TAIPEI (Taiwan News) — A wearable light therapy device can significantly improve sleep in people with major depressive disorder, Tainan Municipal An-Nan Hospital announced Thursday.

Sleep problems are common and difficult to treat in depression. A recent study found that participants who received transcranial photobiomodulation (tPBM) therapy showed notable improvements in their Pittsburgh Sleep Quality Index scores, suggesting that better sleep may support overall recovery, per CNA.

The study is among the few double-blind, randomized clinical trials worldwide testing wearable tPBM in patients with major depressive disorder. This noninvasive therapy uses near-infrared light to stimulate cellular activity in the brain and treat various conditions, including Alzheimer’s and Parkinson’s disease, brain injuries, stroke, and psychiatric disorders, according to a study published in the US National Library of Medicine.

The device, a head-mounted unit developed by an international research team including Taiwan’s China Medical University Beigang Hospital, Harvard Medical School, and Massachusetts General Hospital, delivers 850-nanometer near-infrared LED light to the front part of the brain. Each session lasts 20 to 40 minutes and can be done once or twice daily.

Participants began noticing improvements in sleep by the second week of treatment, with benefits lasting up to four weeks after therapy ended. To ensure compatibility, the trial also included 12 elderly participants over 65 and three dialysis patients.

The device’s design allows patients to use it safely at home, either independently or with help from family members. Only minor discomfort was reported, and adherence to the treatment plan was high.

Deputy Superintendent Su Kuan-pin (蘇冠賓) said the study represents progress in making mental health care more personalized and accessible. It has been published in the international Journal of Affective Disorders.