percent of alcoholics with Wernicke's Encephalopathy develop Korsakoff's psychosis (Butterworth, 1989). In economically advantaged countries such as the United States, where other forms of malnutrition are uncommon, thiamine deficiency and the resulting WKS occur most commonly among alcoholics. In postmortem studies, brain abnormalities characteristic of WKS were present in approximately 13 percent of alcoholics (Harper, 1988). However, thiamine deficiency resulting from chronic alcohol is also associated with general alcohol neurotoxicity and cerebellar degeneration without WKS (Martin et al., 1994). In addition, a subclinical thiamine deficiency during chronic heavy alcohol consumption can lead to significant cognitive impairments and reduced neuroplasticity (Vedder et al., 2015). The moderate association between a TPK1 SNP and alcohol dependence (Bierut et al., 2010), is supported by previous work showing a link between thiamine deficiency, neuropathology and associated cognitive impairments in cases of chronic alcohol consumption. Therefore, if the association with TPK1 is confirmed by future studies the genetic variation in TPK1 can be hypothesized to function in altering thiamine signaling and metabolism that affects alcohol dependence induced cognitive deficits and neuronal degeneration. This may have relevance to cognitive deficits associated with poor decision making that is characteristic of the preoccupation-anticipation addiction domain.
