Phobias are a common form of anxiety disorders. An American study by the National Institute of Mental Health (NIMH) found that between 8.7% and 18.1% of Americans suffer from phobias. Broken down by age and gender, the study found that phobias were the most common mental illness among women in all age groups and the second most common illness among men older than 25.
Phobias are not generally diagnosed if they are not particularly distressing to the patient and if they are not frequently encountered. If a phobia is defined as “impairing to the individual”, then it will be treated after being measured in context by the degree of severity. A large percent of the American population is afraid of public speaking, which could range from mild uncomfortability, to an intense anxiety that inhibits all social involvement.
Phobias are generally caused by an event recorded by the amygdala and hippocampus and labeled as deadly or dangerous; thus whenever a specific situation is approached again the body reacts as if the event were happening repeatedly afterward. Treatment comes in some way or another as a replacing of the memory and reaction to the previous event perceived as deadly with something more realistic and based more rationally. In reality most phobias are irrational, in that the subconscious association causes far more fear than is warranted based on the actual danger of the stimulus; a person with a phobia of water may admit that their physiological arousal is irrational and over-reactive, but this alone does not cure the phobia.