The Effects of Tonic and Burst Spinal Cord Stimulation on Cortical Pain Processing and Their Interaction With Conditioned Pain Modulation

This exploratory study indicates that evoked and induced cortical responses reflect distinct mechanisms during CPM under SCS. Evoked responses, which primarily reflect bottom-up sensory processing, may be reduced by tonic SCS in the ascending lateral pathway areas before CPM. This reduction may suggest that tonic SCS suppresses input of the ascending lateral pathway, limiting additional inhibition by CPM. Beta ERS (induced response), which primarily reflects top-down modulation, decreased during CPM under tonic and burst SCS, suggesting engagement of the descending pain pathway.