The Integrative Action of the Nervous System

The physiology of nervous reactions can be studied from three main points of view. In the first place, nerve-cells, like all other cells. lead individual lives,—they breathe, they assimilate, they dispense their own stores of energy, they repair their own substantial waste; each is, in short, a living unit, with its nutrition more or less centred in itself. Secondly, nervous cells present a feature so characteristically developed in them as to be specially theirs. But a third aspect which nervous reactions offer to the physiologist is the integrative . There is the co-ordination which a reflex action introduces when it makes an effector organ responsive to excitement of a receptor, all other parts of the organism being supposed indifferent to and indifferent for that reaction. A dissimilarity between nerve-trunk conduction and reflex-arc conduction which has often been stressed is the slowness of the latter as measured by the latent interval between application of stimulus and appearance of end-effect.