Alcoholics and those with high intakes of alcohol such as chronic binge drinkers are at a greater risk of the neurological disorders including Wernicke­ Korsakoff syndrome (WKS). The damage associated with the structural brain changes seen in WKS include disturbed cognition, memory problems, reduced intellect and personality changes. One of the most serious effects of WKS is anterograde amnesia, which is the inability to learn from new memories, retrograde amnesia, which is the ability to recall memories from before the development of WKS, and impairment of several cognitive processes including concentration, learning and memory. As a result individuals can become easily distracted and unable to screen out unwanted information, whilst at the same time failing to focus on important information. These changes are associated with structural changes in the brainstem and the thalamus. Individuals with WKS also have problems separating sensations such as odours, colours or musical pieces and this is thought to relate to the fact that these perceptions originate in the thalamus. Further WKS sufferers also have impairments in language in the way they can analyse words and sentences and find it hard to evaluate at the orthographic graphic level by correctly using lower and upper case letters, at the phenomic level but understanding rhyming, or at the semantic level, to identify how words contextualise a sentence. 

One of the main factors that is thought to contribute to the development of WKS in alcoholics is a thiamin deficiency. This is significant because thiamine deficiency is known to be induced by chronic alcohol consumption in a number of ways including an increased excretion of the vitamin and a concomitant decreased absorption. Alcohol can also reduce intakes of thiamine rich foods because of the effects it has on inhibiting inhibitory control, which causes an increased intake of tastier but lower quality foods. As alcohol contains 7 kcals per gram, heavy drinkers often substitute food calories for alcohol calories, thus reducing their thiamin intakes significantly. Wernicke’s encephalopathy is a disease similar to WKS, that is known to be caused by thiamine deficiency in the absence of alcohol, and this condition can be reversed clinically by administration of thiamine. Thiamine deficiency is able to disrupt normal brain activity because it is required for glucose metabolism in the neurones, is required for the correct myelination of myelinated neurones and may be involved in maintaining membrane structure. Patients who present in hospital with chronic nutritional deficiencies including deficiencies of thiamine often have symptoms identical to WKS despite the absence of alcohol.  

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Langlais, P.J. 1995. Alcohol-related thiamine deficiency: Impact on cognitive and memory functioning. Alcohol Health and Research World. 19(2): 113