OCD is not a brain disorder but an abnormal secretion and disturbance of the balance of various neurotransmitters, mainly 5-hydroxytryptamine. In particular, if the secretion of 5-hydroxytryptamine increases abnormally and the balance with other neurotransmitters such as dopamine is disturbed, there will be a lot of compulsive thinking or compulsive behavior. OCD can also be caused by genetics or personality. For example, if a family member has schizophrenia, depression or OCD, the probability of OCD is several times higher than that of an ordinary person. Also, if someone is timid, cautious, and particularly strong, and has many perfectionist tendencies, the likelihood of suffering from OCD is greatly increased. From these analyses, it is clear that OCD is not a bad brain but a psychosomatic disorder.