We are far from knowing the limits of light therapy, or the involvement of circadian timing in mental and physical illness. New exploratory applications give a sense of the broad range of possibilities, although the research needs extensive follow-up before we endorse or codify the intervention as a mainline strategy, or alternative to established medication regimens.

Exciting examples in the pipeline including light therapy for the cognitive and motor disabilities of Parkinson’s disease; the cognitive and sleep problems of attention deficit hyperactivity disorder; rebalancing and stimulating sex hormone production in both men  and women; counteracting the extreme fatigue associated with chemotherapy; and improving sleep and wellbeing in patients with personality disorders.

REFERENCES

Reviews

Terman M. Evolving applications of light therapy. Sleep Medicine Reviews, 2007;11:497-507.

Studies

Yoon I-Y, Kripke DF, Elliott JA, Youngstedt S. Luteinizing hormone following light exposure in healthy young men. Neurosci Lett 2003;341:25-28.
Rybak YE, McNeely HE, Mackenzie BE, Jain UR, Levitan RD. An open trial of light therapy in adult attention-deficit/hyperactivity disorder. Journal of Clinicial Psychiatry  2006;67:1527-1535.
Willis GL, Turner EJ. Primary and secondary features of Parkinson’s disease improve with strategic exposure to bright light: a case series study. Chronobiol International 2007;24:521-537.
Danilenko KV, Samoilova EA. Stimulatory effect of morning bright light on reproductive hormones and ovulation: results of a controlled crossover trial. PLoS Clinical Trials 2007;2:e7.
Ancoli-Israel S, Rissling M, Neikrug A, Trofimenko V, Natarajan L, Parker BA, Lawton S, Desan P, Liu L. Light treatment prevents fatigue in women undergoing chemotherapy for breast cancer. Supportive Care in Cancer 2012;20:1211-1219.
Bromundt V, Wirz-Justice A, Kyburz S, Opwis K, Dammann G, Cajochen C. Circadian sleep-wake cycles, well-being, and light therapy in borderline personality disorder. Journal of Personality Disorders 2013;27:680-96.
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