This impulse control disorder causes otherwise mentally sane people to eat and consume parts of themselves by biting and chewing compulsively. Examples have included men who began by chewing their nails and didn’t stop until most of their fingers were mutilated stubs. This rare affliction is not properly classified as a mental illness in manuals used for the diagnosis of mental disorders, however it could be classified vaguely as an impulse control disorder. Autophagia is assumed to be in some way related to spinal cord injuries. Experiments with rats showed that those with damaged spinal cords had a tendency to bite and chew their nails and feet and so scientists pioneered a bitter tasting substance to apply to the affected areas. After a few weeks the behaviour had vastly diminished but it remains to be seen whether such a substance would be used on humans. Sufferers are also often prescribed anti-psychotics and anti-depressants which can be somewhat effective.