Chapter 5: Variations in
Consciousness
Consciousness: Personal Awareness
• Consciousness
– Includes:
• Awareness of external events
• Your awareness of internal sensations
• Your awareness of the uniqueness of
having these experiences
• Your awareness of the thoughts of these
experiences
Consciousness: Personal Awareness
• Levels of awareness
• James 1902 – stream of consciousness- an
endless flow of ideas
– Freud – unconscious- was one of the first
theorists to recognize that consciousness is not an
all or none phenomenon…rather there are levels
of awareness
• Sleep and dreaming researchers also showed
that awareness is different during sleep and
dreaming, but mental processes occur that are
quite similar to waking thought and surprisingly
sophisticated
The Electroencephalograph:
A Physiological Index of Consciousness
• EEG – monitoring of brain electrical activity
• Brain-waves: across large areas of the cerebral
cortex. It is basically a physiological index of
consciousness
– Amplitude (height)
– Frequency (cycles per second)
• Beta (13-24 cps): alertness and problem
solving
• Alpha (8-12 cps) resting and relaxation
• Theta (4-7 cps): low alertness and sleep
• Delta (<4 cps): deep, dreamless sleep
Table 5.1 EEG Patterns Associated with States of Consciousness
p. 178
Biological Rhythms and Sleep
• Circadian Rhythms – 24 hr biological cycles
– These daily cycles are particularly
important in the regulation of sleep, but
also in the regulation of temperature, blood
production, hormone production, and other
bodily processes.
– Our bodies are set-up on a 24.2 hour sleep
cycle
Fig. 5-3, p. 177
Biological Rhythms and Sleep
• Physiological pathway of the biological clock:
– The pathway for regulation of the human biological
clock appears to be based in light levels, which go
from the eye to an area of the brain called the
suprachiasmatic nucleus (in the hypothalamus).
– This nucleus tells the pineal gland to secrete
melatonin, a hormone that adjusts biological
clocks
• Light levels  retina  suprachiasmatic
nucleus of hypothalamus (in the
hypothalamus) pineal gland  secretion of
melatonin
Biological Rhythms and Sleep
• Sleep and Work (or school for you)
– Your body likes a set schedule
– Shift rotation is hard on the body and leads
to more fatigue, lower production, and
more accidents
• 40% rise in cardio. Disease
• Irregular menstrual cycles
• increase in premature deaths
• Lower fertility
Biological Rhythms and Sleep
• Melatonin and circadian rhythms
– Melatonin supplements are sold in the U.S. as
nutritional supplements, but many researchers
worry that people are taking too high doses of this
substance, when long-term effects have not been
tested.
– Research shows that may be helpful in the
treatment of jet lag, but timing is very important
and hard to get right. Studies also show that
melatonin may be useful as a mild sedative, more
so in the daytime than at night, when melatonin
levels are naturally higher
Sleep/Waking Research
• Instruments:
– Electroencephalograph – brain electrical
activity
– Electromyograph – muscle activity
– Electrooculograph – eye movements
– may also record heart rate, breathing rate,
temperature, etc., as well as videotape the
person sleeping through a window
• people get used to the wires and
cameras after only one night
Sleep Stages: Cycling Through Sleep
• Stage 1: brief, transitional (1-7 minutes)
– moves from predominately alpha waves,
when the person is just about to fall asleep,
to more theta activity
– Hypnic jerks, those brief muscle
contractions that occur when one is falling
asleep, occur in stage 1 sleep.
• Stage 2: (10-25 minutes)
– characterized by more mixed brain wave
activity with brief bursts of higherfrequency brain waves, called sleep
spindles
Sleep Stages: Cycling Through Sleep
• Stages 3 & 4: slow-wave sleep (30 minutes)
– characterized by low frequency delta
waves; 30 minutes to reach stage 4, and
usually people stay there for about 30
minutes
• Then the cycle reverses. When stage 1
should be next in line in the cycle, something
interesting happens…rapid eye movement
(REM) sleep begins.
