These symptoms are called stupor, catalepsy, waxy flexibility, mutism, negativism, posturing, mannerisms, stereotypies, psychomotor agitation, grimacing, echolalia, and echopraxia.

The DSM-5 defines catatonia as “a syndrome characterized by lack of movement and communication, along with three or more of the following 12 behaviors; stupor, catalepsy, waxy flexibility, mutism, negativism, posturing, mannerism, stereotypy, agitation, grimacing, echolalia, or echopraxia.”[9] As a syndrome, catatonia can only occur in people with an existing illness.

Historically, the Wernicke-Kleist-Leonhard School considered periodic catatonia a distinct form of "non-system schizophrenia" characterized by recurrent acute phases with hyperkinetic and akinetic features and often psychotic symptoms, and the build-up of a residual state in between these acute phases, which is characterized by low-level catatonic features and aboulia of varying severity.

[17] Psychodynamic theorists have interpreted catatonia as a defense against the potentially destructive consequences of responsibility, and the passivity of the disorder provides relief.

[18] Catatonia is also seen in many medical disorders, including encephalitis, meningitis, autoimmune disorders,[19] focal neurological lesions (including strokes),[20] alcohol withdrawal,[21] abrupt or overly rapid benzodiazepine withdrawal,[22][23][24] cerebrovascular disease, neoplasms, head injury,[9] and some metabolic conditions (homocystinuria, diabetic ketoacidosis, hepatic encephalopathy, and hypercalcaemia).

The research is limited, but some evidence suggests that people can develop catatonia after traumatic brain injury without a primary psychiatric disorder.

This is thought to occur due to thyroid hormones impact on metabolism including in the cells of the nervous system.

HIV and AIDS can cause catatonia, most likely by predisposing one to infections in the brain, including different types of viral encephalitis.

High dose and chronic use of stimulants like cocaine and amphetamines can lead to cases of catatonia, typically associated with psychosis.

Notably, glutamate increases tells the neuron it acts on to fire, by binding to the NMDA receptor.

[41][42] : 134–5 Catatonia is diagnosed by the presence of three or more of the following 12 psychomotor symptoms in association with a mental disorder, medical condition, or unspecified:[41]: 135 Other disorders (additional code 293.89 [F06.1] to indicate the presence of the co-morbid catatonia): If catatonic symptoms are present but do not form the catatonic syndrome, a medication- or substance-induced aetiology should first be considered.

[43] ICD-11 classification In the ICD-11, catatonia is defined as a syndrome of primarily psychomotor disturbances that is characterized by the simultaneous occurrence of several symptoms such as stupor, catalepsy, waxy flexibility, mutism, negativism, posturing, mannerisms, stereotypies, psychomotor agitation, grimacing, echolalia, and echopraxia.

For this reason, physicians may overlook signs of catatonia due to the severity of the psychosis the patient is presenting with.

Therefore, the results of laboratory tests need to be considered in the context of clinical history, review of medications, and physical exam findings.

Therefore, a careful and detailed history, medication review, and physical exam are key to diagnosing catatonia and differentiating it from other conditions.

[72][47] Excessive glutamate activity is believed to be involved in catatonia;[73] when first-line treatment options fail, NMDA antagonists such as amantadine or memantine may be used.

Amantadine may have an increased incidence of tolerance with prolonged use and can cause psychosis, due to its additional effects on the dopamine system.

Memantine has a more targeted pharmacological profile for the glutamate system, reduced incidence of psychosis and may therefore be preferred for individuals who cannot tolerate amantadine.

[74] There are many medications that are known to cause catatonia in some people including steroids, stimulants, anticonvulsants, neuroleptics or dopamine blockers.

[78] Catatonia can occur at any age, but is most commonly seen in adolescence or young adulthood or in older adults with existing medical conditions.

In ancient China, the first descriptions of people that appear in the Huangdi Neijing (The Yellow Emperor's Inner Canon),[83] the book which forms the basis of Traditional Chinese Medicine.

It is thought to have been compiled by many people over the course of centuries during the Warring States Period (475-221 BCE) and the early Han Dynasty (206 BCE-220 CE).

[84] He viewed catatonia as its own illness, which would get worse over time in stages of mania, depression, and psychosis leading to dementia.

Kraeplin associated catatonia with a psychotic disorder called dementia praecox, which is no longer used as a diagnosis, but heavily informed the development of the concept of schizophrenia.

Kraeplin's work influenced two other notable German psychiatrists, Karl Leonhard and Max Fink, and their colleagues to expand the concept of catatonia as a syndrome which could occur in the setting of many mental illnesses, not just psychotic disorders.

Additionally, Leonhard and his colleagues categorized catatonia as either systematic or unsystematic, based on whether or not symptoms happened according to consistent and predictable patterns.

In fact, catatonia was a subtype of schizophrenia as recently as the DSM-III, and was not revised to be able to be applied to mood disorders until 1994 with the release of the DSM-IV.

In the latter half of the 20th century, clinicians observed that catatonia occurred in various psychiatric and medical conditions, not exclusively in schizophrenia.

Max Fink and colleagues advocated for recognizing catatonia as an independent syndrome, highlighting its frequent association with mood disorders and responsiveness to treatments like benzodiazepines and ECT.

In many cases, media portrayals reduce it to a stereotypical "frozen state," similar to a coma, failing to capture the complexity of symptoms like stupor, agitation, and mutism.