Time:
Biology and Technology
Nita Sturiale
INTRODUCTION
A history of time measurement is often a detailed chronology of the
evolution of instruments crafted to accurately tick away the passing
moments. Since the first sundial, science and technology has demanded
more precise time-keeping instruments and gotten them. To date, the
accuracy of the hydrogen maser clock is 1 second in 32 million years. In
this paper, I argue for the need to re-evaluate the relationship between
human beings and the consequences of this kind of technology. In order to
more accurately understand the nature of time measurement one must take
into account the complexities of human biology. In a relatively short
time, inventive minds have been able to create awesome and miraculous
machines yet our bodies have not evolved so quickly. It is necessary to
work towards and greater understanding and respect for our body's
dependence upon the cycles of nature.
This "biological time" is fundamental to who we are and what shape we
are able to take in a changing environment. The daily, or circadian,
rhythms that our internal clock tracks are perhaps more accurate than any
external clock that could be constructed. It tells us when to go to
sleep. The need for sleep is dangerously undervalued in our culture and
this is a serious flaw in our technological mindset. The engineers who
develop new technologies and the CEO's of large companies that drive
production schedules need to incorporate what is known about biological
time and the brain's need for sleep into their plans. Sleep is not only
pleasant but it is necessary for cognitive development and the safe
application of technologies that become more powerful every day.
The history of technological advances in the accuracy of time
measurement has been, in part, a story of getting people awake and to
work on time. Perhaps a shift in view is necessary that instead focuses
on the necessity for workers to get enough sleep at the right time.
In order to argue this view, this paper is organized into three main
sections. First, an overview of the Biology of Time. Within this section,
details are given on circadian rhythms, the resulting behavior of sleep
in human beings and the role of rhythm at the neuronal level in the
brain. In the section entitled, Technology, I present a brief history of
the misconceptions that have developed since the beginnings of the
Industrial Revolution concerning the relationship between technology and
human beings and the resulting affects of this misconception. In the
final section, Time to Change, hopeful applications of new findings are
described that incorporate new knowledge of our rhythmic needs.
BIOLOGY OF TIME
This section is sub-divided into four parts. First a brief description
of the biological mechanisms that time biological processes. Then a more
detailed description of circadian rhythms in humans. Sleep, the most
important result of biological timing, is then explained according to the
work of Allan Hobson. Finally, recent findings on the role of rhythm in
the brain on a neuronal level are outlined.
Biological Clocks
The science of biological time perhaps began with those first conscious
observers of nature that became healers, dependent upon a detailed
knowledge of the plant life they used. The elaborate natural histories
depicted in Meso-American, Egyptian and even Paleolithic art is evidence
for the keen observations necessary for these creations. One can assume
that these artists and students of the natural world noticed the rhythmic
patterns in nature. Early artworks suggest that these early observers
noticed the rhythmic patterns of the opening and closing of flowers,
reproductive cycles, the timely appearance of tidal life in addition to
solar, lunar and seasonal cycles1. Their lives were deeply dependent on
these patterns and knowing them well ensured survival. The lives of
human beings have always been driven by rhythmic cyclical activity on
many scales, internally and externally.
There is a wide range of biological rhythms from a fraction of a second
to many years2. Electrical (electroencephalogram) recordings of our
brains express 1/10 of a second oscillations. Our hearts beat about once
a second. We breath about every 6 seconds. Woman menstruate on a 28 day
monthly rhythm and humans still harbor vestigial yearly hibernation
cycles. Even our cognitive development may depend on rhythmic cycles of
brain activity3, 4. Many of these cycles are shared with other mammals
while others seem to connect us to shared evolutionary origins with many
other species.
The study of biological clocks, "chronobiology" has recently exploded
with new information that reveals the complexity of our internal timing
system. As the science has delved deeper into the mechanics of our daily
rhythms, it is now clear that the apparent rhythms of the total organism
is really a collection of "multiple oscillations, all running together
harmoniously in a perfectly tuned condition" 5. Traditionally it had
been thought that the suprachiasmatic nuclei (SCN), a tiny bundle of
nerve cells in the brain, was the place where the body's clock resides
and becomes synchronized with external stimuli. Now, it is known that
the SCN is only one component of a much more complex system of
intertwining rhythms. The pineal gland, which produces melatonin aiding
in the onset of sleep, and the retina, which is directly linked to the
SCN are now considered two other important components of biological
timing6. Also, the molecular basis of these clocks is being extensively
researched.
The regular periodic changes in behavior and physiology that any
organism undergoes is driven by a biological clock mechanism. This
mechanism will continue to run for a time even when the usual
environmental stimuli (sun and moon, celestial motion, magnetic
information) are artificially removed. Daily, monthly, and yearly
rhythms are controlled by this clock in different organisms.
