Catatonia is a medical syndrome. Like all medical syndromes it’s recognized by a characteristic set of signs and symptoms. In this case, while it can be seen in psychiatric settings, catatonia is in fact recognized by the presence of motor and behavioral abnormalities not typically seen in psychiatric patients. Among these are abnormal postures, lack of speech, abnormal motor tone, lack of behavioral activity or occasionally excess behavioral activity, and certain odd behaviors.
In the very classic form of catatonia (an example of which from an old German medical textbook is shown on the home page of this website) many of the behavioral abnormalities are often readily apparent. Most prominent among these is often posturing where the patient maintains an unusual or uncomfortable posture of the limbs such as the image shows, or the patient may just remain in an ordinary mundane posture — such as sitting in one position in one particular place for a very long period of time. Often found in association with this abnormal posture of the body is mutism, which means that the patient doesn’t speak at all, very minimally, or just in a soft whisper. In addition to the posturing the patient may have negativism, which is a resistance to being passively moved out of the position they are maintaining. In many settings, posturing, immobility, mutism and negativism are among the most frequent catatonic signs comprising the most dominant elements of the catatonic syndrome.
Other catatonic signs represent unusual interactions with the environment or with the examiner. An example is repeating the words spoken (echolalia) or the movements made (echopraxia) by people interacting the patient. Surprisingly, this mimicking of speech or behavior often occurs when the patient is otherwise mute and uncommunicative. Another unusual interactive behavior is automatic obedience, where the patient will almost reflexively respond to a gesture– such as when the examiner extends his hand as if to shake hands– and the patient “automatically” begins to shake their hand, even when otherwise uncommunicative for failing to respond to other commands that are expressed verbally. Another of these unusual behaviors is ambitendency, where then patient seems “stuck” in the middle of a movement or behavior.
Some patients will have catatonic signs that represent over-activity. Among these is verbigeration, which is the repeating of a phrase over and over like a broken record. Other patients may show highly repeated behaviors such as mannerisms, which are often odd-looking such as saluting or using unusual gestures. Stereotypies are also other forms of repeated behaviors, which are not in themselves odd, such as rocking or rubbing movements. A very uncommon catatonic sign is excitement, where the patient is unpredictably hyperactive and possibly aggressive.
As a clinical syndrome, defining the presence of the signs and symptoms makes the diagnosis of catatonia. In our research developing the Bush-Francis Catatonia Rating Scale about 20 years ago, we provided a listing of 14 signs and symptoms to be assessed systematically for making a research diagnosis. Each of these catatonic signs was operationally defined on this rating scale with “anchored” scoring for severity. Finding the presence of at least 2 of the 14 items could make a research diagnosis. The Bush-Francis scale also includes an additional 9 signs, (for a total of 23 signs) which can be rated on a 3-point scale each to gauge severity.
The official clinical diagnostic system in its current edition (DSM-5, 2013) defines catatonia in a very similar fashion requiring 3 out of 12 signs. These 12 signs are also found among the 14 screening items from the Bush-Francis scale. Diagnoses made by either the Bush-Francis or the DSM-5 criteria almost always agree.
In special populations, such as patients with severe medical illness in an intensive care unit or patients with neurological disease, it may be necessary to use a more “stringent” set of criteria for a correct diagnosis of catatonia. This might include requiring 3 or 4 signs because of counfounding.
Sometimes the manifestations of catatonia can be subtle and are missed even by careful clinical examiners. Among the psychiatric conditions where confusion may occur is severe depression, where a patient may be minimally verbal and not physically active. A host of neurological disorders, including movement disorders and various forms of seizures can also be confusing to separate from catatonia.