Melatonin

Before going deeper into how the different sleep disorders can affect the brain, I would like to touch upon a couple things that play a role in causing problems with sleep.

Anxiety, stress, and emotional problems all contribute to sleep disorders.  Additionally, according to research, many sleep disorders are caused by chemical imbalances in the brain and body. One of the hormones that appears to influence circadian rhythms is melatonin.

Melatonin enhances people’s ability to fall asleep. Its secretion is regulated by the pineal gland. The pineal gland is pea-sized pineal gland located in the center of the brain (pictured below).

The production of melatonin is controlled by the amount of light information relayed to the pineal gland from the suprachiasmatic nucleus (SCN). Secretion can be blocked by exposure to bright light at normally dark times (this is why they say that using our phones at night is eating away our sleep).

This is the reason night shift workers suffer from circadian rhythm disorders.  They sleep during the day when the sun is rising and their eyes are absorbing light when they are trying to sleep.

The cycle of regular melatonin release throughout the night is shown below. In most people, the pineal gland starts release melatonin a few hours before bedtime. It continues releasing it throughout the night. Production slows as we wake up and absorb the new day’s light.

It is also interesting to note that as we age, the amount of melatonin produced by our pineal glands decreases. This may be why many older adults have a more difficult time falling asleep.

Until next time!