English: A human eye after the pupil was dilated using drops during an eye exam. Self-portrait by Ben Schumin. (Photo credit: Wikipedia ) The dilation and constriction of the pupils reveals how hard we're thinking. It has been said that the eyes are windows to the soul. Research has at least shown that the apertures of our eyes offer a glimpse into the mind. Furthermore, the pupil will dilate if a person sees an object of interest. Dilated eyes may be a sign of a head injury or another serious health condition. This condition is called mydriasis. How Long Do Pupils Stay Dilated After an Eye Exam? Dilated eyes may be a sign of a head injury or another serious health condition. Eye dilation is part of a comprehensive eye exam. Is it necessary to have my eyes dilated during every eye exam? Related articles Eye-Opener: Why Do Pupils Dilate in Response to Emotional States? Pupil Dilation Co-Varies with Memory Strength of Individual Traces in a Delayed Response Paired-Associate