Embracing the darkness

What do we call the period between Halloween and Thanksgiving? I don’t know about you, but for me the shortening daylight hours signal the beginning of SAD season. Seasonal Affective Disorder. My symptoms are relatively mild, but they’re enough to make me really loathe this time of year.

However, a video linked to a friend’s blog got me rethinking my relationship with short days and long nights. Too much artificial light tells our mind and body it’s time to be awake.

A key factor in how human sleep is regulated is exposure to light or to darkness. Exposure to light stimulates a nerve pathway from the retina in the eye to an area in the brain called the hypothalamus. There, a special center called the suprachiasmatic nucleus (SCN) initiates signals to other parts of the brain that control hormones, body temperature and other functions that play a role in making us feel sleepy or wide awake… 

…Melatonin is a natural hormone made by your body’s pineal gland. This is a pea-sized gland located just above the middle of the brain. During the day the pineal is inactive. When the sun goes down and darkness occurs, the pineal is “turned on” by the SCN and begins to actively produce melatonin, which is released into the blood. Usually, this occurs around 9 pm. As a result, melatonin levels in the blood rise sharply and you begin to feel less alert. Sleep becomes more inviting. Melatonin levels in the blood stay elevated for about 12 hours – all through the night – before the light of a new day when they fall back to low daytime levels by about 9 am. Daytime levels of melatonin are barely detectable. 

Besides adjusting the timing of the clock, bright light has another effect. It directly inhibits the release of melatonin. That is why melatonin is sometimes called the “Dracula of hormones” – it only comes out in the dark. Even if the pineal gland is switched “on” by the clock, it will not produce melatonin unless the person is in a dimly lit environment. In addition to sunlight, artificial indoor lighting can be bright enough to prevent the release of melatonin.

Interfering with natural sleep patterns can negatively affect our mental and/or physical health. This is somewhat ironic, since the most popular treatment for SAD is exposure to artificial sunlight.

People who’ve spent their life in populated areas are often freaked out by the darkness when they first come to remote places—partly because it’s a new experience, partly because we tend to conflate darkness and danger. “Ack! There are things out there, and I can’t see them!” But then there’s their reaction to seeing so damn many stars. Live and in person. “Oh WOW!”

I’ve written before about people who are at a loss when restrictions prohibit campfires. What will they do in the evening if they can’t stare at the flames (and dodge smoke)? Stare at the sky instead, folks. Let your eyes adjust. Let your perceptions adjust. Observe the vastness of the universe. Feel your place in it.

So tonight I’m going to take my own advice. I’ll turn off the computer, go outside, and lie on my back until overcome by wonder and melatonin.