Role of Conscious and
Biorhythms in Organism’s Activity
Consciousness and its
• Consciousness is special form of perceiving
surroundings and goal-orientated activity of person with
interrelation to surroundings. Only social life forms
consciousness. It involves life experience of entire
• This ability of prefrontal areas to keep track of many
bits of information could well explain abilities to
prognosticate, do plan for the future, delay action in
response to incoming sensory signals, consider the
consequences of motor actions even before they are
performed, solve complicated mathematical, legal, or
philosophical problems, correlate all avenues of
information in diagnosing rare diseases and control our
activities in accord with moral laws.
The process of sensation and
• The process of sensation results in the transmission of
neural messages to the brain, where the psychological
process of perception occurs.We actively construct
perceptual conclusions about this sensory information.
• In arriving at those perceptual conclusions, we are
guided by well-established perceptual principles, such as
the cues that typically indicate distance, movement,
form, and so forth.
• But our perceptual conclusions can also be influenced by
a variety of psychological factors, including our
expectations, learning experiences, and experiences that
are unique to our culture.
The nativist position and empiricist
• The Gestalt psychologists believed that
perceptual processes are inborn, a viewpoint
called the nativist position. According to this
position, people everywhere, whatever their
background, see the world in the same way
because they share the same perceptual rules.
• Other psychologists have advocated the
empiricist position, believing that people actively
construct their perceptions by drawing on their
prior learning experiences, including cultural
• The Gestalt principles of
contribute to the illusion of
Visual illusions triangular contours of this
image. In organizing these
visual fragments, which are
lined up very precisely, the
Gestalt principles of closure
and good continuation
contribute to the perceptual
construction of a solid white
triangle covering three black
disks and an inverted
triangle. An intriguing
second illusion is also
occurring: The pure white
illusory triangle seems
brighter than the
surrounding white paper.
• Wilhelm Wundt’s investigations of consciousness, begun in
1879, were central to the development of psychology as a
field of study. Wundt’s approach, called structuralism, sought
to determine the structure of consciousness by recording the
verbal descriptions provided by laboratory subjects to various
stimuli, a method that became known as introspection.
• The next major approach to the study of consciousness was
the functionalism of William James, who focused on how
consciousness helps people adapt to their environment.
Behaviorism, pioneered by John B. Watson in the early
1900s, shifted interest from conscious processes to
observable behaviors, and the study of consciousness faded
into the background for almost half a century, especially in the
United States, until it was revived by the “cognitive revolution”
that began in the 1950s and 1960s.
Sigmund Freud’s model
• The existence of different levels of consciousness was at the heart
of Sigmund Freud’s model of human mental functioning.
• In addition to the conscious level, consisting of thoughts and feelings
of which one is aware, Freud proposed the existence of the
unconscious, a repository for thoughts and feelings that are
repressed because they are painful or unacceptable to the
conscious mind for some other reason.
• He also formulated the concept of the preconscious, which
functions as an intermediate or transitional level of mind between
the unconscious and the conscious.
• A preconscious thought can quickly become conscious by receiving
attention, and a conscious thought can slip into the
preconsciouswhen attention is withdrawn from it. In contrast, the
repressed material contained in the unconscious can only be
retrieved through some special technique, such as hypnosis or
dream interpretation. (What Freud called the unconscious is today
referred to by many psychologists as the subconscious.)
Consciousness: Carl Jung’s model
• Freud’s contemporary, Carl Jung, posited the
existence of a collective unconscious shared by
all people which gathers together the
experiences of previous generations.
• The collective unconscious contains images and
symbols, called archetypes, that Jung found are
shared by people of diverse cultures and tend to
emerge in dreams, myths, and other forms.
• In Jung’s view, a thorough analysis of both the
personal and collective unconscious was
necessary to fully understand the individual
• In response to morning light, signals from
photoreceptors in the eye are relayed via the
optic nerve to the suprachiasmatic nucleus. In
turn, the suprachiasmatic nucleus causes the
pineal gland to reduce the production of
melatonin, a hormone that causes sleepiness.
