Systems and methods for using electrospinogram signals for closed loop control in Spinal Cord Stimulation therapy

A method of operating an implantable medical device (IMD) comprising an implantable pulse generator (IPG) and a plurality of electrodes configured to contact a patient's tissue, the method comprising:

• providing sub-threshold stimulation at at least one of the electrodes, wherein the stimulation is configured to not evoke paresthesia in the patient;
• sensing a stimulation artifact at one or more sensing electrodes, wherein the stimulation artifact comprises a signal formed by an electric field induced in the tissue by the stimulation;
• determining at least one stimulation artifact feature of the sensed stimulation artifact;
• determining at least one predicted neural feature from the determined at least one stimulation artifact feature using a prediction model that is configured to predict one or more neural features based on one or more stimulation artifact features, wherein the one or more neural features are indicative of a neural response to the stimulation;
• and
• using the determined at least one predicted neural feature to adjust the stimulation.