According to the BBC, slit pupils are a sign of having "multifocal" lenses. Amongst other things, multifocal lenses allow animals to focus on different colors. Why would this be important to cats?

There are many different types of medications that can interfere with the nerves that make your pupils dilate, including: 3. Recreational drug use Recreational drugs also affect your nervous ...

Drug use: Various drugs produce different effects on pupil diameter—stimulants such as cocaine and amphetamines tend to dilate, whereas opioids such as heroin tend to constrict. Neurological ...

Visual illusions of motion are a major source of interest in the vision research community. Explaining how a still image can produce an illusory perception of motion is important for a more ...