Circadian Rhythms
In humans, many functions occur daily; sleep/wake cycle, body
temperature changes, oxygen consumption, adrenal and pineal gland
secretion, kidney excretion, blood count, cell division and cell death -
to name a few. These are the circadian rhythms. The term circadian was
introduced by Franz Halberg in 1959 and comes from the Latin circa =
about and dies = a day7. The period of circadian rhythms are about a
day. In humans, our circidian day is almost 25 hours.
Written evidence of early observation of circadian rhythms appears in
the 4th century BC. Alexander the Great's scribe, Androsthenes, described
how the leaves of the tamarind tree opened during the day and closed at
night8. It was assumed that this change occurred due to the plants
response to environmental cues: the rising and setting of the sun. This
view began to change due to observations by the astronomer, Jean Jacque
d'Ortous de Marian. In1729, he also noticed that the leaves of a
particular plant opened during the day and closed at night. He went a
step further and moved this plant to a constantly dark environment. He
observed that the plant's leaves still opened and closed according to the
same light/dark schedule. In his report, he also noted his observations
of the sleeping patterns of bedridden patients who were not aware of day
and night but still seemed to sleep according to a daily pattern. De
Marian invited others to continue this line of research but he himself
returned to astronomy.
The observation of circadian rhythms has progressed into a sophisticated
science since de Marian's work in the 18th century9. The flower clock
proposed by the taxonomist Carolus Linnaeus in 1751 further detailed the
daily rhythms of different species of plants. William Ogle observed the
daily and predictable fluctuations of human body temperature in 1866.
Curt Richter published a paper in 1922 that characterized the properties
of circadian clocks in mammals based on studies of rats. In 1929, the
time telling talents of bees was documented by Karl von Frisch and
Ingeborg Beling. In 1932, Erwin Bunning demonstrated that plants and
insects still behaved according to circadian rhythms even after they and
their parents were raised in constant conditions (continuous light or
dark). His work showed that there exists an internal clock mechanism
that is genetically inherited. In the 1950's, Gustav Kramer and Klaus
Hoffman demonstrated that starlings use the sun to navigate even though
the sun moves throughout the day. They supposed that in order to do this
the birds must have access to an accurate clock so that it can reorient
itself to compensate for the sun's movement. Also in the 1950's, Colin
Pittendrigh worked to convince biologists of the importance of circadian
rhythms in understanding all aspects of life.
Pacemakers and Entrainment
In order for this system to work there must be a free-running timing
mechanism, or pacemaker, as the primary oscillator that measures time in
the absence of external periodic cues. The pacemaker in mammals had been
placed in the hypothalamus primarily due to the work of Curt Richter. By
systematically lesioning, removing, and interfering with almost every
part of the brains of blinded rats he deduced that the only area that
affected the circadian rhythms of these rats was the hypothalamus. It
wasn't until the early 1970's that at least one pacemaker was found to be
more specifically in the suprachiasmatic nuclei (SCN)10.
In order to synchronize these free-running pacemakers to environmental
conditions a process of entrainment occurs. This is the daily resetting
of the body's clocks to environmental cues11. The most influential cue is
the daily return of sunlight into our eyes. Experiments have traced the
path of radioactive substances injected into the retina straight through
the SCN. In this way, it is thought that the environment provides at
least visual cues for the free-running timing mechanisms in the SCN so
that this continuous beating can be entrained to match the slightly
changing patterns of the environment.
It is still unknown how many pacemakers are in the brain. Studies of
tidal marine life have shown that in order for these animals to behave
according to predictions of the changeable nature of tidal ebb and flow
they need at least two pacemakers12. Fiddler crabs studied at the shores
of Cape Cod know exactly when to emerge between the high tides in order
to feed and mate. These intervals are roughly 12.4 hours and the crabs
are exactly on time no matter when the tides ebb. These studies shed
light on the human system. At least two different rhythmic functions can
become desynchronized in human isolation experiments; that of the
sleep/wake cycle and core body temperature13. Perhaps there are several
other pacemakers in the human body.
Molecular Basis
Several pacemakers would be possible at the molecular level. This has
recently been extensively researched. Edmunds14 writes about the
cellular and molecular basis of biological clocks and states that
ultradian (less than a day) rhythms control the division of eukaryotic
cells, the bioluminescence of the unicellular algae, Goyaulax , and the
production of carbon dioxide in Neurospora fungi. He suggests that
circadian rhythms may be the products of a coupling among many higher
frequency oscillators that occur at the molecular level15. Others have
since confirmed this view. It is now thought that many intermeshing
molecular cycles each entrained by different cues culminate to create an
accurate clock16. Additionally, isolated neurons from the SCN express
independent circadian rhythms17. It has even been claimed that the
genetic material DNA itself is a circadian clock18.
