Q: My elderly cat’s pupils seem to stay dilated, even in bright light. Why? A: In old cats, dilated pupils are often just a sign of a harmless condition called iris atrophy. However, if your cat has ...

Medically reviewed by Andrew Greenberg, MD Key Takeaways Pupils naturally dilate in low light to allow more light into the ...

Normally, a person's pupils naturally widen (or dilate) in low-light environments to allow more light into the eye. However, in a new study, researchers reported that a person's pupils also dilate ...

The iris is a structure behind the transparent cornea of the eye. It has a circular opening called the pupil that changes size in response to the light level. Your pupils are usually the same size as ...

Eye dilation usually lasts four to six hours, but it can last longer depending on various factors. Light-colored eyes may stay dilated longer after an exam. After an eye exam, you may receive special ...

Last month, I attended a conference for physicians presented by Dr. Jesse Berry, an associate professor of ophthalmology at USC and the director of the Ocular Oncology and the Retinoblastoma Programs ...

Working memory is one of the brain’s executive functions, a skill that allows humans to process information without losing track of what they’re doing. In the short term, working memory allows the ...