Science & Nature · 2
What is the name of the response where your pupils dilate in low light?
Answer
Pupil reflex
The pupil reflex, or pupillary light reflex, is an automatic neurological response where the pupil (the opening in the iris) dilates in low light and constricts in bright light. This reflex is controlled by the autonomic nervous system and involves photoreceptors in the retina sending signals through the optic nerve to the brain stem, which controls the iris muscles. The pupil's rapid response helps regulate the amount of light entering the eye to maintain sharp vision and protect the retina from light damage. This reflex occurs involuntarily and is one of the cranial nerve reflexes tested during medical examinations.
💡 Did you know?
Your pupils can change size within milliseconds, allowing you to maintain clear vision across a billion-fold range of light intensities.
Other options people guess
- Accommodation
- Convergence
- Lens refraction
Topics
- anatomy
- vision
- neurology
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