BRIGHT LIGHT THERAPY IN SELECTED NEUROPSYCHIATRIC AND SLEEP-RELATED CONDITIONS: A NARRATIVE REVIEW
DOI:
https://doi.org/10.31435/ijitss.1(49).2026.5691Keywords:
Bright Light Therapy, Seasonal Affective Disorder, Major Depressive Disorder, Bipolar Depression, Shift Work, Parkinson’s Disease, Circadian Rhythm, Sleep MedicineAbstract
Bright light therapy (BLT), defined as timed exposure to high-intensity light, is an established nonpharmacological treatment for seasonal affective disorder (SAD) and is increasingly being investigated in other areas of neuropsychiatry and sleep medicine. This narrative review synthesizes evidence published between 2015 and 2025 on the clinical applications of BLT in SAD, non-seasonal major depressive disorder, bipolar depression, shift-work-related circadian misalignment, sleep and selected non-motor symptoms of Parkinson’s disease. Relevant English-language literature was identified through PubMed and Google Scholar, with emphasis on systematic reviews, meta-analyses and randomized controlled trials. The strongest evidence supports BLT in winter-pattern SAD, where it remains first-line acute treatment associated with clinically meaningful symptom improvement. In non-seasonal major depressive disorder, pooled findings indicate a small-to-moderate antidepressant effect, although outcomes are more heterogeneous and seem to be influenced by treatment timing, chronotype and ambient light exposure. In bipolar depression, adjunctive BLT administered under mood-stabilizer coverage shows benefit and is generally well tolerated, with low short-term rates of manic or hypomanic switching when conservative protocols are used. In shift-work-related circadian disruption, BLT is associated with modest sleep benefits and measurable circadian phase delay, supporting its use as a strategy for circadian adaptation. In Parkinson’s disease, available studies suggest benefit for sleep disturbance and excessive daytime sleepiness, whereas effects on mood and other non-motor symptoms remain less consistent. Overall, BLT appears to be a clinically meaningful and feasible intervention across multiple conditions, although broader implementation is limited by protocol heterogeneity, biologically active control-light designs and limited long-term follow-up.
References
Campbell, P. D., Miller, A. M., & Woesner, M. E. (2017). Bright light therapy: Seasonal affective disorder and beyond. Einstein Journal of Biology and Medicine, 32, E13–E25.
Meyerhoff, J., Young, M. A., & Rohan, K. J. (2018). Patterns of depressive symptom remission during the treatment of seasonal affective disorder with cognitive-behavioral therapy or light therapy. Depression and Anxiety, 35(5), 457–467. https://doi.org/10.1002/da.22739
Al-Karawi, D., & Jubair, L. (2016). Bright light therapy for nonseasonal depression: Meta-analysis of clinical trials. Journal of Affective Disorders, 198, 64–71. https://doi.org/10.1016/j.jad.2016.03.016
Perera, S., Eisen, R., Bhatt, M., Bhatnagar, N., de Souza, R., Thabane, L., & Samaan, Z. (2016). Light therapy for non-seasonal depression: Systematic review and meta-analysis. BJPsych Open, 2(2), 116–126. https://doi.org/10.1192/bjpo.bp.115.001610
Videnovic, A., Klerman, E. B., Wang, W., Marconi, A., Kuhta, T., & Zee, P. C. (2017). Timed light therapy for sleep and daytime sleepiness associated with Parkinson disease: A randomized clinical trial. JAMA Neurology, 74(4), 411–418. https://doi.org/10.1001/jamaneurol.2016.5192
