Van Gogh - Starry Night - Google Art Project.jpg
Van Gogh's The Starry Night, from 1889, shows changes in light and color as can appear with psychosis.[1][2][3]
SpecialtyPsychiatry, psychology
SymptomsFalse beliefs, seeing or hearing things that others do not see or hear, incoherent speech[4]
ComplicationsSelf-harm, suicide[5]
CausesMental illness (schizophrenia, bipolar disorder), sleep deprivation, some medical conditions, certain medications, drugs (including alcohol and cannabis)[4]
TreatmentAntipsychotics, counselling, social support[5]
PrognosisDepends on cause[5]
Frequency3% of people at some point in time (US)[4]

Psychosis is an abnormal condition of the mind that results in difficulties determining what is real and what is not.[4] Symptoms may include false beliefs (delusions) and seeing or hearing things that others do not see or hear (hallucinations).[4] Other symptoms may include incoherent speech and behavior that is inappropriate for the situation.[4] There may also be sleep problems, social withdrawal, lack of motivation, and difficulties carrying out daily activities.[4]

Psychosis has many different causes.[4] These include mental illness, such as schizophrenia or bipolar disorder, sleep deprivation, some medical conditions, certain medications, and drugs such as alcohol or cannabis.[4] One type, known as postpartum psychosis, can occur after childbirth.[6] The neurotransmitter dopamine is believed to play a role.[7] Acute psychosis is considered primary if it results from a psychiatric condition and secondary if it is caused by a medical condition.[8] The diagnosis of a mental illness requires excluding other potential causes.[9] Testing may be done to check for central nervous system diseases, toxins, or other health problems as a cause.[10]

Treatment may include antipsychotic medication, counselling, and social support.[4][5] Early treatment appears to improve outcomes.[4] Medications appear to have a moderate effect.[11][12] Outcomes depend on the underlying cause.[5] In the United States about 3% of people develop psychosis at some point in time.[4] The condition has been described since at least the 4th century BC by Hippocrates and possibly as early as 1,500 BC in the Egyptian Ebers Papyrus.[13][14]

Signs and symptoms


A hallucination is defined as sensory perception in the absence of external stimuli. Hallucinations are different from illusions, or perceptual distortions, which are the misperception of external stimuli. Hallucinations may occur in any of the senses and take on almost any form, which may include simple sensations (such as lights, colors, tastes, and smells) to experiences such as seeing and interacting with fully formed animals and people, hearing voices, and having complex tactile sensations. Hallucinations are generally characterized as being vivid, and uncontrollable.[15]

Auditory hallucinations, particularly experiences of hearing voices, are the most common and often prominent feature of psychosis. Up to 15% of the general population may experience auditory hallucinations. The prevalence in schizophrenia is generally put around 70%, but may go as high as 98%. During the early 20th century auditory hallucinations were second to visual hallucinations in frequency, but they are now the most common manifestation of schizophrenia, although rates vary throughout cultures and regions. Auditory hallucinations are most commonly intelligible voices. When voices are present, the average number has been estimated at three. Content, like frequency, differs significantly, especially across cultures and demographics. People who experience auditory hallucinations can frequently identify the loudness, location of origin, and may settle on identities for voices. Western cultures are associated with auditory experiences concerning religious content, frequently related to sin. Hallucinations may command a person to do something, which may be dangerous when combined with delusions.[16]

Extracampine hallucinations are auditory hallucinations originating from a particular body part (e.g. a voice coming from a person's knee).[16]

Visual hallucinations occur in roughly a third of people with schizophrenia, although rates as high as 55% are reported. Content frequently involves animate objects, although perceptual abnormalities such as changes in lighting, shading, streaks, or lines may be seen. Visual abnormalities may conflict with proprioceptive information, and visions may include experiences such as the ground tilting. Lilliputian hallucinations are less common in schizophrenia, and occur more frequently in various types of encephalopathy (e.g. Peduncular hallucinosis).[16]

A visceral hallucination, also called a cenesthetic hallucination, is characterized by visceral sensations in the absence of stimuli. Cenesthetic hallucinations may include sensations of burning, or re-arrangement of internal organs.[16]


