a reorganization or compensatory mechanism in problem solving (Crego et al., 2010). These alterations in PFC activity may go unnoticed under low-level cognitive demands but may underlie deficits associated with higher-order cognitive function. Reduced glucose metabolism in alcohol-dependent subjects has been identified in mediofrontal and left dorsolateral PFC (Dao-Castellana et al., 1998). Decreases in medial frontal cortex glucose metabolism have been correlated with poor performance on the Wisconson Card Sorting Task in alcoholic subjects (Adams et al., 1993). It seems, though, that frontal glucose metabolism increases after a period of abstinence, suggesting that some behavioral consequences of chronic alcohol use may be reversible (Volkow et al., 1994). Indeed, abstinent subjects in one study demonstrated an increase in cognitive and executive functioning that was correlated with an increase in frontal glucose metabolism (Johnson-Greene et al., 1997).
