deep brain stimulation (DBS)

Deep brain stimulation is, in plain terms, a pacemaker for the brain. Thin electrodes are placed deep inside the brain, and a small device implanted in the chest sends steady electrical pulses along them, quieting the faulty activity that causes certain symptoms.

It is best known for Parkinson's disease and essential tremor, where the pulses can dramatically calm the shaking and stiffness that medication alone no longer controls. The same approach is used or studied for other conditions, from dystonia to some treatment-resistant psychiatric disorders.

DBS is a close cousin of brain–computer interfaces: both put electrodes in contact with neural tissue, but classic DBS mainly stimulates rather than decodes. It matters as a model because it is clinically established and widely used — proof that implanted neural devices can be safe, durable, and life-changing.