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SLEEP
Consciousness
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Awareness of everything that is going on
around you and things inside your head at any
given time
thoughts, sensations, and feelings
o needed to organize our behavior
One of the body’s biological rhythms
o Natural cycles of activity that our body
must go through
o Can be monthly (e.g. menstruation)
o Can be short (e.g. heartbeat)
o Daily (e.g. temperature, blood pressure)
o Sleep-wake cycle (circadian rhythm)
▪ Comes from the Latin word circa
(about) and diem (day)
▪ Takes about a day to complete
DIFFERENT STATES OF CONSCIOUSNESS
Waking Consciousness
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Encompasses the time we are awake
Thoughts, feelings, and sensations are clear and
organized
People feel alert
Altered States of Consciousness
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Differ from organized waking state
A shift in the quality or pattern of mental
activity
Fuzzy, disorganized, and bizarre thoughts
Increased alertness
o especially when under the influence of
a stimulant
Division of conscious awareness
o Can be dangerous (e.g. driving and
texting)
Two kinds of thought processes:
1. Controlled Processes
- Processes that require our attention to
a fairly high degree (driving, listening in
class, writing notes)
- Should only be done one at a time
- You can do an automatic process with
this at the same time
2. Automatic Processes
- Require far less than a conscious level
of attention (walking, combing your
hair)
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Responsible for the circadian rhythm
Contains the suprachiasmatic nucleus (SCN)
o Structure in the hypothalamus that
influences the release of melatonin
o Sensitive to changes in light
o Controls the pineal gland
o also controls body temperature
Melatonin
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Hormone
Secreted by the pineal gland
Suppresses the neurons that keep us awake and
alert
Used to treat jetlag
OTHER FACTORS THAT INFLUENCE OUR SLEEP:
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Serotonin
Body temperature
o Higher = alert
o When we’re asleep at night, our body
temperature is at its lowest
How much sleep is needed? It varies.
SLEEP
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Hypothalamus
The gentle tyrant (we try to fight it but we
eventually give in)
Adults – usually 7-8 hours
Old age interrupts sleep
Elderly – 6 hours
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Bladder capacity
Snoring
Sensitivity to light
Sleep Deprivation
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Microsleeps
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Brief sidesteps into sleep
Lasts only for a few seconds
Person is unaware
When you don’t sleep for a while and your body
is exhausted
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THEORIES OF SLEEP
A. Adaptive Theory
- Answers why we sleep at night
- Sleep is a product of evolution
- Our ancestors evolved different sleeping
patterns to avoid predators’ normal
hunting times
- In a safe place conserving energy while
predators are hunting at night
- Prey animals sleep for a shorter amount of
time in order to keep themselves safe
(gazelles sleep 4 hours)
- Predator animals sleep for a longer time
(lions sleep 15
hours a day)
B. Restorative Theory
- Answers why we need to sleep in the first
place
- Sleep is necessary to physical health
- Chemicals are replenished
- Excess chemicals that can be toxic are
removed
- Cellular damage is repaired
ASSOCIATION BETWEEN SLEEP AND MEMORY
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Physical changes when forming new memories
o Forming new neural connections
o Strengthened during sleep
o Sleep enhances synaptic connections
among neurons
o Sleep reduces activity of neurons
associated with forgetting
o (people who learn tasks before sleeping
perform better than if they don’t sleep)
o Sleep deprivation = poorer memory
retention
The loss of sleep
Serious consequences for mental and physical
functioning
Emotional symptoms
Common symptoms include:
o Fatigue
o Difficulty concentrating
o Memory problems
o Mood changes
o Paranoia
o Hallucinations
*We cannot make up for lost sleep
KINDS OF SLEEP
Rapid Eye Movement Sleep (R/REM)
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Eyes move rapidly
Relatively psychologically active type
o Our brains are active
Most dreaming takes place
Little to no moving
Energy conservation and memory consolidation
As the night progresses, REM sleep becomes
longer
o Sleep
thus
becomes
more
restorative/restful
Non-Rapid Eye Movement Sleep (N / NREM)
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Any stage that does not include REM
Spans from light sleep to restful sleep to deep
sleep
Body is free to move around
BRAINWAVES
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People have different brainwave activities
depending on the stage of sleep they’re in
electroencephalograph (EECG)
• Used to record brain activity as people
pass through different stages of sleep
1. Beta Waves
• Very small and fast
• Waves present when people are wide
awake and mentally active
2. Alpha Waves
• Slightly larger and slower
• Indicate state of relaxation
drowsiness
3. Theta Waves
• Slower and larger
• Indicate early stages of sleep
4. Delta Waves
• Largest and slowest waves
• Deepest stages of sleep
STAGES OF SLEEP
or
g. Bedwetting, sleep walking, night terrors
h. After N3, a person will go back to N2,
then REM
4. R: Rapid Eye Movement/Paradoxical Sleep
a. Eyes move fast in different directions
b. Brain waves resemble beta waves
c. Breathing patterns become irregular
d. Limbs are paralyzed
e. Body temperature increases
f. Bizarre tales and wild dreams when
awoken
g. Cycle repeats after REM
h. 90% of dreams occur here
i. People can also dream in other
N stages
ii. Dreams in REM are more vivid,
more detailed, longer, more
bizarre
i. Sleep paralysis
j. REM Behavior Disorder (RBD)
i. Failure of brain mechanisms to
inhibit voluntary muscles
- Each stage is 90 minutes long *whole cycle is 90 min.