Raymackers, J. M., Andrade, M., Baey, E., Vanneste, M., & Evrard, F. (2019). Bright light therapy with a head-mounted device for anxiety, depression, sleepiness and fatigue in patients with Parkinson’s disease. Acta Neurologica Belgica, 119(4), 607–613. https://doi.org/10.1007/s13760-019-01214-3
Endo, T., Matsumura, R., Tokuda, I. T., Yoshikawa, T., Shigeyoshi, Y., Node, K., Sakoda, S., & Akashi, M. (2020). Bright light improves sleep in patients with Parkinson’s disease: Possible role of circadian restoration. Scientific Reports, 10(1), Article 7982. https://doi.org/10.1038/s41598-020-64645-6
Xie, W. Y., Lou, H., Liu, J. Y., Yin, J. Y., Zhang, T. Q., Mao, C. J., Wang, F., Liu, C. F., & Shen, Y. (2025). Bright light therapy in Parkinson’s disease: A pilot study on visual pathway improvements. BMC Psychiatry, 25(1), Article 476. https://doi.org/10.1186/s12888-025-06915-z
van Maanen, A., Meijer, A. M., van der Heijden, K. B., & Oort, F. J. (2016). The effects of light therapy on sleep problems: A systematic review and meta-analysis. Sleep Medicine Reviews, 52–62. https://doi.org/10.1016/j.smrv.2015.08.009
Lam, R. W., Teng, M. Y., Jung, Y. E., Evans, V. C., Gottlieb, J. F., Chakrabarty, T., Michalak, E. E., Murphy, J. K., Yatham, L. N., & Sit, D. K. (2020). Light therapy for patients with bipolar depression: Systematic review and meta-analysis of randomized controlled trials. The Canadian Journal of Psychiatry, 65(5), 290–300. https://doi.org/10.1177/0706743719892471
Sun, W., Yan, J., Wu, J., & Ma, H. (2022). Efficacy and safety of light therapy as a home treatment for motor and non-motor symptoms of Parkinson disease: A meta-analysis. Medical Science Monitor, 28, e935074. https://doi.org/10.12659/MSM.935074
Chen, Z. W., Zhang, X. F., & Tu, Z. M. (2024). Treatment measures for seasonal affective disorder: A network meta-analysis. Journal of Affective Disorders, 350, 531–536. https://doi.org/10.1016/j.jad.2024.01.028
Sit, D. K., McGowan, J., Wiltrout, C., Diler, R. S., Dills, J. J., Luther, J., Yang, A., Ciolino, J. D., Seltman, H., Wisniewski, S. R., Terman, M., & Wisner, K. L. (2018). Adjunctive bright light therapy for bipolar depression: A randomized double-blind placebo-controlled trial. The American Journal of Psychiatry, 175(2), 131–139. https://doi.org/10.1176/appi.ajp.2017.16101200
Hirakawa, H., Terao, T., Muronaga, M., & Ishii, N. (2020). Adjunctive bright light therapy for treating bipolar depression: A systematic review and meta-analysis of randomized controlled trials. Brain and Behavior, 10(12), e01876. https://doi.org/10.1002/brb3.1876
Zhao, C., Li, N., Miao, W., He, Y., & Lin, Y. (2025). A systematic review and meta-analysis on light therapy for sleep disorders in shift workers. Scientific Reports, 15(1), Article 134. https://doi.org/10.1038/s41598-024-83789-3
Rohan, K. J., Mahon, J. N., Evans, M., Ho, S.-Y., Meyerhoff, J., Postolache, T. T., & Vacek, P. M. (2015). Randomized trial of cognitive-behavioral therapy vs. light therapy for seasonal affective disorder: Acute outcomes. The American Journal of Psychiatry, 172(9), 862–869. https://doi.org/10.1176/appi.ajp.2015.14101293
Pjrek, E., Friedrich, M. E., Cambioli, L., Dold, M., Jäger, F., Komorowski, A., Lanzenberger, R., Kasper, S., & Winkler, D. (2020). The efficacy of light therapy in the treatment of seasonal affective disorder: A meta-analysis of randomized controlled trials. Psychotherapy and Psychosomatics, 89(1), 17–24. https://doi.org/10.1159/000502891
