10 - Memory and Cognitive Disorders of Chronic Alcoholics

Abstract

Evidence suggests that alcohol has a direct toxic effect on brain tissue that forces researcher to consider the possibility that Korsakoffs syndrome may be a chronic illness correlated with the degree and the length of alcohol abuse. This chapter discusses memory and cognitive disorders of chronic alcoholics. Continuities between alcoholic Korsakoff patients and long-term non-Korsakoff alcoholics have been demonstrated in numerous neuro-psychological investigations. When contrasted with nonalcoholic control subjects, both chronic alcoholics and alcoholic Korsakoff patients perform poorly on visuoperceptual tasks requiring digit-symbol substitutions or the identification of embedded figures. On these tests, the scores of the chronic alcoholics fall midway between those of the alcoholic Korsakoff patients and the nonalcoholic control group. However, the results of three separate studies suggest that chronic alcoholics and alcoholic Korsakoff patients do share qualitatively similar anterograde memory problems. Although it is not possible to determine what neural circuits mediate anterograde and retrograde memory processes, a report based on stimulation studies with epileptic patients has produced evidence for such an anatomical separation. Two distinct areas concerned with memory were found within the left temporal lobe: the stimulation of the posterior region resulted in retrograde memory problems, whereas the stimulation of the anterior region produced anterograde memory deficits.