When we think about sleep, a few questions and thoughts generally run through our brains (sometimes, ironically, at 2 AM when we should be soundly sleeping). Why do we need sleep? How does sleep benefit our health? What parts of the brain are involved in sleep, and how does it all really work, like scientifically?

The science of sleep might seem weird or complex, so we’re here to break it down for you and cut through a lot of the white noise. At Ritual, we value sleep as an essential pillar of health, not just a nice-to-have or bonus. In fact, we think it’s so important that we even formulated our own very own sleep supplement. Sleep BioSeries™ Melatonin is designed to be released in phases throughout the night to support falling asleep and staying asleep.* But in order to take even better care of your sleep habits, we’re here to pull back the sheets on how this elusive process actually functions.

Why Do We Need Sleep?

There is more to sleep than the hours we spend in bed. It’s about how we sleep, the quality we are getting, and the consistency of restful and rejuvenating slumbers.

While we sleep, our body is ramping up all functions of TLC. Meaning that during those blissful hours, our systems are cleansing, repairing, and preparing our bodies for continued healing. Certain body processes do most of their work while we are asleep; if we skimp on it or don’t strive for quality sleep, those systems are not able to fully do their jobs. The result of that is feeling groggy upon waking, being fatigued and sluggish during the height of the day, unable to concentrate and perhaps feeling irritable, having frequent cravings for sweet and/or salty foods. Not prioritizing sleep or beneficial sleep hygiene have both short and long term impacts on our health. To understand the science of sleep, we’ll first dive into the “anatomy of sleep”, what parts of the brain are involved and how this blissful ritual works.

Your Brain On Sleep: The Anatomy of a Good Night’s Rest

The anatomy of sleep is quite remarkable. While the act of sleeping might seem like a no-brainer, there are so many powerful and intricate players involved in getting the stars to align. Outside of just picking out the right firmness of the mattress, there are 9 parts of the brain that work synergistically in order to make sleep work. (4)

1. Hypothalamus: Deep inside the brain are clusters of nerve cells that make up a structure called the hypothalamus. The hypothalamus acts as the main control center responsible for sleep.

2. Suprachiasmatic Nucleus (or SCN): Within the hypothalamus is a group of thousands of cells called the suprachiasmatic nucleus. The SCN receives information directly from the eyes about light exposure and determines the behavioral changes involved with staying awake or going to sleep.

3. Pineal Gland: The brain has two hemispheres and within them is a gland called the pineal gland. The pineal gland receives information about light exposure from the SCN. If the SCN is telling the pineal gland that light exposure has come down, meaning either the sun has gone down or artificial light exposure has turned off, it begins the production of a hormone called melatonin. Melatonin is also incredibly sensitive to light exposure.

4. Brain Stem: Located at the base or bottom of the brain, the brain stem communicates with the hypothalamus. The brain stem is responsible for controlling the transition between being awake and being asleep, playing a unique role during REM sleep. In fact, the brain stem sends signals to our muscles and limbs to relax fully, so we are not flinging our arms and legs around while we are asleep and dreaming.

5. Thalamus: Speaking of dreaming, two parts of the brain are responsible for creating the visions and sensations felt in dreams. During non-REM stages of sleep, the thalamus quiets down and takes in less information both from the external world and the cerebral cortex.

6. Cerebral Cortex: The covering of the brain that interprets information and memory. Meaning any noise happening while you are asleep, the thalamus consciously quiets down so we can stay in the deepest phase of sleep. Though when we enter REM sleep, the thalamus is active and it begins to receive and send sensations including imagery, sounds and memory to help create our dreams. That’s why we sometimes see people we know in our dreams (yes, including that ex you swore you’d never think about again) or have dreams take place in places we have visited before.

7. Basal Forebrain: Located near the front and bottom of the brain, the basal forebrain also helps to promote sleep and wakefulness.

8. Midbrain: Where the brain and spinal cord meet is the topmost part of the brain stem called the midbrain. (5) The midbrain has actually been shown to be able to detect stress and induce or encourage restorative sleep. (6)

9. Amygdala: A lack of restorative and quality sleep puts the amygdala in stress. The amygdala is responsible for processing emotions, so less sleep equals irritability, exhaustion and inconsistencies with mood. (7)

The Roles that Genes and Hormones Play in Sleep

We keep coming back to the role of light exposure, so let’s rewind and understand why light matters both for how sleep works and the overall science of sleep.

