Brain Stimulation Therapeutic Interventions in Neuropsychiatry: A Cambrian Explosion

Brain stimulation interventions alter neural activity by applying electrical, magnetic, sonic, or other forms of energy to the nervous system, using invasive or noninvasive methods. In recent years, the basic science and clinical science of neuromodulation have markedly advanced, and the evidence for clinical utility has resulted in new U.S. Food and Drug Administration (FDA) clearance for multiple forms of brain stimulation and multiple indications in neuropsychiatry. This review summarizes the status of the major brain stimulation interventions for neuropsychiatric disorders, emphasizing key strengths and challenges in their therapeutic application. It also discusses opportunities for additional breakthroughs in treatment in this rapidly advancing field. These topics include noninvasive techniques for focal intracerebral drug delivery that bypass the adverse effects linked to systemic pharmacologic administration; interventions that noninvasively stimulate deep or superficial brain targets without impacting surrounding tissue; interventions that, in addition to or instead of altering symptomatic expression, reduce stress sensitivity, enhance resilience, and prevent manifestation of neuropsychiatric disorders; and the development of responsive or closed-loop stimulation techniques whereby the timing and nature of the stimulation are adjusted based on personalized biomarkers of future pathological brain states. Finally, noninvasive brain stimulation interventions intended for home use have recently shown clinical utility and have received FDA clearance. The field of brain stimulation represents a paradigm shift that is revolutionizing therapeutics and mechanistic understanding in neuropsychiatry.