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 ...

His gaze softens as he draws closer to you. With one hand around your waist and the other cradling your jaw, he pulls you in. You look into his eyes, and notice his pupils have grown large and hungry.

A function of the body that happens automatically without a thought, was considered to be impossible to replicate at will. Yet a 23-year-old student in Germany can shrink and enlarge his pupils on ...