Transparent Temperature Sensors for Photothermal Neuromodulation: Advances, Challenges, and Future Directions

Photothermal neuromodulation, a rapidly advancing technique in neuroscience, has been introduced as an incredibly versatile platform for the in‐depth study of neural electrophysiological signals and the development of treatments for various neurological disorders. Particularly, nanomaterial‐based photothermal neuromodulation technologies have advantages compared to optogenetic stimulation methods, such as non‐genetic modification, minimally invasive, and reduced immune response. Photothermal neuromodulation research has introduced various nanomaterials and stimulation methods to regulate thermosensitive ion channels or modify cell membrane capacitance, enabling excitation and inhibition of neural activity. Recent advances in nanomaterials have significantly improved the precision and efficiency of photothermal neuromodulation, expanding its potential applications in neuroscience research. In the photothermal neuromodulation studies, different temperature measurement methods have been used but do not satisfy all the requirements necessary to analyze this phenomenon. An ideal temperature sensor for a photothermal neuromodulation study must have high transparency, high thermal sensitivity, and high spatial and temporal resolution. This review aims to cover the current status of thermally induced neuromodulation studies and the transparent temperature sensing methodologies that can be used for photothermal neuromodulation.