Being too otaku is also a disease. In an article published in the February issue of the American Journal of Psychiatry, researchers report a case of a 39-year-old hikikomori: a middle-aged Japanese male who barely left his house for 19 years and eventually achieved some improvement through psychotherapy. The case, “Mr. T,” is a Japanese 39-year-old unemployed man who lives with his parents. For most of the past 19 years, Mr. T has not left his room; he has not worked and his attitude toward life is to “take his time”. His main pastimes are playing games and shopping online; a few years ago, his online shopping habits left him with tens of thousands of dollars in debt. Mr. T’s mother, a homemaker, cooks for Mr. T every day. As a wealthy third-generation man, Mr. T received a steady stream of financial support from his wealthy grandfather to support his lifestyle; in recent years, his “bankbook” has been his father’s retirement fund. Asked why he rarely goes out, Mr. T. explained mainly that he doesn’t want to be seen by others, especially given his lack of success. Although his frequency of travel varied over the years, in general he only left the house once a month, when he went to the clinic, and Mr. T’s circadian rhythm was reversed: he generally did not sleep during the day, except on those days when he went to the clinic. Mr. T’s mother had no significant abnormalities prior to the birth of Mr. T; she recalled that Mr. T had no developmental problems during childhood. Temperamentally, Mr. T was shy and avoided engaging in activities that might lead to his being noticed by others. Growing up, Mr. T actually had some friends, but by the time he reached secondary school, his interaction with these friends had decreased due to increasing concern about being seen by others in public. During his compulsory education, Mr. T’s academic performance was always in the middle; after secondary school, Mr. T completed a vocational training program to become certified as a health care technician. However, he lacked the motivation to find a job and it was at this point that he began to live in deep isolation. A year later, at the age of 21, Mr. T was taken by his mother to a community psychiatrist, who was a specialist in psychosomatic medicine, with a complaint of “pain when stretching his neck in public”. The physical examination did not reveal any organic abnormalities, and Mr. T was then treated with regular psychological counseling and medication. This condition continued for 3 years, and due to the lack of significant improvement, Mr. T switched to a psychiatrist at the request of his mother, who suspected that Mr. T was in the prodromal phase of psychosis and began treatment with atypical antipsychotics. Despite a full course of three medications, Mr. T’s condition did not improve significantly. At the age of 28, one of Mr. T’s sisters had health problems and Mr. T’s mother began to spend more energy on her, which led to a sudden onset of somatic aggression against his mother. At that time, Mr. T was involuntarily admitted to a university hospital. A psychiatric examination at that time revealed that Mr. T was in an agitated state, but no significant hallucinatory delusions were detected. His medications included haloperidol and valproic acid, which were designed to improve his agitation and irritability. Mr. T’s participation in ward activities and group therapy was also low. However, after 4 months, Mr. T was discharged with a diagnosis of Taijin Kyofusho (“transphobia,” an interpersonal fear of offending others) and a suspected diagnosis of diffuse developmental disorder, although Mr. T’s symptoms were not sufficient to make a diagnosis. However, Mr. T’s symptoms were not sufficient for a diagnosis. After being discharged from the hospital, Mr. T was seen by a new psychiatrist who suspected hikikomori (引き笼もり, hikikomori), a persistent and severe form of social withdrawal, and Mr. T and his mother began family therapy, aimed at improving his underlying family dynamics, once every two weeks. Through therapy, Mr. T finally became capable of expressing his amae (甘え) – a dependence on his mother and a desire for her care; these feelings were transformed into jealousy and anger when the patient’s sister began to take away her mother’s care. Mr. T also received behavioral therapy with an exposure response/ritual blocking (EX/RP) Mr. T also received behavioral therapy with an exposure response/ritual blocking (EX/RP) component, and his fear of being seen by others gradually decreased until he was able to complete occasional shopping tasks. When Mr. T’s father retired, he also became involved in family therapy. Overall, Mr. T’s family’s family functioning improved, as did Mr. T’s problems with reckless shopping. Recognizing that his parents are aging at an accelerated rate and that he needs to take on more adult responsibilities, Mr. T is currently learning how to take care of himself after his parents’ death. Discussion Although extreme social isolation is deeply rooted in Japanese culture, the issue of social withdrawal has only been discussed in Japanese psychiatry since the 1970s, and the term hikikomori only emerged in the 1990s. In the DSM-5, hikikomori is both an idiom with painful connotations and a cultural syndrome. In the former case, the term has become a household word in Japan, entered the English dictionary, and attracted media attention, resulting in people with similar conditions worldwide calling themselves “hikikomori”; in the latter case, at an operational level, we have defined hikikomori as spending most of the day, and almost every day, at home. The patient stays at home, avoids social situations and relationships, and has significant pain or functional impairment associated with it for at least 6 months. The lifetime prevalence of hikikomori among young Japanese is approximately 1.2%, and it usually starts in adolescence or early adulthood and takes an average of 4 years to develop to clinical significance. Idiopathic hikikomori can also be seen clinically, but co-morbidities with other psychiatric disorders, including avoidant personality disorder, major depressive disorder, and social anxiety disorder, are more common in cases such as Mr. T’s. In the United States, clinical presentations such as Mr. T’s, including sometimes aggressive behavior toward others, may have led to a diagnosis of schizophrenia. aberrant family dynamics were a key feature in Mr. T’s case, including the son’s overdependence on his mother and the largely absent role of the father. In social and economic terms, hibernation is important because individuals are usually dependent on others (usually parents) for food, shelter, and clothing long into adulthood, so Mr. T’s case could be called an “adultolescent. The conceptual model proposed in a recent systematic review also suggests that dysfunctional parenting and family dysfunction are key factors in the development of hikikomori. Mr. T responded partially to treatment, in large part through psychotherapy; psychotherapy is relatively popular in Japan. Observational studies have shown that treatment outcomes for hikikomori are generally suboptimal. Despite the lack of evidence-based treatment, hikikomori has generated a high level of public interest and a wide range of clinical resources within Japan. Since 2000, nationwide hikikomori support centers have emerged in Japan, often providing telephone counseling, psychiatric counseling involving families and individuals, and employment resources. Extended and critically evaluated public health strategies are key to improving the prognosis of hikikomori. Researchers are also exploring whether shortening the length of social withdrawal criterion to 3 months would help in the early detection of hikikomori.