Jeffrey Hall and Micheal Rosbash have been researching the timing
mechanisms of the fruit fly, Drosophila. They have identified two
proteins, Period and Timeless, that seem to be the source of the beat in
these insects. This shows that biological timing is not necessarily
simply the product of a complex intercellular network but may reside at
the molecular level19. Their work is significant because it suggests
that biological clocks appeared early in evolution and this shared origin
further reveals the fundamental and inescapable connection the human
species shares with nature.
The interaction between these molecular timers and the environment is of
primary importance to this paper. Entrainment is a delicate process that
can be disrupted or manipulated to change the rhythms at an appropriate
time. The work of J. Woodland Hastings from Harvard University and
others have identified particular mammalian substances that when injected
into the unicellular marine algae, Gonyaulax, can shorten and accelerate
the circadian rhythms by as much as four hours. His research is concerned
with the molecular components that participate in and regulate the
biological clock and the mechanism of the cellular oscillator itself.
This algae expresses its circadian rhythms with bioluminescence that
involves a daily synthesis and destruction of two proteins involved in
the biochemical reaction. Currently, his lab is cloning and sequencing
the genes for such proteins and studying their regulation. This research
suggests that there are biochemical mechanisms that constitute biological
clocks and enable them to be periodically entrained to environmental
conditions20. This work should give insight into the molecular mechanisms
that drive the circadian clock.
Interval Timer
To complicate things even further, most recently another component has
been discovered that is involved in the entrainment process. While
circadian clocks are reset every day by sunlight, another clock the
interval timer , a stop-watch, gauges the passing of seconds and
minutes21. Research into this component gives insight into the brain's
mechanisms for doing the computations necessary to accurately measure
such small amounts of time. Randy Gallistal, a behavioral neuroscientist
from the University of California, says:
"what all this interval timing research shows is that animals are
storing the value of variables; that they know how long an interval has
lasted and they are writing that to memory, in much the same way that a
computer does"22.
Though these researchers have located where this interval timer resides
in the brain they have not yet found a chemical or molecular mechanism.
Sleep
The genetic, cellular and molecular mechanisms described above have all
conspired to make sure we get enough sleep. On an average we spend one
third of each earth rotation asleep. It is extremely difficult for
humans to stay awake longer than 2 or 3 days. Yet, our ability to be
entrained to environmental cues is also powerful. If we must, we can stay
awake and even experience periods of productivity on little sleep. But in
the end the loss causes us internal trouble and our biological clocks
struggle to get back on schedule23. The lack of sleep has dangerous
risks. In J. Allan Hobson's Sleep, a collection describing the current
state of sleep research and understanding, he suggests that sleep is the
bodies best defense against infection as well as its most productive
state of growth and development. Babies spend more time in an REM sleep
state than adults while their brains are growing most rapidly24. Almost
all human growth hormone is released from the pituitary gland during deep
non-REM sleep. In humans, sleep is the most significant result of
biological timing.
In Sleep, Hobson chronicles the science of sleep and explains how though
neglected in the past, it has gained considerable attention recently.
Because sleep doesn't look like much from the outside, it was thought
that sleep was merely an absence of wakefulness for the purposes of
resting. Previously, the limitations of science could only treat dreaming
from a psychological perspective without causal connections. Now armed
with new physical evidence, Hobson claims that sleep is only found in
animals with highly developed brains. Other animals rest at certain
rhythmic brain states but sleep is not simply rest. Recent research has
shown sleep to be far more complex.
Costs and Conditions
The costs of sleep are tremendous. Without the ability to react to
danger quickly a sleeping animal is vulnerable. Hobson stresses this
vulnerable state:
"By abandoning temperature control, we make ourselves vulnerable to
being frozen or cooked; by abandoning vigilance, we expose ourselves to
surprise attack; by abandoning controlled consciousness, we risk
committing errors of perception, logic, and judgment. These are the
dangers of entirely normal sleep" 25.
Evolution has selected to take this risk. Why? The recent growth of
brain science has enabled a deeper view into the processes of sleep and
it is now considered a dynamic and complex human behavior fundamental to
consciousness. Hobson believes that a scientific theory of consciousness
is now possible more than ever before due to an enriched view of sleep
and dreaming26.
Sleep behavior can be conditionally defined as a state in which there is
relative immobility, relaxed posture, and decreased sensitivity to
sensory stimulation from the outside world. It occurs for a finite amount
of time and is periodically recurrent due to the rhythms of a circadian
clock system. The sleep state itself is made up of ultradian (90 minute)
rhythmic periods that fluctuate between non-REM(rapid eye movement) and
REM sub-stages. REM sleep is marked by increased brain activation
(dreaming), muscle-tone suppression, and rapid eye movement27.
