Closed-loop and responsive neurostimulation

Current neuromodulation technology generally relies on tonic stimulation to change the function of the nervous system. The stimulation is manually adjusted based on clinical examination to optimize the treatment effect. Introduction of closed-loop control systems into these devices can dramatically increase the efficiency of these therapies. Closed-loop, responsive, and adaptive control strategies each have applications that can improve how we care for patients. Identification of appropriate biomarkers is key to maximizing the efficacy of these advances. Biomarkers can represent a wide variety of features associated with normal or pathologic states; measurement of those features and intelligent application of those data to control our neuromodulatory devices will transform neuromodulation from a trial-and-error palliation therapy into a personalized, optimized treatment to restore function. Closed-loop neuromodulation is currently being explored in the areas of pain, epilepsy, and movement disorders such as spinal cord injury and psychiatric conditions. Continued research and collaboration in the fields of sensor design, pathophysiology, signal processing, imaging, pharmacology, and surgical technique are needed to develop the devices we will use to restore patients to normal function.