– REM sleep was accidentally discovered by
Nathaniel Kleitman in the spring of 1952
Sleep Stages: Cycling Through Sleep
• Stage 5: REM
– EEG that looks awake and alert…and by rapidly
moving eyes behind the lids, an irregular pulse
and breathing rate, and loss of muscle tone
– someone awakened from REM sleep often reports
vivid dreaming
– Developmental differences in REM sleep:
• Infants spend much more time in REM than do
adults.
• During adulthood, sleep changes continue with
the percentage of slow-wave sleep declining
and the percentage of time spent in stage 1
increasing
Figure 5.5 An overview of the cycle of sleep
The Neural Bases of Sleep
• Brain Structures:
– Ascending reticular activating system
• a system of afferent fibers running
through the reticular formation that
influence physiological arousal. When
these fibers are cut, animals will sleep
continuously. If they are stimulated,
arousal and alertness result
– Pons (REM sleep), medulla, thalamus,
hypothalamus, limbic system
The Neural Bases of Sleep
• Neurotransmitters:
– Acetylcholine and serotonin (sleep itself)
– Also norepinephrine, dopamine, and GABA
(involved in arousal and the course of
sleep)
• Basically, no one center or chemical is
at work; sleep is rather an interplay of
many neural centers and
neurotransmitters.
Figure 5.7 The ascending reticular activating system (ARAS)
Why Do We Sleep?
• Hypothesis 1:
– Sleep evolved to conserve organisms’
energy
• Hypothesis 2:
– Immobilization during sleep is adaptive
because it reduces danger
• Hypothesis 3:
– Sleep helps animals to restore energy and
other bodily resources
Sleep Deprivation
• Complete deprivation
– Sleep deprivation studies indicate that
people can function surprisingly well when
sleep deprived; although effects on mood
and performance are present, these are
modest
– 3 or 4 days max
Sleep Deprivation
• Partial deprivation or sleep restriction (very
common)
– impaired attention, reaction time, coordination,
and decision making
– accidents: Chernobyl, Exxon Valdez
• Selective deprivation
– When researchers wake subjects up whenever
they go into REM sleep, thus depriving them of
this one particular stage, they find that soon, the
person will try to go back into REM faster
– REM and slow-wave sleep: rebound effect
Featured Sleep Study
• College kids and standardized tests (both
intelligence and moods)– What were the results?
Figure 5.9 Effect of sleep deprivation on cognitive performance
Featured Study
• Those who were deprived of sleep did much
worse, but predicted they did much better
(and their attitudes/moods were still good)…
Sleep Problems
• Insomnia – trouble falling asleep, trouble
remaining asleep, and persistent early
morning awakening.
– Difficulty falling asleep is most common
among young people, while early morning
awakening and trouble staying asleep are
more common among middle-aged and
elderly people
– 34-35% of adults report problems with
insomnia and about 15-17% have severe
or frequent insomnia
– 50% more common in women than in men
Sleep Problems
• Narcolepsy – falling asleep uncontrollably
during normal waking hours
– person with Narcolepsy goes directly into
REM sleep
• Sleep Apnea – reflexive gasping for air that
awakens
– the person literally stops breathing for 15 to
60 seconds…can cause heart and lung
damage
Sleep Problems
• Nightmares – anxiety arousing dreams REM
• Night Terrors – intense arousal and panic NREM
• Somnambulism – sleepwalking
Figure 5.12 Sleep problems and the cycle of sleep
Figure 5.11 The vicious cycle of dependence on sleeping pills
Dreams and Dreaming:
Content and Significance
• Dreams –
– mental experiences during REM sleep that
are often based in vivid imagery, have a
storylike quality, are often bizarre, and
seem real to the dreamer
– people dream in non-REM too, although
the dreams are less story-like and vivid in
imagery, recent research shows that
content is usually not bizarre, and that
dreamers are often aware that they are
dreaming
Dreams and Dreaming:
Content and Significance
– Content usually familiar
– Common themes: include things like falling, being
pursued, trying repeatedly to do something,
school, sex, being late, eating, being frightened,
etc
• Children’s dreams appear to differ from those
of adults, with preschool children reporting
bland images with no story lines when awoken
from REM sleep (if they recall dreaming at all –
children under the age of 9-11 report dreaming
only 20-30% of the time when awoken from
REM sleep, as opposed to an adult’s 80% of
the time).
