Dermatophagia – extreme nail biting / biting of skin to point of an obsessive<unk>  disorder (OCD) or other condition leading to self mutilating behaviour such as autistic spectrum disorders (as is the case in this example) or Lesch-Nyhan Syndrome.<unk>  is defined as performing an action persistently and repetitively without it necessarily leading to an actual reward or pleasure.<unk> s could be an attempt to make obsessions go away. The act is usually a small, restricted and repetitive behavior, yet not disturbing in a pathological way.<unk> s are a need to reduce apprehension caused by internal feelings' a person wants to abstain from or control. A major cause of the<unk> s is said to be obsessive–compulsive disorder (OCD). "The main idea of<unk>  is that the likely excessive activity is not connected to the purpose to which it appears directed." Furthermore, there are many different types of<unk> s including shopping, hoarding, eating, gambling, trichotillomania and picking skin, itching, checking, counting, washing, sex, and more. Also, there are cultural examples of<unk> .
Compulsive behavior
Compulsive talking
Musical anhedonia
Musical hallucinations
Body-focused repetitive behavior
Social-emotional agnosia
Passive-aggressive behavior
Compulsive hoarding