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The pineal gland is a miniscule gland located in the human brain which secretes melatonin in response to light. It is located at the top of the spinal cord where it ends inside the brain, just above the cerebellum. It is about the size of a grain of rice. A great deal of blood flows through it, similar to the kidneys, so that the different chemicals it puts out can circulate through the body.
This gland is also referred to as the "third eye." The name does not connote psychic abilities. Instead, certain similarities to the light-sensing retinas of the human eye have led evolutionary scientists to theorize that it evolved from the same organ. In some animals, there is even a small hole in the skull through which light can reach their equivalent of the gland. In human beings, receptors in the eyes lead directly to the gland.
The role of the pineal gland in the human body is still being explored. It is thought to send out varying levels of hormones in response to seasonal changes in light, and in some animals, it regulates the related breeding urges. In humans, tumors in the pineal gland can sometimes cause a too-early onset of puberty.
Primarily, the pineal gland secretes melatonin, without which a person cannot sleep. The 24-hour sleep-wake cycle in humans is regulated by the gland producing more melatonin in response to light. In nocturnal animals, the process is reversed so that they come awake in response to darkness. For this reason, melatonin supplements are prescribed for people who have severe insomnia and for those with jet lag.
It is thought that many other disorders may be related to the gland's melatonin production. Those with bipolar disorder, depression, or obesity have achieved some relief after being treated with melatonin, but results are so far inconclusive. Disruptions in melatonin production may even cause effects as diverse as headaches, cancer, and gallbladder stones.
The pineal gland has somewhat of a romantic history in medicine. Early doctors and anatomists dissected it, but were unable to discover its purpose. Its similarity to an eye was debated. The philosopher Descartes pointed out it had to be of importance because of its singularity. His reasoning was that in the symmetrical human brain, all parts are doubled, but the gland had no counterpart. Therefore, he theorized that it was the seat of all original thoughts in the human mind.
I wish it was that easy for me to get a good night's sleep. I have tried some melatonin supplements, but none of them seem to work for very long.
A few of them have worked for a couple weeks, and then after that they don't seem to have any effect.
I will have to check and see if the ones I was using were timed release or not. I will say, that some brands were better than others.
Sometimes I would feel really groggy the next day. It was nice to get some sleep, but I couldn't keep taking the supplement because I actually felt more tired through the day.
Has anybody else experienced this when taking melatonin supplements?
When I was younger, I would have never believed that I would have trouble sleeping. Now it seems like I rarely get a good night's sleep.
Even though I am exhausted, I can't seem to fall asleep. Other times I wake up several times during the night and can't get back to sleep.
A friend recommended that I try a melatonin supplement. The pineal gland must not secrete as much melatonin as we get older, because this seems to be a common problem for many people my age.
I have been thinking about trying an over the counter melatonin supplement. Has anyone been able to get a good nights sleep taking something like this?
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