The Pineal Gland, Melatonin & Sleep

The "Seat of the Soul," Our "Dreaming Neurotransmitter, Melatonin Synthesis, Relationship Between Cortisol & Melatonin, Brain Waves & Sleep Cycles

Courtney Snyder MD

Nov 04, 2024

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Sea otters sleep holding hands so they don’t lose each other.

There is so much to say about sleep. I’ll share what I find particularly interesting and important in this newsletter. I look forward to discussing tools for optimizing sleep in a future newsletter.

10 Thoughts on Sleep:

The Pineal Gland - is a small gland in the brain (between the back of our throat and the back of our head). It regulates our sleep-wake cycle - our "internal clock” or circadian rhythm. It also makes melatonin from serotonin (some of which is also made in the pineal gland). Light and dark in our environment trigger signals from the retina of our eyes to travel along a neuronal pathway to the pineal gland, letting it know how much melatonin it needs to make. Less is made when light hits our retina, which makes us feel awake. When it's dark, more is made, and we feel sleepy. You might even say the pineal gland synchs our rhythms to that of the earth.
Seat of the Soul - Since ancient times and across various cultures, the pineal gland has been considered sacred - the third “eye,” as if it sees or perceives beyond the physical realm. It has been considered the door to higher consciousness, mystical intuition, and insight. The French philosopher, scientist, and mathematician Rene Descartes claimed the pineal gland was the “seat of the soul.” Somewhat fitting with this idea of the pineal gland as a connection between our physical being and a universal energy or divine force is fascinating research suggesting that the pineal gland may function as a transducer of external electromagnetic fields (beyond light).
Flouride - The pineal gland is highly vascularized. There is evidence that fluoride accumulates in the pineal gland (on its own or through the assistance of calcium) and causes inhibition of melatonin synthesis. For example, a study looked at fluoride exposure in older adolescents and found that those with higher exposure had higher odds of sleep apnea and were more likely to have later bedtimes and wake times. A more recent study (May 2024) found a relationship between prenatal fluoride exposure and an increased risk of neurobehavioral problems among children living in an optimally fluoridated area in the US. Because of the research, a federal judge ruled that the current level of fluoride in water considered "optimal" by the Environmental Protection Agency is too high and that it "poses an unreasonable risk of reduced IQ in children."
Personal note - Aside from following the concerns about fluoride over the years, our dentist - Dr. John Kall, happened to be the Chairman of the Board of Directors at the International Academy of Oral Medicine & Toxicity (IAOMT), a group of professionals providing mercury & fluoride free biological dentistry & scientific resources for safety in healthcare. My daughter grew up in a house with fluoride-free toothpaste. We even filtered fluoride from the drinking water. Now an adult, she’s still not had a cavity; however, she also didn’t eat a lot of sugar.
Melatonin - also called our “dream neurotransmitter,” is pretty amazing. Aside from putting us to sleep and increasing our REM sleep (which I’ll get to), it also:
1. stops the excessive secretion of cortisol when we are stressed
2. improves our carbohydrate metabolism
3. improves our immune response
4. has antioxidant effects
5. promotes DNA repair
6. lowers triglycerides, inhibits hardening of the arteries, and decreases the progression of certain tumors
Creating Melatonin - involves four steps. L-tryptophan turns into 5-hydroxytryptophan, which turns into serotonin, which turns into n-acetylserotonin, which turns into melatonin. Each step requires an enzyme coded by a gene. To give you a sense of some factors impacting these genes and enzymes - one of the genes requires methylation. How optimally we methylate could impact this process. One of the enzymes needs B6 as a cofactor. If B6 is depleted (as we see in pyrrole disorder), melatonin production could be impaired. Many with pyrrole disorder are “night owls.” They don’t necessarily have problems falling asleep; they just don’t have the desire to go to sleep until later into the night. Also many have little or no dream recall, again likely because of a decrease in melatonin. Fortunately, we know how to optimize B6.
