Electrical activity of the central nervous system of the frog
Careful exploration has been made of the electrical activity of the brain of various mammals (Adrian and Matthews 1934; Gerard, Marshall and Saul 1936; Gerard 1936 a and b ), but there has been very little study of the brains of other vertebrates (Adrian 1931; Umrath and Umrath 1934). The small size and relatively homogeneous cell population of the Amphibian brain offer certain advantages in analysis of the physicochemical factors determining activity; and further, the low metabolism of the poikilothermic brain at room temperature, together with the short distances for oxygen diffusion, suggested the possibility of studying sustained activity in the isolated organ. The present report covers a general exploration of spontaneous electrical changes in the neuraxis of the grass frog ( Rana pipiens ) and bull frog ( R. catesbiana ).