Advanced near‐infrared light approaches for neuroimaging and neuromodulation

Abstract Almost all physiological processes of animals are controlled by the brain, including language, cognitive, memory, learning, emotion and so forth. Minor brain dysfunction usually leads to brain diseases and disorders. Therefore, it' is greatly meaningful and urgent for scientists to have a better understanding of brain structure and function. Optical approaches can provide powerful tools for imaging and modulating physiological processes of the brain. In particular, optical approaches in the near‐infrared (NIR) window (700–1700 nm) exhibit excellent prosperities of deep tissue penetration and low tissue scattering and absorption compared with those of visible windows (400–700 nm), which provides a promising approach for scientists to develop desired methods of neuroimaging and neuromodulation in deep brain tissues. In this review, variable types of NIR light approaches for imaging and modulating neural ions, membrane potential, neurotransmitters, and other critical molecules for brain functions and diseases are summarized. In particular, the latest breakthrough research of brain imaging and brain regulation in the NIR‐II window (1000–1700 nm) are highlighted. Finally, we conclude the challenges and prospects of NIR light‐based neuroimaging and neuromodulation for both basic brain research and further clinical translation.