To examine how ethanol interferes with brain function on the global levels of brain activity reflected by event-related potentials, we summarize here our recent efforts to characterize the acute cellular effects of ethanol. Four regions of the rodent brain (cerebellum, hippocampus, locus coeruleus and inferior olive) have so far been examined. The effects of acute parenteral ethanol on specific identifiable neurons within these 4 regions are highly consistent, dose-related, and spontaneously reversible. Furthermore, different patterns of response are seen in each responsive region, ranging from general increased firing in inferior olive to generally depressed synaptic transmission in hippocampus, and with more subtle effects within the cerebellum and within the locus ceruleus. This survey of consistent but differing patterns of responsiveness to ethanol at specific time points after acute exposure, suggests that the global effects of ethanol must be composed of several distinct effects both within and across many cellular systems.