Nonthermal and reversible control of neuronal signaling and behavior by midinfrared stimulation

Abstract

Significance Infrared neural stimulation (INS) is an emerging technology for neuromodulation and holds promise for clinical application. While most INS studies have been conducted at near-infrared wavelengths, whether midinfrared light with frequencies matching the chemical bond vibration of biomolecules can influence neuronal function remains unknown. We found that midinfrared light with low water absorption provides nonthermal and reversible modulation of neuronal spiking activity and sensorimotor behavior. Nonlinear resonance between light and chemical bond vibration at the selectivity sieve of the K + channel directly enhances ion conductivity and thus regulates AP waveform and spiking activity. Together, our results reveal nonthermal effects of MIRS on functional biomolecules, neuronal signaling, and behavior state. Therefore, MIRS could serve as a form of physical neuromodulation.