• As blood levels of melatonin decrease, mental
alertness increases. Daily exposure to bright
light, especially sunlight, helps keep the body’s
circadian rhythms synchronized and operating
on a 24-hour schedule.
Circadian Temperature Rhythm
The Biological Clock
• A tiny sliver of brain tissue, less than the size of a
pinhead, regulates the timing of our bodies. Within this
sliver lies a biological clock that keeps track of the time
of day, and seasons of the year, and marches our bodies
and brains in step.
• The small cluster of nerve cells that forms the biological
clock is called the suprachiasmatic nucleus (SCN). Its
name derives from the location of the SCN, just above
where the broad optic nerve trunks cross over each
other (a site known as the "optic chiasm") on their way
back from the eyes to the visual center of the brain.
• The SCN also receives information about light and dark
from the eyes, but it has its own dedicated pathway of
nerves, the retino-hypothalamic tract (RHT), which is
separate from the main nerve bundles carrying visual
information to the brain.
The Biological Clock
• We know that the SCN is a biological clock because
when it is destroyed in an experimental animal by
surgical pinpoint lesions of the brain, rhythms in sleep
and wake, and many other rhythms, fade away.
Interestingly, the animal, minus its SCN, runs, eats and
drinks the same total amount each 24 hours, but these
activities are now randomly distributed throughout the
day and night.
• One final fact about human biological clocks -- they
actually follow a pattern of about 25 hours. Hence, if
someone lives in a cave or an apartment without
windows (as people have done), their circadian patterns
of sleep and wakefulness shift "westward" by about one
hour a day. However, in the regular world, sunlight and
darkness serve to "reset" the biological clock every day
and keep us on a 24-hour cycle.
• Circadian rhythms are controlled by a master biological
clock-a tiny cluster of neurons in the hypothalamus in the
brain. This cluster of neurons is called the
• The SCN is the internal pacemaker that governs the
timing of circadian rhythms, including the sleep-wake
cycle and the mental alertness cycle.
• Keeping the circadian rhythms synchronized with one
another and on a 24-hour schedule also involves
environmental time cues. The most important of these
cues is bright light, especially sunlight.
• Normally the sleep-wake cycle, body temperature, and
the melatonin cycle are closely coordinated.
Suprachiasmatic Nucleus (SCN)
Role of melatonin
• The decrease in available light is detected by the SCN through
its connections with the visual system. In turn, the SCN
triggers an increase in the production of a hormone called
• Melatonin is manufactured by the pineal gland, an endocrine
gland located in the brain. Increased blood levels of melatonin
make a person sleepy and reduce activity levels.
• At night, blood levels of melatonin rise, peaking between 1:00
and 3:00 A.M. Shortly before sunrise, the pineal gland all but
stops producing melatonin, and a person soon wakes up.
• As the sun rises, exposure to sunlight and other bright light
suppresses melatonin levels, and they remain very low
throughout the day. In this way, sunlight entrains, or sets, the
SCN so that it keeps circadian cycles synchronized and
operating on a 24-hour schedule.
• People experience not only different levels, but
also different states of consciousness, ranging
from wakefulness (which may be either active or
passive) to deep sleep. Although sleep
suspends the voluntary exercise of both bodily
functions and consciousness, it is a much more
active state than was once thought.
• Tracking brain waves with the aid of
lectroencephalograms (EEGs), researchers
have identified six stages of sleep (including a
pre-sleep stage), each characterized by
distinctive brainwave frequencies.
Theories of sleep
• Two theories of sleep, the repair and the adaptive theories,
attempt to explain why sleep occurs.
• In the repair theory, sleep serves a biological need, replenishing
key areas of the brain or body which are depleted during the
• The adaptive theory suggests that sleep as a function evolved
over time because it prevented early humans from wasting
energy and exposing themselves to nocturnal predators, thus
aiding in survival.
