Korsakoff's syndrome

Korsakoff’s syndrome is a neurological condition characterized by severe memory loss and a loss of contact with reality which can result from chronic alcoholism and malnutrition. Brain damage occurs from cell loss in the thalamus and the hypothalamus. The condition is named after Sergei Korsakoff, a Russian physician who described the syndrome as a result of chronic alcoholism.

The first stage is accompanied by confusion, disorientation, tremors, a deficit in coordination and ataxia. The disorder progresses to a pattern of significant memory loss which impairs all but the distant past. Patients may not remember their career, where they are, or what they are doing. They often engage in confabulation by creating stories in response to questioning rather than admit an inability to remember. They create stories, usually nonsensical but sometimes rooted in fact, using fragment of memory and sensory information. They also display apathy towards their own state.

The memory impairment found in Korsakoff’s syndrome is most often a deficit in explicit memory. Neuronal death in the medial thalamus and mammillary bodies of the hypothalamus have provided evidence for a theoretical neural circuit for explicit memory. The other form is anterograde amnesia which is memory loss for information learned after the onset of the disorder. It appears anterograde memory is related to hippocampal white matter volume. A deficit in retrograde memory for previously learned information may also be present, although generally not as severe. This deficit is related to posterior coritcal white matter volume.

The syndrome is thought to be caused by a deficiency in thiamine (Vitamin B1) caused by poor diet and poor absorption during digestion. Alcoholics tend to have a poor diet, and alcohol diminishes nutrition absorption. Although thiamine is not the sole cause of the disorder, evidence from animal studies supports its importance. Animals fed on a thiamine deficient diet or treated with a thiamine antagonist show brain lesions in the same area of the brain, and have impaired learning and memory.

Treatment consists of vitamin B1, which can take the form of supplements or an enriched diet. Prognosis is poor, as most patients do not recover from this devastating loss of memory. The popular belief that alcohol permanently kills brain cells may not be completely true. While heavy and persistent alcohol consumption will cause brain damage, such as Korsakoff syndrome, neuronal death may not be permanent. Some research suggests axons may regrow in the cortex following extended abstinence. Regardless, research is conflicting and has not reached a consensus, and it is no reason to engage in unhealthy drinking.