What is the true cause of Trichotillomania aslo known as severe obsessive compulsive hair pulling?

The actual cause of Trichotillomania is unknown. It is suspected to be caused by a combination of genetic, biological and environmental factors. Some genetic studies have found a link with obsessive compulsive disorder (OCD) and related disorders, suggesting a possible genetic basis. Brain imaging studies have shown differences in some areas of the brain, particularly in the areas responsible for controlling impulses, reward, and emotion. Environmental factors that may contribute include stressful life events, emotional trauma, and childhood experiences.