Responses to Stimulation

Abstract

Unlike the previous section in which we were concerned with the examination of a variety of spontaneous or endogenous action potentials, the experiments in this section will involve stimulation. The first two (Experiments 8 and 9) require stimulation of the receptors of an animal with the energy type that they normally detect in nature (light, mechanical touch, or contact). In the first instance the recording is of the bioelectrical transducer action of the photoreceptors themselves; in the second case, the responses are detected from the giant internuncial fibers in the central nervous system to which the sensory fibers transmit their signals through synapses. In the normal course of events, these giant fibers would connect with motor fibers going to the periphery so that appropriate motor responses would occur. These actions comprise the elements of the classical stimulus-response chain and they are shown diagrammatically in Fig. 16.