Fear of: confined spaces.
Claustrophobia is one of the more well-known phobias — although it's estimated that only 5 to 7 percent of the population suffers from it. Claustrophobics are afraid of suffocating or being trapped in tight, confined spaces, like elevators or closets.
Often, claustrophobia can be treated with cognitive behavioral therapy. The treatment slowly introduces a person to a confined space and teaches him or her to cope with the panic and anxiety head-on.