Consciousness
 The process by which the
brain creates a model of
internal and external
experience
 The state of being
conscious; awareness of
one's own existence,
sensations, thoughts,
surroundings, etc.
 A great mystery to many….
Why a mystery?
 Subjective
 Psychologists felt it needed to be
studied objectively. (How do you prove
you have a conscious?)
 Recent advances in new technology
allowed scientists to scan brain.
 Cognitive neuroscience: many
scientists from various fields who are
interested in the connection between
mental process and the brain.
Tools for Studying Consciousness
 MRI, PET, EEG: Can see what regions of the brain are
active during various mental tasks.
http://mental rotation
 Mental rotation: Experiment in which Roger Shepard
and Jacqueline Metzler (1971)wanted to see if people
could “turn things over in their minds”
Tools to Study Consciousness
 Zooming in with the mind: Stephen
Kosslyn (1976) found that we use our
conscious mind to zoom in on details of
our mental images.
 The smaller the details the longer it took
the person to respond.
 He concluded they needed extra time to
make a closer examination of their images.
The Conscious and Non-conscious
Mind
 William James: compared to a
flowing stream that carries ever
changing sensations, perceptions,
thoughts, memories, feelings ,
motives and desires.
 “Stream of Consciousness”
 Freud: Compared to an Iceberg.
Freud
 Psychoanalytical theory said that
we repress all of these unacceptable
desires and thoughts in our
unconsciousness.
 If allowed to breakthrough it would
cause much anxiety.
 New research says that our
conscious mind works with our
non-conscious mind rather than
against it as Freud suggested. (2
track system)
Conscious Mind
 It restricts our attention. It keeps our brain from
being overwhelmed
 It provides a “meeting place” where sensation can
combine with memory, emotions and motivations.
(reading and words on a page)
 Allows us to create a mental model of the world that
we can manipulate.
Non-conscious Mind
 Preconscious: Information
that can be recalled with
ease when we call attention
to it. Otherwise it just “sits”
in our mind.
 Example “What did you do
this weekend?” or “What
song were you listening to
earlier?”
 Unconscious: cognition occurring
without awareness that can consists
of many levels.
 Can range from things that run on
auto pilot like driving home from
school to other things that
influence our behavior.
 Example:
D E F_ _ _
Consciousness - Crash Course Psychology #8
moonwalking bear
Cycles in everyday Life
 Sleep cycles and biological
clocks.
 Daydreaming, Sleep and
Dreaming all occur because
of these cycles.
Daydreaming
 Attention turns toward
memories, expectations
and desires.
 Can be healthy because it
allows us to plan, and
solve problems.
 Can also be unhealthy
when we focus only on
what were not supposed
to think about….the
white bear example.
Sleep
 Circadian rhythm: biological
clock that sets functions such
as metabolism, heart rate,
body temp and hormonal
activity.
 Located or operates from the
hypothalamus
 If circadian rhythm is thrown
off, it can affect how you feel
and behave.
Phases of Sleep
 REM sleep: Occurs approx.
every 90 min. marked by
bursts of eye movements.
Often associated with
dreaming. This is where
sleep paralysis occurs.
 NREM sleep: the interim
periods marked by no rapid
eye movement and when
the deepest sleep occurs.
Sleep Cycle
 Studied with an EEG
 Stage 1: similar to being awake with both theta (slow)
and beta (fast) waves.
 May experience fantasy like images similar to
hallucinations.
 Stage 2: Shows short bursts of fasts electrical activity.
 These waves are sometimes called sleep spindles
 Usually last about 20 min
 Stages 3 & 4: Deepest sleep, heart rate and breathing
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slow down as well as brain waves.
Delta waves appear.(large slow waves)
Deepest point about 30 min after beginning sleep
cycle.
Stage 4 ends when electrical activity increases.
Sleeper starts back into sleep cycle starting with stage
3, then 2 etc. (going backwards)
 Once stage 1 is reached, sleeper enters REM for the first
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time but only for a few minutes. (in beginning)
Average nights sleep = 4-6 times through sleep cycle
Each time you go through REM, it becomes longer while
stages 3 & 4 become shorter.
Each cycle is about 90 minutes long.
Brain waves are similar to stage 1 but your heart rate
rises, your breathing becomes irregular and eyes dart
back and forth.
More on REM
 Brain’s motor cortex is active but your brain stem
blocks the messages. You are essentially paralyzed
 Sleep paralysis: immobility that lingers as you awaken
from REM sleep
 Paradoxical sleep (REM) body is internally aroused,
with waking like brain activity but calm and peaceful
Safety in Numbers?
 Why would
communal sleeping
provide added
protection for those
whose safety depends
on vigilance, such as
soldiers?
Functions of Sleep
 Aids in mental functioning,
memory and problem solving.
 To recuperate: Restores energy
and repairs cells
 Sleep feeds creative thinking
 Sleep supports growth
 Athletic performance: faster
reaction times, more energy
and greater endurance.
How much do we need?
