Psychosis

Psychosis is a mental state in which the perception of reality is distorted. Persons having a psychotic episode may hear voices, have visual hallucinations, and exhibit paranoia and disorganized thinking. Typical beliefs held by persons undergoing a psychotic episode include thought broadcasting, thought reception, and delusions of grandeur. It is important to note that to be classified as psychotic, a patient's pattern of thinking must not be culturally sanctioned or shared by people with the same background. The medical term psychosis should also be distinguished from the concept of insanity which is a legal term denoting that a person should not be criminally responsible for his actions.

Psychosis may be the result of an underlying mental illness such as Bipolar disorder (also known as manic depression), and schizophrenia. Psychosis may also be exhibited by otherwise normal people who have undergone enormous mental stress or who have taken high doses of drugs such as amphetamines, PCP or scopolamine. This situation is known as "brief reactive psychosis", and in the absence of any mental illness, patients spontaneously recover normal functioning within two weeks.

The division of the major psychoses into bipolar disorder and schizophrenia was made by Emil Kraepelin, who attempted to create a synthesis of the hundreds of mental disorders identified by 19th century psychiatrists, by grouping diseases together based on classification of common symptoms. Bipolar disorder is characterised by problems with mood control and the psychotic episodes appear associated with disturbances in mood, and patients will often have periods of normal functioning between psychotic episodes even without medication. Schizophrenia is characterized by psychotic episodes which appear to be unrelated to disturbances in mood, and most non-medicated patients will show signs of disturbance between psychotic episodes. There is a growing consensus among psychiatrists that these differences can be coorelated with biological changes in the functioning of the brain.