A new study reveals that pupil size fluctuates constantly during sleep, reflecting changes in brain activation levels.

Scientists have long studied the size of our pupils to understand attention, emotion and even medical conditions. But now, new research has surprisingly revealed that they change size in sync with our ...

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 ...

The difference in pupil size between inhalation and exhalation was large enough to theoretically affect vision. The study also showed that the function is intact in people born without the ...

The pupil responds to light, which is essential for our vision and how we see our surroundings. Three known mechanisms change ...

Indeed, this reflex is so reliable that doctors use it to assess brain function. If a pupil fails to react to light, it could signal a medical emergency such as a stroke. However, it is not just ...

IN the past many investigations have been carried out on the static and dynamic reactions of the human pupil to illumination of the eye using white light. In this respect it seems surprising that ...

Structure Coloured part of the eye that contains muscles. These relax or contract to adjust the size of the pupil. Function Controls how much light enters the pupil. Structure Transparent ...

The difference in pupil size between inhalation and exhalation was large enough to theoretically affect vision. The study also showed that the function is intact in people born without the ...