With the discovery of
electricity, industrial and technological development, control over energy,
food production, telecommunications, etc; and with social paradigms turning
towards “having” and “success”, international society has changed and developed
new habits and new tendencies towards work. Society is now continuous, first
24h per day, and then 7 days per week. Enjoyment changed and extended through
the night. In this setting, Sleep became and embarrassment for work,
productivity and economic interests.
Therefore, since last
century, people have been sleeping less and less, and this deficit extends to
all age categories.
Previously, no one
questioned how much a baby should sleep, now I am asked if 8 hours are enough?!
During my teenage years, we would have dinner early and TV broadcasts ended at
midnight with the national anthem, now dinner is had later and later, and TV
broadcasts never end. We would go out on a date with a “chaperon” and our
parent’s permission, and now sweethearts are together by starting at each other
through their cellphones. We would thank God for our “daily bread” and nothing
went to waste, nowadays there’s food in abundance inside shopping malls and
supermarkets.
We convinced ourselves
that we have no limits.
The number of poor is
increasing, and millions are beneath the poverty threshold; divorce and single
parent families increase; and so do Sleep related illnesses.
The warnings about the
risks of this behavior are many, but in global society they do not speak loud
enough, choked by the systematic challenges and incentives in the opposite
direction
However, the risks and
consequences are serious. In all ages and in all continents, not enough sleep
or too much sleep increases the risk of obesity, hypertension, type II
diabetes, accidents, cancer, depression, insomnia, and early death.
Superimposed on all these risks are those that affect the brain, reducing the
memory, learning, creativity, problem solving and affecting emotions and
emotional stability.
Why?
Because during sleep,
our brain, released from the focus given to the outside, shifts said focus
towards itself and towards our body; and both these dialogues are essential to
our health.
During Sleep, the millennia
old paradigm “a sound mind in a sound body” reaches its maximum intensity.
Our brain takes care
of itself, increasing the intensity of sleep in more stimulated areas while
awake (areas related to learning, for example), reconnecting important circuits
and bonding quick interconnections between zones that speak with one another,
disconnecting circuits in order to rest, deleting irrelevant information and strengthening
that which matters.
Since one does not
learn what one does not like, a sleeping brain stabilizes emotions; since to
learn one must experiment, our brain creates, through dreams, virtual realities
where, without risk, one can argue, run, fight, talk or cry; and since one must
innovate, dreams are about the impossible, without forgetting the root of that
which is real.
In teenagers and children,
loss of sleep increases distractibility and irritability, in opposition to
adequate sleep which consolidates memory.
On the other hand,
sleep deprivation affects memory of neutral and positive stimuli. This effect
leads to remembering negative stimuli, and enhances behavioral tendencies
towards impulsiveness to negative stimuli, and relating to a lesser degree of
expression towards emotional stimuli.
Sleep deprivation also
has behavioral consequences such as higher chance of trauma, unintentional accidents
in children, adolescents and adults.
The connection between
Sleep and Intellect has been indirectly appraised through connections between
Sleep Characteristics, having been found certain correlations between sleep
zones and IQ.
It is known that a
sleep episode following a learning period will enhance said learning. This is
said to be true for verbal tasks, motor tasks, special orientation tasks and
more specialized performances, such as playing music.
On the other hand, the
daytime apprenticeship of a motor task is related and linearly correlated with
the increase of Delta activity and Time Zones, in the following sleeping
period, in the contralateral motor region.
The effects of sleep
in memory consolidation have been described in early 19th and 20th
century, but there is presently a significant quotient of papers on the matter,
that restates the function and effect of sleep in memory consolidation,
procedure consolidation and also in declarative memory. On the other hand, not
only does sleep enhance but also protects declarative memory.
It is known since the
1960’s that declarative memory is affected by sleep or by sleep deprivation. A
36h sleep deprivation significantly diminishes the temporal sequence retention,
even if aided by heavy doses of caffeine, and also affects the correct
perception of said performance.
The idea that sleeps
enhances creativity is sprung by tales concerning several scientists and
artists who have disclosed having created their masterpieces right after waking
up, or after a dream or a hypnagogic stage.
A more detailed
disclosure is due to Kekulé, concerning a dream that leads him to the discovery
of the Benzene Ring. Others can be also mentioned: Singer’s discovery of the
sewing machine gearings, Dali’s paintings, Mr. Jeckyll’s Book by Stevenson,
Paul McCartney’s Imagine, Kurosawa’s “Dreams” film, amongst many others.
The effect of sleep is
not only to code and consolidate memories or learning, but rather to integrate
in into new associative schemes, that through generalization or integration,
could show new perspectives or directions, giving reason to the popular saying:
“Night brings good counsel”.
Several experiments
were conducted towards proving this integration capacity “again”, in adults as
well as in pre-lingual children.
Having been taken into
account, nocturnal sleep allows, for all age groups, the consolidation of
memories, and enhances concepts of information generalization, and the identification
of hidden solutions.
Knowledge concerning the
effects of sleep on emotions comes from the increase in irritability and bad
temper after a sleep deprivation night, characteristics that worsen if said
deprivation is repeated. Nonetheless, it is also known that acute deprivation
can also have an antidepressant effect, used years prior in the treatment of
serious depressions.
On the other hand, it
is known that both stress and positive or negative emotions happening during
the day both affect sleep.
An increase in
positive events contributes to a better subjective sleep, and a good night’s
sleep enhances the recognition of images with emotional components. Negative
events worsen sleep to many, good or bad, sleepers.
In this perspective,
sleep deprivation functions both as a time bomb for irritability outbreaks in
normal life and may explain depressive humor in many psychiatric disturbances.
At last, multiple
sleep related diseases, or medical diseases, both neurologic and psychiatric
that impact sleep in a primordial way, systematically affect memory, attention
and executive functions.
Thus, the habit of
sleeping less in intellectual workers significantly affects reasoning
capabilities (memory, learning, creativity), executive functions and emotional
abilities, which are essential to the execution of the intellectual tasks at
hand.
Therefore, if body and
brain are our tools, to put them in jeopardy equals killing “the hen with the
golden eggs” in every professional.
In conclusion: to
think right, it’s important to sleep right!
What about our body?
Risks to our body
related to sleep deprivation have already been said. Why?
During sleep periods, anabolic
hormones are systematically and regularly produced, meaning the growth hormone,
prolactin and testosterone, and catabolizing hormones are regulated,
particularly cortisol and the thyroidal hormone.
It all happens in a
way that you either grow or repair tissues in different organs while you sleep,
and reproductive functions are regulated. It all happens so that, in the
morning while waking up, cortisol is at an adequate level, in order for the day
to start well. But if you do not get enough sleep, anabolic hormones diminish
and catabolizing hormones increase, and health risks start to appear.
On the other hand,
sleep is essential in energy regulation and in homeostasis, for temperature
control, which goes down while we sleep, and for energy control through
nourishment, in a balance that diminishes our hunger or increases our hunger.
For all this, having not enough sleep leads to fatigue, and increases height
gain risk in all age groups.
Sleep as also a narrow
and complex relation with immunities, and not sleeping increases the chance for
infectious diseases and eventually auto-immune diseases.
While asleep, cell
division is controlled, therefore little sleep or out of hours or irregular
sleep increase the chance of cancer in both genders.
No limits - The
technological age’s grandest illusion.
Not sleeping is in
fact risking a roman aphorism: “A healthy mind in a healthy body”.
Professor Teresa Paiva
Lisbon, June 7th 2013