Sleep Rhythms
The circadian rhythms described above ensure that we sleep at the most
efficient time during any given 24 hour period. This rhythm anticipates
the environmental conditions of night and causes the core body
temperature to dip during this time. This elegence in design is described
by Hobson:
"Accordingly, sleep is strategically placed on the descending limb of the
body temperature curve while arousal occurs when things are looking up
from a thermal point of view" 28
Also, we are unable to search for food during this time and sense of
hunger is conveniently missing. This has the added benefit of taking the
animal out of the competition for food a good part of the day - less food
is needed enabling the animal to compete more successfully for limited
food supply. These brain clock mechanisms have evolved to balance the
needs of survival and energy conservation.
In humans, the process of entrainment is particularly important in view
of our lifestyle. Because our free running pacemakers mark an
approximately 25 hour day (other species have different pacemaker
periods) we constantly have to set our clocks to match environmental
conditions. In isolation experiments, subjects sleep/wake cycle
increases each day and eventually they "lose" days. Hobson remarks on
this mismatch:
"These results mean that humans have a natural tendency to sleep at a
frequency that is slightly different from what will in reality be most
adaptive" 29.
Circadian rhythms and the REM/dream cycle rhythms are interconnected in
many important ways. The amplitude of REM rhythms is maximized at the
low point of the circadian rhythm30 . This is very important to the
argument presented in this paper. Assuming that dreaming is fundamental
to cognitive development and health, then it is important that an
individual maximizes dream time. If dream time occurs best at a
particular time in the circadian schedule than we should sleep when our
biological rhythms tell us to. Evidence also shows that whether or not
the REM state occurs during midday naps also depends when in the
circadian day the nap occurs31. In other words catching up on rest does
not necessarily ensure catching up on the more complex results of REM
behavior.
Function of Sleep
The functions of sleep are only recently becoming more clear though it
is still predominately theoretical. Hobson explains that sleep serves at
least two general functions: homeostasis and heteroplasiticity.
Homeostasis creates the constancy needed by the body. This is maintained
during sleep by lowering the metabolic rate of the body. This conserves
energy and simultaneously reduces the risks of extreme temperature
changes that occur during the coldest part of the night.
Heteroplasticity is the brain's function of adapting to change by
changing itself. During sleep the brain's learning processes are
inactivated which provides a time for the brain to reorganize and more
efficiently store information already in the brain32. In this way, when
the body wakes it is prepared to take in new information and learn more.
According to Hobson, the REM state of sleep enables both energy and
information management by arresting the firing activity of a certain
group of neurons that participate directly in information acquisition.
Without these neurons memory is impossible. These same neurons
participate directly in temperature control. This feedback loop is
fundamental to our cognitive abilities and physical health. Without
sleep, the body usually loses the function of alertness, becomes prone to
disease and may suffer long term developmental risks.
Powerful evidence for the importance of sleep is demonstrated by an
experiment designed by Allan Rechtschaffen in 1983[33]. In his
experiment, two rats were contained in a cage divided in the middle with
a rat on either side. They were both allowed to eat and drink at will.
When the experimental rat fell asleep it triggered the platform of the
cage to rotate waking him up after only a short doze. The other rat could
sleep uninterrupted. After the first week(the limit of human sleep
deprivation experiments) no remarkable change was found. After two
weeks, the sleepless rat began to show marked changes. Its paws became
damaged and it began to eat more and lose weight. This weight loss was
due to a metabolic dyscontrol - more and more calories were needed to
maintain energy balance. After 4 weeks the rat died having lost the
ability to regulate body temperature and fight disease. One can assume
that prolonged interference with sleep in humans has at least similar
affects in body and mind.
Brain Rhythms and Cognition
Rhythm in the brain is the basis for consciousness. Not only do
circadian rhythms ensure that we sleep enough but rhythm may be the basis
of consciousness itself. One of the many mysteries in the study of the
brain and cognition is the question of 'binding'. There are many regular
rhythms in the different areas of the brain that become synchronized when
these areas respond to the same stimuli. It has been suggested that
these brain rhythms encode sensory information34. Cortical oscillations
have been extensively measured by EEG (electroencephalography) techniques
and patterns have been found that correlate with different brain states.
How are the workings of so many individual and distant neurons
coordinated into a single idea or perception in a given moment35?
Several new theories are attempting to answer this question.
The results of work done by Silva, et al (1991)36 suggests that networks
of intrinsically rhythmic neurons in a particular layer of the cerebral
cortex can initiate synchronized rhythms and project them onto neurons of
other layers. Some of these cortical oscillations have been known to be
driven by the thalamus, but new data reveals that some oscillations
emerge in the cortex itself independent of the thalamus.
In the outer layers of the brains cortex, there is a subpopulation of
excitatory pyramidal cells that are widely connected to other neurons
both near and far in the brain. These particular cells react to stimuli
with rhythmic bursts of firing at 30 to 60 times per second. With this
rhythmic bursting they propagate a rhythm to other neurons.
