What Is the Function of the Pupil?

By Staff WriterLast Updated Mar 26, 2020 2:23:41 AM ET
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The primary function of the human pupil is to regulate the amount of light that enters the eye. When the pupil is smaller, less light enters the eye in bright environments. The pupil gets larger as light levels decrease to let more light into the eye. Doctors examine the pupil to ascertain one's neurological function.