Electroencephalographic signs of ethanol tolerance and physical dependence in the cat

Spontaneous electrical activity was recorded from three cortical and five subcortical sites, via permanently implanted electrodes, in five conscious, freely-moving adult cats. Initial observations were made during and after an intravenous infusion of ethanol, 1 g/kg. The animals then received ethanol by gastric intubation, in doses of 1.5 g/kg every 8, 12 or 24 h, for a period of 5 weeks. Electrical and behavioral observations were repeated on the day following the last gavage, before and during another intravenous infusion of ethanol 1 g/kg. All animals showed EEG changes which are interpreted as signs of tolerance to and dependence on alcohol. EEG changes appeared up to a day earlier than gross behavioral signs of alcohol withdrawal.