Effects of far-infrared radiation on the nervous system and their potential

Far-infrared radiation (FIR; 3-1000 μm) is characterized by its strong tissue penetration and efficient heat conduction properties. Specifically, wavelengths within the range of 8-14 μm-often referred to as growth rays-are efficiently absorbed by living organisms, generating pronounced thermal effects. These wavelengths closely correspond to the natural vibrational wavelength of water molecules, thus enabling effective resonance and energy absorption. This property has led to their widespread use as a therapeutic tool in biomedical and healthcare applications. Because living organisms contain a substantial proportion of water, FIR can penetrate deeply into tissue, influencing various molecules through resonance with water molecules and modulating molecular mechanisms, thereby eliciting a range of physiological effects. The effects of FIR have been examined across diverse disciplines. The present review focuses on the effects of FIR on the nervous system. It compiles and discusses findings from previous studies that have used animal models of nervous system diseases to explore the direct effects of FIR on various aspects of the nervous system, including memory impairment, cognitive function, neural regeneration, sleep, anti-inflammatory effects, and stress relief.