Motivation and emotion/Book/2026/Melatonin and seasonal mood

Melatonin and seasonal mood:
What role does melatonin play in seasonal mood changes?

Overview

Figure 1. Use a captioned image to illustrate the scenario Case study Seasonal levels of melatonin near the Arctic Circle Through explorations of the Arctic circle and the effects on mood and cognitive performance has on explorers, a study was conducted on why this would be the case. Circumpolar environments have been known for its changes in day night cycles as well as its temperature. Explorers within these research stations have reported increases in depressive symptoms. There was a hypothesis on being a link between melatonin production and the effects of the Arctic's seasonal characteristics. Especially the link of the light intensity and its suppression in producing melatonin.

The Overview section should provide:

1. Scenario: A short, engaging case study or real-world example in a feature box, with an accompanying image (see above)
2. Explanation of the problem, issue, or topic: Briefly explain the problem, why it is important, and outline how psychological science can help
3. Focus questions: Unpack the sub-title into focus questions in a feature box

Recommended length: 180 to 330 words.

Focus questions Break the sub-title down into three to five focus questions. Align the top-level headings with these focus questions. How is Melatonin produced? What seasonal effects have been shown on mood? Does irregular melatonin production have an impact on Seasonal Mood Disorders and if so why? Ask open-ended focus questions. For example: Is there a relationship between weather and criminal behaviour? (closed-ended) What is the relationship between weather and criminal behaviour? (open-ended)

Melatonin

Figure 1. Melatonin Chemical Structure

Melatonin is a hormone, best know through its function of regulating circadian rhythms. (Megha, et al, 2024)

• Indolamines, a family of neurotransmitters, that share a common molecular structure
• Produced in the Pineal Gland
  • For vertabres melatonin is produced in the dark
  • Melatonin is a key signaling molecule that connects changes in external light conditions with changes
    • After the retina receives a light signal, it transmits the signal to the pineal gland which then transforms the light signal into melatonin.
• Circulars through the blood stream
• Various tissues and oragans can secrete melatonin
  • but only the reinal tissue of the pineal glad and eyes show periodic secretory activity
  • linking the biosysynthesis of melatonin shows that circidian rhythm and seasonal characteristics associated with external light conditions
  • Meliska et al (2013)

Functions

• Sleep (regulates circadian changes)
• linked with light
• proctective effects on the nervous system
• Broad spectrum and antibacterial and immunoregularory functions
• Even looking into melatonin's relations with fertility and reproduction

Melatonin Synthesis and secretion

Figure 2. Mechanism of melatonin biosynthesis

• tryptohan excreted from the small instestine into the blood circulation and actively taken up by pineal cells
• AANAT converts the tryptohan hydroxlase into ASMT
• catalyzes into melatonin
• cAMP-catalyzed proteins promotates formation of a complex
• reduces the K (m) of serotonin, enhancing melatonin production
• Melatonin is released into the blood and spinal fluid
• blinds into plasma proteins
• Distructed throughout most tissues

Figure 3. Melatonin production in 24 hour cycle

Melatonin Fluctuations/Imbalance

• Melatonin release cycles over time
• Temperature
• Circandian cycle and daylight changes

1. Melatonin is produced by the?

	Pineal Gland
	Cerebral Cortex
	Brain Stem
	Retina

Seasonal Mood Disorders

Seasonal Affective Disorder (SAD)

• Part of the depression and bipolar family
• Combination of biological and mood disturbances through out different seasonal patterns
  • Most commonly occurring during autumn and winter but cases have shown in the other seasons too ( Kurlanksik & Ibay, 2012)
• Light therapy has been shown to be effective for most patients showing clinical improvements within one to two weeks after the start of treatment ( Kurlanksik & Ibay, 2012)

Studies

• Artic Study on melatonin and light
• Effect on controlled-release melatonin on sleep quality, mood and quality of life in subjects with seasonal or weather-associated changes in mood and behaviour (2003)
  • Double-blind trial
    • Group A Melatonin
    • Group B placebo
  • Connected with the photoperiod not the weather-related aspect of the seasons

Key points

For the topic development, for each heading and sub-heading:

• Provide at least three bullet-points, including for the Overview and Conclusion
• Include key citations

Quizzes

• Using one or two quiz questions for each main section is better than a long quiz at the end
• Quiz conceptual understanding, rather than trivia. Ask about important information such as take-home messages
• Ask easy rather than hard questions
• Different types of quiz questions are possible; see Quiz