In addition to this mechanism, another system exists in which
interneurons (neurons that inhibit the firing of other neurons) respond
to stimuli by vibrating at 40 hertz - a rate determined by how long it
takes currents flowing between interneurons to decay. Other cells linked
to these interneurons respond by also oscillating at 40 hertz. According
to a computer model designed by Roger Traub37, when the patterns of
excitatory neurons and the interneurons are combined, the pyramidal
neurons will also fire at 40 hertz even when they are at great distances
from each other. This is due to the activity of the interneurons which
fire two rapid spikes to make up for the distance. The time between the
rapid spikes is the time it takes for a nerve impulse to travel form one
group of neurons to the next, which in turn keep the two groups in step.
The point here is to show that the rhythm in the brain that is deeply
fundamental to our very consciousness cannot be separated from the timing
of our circadian rhythms and our need for adequate sleep. It is suggested
that the maintenance and awareness of our circadian rhythms ensures the
synchronization of brain rhythms that are directly related to cognition.
To summarize, I have shown that the timing of biological clocks, the
onset of sleep behavior at the right time in the circadian day, and the
role of rhythm at the neuronal and molecular level are fundamentally
intertwined. The complex molecular basis for this timing suggests that
this system is not one that can be changed too easily. This interaction
is the very nature of consciousness. Assuming that the intent of
technology is towards human survival and cognitive evolution, its
designers and users must incorporate the knowledge of biology into their
work for successful and efficient product. In the following section, it
is suggested that this is not the current state of affairs.
TECHNOLOGY
In this section, misconceptions about the relationship between
technology and human beings are introduced followed by a description of
the dangerous results of these views.
Misconceptions
Our technological culture has developed without regard for what makes a
healthy, productive and reliable individual. Hobson accuses capitalist
society for not valuing sleep38. It is considered time away from
production. Yet, technology is only as powerful and beneficial to its
creators as the weakest link in the chain of production. Until reliable
artificial intelligent machines are developed, that weakest link is often
an exhausted individual who sits behind the controls at 3:00 am. We have
created technological advances that have replaced the need for human
workers in sensitive positions. Less humans are needed but this in turn
places a tremendous amount of power into the hands of a single individual
who sits at the controls39.
In his book, The Twenty-Four-Hour Society, Moore-Ede describes the
"design specs" of the human body and states that science and technology
have failed to work with these in mind. He suggests that new ways of
working and designing technologies must be put in place that include the
design specs of the human body as a major factor. He explains:
"At the heart of the problem is a fundamental conflict between the
demands of our man-made civilization and the very design of the human
brain and body. Fashioned over millions of years, we pride ourselves as
the pinnacle of biological evolution. But the elegant organization of
cells and chemistry, structure and systems, sinews and skeleton, that is
the human being, was molded in response to long-outdated design specs
that we seem to have forgotten. Our bodies were designed to hunt by day,
sleep at night, and never travel more than a few dozen miles from sunrise
to sunset. Now we work and play at all hours, whisk off by jet to the
far side of the globe, make life-or-death decisions, or place orders on
foreign stock exchanges in the wee hours of the morning." 40
A misconception about the human body entrenched itself into Western
culture with the Industrial Revolution: man is a machine. We use
mechanistic metaphors to describe ourselves41. When describing our
circadian rhythms, words like pacemaker, networks, oscillators, systems,
controllers are used. These metaphors are useful to a point, for there
are similarities between a body and a machine. Yet, this point has been
reached.
Before the Industrial Revolution, the farmers and craftsmen of cottage
industries were not slaves to time but worked according to their own
schedules and needs42. They were used to working at their own pace,
taking breaks as desired and picking up the pace when they felt it
necessary. As the evolution of industry progressed, pressure from
merchants, consumers, the development of road networks and eventually
railroads, demanded that these individual producers mold their schedules
to meet external time-tables.
This misconception has grown larger with time and we continue to force
the human body into system that strives to account for smaller and
smaller units of time. The increasing speed and production of technology
cannot be matched by the human body. J.B. Priestley observes:
"In the advanced science and technology of our own age, even a second can
be regarded as a great clumsy piece of time..." 43
In his writing, Priestly points out another illusion of increased
technology. It is thought that technology will magically provide us with
more time to expand and enrich our experience, yet it is actually taking
time away. The users of technology must organize themselves to better
manage time.
Dangerous Results
Advances in transportation and the creation of factories pushed the
biology of animals and humans to the limit. The rapid growth of industry
packed workers into cramped, dark, urban quarters where the sunsets and
seasons lost their importance. Ancient patterns of living were
destroyed44. The push for speed caused horses to die from exhaustion
until the railroad was in place45. When the railroad was in place,
fatalities occurred in the effort to build them faster and meet schedules
on time. The frequency of tardy factory workers meant employers had to
demand fines to force already underpaid workers to get to work on time46.
