Stupor

Stupor
A patient in catatonic stupor
Classification and external resources
Specialty	Psychiatry
ICD-10	R40.1
ICD-9-CM	780.09
MeSH	D053608
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Stupor (From Latin stupere, "be stunned or amazed") is the lack of critical mental function and a level of consciousness wherein a sufferer is almost entirely unresponsive and only responds to base stimuli such as pain. Those in a stuporous state are rigid, mute and only appear to be conscious, as the eyes are open and follow surrounding objects. The word derives from the Latin ("numbness, insensibility"). Being characterized by impairments to reactions to external stimuli, it usually appears in infectious diseases, complicated toxic states, severe hypothermia, mental illnesses (e.g. schizophrenia, severe clinical depression), epilepsy, vascular illnesses (e.g. hypertensive encephalopathy), shock (e.g. learning of a death or surviving a car crash), neoplasms (e.g. brain tumors), vitamin D deficiency and other maladies.

If not stimulated externally, a patient with stupor will be in a sleepy state most of the time. In some extreme cases of severe depressive disorders the patient can become motionless, lose their appetite and become mute. Short periods of restricted responsivity can be achieved by intense stimulation (e.g. pain, bright light, loud noise, shock).

Lesions of the ascending reticular activation system on height of the pons and metencephalon have been shown to cause stupor. The incidence is higher after left-sided lesions.

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