Circadian rhythms & then some

Man's a diurnal creature, a being who, way back when, worked by day and slept by night, something not being done now as we move further into the age of never ending light, where the notion of adhering to circadian rhythms has gone the way of the dodo with potentially catastrophic results if the findings of one researcher proves to be true.

FOR MORE THAN 3 billion years, life on Earth was governed by the cyclical light of sun, moon and stars. Then along came electric light, turning night into day at the flick of a switch. Our bodies and brains may not have been ready.

A fast-growing body of research has linked artificial light exposure to disruptions in circadian rhythms, the light-triggered releases of hormones that regulate bodily function. Circadian disruption has in turn been linked to a host of health problems, from cancer to diabetes, obesity and depression. “Everything changed with electricity. Now we can have bright light in the middle of night. And that changes our circadian physiology almost immediately,” says Richard Stevens, a cancer epidemiologist at the University of Connecticut. “What we don’t know, and what so many people are interested in, are the effects of having that light chronically.”

Where it gets interesting

Yet biology at least supports some of the correlations. The circadian system synchronizes physiological function—from digestion to body temperature, cell repair and immune system activity—with a 24-hour cycle of light and dark. Even photosynthetic bacteria thought to resemble Earth’s earliest life forms have circadian rhythms. Despite its ubiquity, though, scientists discovered only in the last decade what triggers circadian activity in mammals: specialized cells in the retina, the light-sensing part of the eye, rather than conveying visual detail from eye to brain, simply signal the presence or absence of light. Activity in these cells sets off a reaction that calibrates clocks in every cell and tissue in a body. Now, these cells are especially sensitive to blue wavelengths—like those in a daytime sky.

But artificial lights, particularly LCDs, some LEDs, and fluorescent bulbs, also favor the blue side of the spectrum. So even a brief exposure to dim artificial light can trick a night-subdued circadian system into behaving as though day has arrived. Circadian disruption in turn produces a wealth of downstream effects, including dysregulation of key hormones. “Circadian rhythm is being tied to so many important functions,” says Joseph Takahashi, a neurobiologist at the University of Texas Southwestern. “We’re just beginning to discover all the molecular pathways that this gene network regulates. It’s not just the sleep-wake cycle. There are system-wide, drastic changes.” 

Maybe this is why the world seems to be so chaotic, so crazed, so over stressed and so amped. Makes sense to me as yours truly now goes to bed earlier, with no light, no sound, just darkness, similar to how man did it back in the day.

Darkness, Darkness

Be my pillow

Take my hand

And let me sleep

In the coolness of your shadow

In the silence of your deep

Darkness, Darkness

Hide my yearning

For the things I cannot be

Keep my mind from constant turning

Toward the things I cannot see now

Things I cannot see now

Things I cannot see

Darkness, darkness,

Long and lonesome,

Ease the day that brings me pain.

I have felt the edge of sadness,

I have known the depth of fear.

Darkness, darkness, be my blanket,

Cover me with the endless night,

Take away, take away the pain of knowing,

Fill the emptiness of right now,

Emptiness of right now, now, now

Emptiness of ri-ight now.

Darkness, darkness, be my pillow,

Take my hand, and let me sleep.

In the coolness of your shadow,

In the silence, the silence of your deep.

Darkness, darkness, be my blanket,

Cover me with the endless night,

Take away, take away the pain of knowing

Fill the emptiness of right now,

Emptiness of right now now now

Emptiness of right....

Oh yeah Oh yeah

Emptiness, emptiness

Oh yeah  - Jesse Colin Young, The Youngbloods