Abstract

Neuromodulation is the technique used to maintain neuroregulation and homeostasis in the body through neural signals with electrical or magnetic modes of stimuli. The brain has the capacity to undergo neuronal plasticity, which can be positive or negative according to the surrounding environment. Neuromodulation could be either invasive or non-invasive depending on the requirements. Invasive techniques such as spinal cord stimulation, deep brain stimulation, trigeminal nerve stimulation, peripheral nerve stimulation, cervical nerve stimulation, etc., which works by surgically placing electrodes inside the neural tissue. On the other hand, non-invasive neuromodulation or brain stimulation (NIBS) which is much safer, accessible, and less side effects or limitations and involve techniques such as transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), transcranial Random noise stimulation (tRNS), transcutaneous auricular vagus nerve stimulation (taVNS). These techniques are widely used for the treatment of neurological and psychological disorders with fair results observed in various clinical conditions. These NIBS techniques have the advantage of lower cost, applicability at home, and can be combined with training or rehabilitation. In this review, we will discuss neuromodulation techniques in brief, and neurological and psychiatric disorders in which these modalities can be considered as management with expert supervision, and the future direction of neuromodulation.