In one embodiment, a deep brain stimulation (DBS) system for electrically stimulating a target location in the brain of a patient, comprises: pulse generating circuitry for generating electrical pulses; at least one electrical lead for conducting electrical pulses generated by the pulse generating circuitry to the target location using one or several stimulation electrodes, wherein the at least one electrical lead further comprises one or several electrochemical sensors for sensing an extracellular level of one or several neurotransmitters and/or precursors; and a controller for controlling the pulse generating circuitry using closed-loop feedback based upon the extracellular level of the one or several neurotransmitters, wherein the controller for controlling the pulse generating circuitry processes the extracellular level of the one or several neurotransmitters using a measured impedance between one or several of the electrochemical sensors and a reference electrode.
Closed-loop deep brain stimulation system adapted to accommodate glial scarring and method of operation