Do pupils dilate when your eyes are closed?

Yes - pupils dilate behind closed eyelids and constrict when eyelids are open, dilating more in the dark as well. Pupils can also dilate behind the eyelids in response to being threatened or scared - the "fight and flight" response of the sympath... read more

Each induces a slight, irrepressible expansion of the pupils in our eyes. For more than a century scientists have known that our eyes' pupils respond to more than changes in light. They also betray mental and emotional commotion. read more

Dilating the pupils of the eyes helps an ophthalmologist view the internal structures, including the lens, optic nerve, blood vessels, and retina. Dilation involves the use of special eye drops that either stimulate contraction of the muscles surrounding the pupil and relaxes the muscles so that they open. read more