Review of Transcranial Photobiomodulation for Major Depressive Disorder: Targeting Brain Metabolism, Inflammation, Oxidative Stress, and Neurogenesis

This review examines the potential of transcranial photobiomodulation (tPBM) using red and near-infrared light as a treatment for major depressive disorder (MDD). The authors discuss how PBM may influence brain function by targeting biological pathways involved in depression, including impaired metabolism, inflammation, oxidative stress, and reduced neurogenesis.

The article explains that tPBM works by penetrating scalp and skull tissues to stimulate mitochondrial activity, particularly cytochrome c oxidase, which may increase ATP production, improve cerebral blood flow, regulate oxidative stress, and support neuronal repair and survival. These effects could help improve brain function and mood-related pathways.

The review highlights early evidence suggesting that tPBM may reduce depressive symptoms, improve cognition, and provide neuroprotective benefits. However, the authors note that while results are promising, larger controlled clinical trials are needed to confirm long-term safety, efficacy, and standardized treatment protocols.

Key takeaway: Transcranial PBM shows promise as a non-invasive therapy for depression by targeting brain metabolism, inflammation, and neurogenesis, but stronger clinical evidence is still needed before widespread adoption.