It appears that our natural sleep
rhythm is to sleep shortly after dusk for approximately four hours and then be
awake for a couple of hours before once again sleeping if deemed necessary for
another four hours.
Perhaps we are meant to sleep
four hours in the evening and then perhaps sleep another four hours in the late
morning if necessary. What appears
natural is a four hour sleep cycle with a modest need for more that may or may
not be satisfied.
We have trained ourselves to use six
to eight hours instead without the middle break which appears ideal for
introspection and prayer or meditation.
All this is awkward to properly
plan or manage in terms of our commitments which appear to run from dawn to
late at night. However, this item makes
it quite clear that there are other sleeping arrangements that make possibly
better sense and may well suit the individual much better.
The myth of the eight-hour sleep
By Stephanie HegartyBBC World Service
22 February 2012 Last updated at 11:58 ET
We often worry about lying awake in the middle of the night - but it
could be good for you. A growing body of evidence from both science and history
suggests that the eight-hour sleep may be unnatural.
In the early 1990s, psychiatrist Thomas Wehr conducted an experiment in
which a group of people were plunged into darkness for 14 hours every day for a
month.
It took some time for their sleep to regulate but by the fourth week
the subjects had settled into a very distinct sleeping pattern. They slept
first for four hours, then woke for one or two hours before falling into a
second four-hour sleep.
Though sleep scientists were impressed by the study, among the general
public the idea that we must sleep for eight consecutive hours persists.
In 2001, historian Roger Ekirch of Virginia Tech published a seminal
paper, drawn from 16 years of research, revealing a wealth of historical
evidence that humans used to sleep in two distinct chunks.
His book At Day's Close: Night in Times Past, published four years
later, unearths more than 500 references to a segmented sleeping pattern - in
diaries, court records, medical books and literature, from Homer's Odyssey to
an anthropological account of modern tribes in Nigeria.
Much like the experience of Wehr's subjects, these references describe
a first sleep which began about two hours after dusk, followed by waking period
of one or two hours and then a second sleep.
"It's not just the number of references - it is the way they refer
to it, as if it was common knowledge," Ekirch says.
During this waking period people were quite active. They often got up,
went to the toilet or smoked tobacco and some even visited neighbours. Most
people stayed in bed, read, wrote and often prayed. Countless prayer manuals
from the late 15th Century offered special prayers for the hours in between
sleeps.
And these hours weren't entirely solitary - people often chatted to
bed-fellows or had sex.
A doctor's manual from 16th Century France even advised couples that
the best time to conceive was not at the end of a long day's labour but
"after the first sleep", when "they have more enjoyment"
and "do it better".
Ekirch found that references to the first and second sleep started to
disappear during the late 17th Century. This started among the urban upper
classes in northern Europe and over the course
of the next 200 years filtered down to the rest of Western society.
By the 1920s the idea of a first and second sleep had receded entirely
from our social consciousness.
When segmented sleep was the norm
·
"He knew this, even in the horror with which he started from his
first sleep, and threw up the window to dispel it by the presence of some
object, beyond the room, which had not been, as it were, the witness of his
dream." Charles Dickens, Barnaby Rudge (1840)
·
"Don Quixote followed nature, and being satisfied with his first
sleep, did not solicit more. As for Sancho, he never wanted a second, for the
first lasted him from night to morning." Miguel Cervantes, Don Quixote
(1615)
·
"And at the wakening of your first sleepe You shall have a hott
drinke made, And at the wakening of your next sleepe Your sorrowes will have a
slake." Early English ballad, Old Robin of Portingale
·
The Tiv tribe in Nigeria
Source: Roger
Ekirch
He attributes the initial shift to improvements in street lighting,
domestic lighting and a surge in coffee houses - which were sometimes open all
night. As the night became a place for legitimate activity and as that activity
increased, the length of time people could dedicate to rest dwindled.
In his new book, Evening's Empire, historian Craig Koslofsky puts
forward an account of how this happened.
"Associations with night before the 17th Century were not
good," he says. The night was a place populated by people of disrepute -
criminals, prostitutes and drunks.
