Ethanol reduces rCFB activation of left dorsolateral prefrontal cortex during a verbal fluency task

In a previous study in normal subjects (Wendt et al., 1994), using a revers ing checkerboard as activation stimulus, we found that the coupling between local neuronal activity and regional cerebral blood flow was preserved fol lowing ethanol, and that a right-sided occipital activation response seen d uring sobriety became symmetrical during inebriation. In the present study we investigated if ethanol has a detrimental effect also on the activation of the left dorsolateral prefrontal cortex found in normals during verbal f luency. Measurements of regional cerebral blood flow in 20 healthy, young, male, right-handed volunteers during rest and verbal fluency were made duri ng sobriety and inebriation (0.06% blood alcohol concentration) with a I-we ek interval. We found a decrease in word production during inebriation. The normal activation within the frontotemporal part of the left dorsolateral prefrontal cortext was preserved during inebriation. The activation of this region seems thus to be robust to the effects of ethanol. During inebriati on no activation response to the word fluency test was found in the anterio r prefrontal part of the dorsolateral prefrontal cortex. This region is imp ortant for working, temporal, and short-term memory functions, processes th at are affected by ethanol. Hemispheric functioning and specialization seem to be adversely affected by ethanol, regardless of which hemisphere is mos t involved while sober. (C) 2001 Academic Press.