1The Brain Cognition and Brain Disease Institute for Collaborative Research of SIAT at CAS and the McGovern Institute at MIT, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
2McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA

Abstract 

Observations from clinical trials have frequently demonstrated that light therapy can be an effective therapy for seasonal and non-seasonal major depression. Despite the fact that light therapy is known to have several advantages over antidepressant drugs like a low cost, minimal side-effects, and fast onset of therapeutic effect, the mechanism underlying light therapy remains unclear. So far, it is known that light therapy modulates mood states and cognitive functions, involving circadian and non-circadian pathways from retinas into brain. In this review, we discuss the therapeutic effect of light on major depression and its relationship to direct retinal projections in the brain. We finally emphasize the function of the retino-raphe projection in modulating serotonin activity, which probably underlies the antidepressant effect of light therapy for depression.

Keywords

Light therapy, Depression, Retinal projection, Serotonin, Opsin

[SpringerLink]