Hikikomori, also known as severe social withdrawal, is total withdrawal from society and seeking extreme degrees of social isolation and confinement. Hikikomori refers to both the phenomenon in general and the recluses themselves. The concept is primarily recognized only in Japan, although similar concepts exist in other languages and cultures. Hikikomori have been described as loners or "modern-day hermits". Estimates suggest that half a million Japanese youths have become social recluses, as well as more than half a million middle-aged individuals.
Tic disorderTic disorders are defined in the Diagnostic and Statistical Manual of Mental Disorders (DSM) based on type (motor or phonic) and duration of tics (sudden, rapid, nonrhythmic movements). Tic disorders are defined similarly by the World Health Organization (ICD-10 codes). The fifth revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), published in May 2013, classifies Tourette syndrome and tic disorders as motor disorders listed in the neurodevelopmental disorder category.
High-functioning autismHigh-functioning autism (HFA) was historically an autism classification where a person exhibits no intellectual disability, but may exhibit deficits in communication, emotion recognition and expression, and social interaction. HFA has never been included in either the American Psychiatric Association's Diagnostic and Statistical Manual (DSM) or the World Health Organization's International Classification of Diseases (ICD), the two major classification and diagnostic guidelines for psychiatric conditions.
ArousalArousal is the physiological and psychological state of being awoken or of sense organs stimulated to a point of perception. It involves activation of the ascending reticular activating system (ARAS) in the brain, which mediates wakefulness, the autonomic nervous system, and the endocrine system, leading to increased heart rate and blood pressure and a condition of sensory alertness, desire, mobility, and reactivity. Arousal is mediated by several neural systems.
Nonverbal autismNonverbal autism is a subset of autism where the person does not learn how to speak. It is estimated that 25% to 50% of children diagnosed with autism spectrum disorder (ASD) never develop spoken language beyond a few words or utterances. Most of the existing body of research in nonspeaking autism focuses on early interventions that predict successful language outcomes.
Group emotionGroup emotion refers to the moods, emotions and dispositional affects of a group of people. It can be seen as either an emotional entity influencing individual members' emotional states (top down) or the sum of the individuals' emotional states (bottom up). This view sees the group's dynamic processes as responsible for an elusive feeling state which influences the members' feelings and behavior. This view, that groups have an existence as entities beyond the characters that comprise them, has several angles.
Psychological painPsychological pain, mental pain, or emotional pain is an unpleasant feeling (a suffering) of a psychological, non-physical origin. A pioneer in the field of suicidology, Edwin S. Shneidman, described it as "how much you hurt as a human being. It is mental suffering; mental torment." There is no shortage in the many ways psychological pain is referred to, and using a different word usually reflects an emphasis on a particular aspect of mind life.