• REM sleep in particular has been thought to serve special
functions. Research subjects whose REM sleep was interrupted
made up for the loss by spending extra time in the REM stage
on successive nights. It has also been suggested that REM
sleep aids the activity of neurons that use the neurotransmitter
norepinephrine, thus maintaining waking alertness. Persons
deprived of REM sleep have shown poorer retention of skills
learned during the day, leading to the hypothesis that REM
sleep helps in assimilating daytime learning experiences.
Stage 1 NREM
• As the alpha brain waves of drowsiness are replaced by
even slower theta brain waves, you enter the first stage
of sleep. Lasting only a few minutes, stage 1 is a
transitional stage during which you gradually disengage
from the sensations of the surrounding world.
• Familiar sounds, such as the hum of the refrigerator or
the sound of traffic, gradually fade from conscious
awareness. During stage 1 NREM, you can quickly
regain conscious alertness if needed. Although
hypnagogic experiences can occur in stage 1, less vivid
mental imagery is common.
• Although dreamlike, these images lack the unfolding,
sometimes bizarre details of a true dream.
Stage 2 NREM
• Stage 2 represents the onset of true sleep.
• Stage 2 sleep is defined by the appearance of sleep
spindles, brief bursts of brain activity that last a second
or two, and K complexes, single but large high-voltage
spikes of brain activity that periodically occur. Other than
these occasional sleep spindles, brain activity continues
to slow down considerably.
• Breathing becomes rhythmical. Slight muscle twitches
may occur. Theta waves are predominant in stage 2, but
large, slow brain waves, called delta brain waves, also
begin to emerge.
• During the 15 to 20 minutes initially spent in stage 2,
delta brain-wave activity gradually increases.
Stage 3 and Stage 4 NREM
• Stages 3 and 4 of NREM are physiologically very similar. Both
stages are defined by the amount of delta brain-wave activity. In
combination, stages 3 and 4 are sometimes referred to as slow-
• When delta brain waves represent more than 20 percent of total
brain activity, the sleeper is said to be in stage 3 NREM.
• When delta brain waves exceed 50 percent of total brain activity, the
sleeper is said to be in stage 4 NREM. During the 20 to 40 minutes
spent in the night's first episode of stage 4 NREM, delta waves
eventually come to represent 100 percent of brain activity. At that
point, heart rate, blood pressure, and breathing rate drop to their
lowest levels. However, his muscles are still capable of movement.
• The sleeper is approximately 70 minutes into a typical night's sleep
and immersed in deeply relaxed stage 4 NREM sleep. At this point,
the sequence reverses. In a matter of minutes, the sleeper cycles
back from stage 4 to stage 3 to stage 2 and enters a dramatic new
phase: the night's first episode of REM sleep.
• During REM sleep, the brain becomes more active, generating
smaller and faster brain waves. Visual and motor neurons in the
brain activate repeatedly, just as they do during wakefulness.
• Dreams usually occur during REM sleep. Although the brain is very
active, voluntary muscle activity is suppressed, which prevents the
dreaming sleeper from acting out those dreams.
• REM sleep is accompanied by considerable physiological arousal.
The sleeper's eyes dart back and forth behind closed eyelids-the
rapid eye movements. Heartrate, blood pressure, and respirations
can fluctuate up and down, sometimes extremely. Muscle twitches
occur. In both sexes, sexual arousal may occur, which is not
necessarily related to dream content.
• This first REM episode tends to be brief, about 5 to 15 minutes.
From the beginning of stage 1 NREM sleep through the completion
of the first episode of REM sleep, about 90 minutes have elapsed.
Beyond the First 90 Minutes
• Throughout the rest of the night, the sleeper cycles
between NREM and REM sleep. Each cycle lasts about
90 minutes on average, but the duration of cycles may
vary from 70 to 120 minutes.
• Usually, four more 90-minute cycles of NREM and REM
sleep occur during the night. Just before and after REM
periods, the sleeper typically shifts position.
• Stages 3 and 4 NREM, slow-wave sleep usually occur
only during the first two 90-minute cycles. As the night
progresses, REM sleep episodes become increasingly
longer and less time is spent in NREM.
