Catatonia is a motor dysregulation syndrome involving difficulty initiating or terminating actions, which largely reflects dysfunction of the basal ganglia. Most commonly this causes periods of physical rigidity, negativism, or stupor (although psychomotor hyperactivity may also occur).
Although catatonia is traditionally associated with schizophrenia, it is more often triggered by acute medical illness or affective disorders (e.g., bipolar disorder). The diagnosis of catatonia in the context of psychiatric disorders can be challenging, as there may be overlapping features of both conditions.
Recognition of catatonia is essential because it is a highly treatable condition which responds to specific interventions. Alternatively, provision of nonspecific supportive care may often fail (especially in malignant catatonia). Catatonia is a spectrum disorder which varies in severity (rather than a binary, dichotomous condition).