Savant syndrome () is a rare condition in which someone with significant mental disabilities demonstrates certain abilities far in excess of average. The skills that savants excel at are generally related to memory. This may include rapid calculation, artistic ability, map making, or musical ability. Usually, only one exceptional skill is present.Those with the condition generally have a neurodevelopmental disorder such as autism spectrum disorder or have a brain injury. About half of cases are associated with autism, and these individuals may be known as "autistic savants". While the condition usually becomes apparent in childhood, some cases develop later in life. It is not recognized as a mental disorder within the DSM-5.Savant syndrome is estimated to affect around one in a million people. The condition affects more males than females, at a ratio of 6:1. The first medical account of the condition was in 1783. Among those with autism, 1 in 10 to 1 in 200 have savant syndrome to some degree. It is estimated that there are fewer than a hundred prodigious savants, with skills so extraordinary that they would be considered spectacular even for a non-impaired person, currently living. Signs and symptoms
Savant skills are usually found in one or more of five major areas: art, memory, arithmetic, musical abilities, and spatial skills. The most common kinds of savants are calendrical savants, "human calendars" who can calculate the day of the week for any given date with speed and accuracy, or recall personal memories from any given date.
Disorganized schizophrenia, or hebephrenia, was a subtype of schizophrenia prior to 2013. Subtypes of schizophrenia were no longer recognized as separate conditions in the DSM 5, published in 2013. The disorder is no longer listed in the 11th revision of the International Classification of Diseases (ICD-11). Disorganized schizophrenia was classified within ICD-10 the existing classification, in practice, until January 1,  2022, as a mental and behavioural disorder,  because the classification was thought to be an extreme expression of the disorganization syndrome that has been hypothesized to be one aspect of a three-factor model of symptoms in schizophrenia, the other factors being reality distortion (involving delusions and hallucinations) and psychomotor poverty (lack of speech, lack of spontaneous movement and various aspects of blunting of emotion). Presentation
The condition is also known as hebephrenia, named after the Greek term for "adolescence" – ἥβη (hḗbē) – and possibly the ancient-Greek goddess of youth, Hebe, daughter of Hera. The term refers to the ostensibly more prominent appearance of the disorder in persons around puberty.The prominent characteristics of this form are disorganized behavior and speech (see formal thought disorder), including loosened associations and schizophasia ("word salad"), and flat or inappropriate affect. In addition, psychiatrists must rule out any possible sign of catatonic schizophrenia. The most prominent features of disorganized schizophrenia are not delusions and hallucinations, as in paranoid schizophrenia, although fragmentary delusions (unsystemized and often hypochondriacal) and hallucinations may be present.