 Genetics plays a role.
 Linked to our personal
characteristics and habits.
 Exercise also influences
stage 4 sleep.
 Sleep duration and sleep
cycles may change
throughout life span.
 Less REM time as we age. : (
Light and Sleep
 Light signals the
superchiasmatic nucleaus
(SCN)in hypothalamus.
 This controls pineal gland
and its production of
melatonin ( a sleep inducing
hormone)
 Light therefore disrupts our
sleep pattern (cellphones,
lights, TV etc.)
Sleep Debt
 Average adult settles into a
pattern of about
8 ½ hours.
 Americans are sleep deprived
and most don’t realize it.
 Circadian clock makes us seem
alert when in fact we are sleep
deprived.
 However, you are never as alert
as you could be if you had a
good nights sleep.
Sleep Deprivation
 69% of all college students were sleep deprived (2009)
 28% of high school students fell asleep in class at least
one per week. (2006)
 Correlation with an increased risk of depression
 Makes you gain weight. Increases ghrelin and
decreases leptin
 Weakens our immune system (viral infections and
cancer)
 Sleep deprivation can greatly
effect cognitive and motor
functions.
 Study done on group of
volunteers in which half
were given enough alcohol to
make them legally drunk.
The other half were not
allowed to sleep for 24 hours.
 Conclusion: Both performed
similar on tests of thinking
and coordination.
Dreaming
Dreams occur every night
most often during the REM
stage.
We know there are parts of
the brain that are
associated with dreaming
especially parts in the
brain stem.
But why do we dream?
Meaningful Events…
 Sigmund Freud developed the most
comprehensive theory of dreams
ever developed
 But no real scientific evidence to
back it up.
 Dreams represent “the royal road to
the unconscious” and it contains
clues to our hidden mental life.
 The Interpretation of Dreams (1900)
Freud’s view of Dreams
 Dreams serve 2 main functions.
To guard sleep which means our
dreams disguise disruptive thoughts
with symbols. Dreams allow us to
relieve tensions created during the
day.
2. Sources of wish fulfillment allowing
the dreamer to work through the
unconscious desires.
1.
 Manifest Content: This is the dream’s story line.
 Latent Content: the symbolic meaning of the dream.
 Therapists would look for clues in the manifest content
of the dream that would relate to the latent content.
 Research states that manifest content is connected to
our waking life.
 By interpreting your symbols, the latent content, you
can make connections to your everyday life.
 BUT no scientific proof for latent content.
Culture, Gender and Age
 Freud's views have also been challenged in that he was not
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always careful in his research. (confirmation bias)
Example: Freud said boys dream of conflict with their
fathers but had no evidence to prove this conflicted
existed.
Content of dreams varies with age, gender and culture.
Children dream of animals more
College students dream of small animals more
Dreams reflect life events that important to the dreamer.
(Rosalind Cartwright, 1977)
Culture
 Ghana: attacks by cows
 Americans: Being naked
 Mexican Americans:
Images of death
 Dreams and recent
experience: dream
content connects
with recent
experience.
 Dreams and
cognition: Dreams
may help us
remember. It weaves
our new experiences
with old ones in
order to help us
remember.
Random Activity
 Activation synthesis theory: dreams are a result of the
sleeping brain trying to make sense of the
spontaneous bursts of activity. (biopsychological)
 Energy sweeps over cerebral cortex, then the sleeper
experiences impressions of sensation, memories,
emotion, motivation etc.
 None of it is really is connected but the brain tries to
make sense of it by creating a story.
 Proponents of this theory, however, believe it to have
some psychological connection.
Creativity
Sleep Disorders
 What do all 3 of the following have
in common?
1. Three mile Island
2. Exxon Valdez
3. Chernobyl
Insomnia
 Most common sleep disorder
 1 out of 10
 Chronic inability to fall asleep
 Caused by a variety of
psychological, environmental
and biological factors.
 Medications may help but risk
disrupting the sleep cycle by
cutting short the REM stage.
Sleep Apnea
 Sleep disorder in which person
stops breathing many times
while asleep.
 1 out of 20
 Major symptoms include
snoring and daytime sleepiness.
A feeling of never having a
restful night’s sleep can also be
a symptom.
 May be a cause of SIDS in young
infants.
Night Terrors and Sleep
walking(Somnamublism)
 Both occur in stage 3& 4 of
sleep cycle.
 Both occur in young children
and most outgrow as adults.
 Underdeveloped nervous
system may be cause. Fatigue
and anxiety may also play a
role.
 Both are usually forgotten by
sleeper.
Narcolepsy
 Rare sleep disorder in which
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person falls asleep suddenly and
goes right into REM stage.
1 out of 2000
Accompanied by Cataplexy
(sudden loss of muscle control)
Excitement seems to cause a
person to have a narcoleptic
episode.
Has a biological basis.
Absence of a neurotransmitter,
orexin, that is linked to alertness
living with narcolepsy
Crash Course #9
 To Sleep, Perchance to Dream