Dreams and Dreaming:
Content and Significance
• Between 5 and 8, children begin to
report dream narratives, but these are
not well developed. Adultlike dreams
develop at around 11-13, suggesting
that dreaming is a cognitive ability that
develops gradually.
– Waking life spillover – day residue- Freud
said that the contents of waking life tend to
spill into dreams; he called this day residue
• Western vs. Non-Western interpretations
Figure 5.14 Three theories of dreaming
Hypnosis: Altered State of Consciousness
or Role Playing?
• Hypnosis = a systematic procedure that
increases suggestibility- as well as relaxation,
narrowed attention, and enhanced fantasy.
• Hypnotic susceptibility: individual
differences- 10% of people are especially
easy to hypnotize, 10% especially difficult
• Susceptibility linked to higher levels of
absorption in a task and in a person’s
imaginativeness…greatly depends on
expectations.
Hypnosis: Altered State of Consciousness
or Role Playing?
• Effects produced through hypnosis:
– Anesthesia
– Sensory distortions and hallucinations
– Disinhibition
– Posthypnotic suggestions and amnesia
• Researchers argue about whether hypnosis is really
an altered state of awareness or if it is simply people
doing what they think they are supposed to do when
they are hypnotized…the dissociation hypothesis
holds that hypnosis splits consciousness into two
streams…divided consciousness
Meditation
• Meditation = practices that train attention to heighten
awareness and bring mental processes under greater
voluntary control
– Some of the most widely practiced forms of
meditation are yoga, Zen, and transcendental. All
three of these are rooted in Eastern religions;
however, many who meditate do so separately
from religious practice
– Effects of meditation include decreased heart rate,
respiration rate, etc., and a relaxed EEG, with
predominant theta and alpha rhythm patterns
Meditation
• Yoga, Zen, transcendental meditation (TM)
– Potential physiological benefits
• Similar to effective relaxation procedures
• research using the CT scan to track
blood flow in the brain in experienced
Tibetan Buddhist meditators shows high
activity in the prefrontal cortex (an area
important for focused attention) and low
activity in parts of the parietal lobe that
are known to process information about
the body’s location in space
Psychoactive drugs
• Psychoactive drugs: modify mental, emotional, or
behavioral functioning…
• Recreational drug use: pleasurable alterations in
consciousness.
• Narcotics (opiates) – pain relieving; morphine,
codeine, Demerol, and methadone…high doses
produce an overwhelming sense of euphoria
• Sedatives – sleep inducing; barbiturates…downers
• Stimulants – increase CNS activity; caffeine and
nicotine, as well as much stronger drugs such as
cocaine and amphetamines
Psychoactive drugs
• Hallucinogens – distort sensory and
perceptual experience; Hallucinogens such
as LSD, mescaline, and psilocybin
• Cannabis – produce mild, relaxed euphoria;
Cannabis is the hemp plant from which
marijuana, hashish, and THC
• Alcohol – produces relaxed euphoria,
decreases in inhibitions
• MDMA – produces a warm, friendly euphoria;
ecstasy
Table 5.3 Psychoactive Drugs: Tolerance, Dependence, Potential for Fatal Overdose, and Health Risks
Drug Effects
• Tolerance: you need more of the drug to gain
the same pleasure
• Physical Dependence: must take the drug to
avoid withdrawal symptoms
• Psychological Dependence: must take the
drug to satisfy mental and emotional cravings
• Many physiological and mental symptoms:
vary based on the type of drug