FURTHER ANALYSIS OF EVOKED "SECONDARY DISCHARGE"; A STUDY IN RETICULOCORTICAL RELATIONS

Abstract

Simultaneous recordings of the saphenous compound action potential and evoked cortical potentials indicate that the primary and secondary discharge are evoked by stimulation of the same fibers peripherally, i.e., alpha-beta group. A distinct distribution pattern was mapped for the evoked secondary discharge on the cortex of the cat. This cortical map is characterized by potential maxima in the anterior lateral gyrus and is independent of the peripheral source of somatic nerve stimulation. The pattern is also reproducible by single shock stimulation of medial reticular regions of the brain stem and it is concluded that the ascending medial reticular system represents the common multi-synaptic relay station for the secondary discharge.