EFFECT OF AFFERENT IMPULSES ON CORTICAL SUPPRESSOR AREAS

Abstract

Afferent no-ciceptive impulses initiated by electrical or mechanical stimulation of the sciatic nerve, injn. of hypertonic NaCl soln. into a muscle, or stretching of a contractured muscle led to an excitation of the suppressor as well as the sensori-motor and projection areas of the cortex. Quantative expts. show similar reactions to threshold and suprathreshold stimuli. The excitatory process seems to be based on a diminished synchronization and on recruitment of additional cortical neurons. Since it is probable that the degree of activity of the suppressor areas as recorded by the electrocorticogram is an indicator of the degree of suppression exerted by them on the motor of sensory cortex, it is tentatively suggested that the suppressor areas are involved in a homeostatic mechanism, which is called into action by afferent impulses.