According to "Culture and Human Behavior: Culture-Bound Syndromes," the Japanese

According to "Culture and Human Behavior: Culture-Bound Syndromes," the Japanese culture-specific disorder hikkomori:

A) is very common, affecting an estimated 10 million or more people.
B) is characterized by extreme social anxiety because of fear that one's appearance, smell, facial expression, or body language will offend, insult, or embarrass other people.
C) has symptoms in common with several Eastern disorders, including ataque de nervios, taijin kyofusho, and hypochondriasis.
D) is characterized by extreme social withdrawal, a preoccupation with video games and Internet surfing, an inability to work or attend school, and virtually no social interactions with family members or the outside world.