Psychosis may involve delusional beliefs. Delusions are strong beliefs against the reality, or held despite contradictory evidence. Delusions are necessarily incongruent with societal norms, as some beliefs may constitute a delusion in certain cultures where they impact functioning, while they may be a perfectly normal belief in others. The distinguishing feature between delusional thinking and full-blown delusions is the degree with which they impact functioning. Multiple themes are common in delusions, although cultural norms are highly influential (e.g. religious content differing significantly across countries). The most common type of delusion is a persecutory delusion, where a person believes that an individual, organization or group is attempting to harm them. Other delusions include delusions of reference (beliefs that a particular stimulus has a special meaning that is directed at the holder of belief), grandiose delusions (delusions that a person has a special power or importance), thought broadcasting (the belief that one's thoughts are audible) and thought insertion (the belief that one's thoughts are not one's own). The DSM-5 characterizes certain delusions as "bizarre" if they are clearly implausible, or are incompatible within the cultural context. The concept of bizarre delusions has been criticized as excessively subjective.[16]

Historically, Karl Jaspers has classified psychotic delusions into primary and secondary types. Primary delusions are defined as arising suddenly and not being comprehensible in terms of normal mental processes, whereas secondary delusions are typically understood as being influenced by the person's background or current situation (e.g., ethnicity; also religious, superstitious, or political beliefs).[17]


Disorganization is split into disorganized speech or thinking, and grossly disorganized motor behavior. Disorganized speech, also called formal thought disorder, is disorganization of thinking that is inferred from speech. Characteristics of disorganized speech include rapidly switching topics, called derailment or loose association; switching to topics that are unrelated, called tangental thinking; incomprehensible speech, called word salad or incoherence. Disorganized motor behavior includes repetitive, odd, or sometimes purposeless movement. Disorganized motor behavior rarely includes catatonia, and although it was a historically prominent symptom, it is rarely seen today. Whether this is due to historically used treatments or the lack thereof is unknown.[16][15]

Catatonia describes a profoundly 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 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, decreased motivation, and reduced spontaneous speech. They lack interest and spontaneity, and have the inability to feel pleasure.[18]

Other Languages
العربية: ذهان
asturianu: Sicosis
azərbaycanca: Psixoz
বাংলা: সাইকোসিস
беларуская: Псіхоз
беларуская (тарашкевіца)‎: Псыхоз
български: Психоза
brezhoneg: Psikosis
català: Psicosi
čeština: Psychóza
dansk: Psykose
Deutsch: Psychose
eesti: Psühhoos
Ελληνικά: Ψύχωση
español: Psicosis
Esperanto: Psikozo
euskara: Psikosi
français: Psychose
Gaeilge: Síocóis
galego: Psicose
한국어: 정신증
հայերեն: Փսիխոզ
हिन्दी: मनस्ताप
hrvatski: Psihoza
Ido: Psikozo
Bahasa Indonesia: Psikosis
italiano: Psicosi
עברית: פסיכוזה
ქართული: ფსიქოზი
kurdî: Psîkoz
latviešu: Psihoze
lietuvių: Psichozė
magyar: Pszichózis
македонски: Психоза
مصرى: سيكوز
Bahasa Melayu: Psikosis
Mirandés: Psicose
Nederlands: Psychose
नेपाली: पागलपन
नेपाल भाषा: मनस्ताप
日本語: 精神病
norsk: Psykose
norsk nynorsk: Psykose
Перем Коми: Psikoz
polski: Psychoza
português: Psicose
română: Psihoză
русский: Психоз
Scots: Psychosis
shqip: Psikoza
Simple English: Psychosis
slovenčina: Psychóza
کوردی: سایکۆز
српски / srpski: Психоза
srpskohrvatski / српскохрватски: Psihoza
suomi: Psykoosi
svenska: Psykos
Tagalog: Sikosis
Türkçe: Psikoz
українська: Психоз
اردو: ذھان
Tiếng Việt: Loạn tâm thần
ייִדיש: פסיכאז
粵語: 思覺失調
中文: 思覺失調