Abstract Background We observed that a dim. red light-emitting diode (LED) triggered by activity increased the circadian periods of lab mice compared to constant darkness. It is known that the circadian period of rats increases when vigorous wheel-running triggers full-spectrum lighting; however. spectral sensitivity of photoreceptors in mice suggests little or no response to red light. https://www.ealisboa.com/limited-price-Cable-Splitter-weBoost-WilsonPro-by-Wilson-Electronics-mega-offer/