We as humans are cyclical beings, meaning that since the earliest of times, our bodies and systems operate on a specific cycle. This cycle is governed by light exposure, primarily sunlight and moonlight. The modern day exposure of artificial light has disrupted our body’s natural cycle and as a result, impacts the quality of sleep.

The cycle or clock mentioned is called the circadian rhythm, which operates on a 24 hour cycle. The circadian rhythm regulates sleep, controls when we feel tired or when we feel awake. The natural circadian rhythm cycle starts highest in the morning and as the day progresses it begins to taper down, resulting in feeling more tired as the hours pass and ultimately ready to sleep at night. There are different hormones or chemical messengers that regulate this cycle, we’ll explore three of the most commonly known ones.

• Cortisol: As we are exposed to more light throughout the day, starting with the sun rising, our bodies release cortisol. Cortisol is what helps our bodies wake up and feel alert in the mornings. Cortisol naturally begins to decline throughout the day, while other hormones begin to rise preparing us for sleep.

• Adenosine: As cortisol levels taper down, adenosine levels begin to rise. This rise signals the brain and our bodies towards sleep. As we are asleep, the body breaks down adenosine so that cortisol can slowly begin to rise and help us wake. (8)

• Melatonin: Similar to adenosine, melatonin sees its peak towards the end of the day, after the sun has set and natural light disappears. As mentioned earlier, melatonin is very sensitive to light; which is why exposure to even artificial light in the later part of the evening can disrupt the process of melatonin release.

Genes play a significant role in influencing various aspects of sleep including the timing, duration and quality of sleep. Some genes, also known as “clock genes,” influence the circadian rhythm and the timing of sleep. (4) These genes can also influence the pattern of sleep, including both non-REM and REM sleep cycles and regulate melatonin production. The pineal gland and clock genes work together to synchronize between light conditions and the circadian rhythm.

Sleep is sacred and the ‘ritual’ of it should be prioritized. That first comes with understanding the science of sleep, how sleep works and why we need sleep at all. When we are equipped with this information, we’re able to not only make sound decisions that benefit our health, but we are able to understand the importance of certain behaviors such as sleep.

At Ritual, we certainly recognize the importance of sleep and the science behind it. So we put science and slumber in sync with our BioSeries™ Melatonin. BioSeries™ technology combines 5mg of instant and extended release Melatonin designed with the body’s Melatonin release in mind. Our three-in-one tablet in capsule ,melatonin releases in phases to support falling asleep and staying asleep to wake up rested.*

References:

1. National Heart, Lung, and Blood Institute. How sleep works - Why is sleep important? www.nhlbi.nih.gov. Published March 24, 2022.

2. National Heart, Lung, and Blood Institute. How Sleep Works - Sleep Phases and Stages | NHLBI, NIH. www.nhlbi.nih.gov. Published March 24, 2022.

3. How Sleep Works - Your Sleep/Wake Cycle | NHLBI, NIH. www.nhlbi.nih.gov.

4. Brain Basics: Understanding Sleep. National Institute …. Accessed October 9, 2023.

5. The midbrain. qbi.uq.edu.au. Published November 14, 2017.

6. Yu X, Zhao G, Wang D, et al. A specific circuit in the midbrain detects stress and induces restorative sleep. Science (New York, NY). 2022;377(6601):63-72.

7. Saghir Z, Syeda JN, Muhammad AS, Balla Abdalla TH. The Amygdala, Sleep Debt, Sleep Deprivation, and the Emotion of Anger: A Possible Connection? Cureus. 2018;10(7).

8. Pacheco D. Why do we need sleep? Sleep Foundation. Published August 10, 2022. https://www.sleepfoundation.org/how-sleep-works/why-do-we-need-sleep

9. Moore RY. Suprachiasmatic nucleus in sleep–wake regulation. Sleep Medicine. 2007;8:27-33.

10. Brzezinski A, Rai S, Purohit A, Pandi-Perumal SR. Melatonin, Clock Genes, and Mammalian Reproduction: What Is the Link? International Journal of Molecular Sciences. 2021;22(24):13240.

11. Wamsley EJ, Stickgold R. Dreaming and offline memory processing. Current Biology. 2010;20(23):R1010-R1013.

12. Walker M. Why Your Brain Needs to Dream. Greater Good. Published October 24, 2017.

13. Scarpelli S, Bartolacci C, D’Atri A, Gorgoni M, De Gennaro L, eds. The Functional Role of Dreaming in Emotional Processes. Frontiers in Psychology. Published March 15, 2019.

14. Zhang W. Freud’s Dream Interpretation: A Different Perspective Based on the Self-Organization Theory of Dreaming. Published August 23, 2018.