**3. Deep brain stimulation (DBS)**

DBS is an electrode implantation method using stereotactic techniques into the deep regions of brain for modulating neuronal function. An implantable pulse generator (IPG) is attached below the clavicle region, with an intention to treat neurological and psychiatric conditions. This attached IPG works on battery and delivers electrical stimulation, which is regulated externally by patients with the help of the remote. The electronic components like frequency, pulse, voltage, and other parameters can be altered to attain maximum efficacy of the treatment. It is believed that it works on excitation and inhibition of neurons present nearby the electrodes, but the exact mechanism is still unknown.

Low-frequency stimulation seems to excite nearby neurons, while high-frequency stimulation may decrease local activity leading to rescindable functional lesion. This simple-minded opinion for the mechanistic action has been a challenge in recent years, and more comprehensive knowledge may promote enhanced DBS treatments [8].
