In 2025, Qin Yang and team conducted a randomized, single-blind, crossover trial with 55 healthy older adults to explore transcranial photobiomodulation (tPBM), a form of red light therapy using a 1064-nm laser on the left forehead. Using fNIRS, they measured brain connectivity and assessed working memory via the 3-back task before and after active or sham tPBM sessions.