Korsakoff's syndrome

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Revision as of 04:53, 28 April 2008

Overview

Korsakoff's syndrome is a degenerative neurological condition caused by a deficiency in thiamine, a result of alcoholism and malnutrition.

Causes

Korsakoff's syndrome, first studied and documented by Korsakoff in the late 1890s, is caused by a deficiency in thiamine (vitamin B-1) from long-term alcohol abuse, and a poor diet often associated with longtime alcoholism. Korsakoff's disease seems to result from extensive bilateral damage to the frontal lobe and frontal lobe atrophy, as well as damage to the medial thalamus, and bilateral damage to the mamillary bodies.

Symptoms

The disorder is characterized by three symptomatic features: anterograde amnesia, retro grade amnesia, and confabulation. Anterograde amnesia and retrograde amnesia affect the memories stored in the brain from before and after the disease, and the effects can destroy one's ability to access long-term memory and form new short-term memories. The amnesia is due to the degeneration of the hippocampus. Confabulation is the filling-in of memory gaps by Korsakoff's patients in their semantic and episodic memories. Other symptoms can include tremors and/or ataxia (lack of muscle coordination). Patients with Korsakoff's syndrome often demonstrate other symptoms such as apathy and a lack insight, but their IQ and reasoning seems to be unaffected.

Treatment and Prognosis

While the most severe stages of the condition lead to coma and death, if caught early enough, recovery can be made through the use of intravenous thiamine supplements, and by improving general health and nutrition. The brain damage that occurs during the disease, however, is irreversible.

Examples

H.M. (patient) is a well-known case of the global amnesia caused by Korsakoff's syndrome. Patients suffering from herpes simplex encephalitis may also exhibit Korsakoff's symptoms such as difficulty in memory storage and retrieval.