Wan, Y., Ding, J., Fan, M., & Huang, H. (2025). Effectiveness of visible light for seasonal affective disorder: A systematic review and network meta-analysis. Medicine, 104(27), e43107. https://doi.org/10.1097/MD.0000000000043107
Menegaz de Almeida, A., Aquino de Moraes, F. C., Cavalcanti Souza, M. E., Cavalcanti Orestes Cardoso, J. H., Tamashiro, F., Miranda, C., Fernandes, L., Kreuz, M., & Alves Kelly, F. (2025). Bright light therapy for nonseasonal depressive disorders: A systematic review and meta-analysis. JAMA Psychiatry, 82(1), 38–46. https://doi.org/10.1001/jamapsychiatry.2024.2871
Chen, I. P., Huang, C. C., Huang, H. C., Yang, F. G., Ko, K. T., Lee, Y. T., Sun, F. J., & Liu, S. I. (2022). Adjunctive bright light therapy for non-seasonal major depressive disorder: A randomized controlled trial. International Journal of Environmental Research and Public Health, 19(19), Article 12430. https://doi.org/10.3390/ijerph191912430
Chan, J. W., Lam, S. P., Li, S. X., Chau, S. W., Chan, S. Y., Chan, N. Y., Zhang, J. H., & Wing, Y. K. (2022). Adjunctive bright light treatment with gradual advance in unipolar major depressive disorder with evening chronotype: A randomized controlled trial. Psychological Medicine, 52(8), 1448–1457. https://doi.org/10.1017/S0033291720003232
Wang, S., Zhang, Z., Yao, L., Ding, N., Jiang, L., & Wu, Y. (2020). Bright light therapy in the treatment of patients with bipolar disorder: A systematic review and meta-analysis. PLOS ONE, 15(5), e0232798. https://doi.org/10.1371/journal.pone.0232798
Yorguner Kupeli, N., Bulut, N. S., Carkaxhiu Bulut, G., Kurt, E., & Kora, K. (2018). Efficacy of bright light therapy in bipolar depression. Psychiatry Research, 260, 432–438. https://doi.org/10.1016/j.psychres.2017.12.020
Lam, C., & Chung, M. H. (2021). Dose-response effects of light therapy on sleepiness and circadian phase shift in shift workers: A meta-analysis and moderator analysis. Scientific Reports, 11(1), Article 11976. https://doi.org/10.1038/s41598-021-89321-1
Rutten, S., Vriend, C., Smit, J. H., Berendse, H. W., van Someren, E. J. W., Hoogendoorn, A. W., Twisk, J. W. R., van der Werf, Y. D., & van den Heuvel, O. A. (2019). Bright light therapy for depression in Parkinson disease: A randomized controlled trial. Neurology, 92(11), e1145–e1156. https://doi.org/10.1212/WNL.0000000000007090
Lin, F., Su, Y., Weng, Y., Lin, X., Weng, H., Cai, G., & Cai, G. (2021). The effects of bright light therapy on depression and sleep disturbances in patients with Parkinson’s disease: A systematic review and meta-analysis of randomized controlled trials. Sleep Medicine, 83, 280–289. https://doi.org/10.1016/j.sleep.2021.03.035
Tao, L., Jiang, R., Zhang, K., Qian, Z., Chen, P., Lv, Y., & Yao, Y. (2020). Light therapy in non-seasonal depression: An updated meta-analysis. Psychiatry Research, 291, 113247. https://doi.org/10.1016/j.psychres.2020.113247
Downloads
Published
Issue
Section
License
Copyright (c) 2026 Hanna Maruchniak, Wiktoria Marzec, Paulina Biedroń, Anna Skrzypek, Maciej Hutkowski, Mikołaj Zbrożek, Zuzanna Chwostek, Bartłomiej Kosiarski, Patrycja Markowicz, Krzysztof Biłyk
This work is licensed under a Creative Commons Attribution 4.0 International License.
All articles are published in open-access and licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0). Hence, authors retain copyright to the content of the articles.
CC BY 4.0 License allows content to be copied, adapted, displayed, distributed, re-published or otherwise re-used for any purpose including for adaptation and commercial use provided the content is attributed.
How to Cite
