Optical neuromodulation: Exploring light-based approaches for neural circuit modulation

The nervous system functions as the body's control center, coordinating its activities through a network of nerves, resulting in the formation of tightly controlled interconnected circuits. Any disruption in these circuits leads to impaired nervous system function and can affect other organ systems. Neuromodulation techniques are employed to repair or replace these damaged circuits. Since traditional neuromodulation using electricity has drawbacks, alternative methods are being explored. One such method is "Optical Neuromodulation," which uses light. Various studies have been reported wherein light has been used to stimulate or inhibit neural activity. Additionally, certain studies report the combination of light and other forms of neuromodulation in order to improve the process. All the methods developed have their own merits and demerits. This review aims to explain optical neuromodulation, the different techniques developed, and the science behind them.