STUDIES ON IRRADIATED CEREBRAL DIFFERENTIATED EXCITATION AND INHIBITION AS INDICATED AND MEASURED BY RESPIRATION

Abstract

Control tests before conditioning produced subcortically: from olfactory stimulation[long dash]inhibition of respiration; from general cutaneous stimulation[long dash]either inhibition or excitation; from auditory or optic stimulation[long dash]no change except for the first few tests. Thoracic respiration showed the following changes after conditioned differentiation had been established with auditory, olfactory, general cutaneous and optic analysers. 1. A correct positive or an incorrect negative conditioned test demonstrated excitation in all dogs. 2. A correct negative or incorrect positive conditioned test exhibited marked inhibition with the excitable or easily inhibited dog, while the evenly balanced or neutral dog disclosed slight or no inhibition. A series of alternate negative and positive conditioned foreleg reflexes and their corresponding changes of respiration may occur correctly when the tests are only a few seconds apart and when respiration (motor area) is still in a state of inhibition or excitation from the previous test. A possible contest for supremacy is suggested by the presence of waves of excitation and inhibition, correct and incorrect, in the respiratory records of some of the dogs which had difficulty in responding correctly to the differential tests. 2 or more responses of the foreleg during a positive conditioned test were usually accompanied by separate waves of excitation of respiration or intensifications of the common wave. Termination of the inhibitory or excitatory effect on respiration was often followed by a rebound. Likewise the excitable dog upon finishing a correct negative test frequently flexed the foreleg. There are apparently 3 kinds of instantaneous cerebral excitation and inhibition (suppression): 1, direct to lower areas; 2, incorrect; 3. correct. The selection of respiration as the mechanism for indicating and measuring the irradiated cerebral excitation and inhibition accompanying the positive and negative foreleg reflexes utilized in correct conditioned differentiation appears to be well justified by the results of this study. It is apparent for dogs that this high order of excitation and suppression takes priority over all others.