ETHANOL REDUCES ASYMMETRY OF VISUAL RCBF RESPONSES

Visual regional CBF (rCBF) responses were measured in 10 healthy male subjects before and after an ethanol dose of 1 g/kg body weight. This dose induces well-established cerebral vasodilatation. However, signif icant bilateral occipital increases were found in both conditions. App arently, the coupling between neuronal activity and rCBF is preserved following ethanol. The oc cipital and posterior parietal flow increase s were, however, larger on the right than the left side in the sober s tate. During inebriation the asymmetry disappeared, possibly represent ing a more undifferentiated processing of visual information. We propo se that ethanol causes a reduced inhibition of the left posterior cort ex and a reduction of right-hemisphere information processing.