Alcohol reduces prefrontal cortical excitability in humans: A combined TMS and EEG study

Abstract

The effects of alcohol(0.8g/kg) on the prefrontalcortex were studied in nine healthy subjects using the technique of transcranial magnetic stimulation (TMS) combined with electroencephalography (EEG). A totalof 120 magnetic pulses were delivered with a figure-of-eight coilto the left prefrontalcortex at the rate of 0.4-0.7 Hz. The EEG was recorded simultaneously with 60 scalp electrodes (41 electrodes were used for analysis); the TMS-evoked activation was estimated by the area undertheglobalmean field amplitude (GMFA);time curve. TMS caused changes in EEG activity lasting up to 270 mspoststimulus. Alcoholdecreased GMFA at 30-270 mspoststimulus;(713 ± 303 vs 478 ± 142 µV ms; p=0.007). Alcohol-induced differences were most pronounced at anterior electrodes. These results;suggest that alcoholreduces the excitability in the prefrontalcortex. © 2003 American College of Neuropsychopharmacology.