The Relation of Science and Religion.pdf - Online Christian Library

HIGHER ORGANISMS. 231of opinion concerning the interpretation ofthe facts, it can not be disputed that by directingthe electrode on certain well definedareas of the surface of the brain, it is possibleto bring into natural activity certain portionsof the muscular system, as controlled by themotor nerves.The plan adopted is, after putting the animalinto an insensible state by use of chloroform,and removing the cranium so as toexpose the brain, to apply the electrode co11-nected with an electric battery to a givenpoint on the surface, record the result, andgradually shift the needle round the originalspot until a new result is obtained, in whichthe spot previously tested becomes an indexfor the boundary of one circle, and this marksthe fact that a new circle has been entered.By this process of investigation a series ofcentres for active stimulation have been discovered.These number, i11 the brain of the rat,six; in the brain of the rabbit, seven; of the cat,eleven; of the dog, thirteen; and of the monkey,at least, seventeen. A curious limitationto the area of experiment has been encounteredhere, for all the centres identified arefound to cluster over the central region of the