20 Pages

Pathological States of the Cerebral Hemispheres as a Result of Functional Influences Exerted on Them37

WithIvan P. Pavlov

There are three types of stimuli: weak, monotonously recurring, very strong and, lastly, unusual stimuli generally represented either by new phenomena or a new connection, new sequence of old phenomena. If stimuli of considerable strength and, what is more important, constantly changing stimuli condition and must condition the active state of the cortex to maintain a fine balance of the organism with the environment, it is natural that weak and monotonous stimuli which do not require any activity from the organism must dispose to inhibition and rest, to give the cortical cells time for recovery after work. This chapter elucidates the derangements of higher nervous activity (“experimental neuroses”) produced by difficult tasks imposed on experimental animals and overstraining the basic nervous processes in the brain and the mobility of these processes.