We have all experienced the consequences of pushing the limits of our
biology. I remember the trucker who drove through a neighbors house in
the early morning hours and the handful of times I've scared myself while
driving after a long day. The consequences have continued to grow in
magnitude since the beginning of the Industrial Revolution. No longer is
a single person's life at stake but many 100's as well as the vitality of
planet upon which we live. The stakes are higher. To name a few of the
many expensive and often fatal catastrophes of this push47: the shooting
down of a civilian Iranian airbus over the Persian Gulf in 1988 by a US
Navy Cruiser, the Challenger Space Shuttle accident of 1986, the 1989
Exxon Valdez oil spill, the Bhopal chemical accident in 1984, Chernobyl
in 1986, Three Mile Island of 1979. Many of these "accidents" occurred
in the wee hours of the morning because of exhausted workers unaware,
unreliable and in dire need of sleep.
Moore-Ede warns us never to go the hospital for emergency care at 4 am
in July, especially at a teaching hospital48. This is the time of year
when young, inexperienced medical students become interns and interns
become residents. Fatigue and incompetence are the over-riding factors
that permeate the emergency rooms. These residents, interns and nurses
are often working 12 to 36 hour shifts. They are working up to 130 hours
a week and making life or death decisions on hourly wages that are often
less than working at McDonalds.
The annual costs of fatigue are formidable. Major catastrophes (like
Chernobyl), airline crashes, industrial and trucking accidents, and auto
crashes with a tired night-shift worker at the wheel, have been estimated
to cost over 16 billion in the United States and over 80 billion in the
world49. The costs of lost productivity due to fatigue are even higher:
55 billion in the United States and 267 billion in the world50.
Moore-Ede has also indicated the physical and social costs of fatigue and
desynchronized biological time: chronic sleep disorder, gastrointestinal
disorder, cardiovascular disorder, mood disorder, chronic illness,
failure of parental attention, increased family stress51. There is also
growing evidence for longer term effects. Research has shown that men
who live in cities are losing their capacity to adjust their circadian
rhythms to the seasons. In other animals this would seriously affect
reproduction, but this connection has not yet been researched in humans.
Money, lives, mental health and perhaps even our fertility are the prices
paid for the increased mechanization of our lives.
To summarize, the use of technology has become a runaway train since the
beginning of the Industrial Revolution. Technology itself is not the
problem. Humans have developed it without attention to themselves, the
users of technology, and the stakes of this inattention are serious and
will continue to increase unless new information about biological timing
is put into practice.
Time to Change
With the recent discoveries in cognitive neuroscience, circadian rhythm
research and sleep studies it is now possible to make changes in the way
technology is designed towards a more appropriate and efficient
relationship with human beings. I am not suggesting that humanity return
to a hunting and gathering lifestyle. It is much more exciting and
interesting to use this new information to create new solutions to these
new problems. The inventive nature of the human mind provide an
opportunity to learn and adapt our behavior. Knowing the circadian
rhythmic needs that influence the efficiency of our mind and body, we can
design and evolve new ways of working that take into account our physical
limitations. Some are already paying attention to the recent science of
biological timing and sleep studies and are developing systems of
organizing human activity that work. Shift work has been redesigned in
industry. Travelers can arm themselves against Jetlag. Educational
systems and the medical industry have already begun to benefit from this
new era of knowledge.
Industry
The National Science Foundation's Center for Biological Timing has made
a great deal of headway in its study of shift-work, which affects 20
percent of the workforce in the United States. This center was recently
approached by a major American steel manufacturer with the opportunity to
analyze an existing database containing the records of 6,000 workers for
the last five years, The center is currently quantifying the raw data and
has devised a system to account for variables such as job danger and
performance pressures. In addition, the center has devised a system for
classifying jobs so that more comparisons can be made across disciplines.
Once the analysis is complete, the center hopes to develop and test a
number of interventions to see if they improve the health and safety of
shift workers at the steel company52 .
Jetlag
Fortunately for frequent travelers there is now enough known about
circadian rhythms to avoid the results of jetlag53. The insomnia,
fatigue, lack of awareness, and indigestion that accompanies travel can
be avoided simply by paying attention to the biological rhythms of the
traveler. The adjustment of these rhythms going eastbound is more
difficult than westbound travel. When flying east one is essentially
moving into the sun and losing the number of hours depending on the
number of time zones you fly over. The travel is taking away the time you
need to sleep. When flying west one is running with the sun and gaining
time. One way to reduce jet-lag is to systematically wake up earlier and
earlier in the mornings before east-bound travel. By the time you arrive
to your new destination it will be easier to adjust to the new location's
schedule.
Education
Some school systems in the US have decided to let high school students
get an extra hour of sleep in the morning54. In Edina, Minn., school
starts at 8:30 am instead of 7:15 am like most other schools in the
country. I remember my own painful high school experience - getting up
at 6:45, after several alarms and cold water fights with my father, and
staggering out into the cold darkness still half asleep, unable to see,
never mind solve math problems. These early morning hours mean
adolescents aren't getting enough sleep and their academic performance
suffers.
