Electroencephalogram in the permanently isolated forebrain of the cat

The cerebral cortex of cats with chronic or permanent mesencephalic transections of the brain stem showed both high-voltage, slow-wave synchronized electroencephalographic patterns and low- voltage, fast-wave desynchronized rhythms when studied postoperatively. The alternation of sleep and wakefulness electrical activity in the permanently isolated forebrain is contrasted with the observations of Bremer in the acute "cerveau isolé" preparation.