Epileptiform Seizures From Chronic Isolated Cortex

Abstract

The present experiments are concerned with further evidence of the epileptogenic properties of chronic partially isolated (denervated) monkey cerebral cortex. Marshall Hall²⁹in 1841 remarked, "The first effect of injury done to the nervous system is a diminution of its functions; whilst the second or ulterior effect is the augmentation of those functions." In 1880 Claude Bernard³stated, "The excitability of all tissues seems to augment when they are separated from the nervous influences which dominate them." In subsequent years there followed a wide series of observations, largely on excitable peripheral structures, confirming and expanding the opinions of Hall and Bernard. In 1939 Cannon,⁹in his Hughlings Jackson lecture at the Montreal Neurological Institute, presented his Law of Denervation as follows: "When in a series of efferent neurones a unit is destroyed an increased irritability to chemical agents develops in the isolated structure or structures, the effects