••••@•••••

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