Some properties of isolated cerebral cortex in the unanaesthetized cat

In an earlier paper an account was given of the preparation and some of the properties of a neurologically isolated slab of cerebral cortex, isolated in such a way that its blood supply was the only remaining connexion with the rest of the animal (Burns, 1949, 1950). In these experiments isolation produced a disappearance of the 'spontaneous' activity found in the lightly anaesthetized brain, although the cells within the isolated area had not apparently been injured by the surgical operation, for they would still respond to electrical stimulation applied through electrodes on the brain's surface. All these earlier experiments, however, were made with preparations in cats under light chloralose anaesthesia, and it seemed possible to ascribe the inactivity of the isolated cortex to the anaesthetic used. It was therefore necessary to extend these experiments to the unanaesthetized animal. Fortunately, it proved possible to decerebrate cats in such a way that a part of one cerebral hemisphere remained in the cranial cavity, with all its nervous connexions cut but with undisturbed blood supply. The experiments reported have all been carried out with such preparations. METHOD