• During the last two 90-minute sleep cycles before
awakening, NREM sleep is composed primarily of stage
2 sleep and periods of REM sleep can last as long as 40
Disrupting the sleep-wake cycle
• As with many other physiological processes, sleep is
linked to a 24-hour circadian rhythm and affected by
signals such as light and dark. The effects of disrupting
the sleep-wake cycle can be seen in jet lag, which is
characterized by fatigue, irritability, lack of alertness, and
• A person affected by jet lag feels like sleeping at the
wrong times of day. It has been found that the body
maintains a circadian sleep-wake rhythm even in the
absence of external cues like lightness and darkness,
although research subjects deprived of such cues
eventually adopt a 25-hour “day.”
• The “internal clock” that maintains this pattern is a
section of the brain called the supra chiasmatic nucleus
(SCN), located in the hypothalamus.
Disorders interfering with sleep
• Various disorders interfere with sleep. The most common is
insomnia, the inability to fall asleep or stay asleep. Nearly
one-third of all Americans are affected by some degree of
insomnia. Often associated with mental distress, insomnia is
treated with medication, psychotherapy, relaxation
techniques, or a combination of these methods.
• The medications most commonly prescribed are
benzodiazepines (Valium, Halcyon, Restoril) and barbiturates.
While they alleviate insomnia in the short run, these drugs
interfere with normal sleep patterns, and can lead to
increased tolerance and dependence.
• Researchers and clinicians have had success treating
insomnia with the hormone melatonin, a naturally occurring
substance related to sleep onset and secreted by the pineal
• Narcolepsy, a disorder characterized by sudden and uncontrollable
occurrences of sleep, afflicts 100,000 people in the United States.
This condition is genetically linked, and may be curable in the future.
Individuals affected by narcolepsy abruptly enter REM sleep states
during the daytime, collapsing and remaining immobile for a period of
time after awakening. Napping and stimulants have both been used to
treat this condition.
• Another disorder associated with sleep is sudden infant death
syndrome (SIDS), in which a healthy baby stops breathing during
sleep, fails to awaken, and suffocates. While the exact cause of SIDS
is unknown, researchers are attempting to identify and save at-risk
infants by studying the relationship between the disorder and sleeping
• In sleep apnea, a person repeatedly stops breathing while asleep but
awakes each time. The disrupted sleep that results from these
multiple awakenings leaves the sleeper fatigued and sleepy during the
• Night terrors are non-REM dream experiences from which the
sleeper never fully awakes and which he or she does not recall upon
awakening. This condition mostly occurs in children and can be
treated with hypnosis or medication in severe cases.
Chronic sleep problems
• An estimated 15 percent of Americans have
chronic sleep problems, while about 10 percent
have occasional trouble sleeping.
• Sleep disorders are listed among the clinical
syndromes in Axis I of the American Psychiatric
Association’s Diagnostic and Statistical Manual
of Mental Disorders.
• They may be either primary (unrelated to any
other disorder, medical or psychological) or
secondary (the result of physical illness,
psychological disorders such as depression,
drug or alcohol use, stress, or lifestyle factors,
such as jet lag).
• Sleep deprivation appears to be a precipitating factor for
seizures in some people with epilepsy. The reason why
this should be so is unclear. It may be due to
neurochemical or hormonal changes or it is possible that
the normal increase in protein synthesis that occurs in
sleep may be impeded, thereby diminishing cellular
repair mechanisms and rendering brain cells more open
to epileptic activity. However, sleep deprivation may also
be used by doctors to activate EEG abnormalities in
patients when a diagnosis of epilepsy is unclear.
• In conclusion, people whose seizures are triggered by
changes in sleep patterns should be advised to maintain
reasonably regular hours of retiring and awakening, to
obtain sufficient sleep, and to avoid shift work or other
causes of disrupted sleep-waking rhythms. There is not
need to exceed average hours of sleep to reduce the
chances of seizures occurring.