Example simple quiz questions. Choose your answers and click "Submit":

1

The purpose of quizzes is to provide an interactive learning feature:

	True
	False

2

Long and complex quiz questions are recommended:

	True
	False

Conclusion

• The Conclusion is arguably the most important section
• Draft clear take-home message(s), even at the topic development stage
• Together, the Overview and Conclusion should summarise the problem, its significance, and how psychological science contributes to understanding and addressing it
• Recommended length: 150 to 330 words

Suggestions for this section: What is the answer to the sub-title question based on psychological theory and research? What are the answers to the focus questions? What are the practical, take-home messages?

See also

Provide internal (wiki) links to the most relevant Wikiversity pages (esp. related motivation and emotion book chapters) and Wikipedia articles. Use sentence casing and alphabetical order. For example:

• Melatonin (Wikipedia)
• Light triad (Book chapter, 2021)
• Self determination theory (Wikipedia)

Suggestions for this section: Only select links to major internal resources about the topic Include the source in parentheses

References

This section lists the cited references in APA style (7th ed.) or wiki style.

APA style example:

Kurlansik, Stuart & Ibay, Annamarie. (2012). Seasonal affective disorder. American family physician. 86. 1037-41.

Megha, K.B., Arathi, A., Shikha, S. et al. Significance of Melatonin in the Regulation of Circadian Rhythms and Disease Management. Mol Neurobiol 61, 5541–5571 (2024). https://doi.org/10.1007/s12035-024-03915-0

Meliska, C. J., Martínez, L. F., López, A. M., Sorenson, D. L., Nowakowski, S., Kripke, D. F., Elliott, J., & Parry, B. L. (2013). Antepartum depression severity is increased during seasonally longer nights: relationship to melatonin and cortisol timing and quantity. Chronobiology international, 30(9), 1160–1173. https://doi.org/10.3109/07420528.2013.808652

Pääkkönen,T., Leppäluoto, J., Ikäheimo, T., & Rintamäki, H., Ruokonen, A., Hassi, J., & Palinkas, L., (2008). Seasonal Levels of Melatonin, Thyroid Hormones, Mood, and Cognition Near the Arctic Circle. Aviation, space, and environmental medicine. 79. 695-9. https://doi.org/10.3357/ASEM.2148.2008.

Suggestions for this section: Wrap the set of references in the hanging indent template: Use "Edit source" {{Hanging indent|1= the full list of references}} Important aspects of APA referencing style Author surname, followed by a comma, then the author initials separated by full stops and spaces Year of publication in parentheses Title of work in lower case (except first letter and proper names), ending in a full-stop Journal title in italics, volume number in italics, issue number in parentheses, first and last page numbers separated by an en-dash(–), followed by a full-stop doi as a URL which is a working hyperlink (i.e., clickable) The most common mistakes include: Incorrect capitalisation Incorrect italicisation dois which aren't clickable as working hyperlinks Citing sources that haven't been consulted

External links

Provide external links to highly relevant resources such as podcasts and videos, news articles, and professional sites. Use sentence casing and alphabetical order. For example:

• Six top tips for writing a great essay (University of Melbourne)
• The importance of structure (skillsyouneed.com)
• Antepartum Depression Severity is Increased During Seasonally Longer Nights: Relationship to Melatonin and Cortisol Timing and Quantity
• Effect of controlled-release melatonin on sleep quality, mood, and quality of life in subjects with seasonal or weather-associated changes in mood and behaviour
• Seasonal levels of melatonin, thyroid hormones, mood, and cognition near the Arctic Circle
• Melatonin as a treatment for mood disorders: a systematic review
• Melatonin and agomelatine for preventing seasonal affective disorder
• Seasonal rhythms in mental health: a narrative scoping review of neurobiological mechanisms and therapeutic interventions  
• Melatonin Biosynthesis and regulation in reproduction
• Seasonal changes in mood and behavior: A cluster analytic approach https://www.sciencedirect.com/science/article/abs/pii/0165178189900498
• Ngiam, Alicia. (2022). Light Deprivation and Its Effects. https://www.researchgate.net/publication/365021664_Light_Deprivation_and_Its_Effects

Suggestions for this section: Only select links to major external resources about the topic Include the source in parentheses after the link