Concepedia

Abstract

It is the function of the sense organs to reflect, in the nervous activity they generate, the state of the organism's environment, initiating chains of neural events that regulate behavior. The mechanisms whereby environmental influences excite activity in afferent nerve fibers have been discussed by many authors. Nevertheless, it is not yet possible to trace, step by step, the physical and chemical events that intervene between the action of a stimulus on a receptor and the response of the associated afferent fiber. This paper will consider some of the ideas that have been developed, and add new observations that bear on the problem of the origin of nervous activity, with particular reference to the visual system.2