In these experiments, however, Van Gelder, and his research team demonstrated that the constriction of the pupil in the chick eye seems to be regulated by cryptochrome rather than melanopsin, ...

Movie demonstrating the increase in accommodative eye vergence and pupil constriction when the fixating eye (left side of image, right eye of subject) is exposed to -5D defocus. The occluded eye ...

People often mimic each other's facial expressions or postures without even knowing it, but new research shows that they also mimic the size of each other's pupils, which can lead to increased trust.

A study has found that people appear more attractive when their pupils are constricted, making their coloured irises seem bigger and brighter. New research by Zachary Estes, Professor of Marketing at ...

New pupillometry research reveals how post-traumatic stress disorder (PTSD) may affect both branches of the autonomic nervous system. By measuring how someone's pupils dilate and constrict in response ...

A domestic cat’s eye narrows to a razor-thin vertical slit in bright sunlight, while a grazing sheep stares out through a wide horizontal bar. These are not cosmetic quirks. A 2015 study in Science ...