• Certain waking states, which are accompanied by marked
changes in mental processes, are considered states of altered
consciousness. One of these is hypnosis, a highly responsive
state induced by a hypnotist through the use of special techniques.
While the term “hypnosis” comes from the Greek word for sleep
(hypnos), hypnotized people are not really asleep. Their condition
resembles sleep in that they are relaxed and out of touch with
ordinary environmental demands, but their minds remain active
• Other characteristics of hypnosis include lack of initiative, selective
redistribution of attention, enhanced ability to fantasize, reduced
reality testing, and increased suggestibility. Also, hypnosis is often
followed by post-hypnotic amnesia, in which the person is unable
to remember what happened during the hypnotic session.
• Hypnosis has proven useful in preventing or controlling various
types of pain, including pain from dental work, childbirth, burns,
arthritis, nerve damage, and migraine headaches.
Degrees of hypnosis
• There are three degrees of hypnosis. Under light hypnosis, the
subject becomes sleepy and follows simple directions; under
deep hypnosis, the person experiences dulling of sensory
perception, similar to that of anesthesia.
• Under deep hypnosis, the subject can move about, open his or
her eyes, and can even undergo medical procedures with no
additional anesthetic. Magicians and illusionists use deep
hypnosis to make a subject behave in unusual ways, such as to
suspend the subject’s body between two chairs in a posture that
is completely stiff. The magician suggests that the subject’s body
become stiff and rigid, and the result is muscle tension powerful
enough to support the body completely.
• Many researchers contend that the key factor in hypnosis is the
subject’s willingness to cooperate with the hypnotist, combined
with the subject’s belief that hypnosis works. People who are
easily hypnotized are described as “suggestible”; in fact, if the
subject expects to be successfully hypnotized, it is much more
likely that he or she will.
• Hypnotic induction is the process by which hypnosis is
accomplished. In most situations, an individual performs the
induction on a willing subject. Classical hypnotic induction
involves a series of steps.
• First, sensory input to the subject is restricted, and the subject
is instructed to stop moving. Second, the subject’s focus of
attention is narrowed. This may be accomplished by asking
him or her to focus on a specific point of light or a spot on the
• Finally, the hypnotist begins a pattern of monotonous
• Doctors also employ hypnosis as a method of pain
management for chronic headaches, backaches, severe
burns, and during childbirth. In cancer treatment, hypnosis is
used to control the side effects of chemotherapy and as a
self-healing adjunct to chemotherapy.
• Hypnosis is also used for autoimmune diseases, sleep
disorders, and skin ailments, including warts and rashes.
Some surgeons use hypnosis in the operating room, not
only to reduce the amount of anesthesia patients need, but
also to lessen anxiety and postoperative swelling and
• A patient in an hypnotic trance can remain immobile for
extended periods of time, avoiding aggravation of the injury.
• Victims under a state of shock are also more responsive to
hypnotic induction. Dentists use hypnosis to complete dental
work on a relaxed patient without the need for anesthesia.
• A number of professional organizations offer training and
advanced training in hypnosis.
• Among these are the American Society of Clinical
Hypnosis, the American Board of Medical Hypnosis, the
American Board of Psychological Hypnosis, the
American Board of Hypnosis in Dentistry and the
American Hypnosis Board for Clinical Social Work. The
American Psychiatric Association, the American
Psychological Association, and the American Dental
Association have all endorsed the technique.
• Mental health professionals have used hypnosis to treat
sexual dysfunction, eating disorders, smoking and other
addictions, enuresis and thumb-sucking.
• In meditation, an altered state of consciousness is
achieved by performing certain rituals and exercises.
Typical characteristics of the meditative state include
intensified perception, an altered sense of time,
decreased distraction from external stimuli, and a sense
that the experience is pleasurable and rewarding.
• While meditation is traditionally associated with Zen
Buddhism, a secular form called Transcendental
Meditation (TM) has been widely used in the United
States for purposes of relaxation. It has been found that
during this type of meditation, people consume less
oxygen, eliminate less carbon dioxide, and breathe more
slowly than when they are in an ordinary resting state.