The results of experimentation already reported1 attest the theory that stimulation of the higher neural centers produces an inhibitory effect on the lower neural centers and that inhibition of the higher neural centers produces a stimulatory effect on the lower neural centers. In the past our application of the action current technic to the study of reflex time has omitted controlled direct stimulation of the nerve tissues. In the present study we shall consider the effect of direct stimulation of the brain and the spinal cord on reflex response latencies.
In the stimulation of any tissue, tissues circumjacent to the point of application are distantly affected by the stimulus. In this study we have applied a technic for measuring the degree of radiation of electric stimuli in nerve tissues.
APPARATUS AND PROCEDURE
For clearness of presentation this experimentation may be divided into two major parts: experiments on dogs and