Brain stimulation refers to a range of techniques that involve applying electrical or magnetic stimulation to specific areas of the brain in order to modulate brain activity. This can include techniques such as transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), and deep brain stimulation (DBS). These techniques have been used in research and clinical settings to study brain function, treat neurological and psychiatric disorders, and enhance cognitive performance. Brain stimulation has shown promising results in treating conditions such as depression, Parkinson's disease, and chronic pain, and is an area of active research for potential applications in other areas of brain health and performance.