CHAPTER6: STATES OF CONSCIOUSNESS
I. The Puzzle of Consciousness
1. Definition: Defined as our momenttomoment awareness of ourselves and our environment.
a) Subjective and private: nobody knows what you feel or how you experience things
b) Dynamic (everchanging): your states change throughout the day
c) Self reflective and central to our sense of self
3. Consciousness is intimately connected with the process of selective attention.
4. Forms of consciousness
a) Some occur spontaneously: Daydreaming; drowsiness; dreaming
b) Some are physiologically induced: Hallucinations; orgasm; food or oxygen starvation
c) Some are psychologically induced: Sensory deprivation; hypnosis; mediation
B. Measuring States of Consciousness
1. Most common measure: selfreport (what do feel)
2. Studied by EEG (sleep)
a) Brain and consciousness: finding and debates
• Finding: Some are “unconscious” patients have brain responses to conversation
• Implication: Don’t judge a book by its cover when it comes to consciousness
• Debate » One View: Synchronized, coordinated brain activity generates consciousness, or at
least is a sign that conscious activity is occurring
3. Behavioral tasks (performance on a task) C. Levels of Consciousness: Psychodynamic and Cognitive Perspectives
1. The Cognitive Viewpoint
a) Controlled versus automatic processing
• Controlled or effortful processing: To focus your attention (voluntary)
• Versus automatic processing: Little or no conscious effort
• Controlled is more flexible: When learning more open to doing things other ways
(possible benefits: not having to think about everything we do all at once )
b) Divided attention
• People can divided their attention because of automatic processing
• If 2 or more activities require the same mental process, we aren’t so good at either task.
2. The Emotional Unconscious
3. The Modular Mind
II. Circadian Rhythms: Our Daily Biological Clocks
1. Circadian rhythms are our daily biological cycle. A bodily rhythm that occurs over a 24hour period; the
2. Every 24 hours body temp., certain hormones, and bodily functions undergo a rhythmic change that
affects our mental alertness and gets us ready to sleep and wake.
3. Regulated by the suprachiasmatic nucleus (the SCN is the brain’s clock) in the hypothalamus, which
responds to light and triggers the pineal gland to decrease melatonin.
A. Keeping Time: Brain and Environment
1. Suprachiasmatic Nucleus
a) SCN nuclei is located in the hypothalamus and is the brain’s clock.
b) The neurons here have cycles of activity and inactivity; link to pineal gland that produce melatonin
(relaxer). c) During the day, the SCN neurons are active and reduce melatonin production.
d) At night the neurons are inactive allowing melatonin to increase.
e) Environment Helps to Keep SCN Neurons on a 24 Hour Clock
2. Early Birds and Night Owls
B. Environmental Disruptions of Circadian Rhythms
1. Seasonal Affective Disorder (SAD)
a) Controversial disorder in which a person experiences depression during the winter and an
improvement of mood in the spring
b) Treatments may involve phototherapy or exposure to fluorescent light
c) Inconsistent findings with respect to prevalence and effectiveness of treatments
III. Sleep and Dreaming
Why do we sleep?
Protective role in human evolution
Brain restoration and repair of damaged neurons
Store and rebuild memories of day’s experiences
Promotes creative problem solving
Encourages growth through pituitary gland secretion of growth hormone
A. Stages of Sleep
1. Stage 1 through stage 4
a) Stage 1
• When you are relaxed and drowsy your brainwave pattern shows alpha waves.
• Then they become more irregular and slower theta waves increase. • You are now in stage 1, a form of light sleep from which you can easily be awakened.
• You will probably spend just a few minutes (or less) in stage 1, during which time some
people experience images and sudden body jerks.
b) Stage 2
• As sleep becomes deeper, sleep spindles—periodic one to twosecond bursts of rapid
brainwave activity—begin to appear.
• Sleep spindles indicate that you are now in stage 2.
• Your muscles are more relaxed, your breathing and heart rate are slower, and you are harder
• Sleep deepens as you move into stage 3, marked by the regular appearance of very slow and
large delta waves.
d) Stage 4
• As time passes, they occur more often, and when delta waves dominate the EEG pattern,
you have reached stage 4.
• Together, stage 3 and stage 4 are often referred to as slowwave sleep.
• Your body is relaxed, activity in various parts of your brain has decreased, and you are hard
• After 20 to 30 minutes of stage 4 sleep, your EEG pattern changes as you go “back through”
stages 3 and 2, spending a little time in each.
• Overall, within 60 to 90 minutes of going to sleep, you will have completed a cycle of stages
123432. At this point, a remarkably different sleep stage ensues.
2. REM Sleep
a) Dreams occur during rapid eye movements [REM sleep].
b) REM occurs about 90 minutes after sleep onset. c) The first period lasts 10 minutes.
d) With each episode REM sleep gets longer and the final episode can last an hour. Brain waves
similar to wakefulness.
e) The eyes move rapidly in different directions, intense dreaming as a results of brain activity but you
f) So it is a combo of brain excitement and muscular immobility.
B. Getting a Night’s Sleep: Brain and Environment
1. Dreams: Unfolding sequences of thoughts, perceptions, images, and emotions that typically occur
during REM sleep; notable for fantastic imagery, discontinuities, incongruities that the dreamer
delusionally accepts, but has later difficulty recalling.
a) Four or five dreaming episodes per night
b) Longest episodes occur during longest REM stages, typically early morning
c) Dependent on brain activity related to REM sleep
C. Sleep Over the Life Span (How Much Do We Sleep?)
1. Shorter sleep cycles in infancy. Sleep 17 hours a day 50% REM
2. 90minute cycle emerges by age 5
3. From childhood to late adulthood, total sleep time decreases
4. 1520 year olds sleep average of 8.5 hours a day and the elderly average under 6 hours.
5. Time spent into stages 3 and 4 declines and by late adulthood we get little stage slow wave sleep.
D. Sleep Deprivation
1. The Effects of Sleep Deprivation
b) Impairment of concentration, creativity, communication
c) Can lead to obesity, hypertension, suppressed immune system d) Can lead to irritability and slowed performance
E. Why Do We Sleep?
1. Benefits of Sleep
a) Memory consolidation: Process by which the synaptic changes associated with recently stored
memories become durable and stable, causing memory to become more reliable.
b) May also enhance problemsolving abilities
2. Sleep Loss Effects by Body System
a) Brain: Diminished attentional focus and memory consolidation, and increased risk of depression.
b) Immune system: Suppression of immune cell production and increased risk of viral infection, such
c) Fat cells: Increased production and greater risk of obesity.
d) Joints: Increased inflammation and arthritis.
e) Heart: Increased risk of high blood pressure.
f) Stomach: Increased hungerarousing ghrelin and decreased hungersuppressing leptin.
g) Muscles: Reduced strength, and slower reaction time and motor learning.
3. Consequences of Sleeplessness
a) Chronic sleep deprivation
• Increases cortisol levels which can impair neurons involved in learning & memory.
• The average sleepdeprived person function only as well as someone in the bottom 9% of non
b) Chronic insomnia
• Difficulty falling or staying asleep (about 10% of