Background. Neuropsychological and imaging studies suggest
frontal dysfunction may occur in apparently normal chronic alcoholic subjects.
Methods. To investigate this issue further, we performed neuropsychological
and fluorodeoxy-glucose-PET studies in 17 chronic alcoholics without
patent neurological and psychiatric complications.
Results. Metabolic abnormalities were found in the mediofrontal
and in the left dorsolateral
prefrontal cortex, but not in the orbitofrontal cortex. Neuropsychological
significantly reduced verbal fluency and impaired performance on the Stroop
test. The mediofrontal
hypometabolism correlated with the reduction in verbal fluency and the
time necessary to perform
the interference condition of the Stroop test. The left dorsolateral prefrontal
correlated with the number of errors on the Stroop test.
Conclusion. These data indicate that circumscribed frontal
dysfunctions may occur in chronic
alcoholic subjects before clinically obvious neurological complications,
and may account for some
of the alcohol-related neuropsychological and behavioural impairments.