Cornell University researchers have found that the pupil is key to understanding how, and when, the brain forms strong, long-lasting memories. By studying mice equipped with brain electrodes and tiny ...

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.

For the first time, researchers have been able to observe how the pupils react during sleep over a period of several hours. A look under the eyelids showed them that more happens in the brain during ...

One evening in 1960, the psychologist Eckhard Hess was at home, flipping through a book of “strikingly beautiful animal photographs.” His wife commented that the light in the room must be dim, because ...

The pupillary light response helps our eyes see the world around us in various lighting conditions ranging from bright, sunny days to dark, moonlit nights. Like a camera's aperture, this adaptive ...