agitated state in which the experience of reality is generally considered impaired. There are two primary manifestations of catatonic behavior. The classic presentation is a person who does not move or interact with the world in any way while awake. This type of catatonia presents with waxy flexibility. Waxy flexibility is when someone physically moves part of a catatonic person's body and the person stays in the position even if it is bizarre and otherwise nonfunctional (such as moving a person's arm straight up in the air and the arm staying there). The other type of catatonia is more of an outward presentation of the profoundly agitated state described above. It involves excessive and purposeless motor behaviour, as well as an extreme mental preoccupation that prevents an intact experience of reality. An example is someone walking very fast in circles to the exclusion of anything else with a level of mental preoccupation (meaning not focused on anything relevant to the situation) that was not typical of the person prior to the symptom onset. In both types of catatonia, there is generally no reaction to anything that happens outside of them. It is important to distinguish catatonic agitation from severe bipolar mania, although someone could have both. Negative symptoms Negative symptoms include reduced emotional expression (flat affect), decreased motivation (avolition), and reduced spontaneous speech (poverty of speech, alogia). Individuals with this condition lack interest and spontaneity, and have the inability to feel pleasure (anhedonia). Psychosis in adolescents Psychosis is rare in adolescents. Young people who have psychosis may have trouble connecting with the world around them and may experience hallucinations and/or delusions. Adolescents with psychosis may also have cognitive deficits that may make it harder for the youth to socialize and work. Potential impairments include the speed of mental processing, ability to focus without getting distracted (limited attention span), and deficits in verbal memory. If an adolescent is experiencing psychosis, they most likely have comorbidity meaning they could have multiple mental illnesses. Because of this, it can be difficult to determine if it is psychosis or autism spectrum disorder, social or generalized anxiety disorder, or obsessive-compulsive disorder. History Etymology The word psychosis was introduced to the psychiatric literature in 1841 by Karl Friedrich Canstatt in his work Handbuch der Medizinischen Klinik. He used it as a shorthand for 'psychic neurosis'. At that time neurosis meant any disease of the nervous system,