"Even the wealthy, who could afford candlelight, had better things
to spend their money on. There was no prestige or social value associated with
staying up all night."
That changed in the wake of the Reformation and the
counter-Reformation. Protestants and Catholics became accustomed to holding
secret services at night, during periods of persecution. If earlier the night
had belonged to reprobates, now respectable people became accustomed to
exploiting the hours of darkness.
This trend migrated to the social sphere too, but only for those who
could afford to live by candlelight. With the advent of street lighting,
however, socialising at night began to filter down through the classes.
In 1667, Paris Lille in the
same year and Amsterdam
London didn't join their ranks until 1684 but by the end of the
century, more than 50 of Europe 's major towns
and cities were lit at night.
‘
Night became fashionable and spending hours lying in bed was considered
a waste of time.
"People were becoming increasingly time-conscious and sensitive to
efficiency, certainly before the 19th Century," says Roger Ekirch.
"But the industrial revolution intensified that attitude by leaps and
bounds."
Strong evidence of this shifting attitude is contained in a medical
journal from 1829 which urged parents to force their children out of a pattern
of first and second sleep.
"If no disease or accident there intervene, they will need no
further repose than that obtained in their first sleep, which custom will have
caused to terminate by itself just at the usual hour.
"And then, if they turn upon their ear to take a second nap, they
will be taught to look upon it as an intemperance not at all redounding to
their credit."
Today, most people seem to have adapted quite well to the eight-hour
sleep, but Ekirch believes many sleeping problems may have roots in the
human body's natural preference for segmented sleep as well as the ubiquity of
artificial light.
This could be the root of a condition called sleep maintenance
insomnia, where people wake during the night and have trouble getting back to
sleep, he suggests.
The condition first appears in literature at the end of the 19th
Century, at the same time as accounts of segmented sleep disappear.
"For most of evolution we slept a certain way," says sleep
psychologist Gregg Jacobs. "Waking up during the night is part of normal
human physiology."
The idea that we must sleep in a consolidated block could be damaging,
he says, if it makes people who wake up at night anxious, as this anxiety can
itself prohibit sleeps and is likely to seep into waking life too.
Stages of sleep
Every 60-100
minutes we go through a cycle of four stages of sleep
·
Stage 1 is a drowsy, relaxed state between being awake and sleeping -
breathing slows, muscles relax, heart rate drops
·
Stage 2 is slightly deeper sleep - you may feel awake and this means
that, on many nights, you may be asleep and not know it
·
Stage 3 and Stage 4, or Deep Sleep - it is very hard to wake up from
Deep Sleep because this is when there is the lowest amount of activity in your
body
·
After Deep Sleep, we go back to Stage 2 for a few minutes, and then
enter Dream Sleep - also called REM (rapid eye movement) sleep - which, as its
name suggests, is when you dream
In a full sleep
cycle, a person goes through all the stages of sleep from one to four, then
back down through stages three and two, before entering dream sleep
Source: Gregg
Jacobs
Russell Foster, a professor of circadian [body clock] neuroscience at Oxford
"Many people wake up at night and panic," he says. "I
tell them that what they are experiencing is a throwback to the bi-modal sleep
pattern."
But the majority of doctors still fail to acknowledge that a
consolidated eight-hour sleep may be unnatural.
"Over 30% of the medical problems that doctors are faced with stem
directly or indirectly from sleep. But sleep has been ignored in medical
training and there are very few centres where sleep is studied," he says.
Jacobs suggests that the waking period between sleeps, when people were
forced into periods of rest and relaxation, could have played an important part
in the human capacity to regulate stress naturally.
In many historic accounts, Ekirch found that people used the time to
meditate on their dreams.
"Today we spend less time doing those things," says Dr
Jacobs. "It's not a coincidence that, in modern life, the number of people
who report anxiety, stress, depression, alcoholism and drug abuse has gone
up."
So the next time you wake up in the middle of the night, think of your
pre-industrial ancestors and relax. Lying awake could be good for you.
Craig Koslofsky and Russell Foster appeared on The Forum from theBBC World Service. Listen to the
programme here.
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