A system and method for controlling non-paresthesia stimulation of neural tissue of a patient. The method delivers a non-paresthesia stimulation waveform, senses sensory action potential (SAP) signals from the neural tissue of interest, and analyzes the SAP signals to obtain SAP activity data for at least one of an SAP C-fiber component or an SAP A-delta fiber component. The method determines whether the SAP activity data satisfies a criteria of interest and adjusts at least one of the therapy parameters to change the non-paresthesia stimulation waveform when the SAP activity data does not satisfy the criteria of interest.