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psychosis(sīkō`sĭs), in psychiatrypsychiatry
, branch of medicine that concerns the diagnosis and treatment of mental, emotional, and behavioral disorders, including major depression, schizophrenia, and anxiety.
..... Click the link for more information. , a broad category of mental disorder encompassing the most serious emotional disturbances, often rendering the individual incapable of staying in contact with reality. Until recently, the term was used in contrast with neurosisneurosis,
in psychiatry, a broad category of psychological disturbance, encompassing various mild forms of mental disorder. Until fairly recently, the term neurosis was broadly employed in contrast with psychosis, which denoted much more severe, debilitating mental disturbances.
..... Click the link for more information. , which denoted the "mild" mental disorders which did not interfere significantly with the ability to function normally, or severely impair the individual's conception of reality. In 1980, the American Psychiatric Association made sweeping changes in its classificatory system for psychological disorders, and the opposition between neurosis and psychosis became obsolete. The former classification included functional psychoses including schizophreniaschizophrenia
, group of severe mental disorders characterized by reality distortions resulting in unusual thought patterns and behaviors. Because there is often little or no logical relationship between the thoughts and feelings of a person with schizophrenia, the disorder has
..... Click the link for more information. , paranoiaparanoia
, in psychology, a term denoting persistent, unalterable, systematized, logically reasoned delusions, or false beliefs, usually of persecution or grandeur. In the former case the paranoiac creates a complex delusional system that purports to show that people want to
..... Click the link for more information. , bipolar disorderbipolar disorder,
formerly manic-depressive disorder
severe mental disorder involving manic episodes that are usually accompanied by episodes of depression.
..... Click the link for more information. , and involutional psychotic reactions, where no brain change was detectable with available tools. Today, there are separate categories for schizophrenic disorders, mood disorders (which include bipolar disorder and major depressiondepression,
in psychiatry, a symptom of mood disorder characterized by intense feelings of loss, sadness, hopelessness, failure, and rejection. The two major types of mood disorder are unipolar disorder, also called major depression, and bipolar disorder, whose sufferers are
..... Click the link for more information. ), and other serious mental disturbances such as delusional disorder. Symptoms of these disorders may include hallucinations and delusions; severe deviations of mood (depression and mania); lack of, or inappropriateness of, emotional response; and severe impairment of judgment. Another type of psychosis involves brief episodes, characterized by an acute onset lasting no longer than a month, usually resulting from situational circumstances such as an earthquake or flood. Nonspecified psychotic disorders include psychotic symptoms, e.g., delusions, hallucinations, or disorganized behavior, that cannot be classified in any other disorder. Drug therapy and electroconvulsive therapyelectroconvulsive therapy
in psychiatry, treatment of mood disorders by means of electricity; the broader term "shock therapy" also includes the use of chemical agents. The therapeutic possibilities of these treatments were discovered in the 1930s by Manfred Sakel, a Polish
..... Click the link for more information. have been successful in the treatment of many patients with serious psychological disorders. Organic psychoses, so called because of the structural deterioration of the brain, include senile dementiadementia
[Lat.,=being out of the mind], progressive deterioration of intellectual faculties resulting in apathy, confusion, and stupor. In the 17th cent. the term was synonymous with insanity, and the term dementia praecox was used in the 19th cent.
..... Click the link for more information. and Alzheimer's disease. Occurring in middle to old age, these disorders involve progressive, nonreversible brain damage. Organic brain damage may also result from toxic reactions to such substances as alcohol, PCP, amphetamines, and crack cocaine. In criminal law, the term insanityinsanity,
mental disorder of such severity as to render its victim incapable of managing his affairs or of conforming to social standards. Today, the term insanity is used chiefly in criminal law, to denote mental aberrations or defects that may relieve a person from the legal
..... Click the link for more information. can be applied to most forms of psychoses, although defenses based on insanity have been relatively rare.
Any disorder of higher mental processes of such severity that judgments pertaining to the reality of external events are significantly impaired. A wide range of conditions can bring about a psychotic state. They include schizophrenia, mania, depression, ingestion of drugs, withdrawal from drugs, liver or kidney failure, endocrine disorders, metabolic disorders, and Alzheimer's disease, epilepsy, and other neurologic dysfunctions. The dreams of normal sleep are a form of psychosis.
Psychotic alterations of beliefs are called delusions. Psychotic alterations of perception are referred to as hallucinations. Psychotic states that are due to alcoholism, metabolic diseases, or other medical conditions are frequently accompanied by general mental confusion. On the other hand, psychiatric illnesses and drugs can produce hallucinations and delusions in the absence of general confusion. Few of those symptoms are unique to a particular illness, which can make proper diagnosis difficult and challenging. Correct diagnosis, however, is critical so that appropriate treatment can be provided. See Addictive disorders, Affective disorders, Alzheimer's disease, Paranoia, Schizophrenia