Related Experiment Video
Updated: Jul 12, 2025
08:36
Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments
Published on: August 8, 2019
12.0K
Mood correlates with circadian alignment in healthy individuals
Jonathan S Emens1, Alfred J Lewy2
1Department of Psychiatry, Oregon Health & Science University, Portland, Oregon, USA; Oregon Institute of Occupational Health Sciences, Portland, Oregon, USA; Division of Mental Health, VA Portland Health Care System, Portland, Oregon, USA.
Sleep Health
|November 1, 2023
Summary
Later sleep timing relative to your internal body clock is linked to poorer mood in healthy adults. This study highlights the connection between circadian alignment and emotional well-being.
Area of Science:
- Chronobiology
- Sleep Medicine
- Psychiatry
Background:
- Circadian rhythms regulate physiological processes, including sleep-wake cycles.
- Disruptions in circadian alignment are implicated in mood disorders.
- Understanding this relationship in healthy individuals is crucial for preventative strategies.
Purpose of the Study:
- To investigate the correlation between mood and circadian phase alignment in healthy individuals.
- To assess if the timing of the internal body clock (circadian pacemaker) influences mood.
- To examine the relationship between sleep timing and mood in euthymic adults.
Main Methods:
- 25 healthy first-year medical students participated.
- Mood was assessed using the Profile of Mood States (POMS) brief form.
- Circadian phase was measured via salivary dim light melatonin onset (DLMO).
- Circadian alignment was quantified by the DLMO to average midsleep interval (phase angle difference).
Main Results:
- A significant correlation was found between phase angle difference and mood.
- Later DLMO relative to midsleep (shorter phase angle differences) was associated with worse mood.
- No significant gender differences in mood or interaction with circadian alignment were observed.
Conclusions:
- Circadian alignment is correlated with mood in healthy individuals.
- These findings align with observations in individuals with depression.
- The results suggest implications for mood disorder prevention and treatment development.
Related Concept Videos
02:19Circadian Rhythms and Gene Regulation
4.1K
The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent...
4.1K
01:15Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response
69
Circadian rhythms are cyclic changes that are crucial in plasma drug concentrations. Various standard circadian parameters, including core body temperature, heart rate, and other cardiovascular factors, directly impact disease states and the therapeutic response to drug therapy.
The time of drug administration is an important factor to consider, as it can influence the toxic dose of a drug. For example, a study conducted by Prins et al. in 1997 examined the effects of the timing of...
The time of drug administration is an important factor to consider, as it can influence the toxic dose of a drug. For example, a study conducted by Prins et al. in 1997 examined the effects of the timing of...
69
01:53Cause and Effect
10.9K
While variables are sometimes correlated because one does cause the other, it could also be that some other factor, a confounding variable, is actually causing the systematic movement in our variables of interest. For instance, as sales in ice cream increase, so does the overall rate of crime. Is it possible that indulging in your favorite flavor of ice cream could send you on a crime spree? Or, after committing crime do you think you might decide to treat yourself to a cone?
10.9K
02:20Correlations
32.8K
Correlation means that there is a relationship between two or more variables (such as ice cream consumption and crime), but this relationship does not necessarily imply cause and effect. When two variables are correlated, it simply means that as one variable changes, so does the other. We can measure correlation by calculating a statistic known as a correlation coefficient. A correlation coefficient is a number from -1 to +1 that indicates the strength and direction of the relationship between...
32.8K
01:11Understanding Sleep
236
Sleep, an essential biological state, involves significant reductions in physical activity, sensory awareness, and interaction with the environment. This complex physiological process is primarily regulated by specific brain regions, notably the hypothalamus and pons, which govern the sleep-wake cycle or circadian rhythm.
The circadian rhythm, a nearly 24-hour cycle, is deeply influenced by environmental light cues. Light exposure directly affects the hypothalamus, which in turn regulates...
The circadian rhythm, a nearly 24-hour cycle, is deeply influenced by environmental light cues. Light exposure directly affects the hypothalamus, which in turn regulates...
236
01:19Management of Insomnia
259
The sleep cycle, an integral part of human health, consists of several stages with distinct characteristics and functions. It begins with a transition from wakefulness to sleep, known as the light sleep phase, followed by the restorative deep sleep phase, essential for physical recovery and growth. The cycle concludes with the Rapid Eye Movement (REM) phase, characterized by high brain activity and vivid dreaming. Insomnia, a prevalent sleep disorder, involves difficulty falling asleep, staying...
259