Neurobehavioral sequelae of alcoholism

Chronic alcohol abuse is associated with a wide range of cognitive deficits, including impairment in perceptual-motor skills, visual-spatial functions, learning/memory, and abstraction and problem solving. In Korsakoff patients, despite normal IQs, these deficits are pronounced, especially in episodic memory and new learning. Procedural memory (learning of simple, repetitive skills), however, is relatively intact. New evidence suggests that orbitobasal frontal lobe dysfunction in addition to diencephalic lesions contributes to the deficits found in Korsakoff patients. A genetically controlled thiamine deficiency has been hypothesized to account for the development of the Wernicke-Korsakoff disorder. Prognosis for the recovery from Korsakoff's syndrome is poor, although evidence suggests that these patients should be able to learn simple repetitive tasks involving procedural memory. In non-Korsakoff sober alcoholics the aforementioned cognitive deficits are less severe but nonetheless significant. These performance deficits are not easily accounted for by the current neuropsychologic hypotheses, although neuroanatomic changes frequently accompany chronic alcohol abuse. Family history, although a significant predictor of later alcoholism, does not appear to play a major role in determining alcohol-related cognitive deficits. A history of childhood behavioral disorders is associated with greater cognitive impairment. The means by which its effect is expressed, however, is unclear. The most parsimonious explanation focuses on the possibility that these disorders are the manifestation of inherited temperament traits that increase vulnerability to a variety of negative outcomes including antisocial personality and alcoholism. Significant recovery of cognitive function can occur but may be contingent on factors such as age and continued abstinence.