One of the most important discoveries is that in modern urban society, few people sleep the way most humans did for all of our evolution before the introduction of artificial lighting. For hundreds of thousands of years, humans thought that what the pushers of sleep meds promise — an uninterrupted night of seven or eight hours’ sleep — was an unnatural and undesirable thing.
Experiments by a team led by Dr Thomas Wehr at the National Institutes of Mental Health in Bethesda have supplied compelling evidence of how our technology has ripped us from our natural cycle. Deprived of artificial lighting for several weeks, the typical subject evolved the following pattern: lying awake in bed for an hour or two, then four hours sleep, then 2-3 hours of “non-anxious wakefulness” followed by a second sleep before waking for the day’s activities.
One of the most exciting findings in Wehr’s study involved the endocrinology of the night watch. The interval between first sleep and second sleep is characterized by elevated levels of prolactin, a pituitary hormone best-known for helping hens to brood contentedly above their eggs for long periods. Wehr concluded that the night watch can produce benign states of altered consciousness not unlike meditation.
Wehr and his team put their subjects on the Paleolithic plan, without alternatives to electrical light such as candles or fire or oil lamps. The Paleolithic two-sleeps cycle wasn’t only a stone age phenomenon; it was characteristic of how people spent their nights until gas lighting and then electricity became widespread.
A seventeenth century Scottish legal deposition describes a weaver as “haveing gotten his first sleip and awaiking furth thairof.” Sleep historian Roger Ekirch says that “until the modern era, up to an hour or more of quiet wakefulness midway through the night interrupted the rest of most Western Europeans” – and presumably most other people – so that “consolidated sleep, such as we today experience, is unnatural.”
This may help to explain the extent to which so many of us in our urbanized society are out of nature and out of touch with dreaming. “Segmented sleep” was the norm for our ancestors until quite recently, as it remains for some indigenous peoples today. Like Virgil and Nathaniel Hawthorne, the Tiv of central Nigeria speak of “first sleep” and “second sleep”. They wake at any time during the night and will talk to anyone in the hut who is also awake – often about their dreams.
Most interesting, the intermediate state the French called dorveille was widely regarded as an excellent time to birth new ideas. In 1769, the artful London tradesman Christopher Pinchbeck advertised a device called a “Nocturnal Remembrancer”, a parchment tablet inside a box with a slit to guide the writing hand in the dark to enable “philosophers, statesmen, poets, divines and every person of genius, business or reflection” to secure the “flights and thoughts which so frequently occur in the course of a meditating, wakeful night.”
It is possible that in our modern culture, through our suppression of ancient and natural circadian cycles, we have rendered ourselves (to quote Thomas Middleton) “disanulled of our first sleep, and cheated of our dreams and fantasies.”
While our modern sleep patterns may interfere with our awareness of night dreams and our ability to share them, new technologies for imaging brain activity tell us we are dreaming at night nonetheless — maybe dreaming all night long — and that some of the brain’s behaviors during sleep dreams are curiously similar to those associated with creative flow in other states of consciousness. The new science of dreaming suggests the following:
- Almost everyone dreams, every night — even someone who has suffered massive brain injury.
- Humans who conform to the modern sleep pattern average six dreams (or dream sequences) every night, whether or not they remember.
- While many researchers continue to associate dreaming with the rapid-eye movement (REM) state of sleep discovered in a Chicago laboratory in 1953, there is growing scientific evidence that dreaming — or at least some form of “mentation” — is going on all through the night.
- The behavior of the waking brain is quite similar to that of the dreaming brain during creative states, as when jazz performers enter a riff of improvisation.
- Dreaming plays a critical role in growing learning skills and consolidating memory. There is hard evidence, for example, that dreaming about newly learned material enhances subsequent recall of that material.
While brain science tells us important things about the quality of our reception, it no more tells us how our dreams are made than pulling apart a television monitor can show you how and where a movie produced and how it travels from a network to your screen. A true science of dreaming requires us to gather data outside the sleep labs, inside the dreamworld itself.
Adapted from The Secret History of Dreaming by Robert Moss. Published by New World Library.
Graphic: Salvador Dali “Sleep”