[citation needed] Emotional variables may have a differential impact on the expression of BFRBs.

[citation needed] Researchers are investigating a possible genetic component.

[7] Cognitive behavioral therapy was cited as experimental evidence based therapy to treat trichotillomania and nail biting;[7] a systematic review found best evidence for habit reversal training and decoupling.

[8] Another form of treatment that focuses on mindfulness, stimuli and rewards has proven effective in some people.

[2] These collections of symptoms have been known for a number of years, but only recently have appeared in widespread medical literature.