The medical community of Minn. pushed for this time change because they
are convinced that the poor grades and the number of teen-age car crashes
are directly linked to inadequate sleep. The biological clock is reset
during puberty and students stay up later and need to sleep later.
Eventually they learn how to train themselves to get to bed earlier or
they develop to need less sleep. However, during the high school years
an adolescence is going through dramatic changes that the school schedule
antagonizes unnecessarily. Studies have shown that an average adolescent
needs 9.2 hours of sleep to maintain optimal alertness. In a survey of
3120 students, the average amount of time spent actually sleeping was
only 7.3 hours. 26% of the students surveyed only slept 6.5 hours or
less. The hours of sleep correlated with academic achievement. Those who
slept more got better grades.
Medicine
Efforts have been made to control the overworked conditions for interns
and residents in hospitals. In the mid 1980's, Sidney Zion, the angry
father of Libby Zion, an 18 year old who died unnecessarily at the hands
of overworked residents in a NY teaching hospital, campaigned for change.
He convinced Dr. David Axelrod, New York State's health commissioner at
the time, to work towards changing the New York regulations of working
hours allowed by interns and residents. Axelrod designed new regulations
that were met with strong disapproval by hospitals, senior physicians and
insurance companies. Yet, these efforts have placed the issue into
center-stage and change is happening. Massachusetts teaching hospitals
have since put similar regulations into place without legislation. New
Zealand has developed a model system that limits a doctor's work week to
72 hours. The results have been clear. Doctors are more alert and
enthusiastic. Patient care and medical education have also improved55.
To summarize, there is hope for change. There are now many efforts
devoted to the study of biological time and sleep behavior. A quick
search on the Internet reveals many sites devoted to biological timing
research projects all over the world. Making changes in the way
individuals, CEOs, and policy makers view the biological basis for the
relationship between human being and technology demands an integrative
approach between disciplines. Different disciplines must come together
to compare patterns and look for correlation's in their data. The
National Science Foundation's Center for Biological Timing is working to
"increase public awareness of the importance of circadian rhythms to the
well-being of society"56 . This research center is one example of the
most recent efforts toward collaborative research. The Center for
Biological Timing was established by the National Science Foundation in
1991. It combines investigative efforts from the University of Virginia,
Northwestern University, Rockefeller University and Brandeis University.
Center investigators study aspects of biological rhythms through research
programs that cross traditional disciplinary boundaries. Neuroscience,
psychology, biology, physics, and mathematics all have something to say
to each other. An interdisciplinary approach to making scientific
discovery and appropriate application decisions of the technology that
arises out of this science will have exciting ramifications for the
future.
CONCLUSION
Everything from the depression due to Seasonal Affective Disorder (SAD)
to the scheduling of cell death is determined by biological timing
mechanisms. Brain and behavior development is now being attributed to a
rhythmic cycling of brain activity over time57. Most significantly, it
is clear that the form and quality of sleep vary significantly depending
on when in the circadian cycle sleep occurs. It is also clear that sleep
is fundamental to human cognition, development, and performance. The
application of this knowledge is necessary if we are to adapt and solve
some of the challenges that are now confronting society. Exploring the
wonderful complexity of biological time and cognition has the potential
to create safer and more adaptive technologies. There needs to be an
opportunity for human beings to catch up to their inventions.
In addition to these reasons, this study also reveals the deep
connections we share with the rest of nature. Aveni poetically describes
this deep connection:
"We feel time not only as an endless flow of metronomic beats but also as
a kind of rhythmic surge, a recurring pattern we can trace to our very
roots, to an age before we could call ourselves human beings- when we
came out of the sea." 58
At the edge of the sea, marine life is driven by tidal motion. These
animals know when to react to the tidal changes without environmental
cues. These tidal organisms provide hints toward and understanding of
our own biological timing. Exploring biological time is not only
technologically practical but it is also psychologically meaningful. It
reveals and reconnects us to the evolutionary origins we share with the
natural world around us. Rather than maintaining a lop-sided emphasis on
the creation of more accurate and higher frequency time measuring
instruments, perhaps what is needed is to pause and shift the focus onto
the time that nature tracks. An explanation to the nature of time has
been within us, at the molecular level, all along.
ENDNOTES
1 Priestley, J.B. Man And Time. London, Aldus Books Limited, 1964, pg.
138.
2 Aveni, Anthony. Empires of Time. New York, Basic Books, 1989, pg. 29
3 Silva, L.R, Amitai, Y. & Connors, B.W. "Intrinsic oscillations of
neocortex generated by layer 5 pyramidal neurons." Science, v251 (1991),
p432.
4 Thatcher, R.W. "Cyclic cortical reorganization: origins of human
cognitive development". In Fischer, K. & Dawson, G. (Eds.) Human Behavior
and the Developing Brain, New York, Guilford Press, 1994. p232 - 267.