Cortisol - There is an inverse relationship between melatonin and cortisol. When stressed, cortisol levels go up (and melatonin levels go down) to prepare our body to fight or flee. You can see how adaptable this is. We don’t want to feel sleepy when our life depends on it. But often, our life doesn’t depend on it, and we can have problems sleeping when under stress. But again, we have a lot of ways to lower stress and lower cortisol so that we can increase melatonin and get restorative sleep.
Brain waves - are a measure of how active our brain is. The quality of these waves changes during our waking and sleeping states. If we pay attention, we can notice when our brain is in most of these states.
1. Beta Waves:
  1. Short/low amplitude fast waves (15-40 cycles/second)
  2. When our mind is highly engaged - thinking, mental and intellectual activity, and concentration.
  We also have gamma waves (35-100 cycles/second). Think amplified beta. They are also called “super-learning waves” and are involved in integrating thoughts, highly focused problem-solving, and learning.
2. Alpha Waves
  1. Non-arousal
  2. Slow higher waves (9-14 cycles/second)
  3. When we take a moment to reflect, meditate, or take a walk after being in beta
  When we are in alpha, to a degree, we are accessing more of the right brain, and in beta, we are accessing more of the left brain.
3. Theta Waves
  1. Daydreaming and when we are prone to a flow of ideas, free of guilt and censorship…..and also present during REM sleep when we are dreaming. Our mind is no longer focused on our external environment, body, or time and has shifted internally.
  2. Typically a very positive mental state
  3. Greater amplitude and slower frequency (5-8 cycles a second)
  4. When we take time off from a task and begin to daydream
    - Driving on a freeway (and unable to recall the last 5 miles)
    - In the shower while doing automatic tasks (mentally disengaged). This is often when those great ideas or solutions to problems show up
    - Running or doing other repetitive aerobic activities. I suspect Gandhi got into theta by spinning thread on a spinning wheel.
4. Delta Waves
  - Highest amplitude and slowest frequency (1.5-4 cycles per second) (Zero cycles per second would be brain-dead)
  - In deep, dreamless sleep, we are in the lowest frequency (2-3 cycles/second).
Falling Asleep & Waking Up - Falling asleep might look like reading for a few minutes (in low beta) and then turning off the lights and closing our eyes (from beta into alpha), then entering a daydream-like state (theta), and then falling asleep (delta). You can see why doing a highly intense mental activity right before bed could make getting to those slower waves more difficult. Conversely, when we wake (or are woken, for example, by an alarm), we may come out of delta (or even theta if we wake during REM sleep) and move through theta, alpha, and then beta. Our mind has returned to the external world.
REM (rapid eye movement) versus non-REM sleep
1. REM sleep (rapid eye movement behind closed eyelids)
  1. Induced by melatonin
  2. Theta waves while asleep
  3. The brain is more active - when vivid dreams occur
  4. Plays a role in memory consolidation, learning, creativity, connecting ideas, and mood regulation
  5. Increase blood flow and metabolism in certain brain regions
  6. Breathing is irregular
  7. Heart rate increased
  8. Muscles are completely relaxed and limp.
    While in medical school, I lived in an old apartment with a poorly sealed window, and I would have to clean mold off regularly. I would have sleep paralysis, meaning my mind would wake up while my body was still in REM. It’s a bit scary. Of course, I didn’t know about mold toxicity, nor can I now confirm that was the cause, but I suspect it was at play.
2. Non-REM sleep
  1. Blood flow and metabolism are reduced
  2. In delta brain waves
  3. Helps the body repair issues, builds bone and muscle, and strengthens our immune system
Sleep cycles - During our sleep, we are alternating between REM and non-REM sleep. This occurs in 90-110 minute cycles, though the first cycle may be shorter at 70 minutes. We typically have between four or five cycles each night. With each cycle, the amount of time we are in REM increases. About 25 percent of the night is spent in REM sleep. If we wake during REM sleep, we are more likely to remember our dreams.

I hope I’ve helped increase your respect for the pineal gland, melatonin, and our natural rhythms. I look forward to connecting some of these dots to sleep disorders, tools for improving sleep, and understanding dreams from neuroscientific, psychological, and spiritual perspectives.

Holistic Psychiatry

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