5 Aveni, pg. 30.
6 Morell, Virginia. "Setting a biological stopwatch." Science, v271
(1996), p905.
7 Moore-Ede, Martin. The Clocks That Time Us. Cambridge, MA, Harvard
University Press, 1982, pg. 3.
8 Moore-Ede, Martin. The Clocks That Time Us. pg. 5.
9 Moore-Ede, Martin. The Clocks That Time Us. pg 5-16.
10 Moore-Ede, Martin. The Clocks That Time Us. pg. 157.
11 Moore-Ede, Martin. The Clocks That Time Us. pg. 22.
12 Palmer, John D. "Time, tide and the living clocks of marine
organisms." American Scientist, v84, n6 (1996), p570.
13 Moore-Ede, Martin. The Clocks That Time Us. pg. 157.
14 Edmunds, Jr. L.N. Cellular and Molecular Bases of Biological Clocks.
Springer-Verlag, New York, 1988.
15 Edmunds, Jr. L.N. Cellular and Molecular Bases of Biological Clocks.
pg. 72.
16 Welsh, D.K. Neuron, v14 (1995) p697-706.
17 Welsh, D.K. Neuron, v14 (1995) p697-706.
18 Hobson, J. Allan. Sleep. New York, NY, Scientific American Library,
1989, pg. 32.
19 Hall, Jeffrey & Rosbash, Michael. "Oscillating molecules and how they
move circadian clocks across evolutionary boundaries." Proceedings of the
National Academy of Science, v90 (1993), p5382.
20 Lee, D.-H., M. Mittag, S. Sczekan, D. Morse and J.W. Hastings.
"Molecular cloning and genomic organization of a gene for
luciferin-binding protein from the dinoflagellate Gonyaulax polyedr",
Journal of BioChemistry, v 268 (1993) , p8842-8850.
21 Morell, Virginia. "Setting a biological stopwatch." Science, v271
(1996), p905.
22 Morell, Virginia. "Setting a biological stopwatch." Science, v271
(1996), p905.
23 Aveni, pg. 30.
24 Hobson, pg. 71.
25 Hobson, pg. 189.
26 Hobson, pg. xiv.
27 Hobson, pg. 31.
28 Hobson, pg. 28.
29 Hobson, pg. 33.
30 Hobson, pg. 45.
31 Hobson, pg. 45.
32 Hobson, pg. 189.
33 Hobson, pg. 114.
34 Silva, L.R, Amitai, Y. & Connors, B.W. "Intrinsic oscillations of
neocortex generated by layer 5 pyramidal neurons." Science, v251 (1991),
p432.
35 Schechter, B. "How the brain gets rhythm." Science News, v274, n5286
(1996), pg. 339.
36 Silva, L.R, Amitai, Y. & Connors, B.W. "Intrinsic oscillations of
neocortex generated by layer 5 pyramidal neurons." Science, v251 (1991),
p432.
38 Hobson, pg. 115.
39 Moore-Ede, The Twenty-Four-Hour Society.
40 Moore-Ede, The Twenty-Four-Hour Society. pg. 6.
41 Aveni, pg.36.
42 Landes, David S. Revolution In Time. Cambridge, MA, Harvard University
Press, 1983, pg. 227.
43 Priestley, J.B. Man And Time. London, Aldus Books Limited, 1964. pg.
168.
44 Priestly, pg. 168.
45 Landes, pg. 229.
46 Landes, pg. 229
47 Moore-Ede, The Twenty-Four-Hour Society. pg. 3.
48 Moore-Ede, The Twenty-Four-Hour Society. pg. 94.
49 Moore-Ede, The Twenty-Four-Hour Society. pg. 68.
50 Moore-Ede, The Twenty-Four-Hour Society. pg. 70.
51 Moore-Ede, The Twenty-Four-Hour Society. pg. 71.
52 see The Center for Biological Timing Website .
53 Hobson, pg. 34.
54 Lamberg, Lynne. "Some schools agree to let sleeping teens lie." The
Journal of the American Medical Association, v276, n11 (1996), p859.
55 Moore-Ede, pg. 105.
56 Promotional website quote.
57 Thatcher, R.W. "Cyclic cortical reorganization: origins of human
cognitive development". In Fischer, K. & Dawson, G. (Eds.) Human Behavior
and the Developing Brain, New York, Guilford Press, 1994.p232 - 267.
58 Aveni, pg. 18.
REFERENCES
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Lee, D.-H., M. Mittag, S. Sczekan, D. Morse and J.W. Hastings. "Molecular
cloning and genomic organization of a gene for luciferin-binding protein
from the dinoflagellate Gonyaulax", Journal of BioChemistry, v 268
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Thatcher, R.W. "Cyclic cortical reorganization: origins of human
cognitive development". In Fischer, K. & Dawson, G. (Eds.) Human
Behavior and the Developing Brain, New York, Guilford Press, 1994. p232 -
267.
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