PURPOSES OF R SLEEP AND N SLEEP
1. N1: Light Sleep
a. Very light sleep
R Sleep
b. Theta wave activity increases
c. Won’t believe they were asleep
- Emotionally stressful day increases time in REM
d. Hypnogogic images or hallucinations
- A way to deal with stresses and tensions of the
e. Hypnic jerk
day
- REM Rebound
2. N2: Sleep Spindles
o Increased amounts of REM sleep after
a. Brief bursts of activity lasting only a
being deprived of REM on earlier nights
second or two
o Depressants like sleeping pills and
b. Slowing down of brain waves
alcohol decrease REM sleep, leading to
c. Heart rate slows
fatigue
d. Shallow and irregular breathing
- Adults only spend 20% of their sleep in REM
e. May help stimulate neural areas in
- Babies spend 50% of their sleep in REM
which recent memories have been
o Babies form new neural connections
stored
N Sleep
f. Aware of having been asleep
- Physically demanding day increases N sleep
3. N3: Slow-wave sleep (SWS)
- Recovery of the body
a. Delta waves appear
FACTORS THAT AFFECT SLEEPING PATTERNS
b. Deepest stage of sleep
c. Hard to awaken
- Stress levels
d. Confused and disoriented when awoken
- Low mood and depression
e. Time when body growth occurs
- Worry or anxiety
f. Boys sleep more deeply than girls
- Physical health conditions
because of testosterone
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Medications
Worry about sleep
*Alcohol and prescription medicine
Assist in stage 1 and 2 of sleep
Degrade restoration, stage 3, and REM sleep
SLEEP DISORDERS
Nightmares
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Bad dreams
Can be terrifying
Occur during R stages
Children have more nightmares
o They spend more time in REM
Usually can vividly remember what happened
Night Terrors
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Rare disorder
State of panic experienced while asleep
Sit up, scream, run around, flail at unseen
attacker
Feel unable to breathe
Occur during N stages
Most people don’t remember what they were
dreaming about
Sleep Apnea
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Sleepwalking/Somnambulism
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Episodes of walking or moving around in one’s
sleep
Sit up, walk around the house, eating, get into a
car
Partly hereditary
Can sometimes be outgrown
Preventing sleep loss regulates sleepwalking
Narcolepsy
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Insomnia
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Inability to get to sleep, stay asleep, or get
quality sleep
Psychological causes
o Overthinking
o Anxiety
o trying too hard to sleep
Physiological causes
o Ingesting too much stimulants
o Indigestion
o Aches and pains
Person stops breathing for more than 10 seconds
Followed by a gasping reflex
Can cause poor sleep quality, depression, and
heart problems
Dealt with by:
o Losing weight (obesity causes apnea)
o nasal opening devices
o nasal sprays to shrink nasal tissues
o Continuous Positive Airway Pressure
(CPAP) device
Person falls into REM sleep during the day
Excessive daytime sleepiness
Uncontrollably falling asleep at inappropriate
times and places
Occurs especially when experiencing strong
emotions
May occur many times without warning
Sometimes might have cataplexy
o Sudden loss of muscle tone
o Falling asleep while standing up will
cause them to fall
DREAMS
Freud’s Interpretation of Dreams:
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Examine dreams to get to early memories
Dreams represent conflicts, events, and desires
Dreams are wish fulfillment
o Things we didn’t get to say or do in
wakefulness
Freud’s Two Types of Content in a Dream:
1. Manifest Content
o Actual or obvious content
2. Latent Content
o Hidden meaning
o Expressed in symbols
Activation-Synthesis Hypothesis
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Dreams are created by higher centers of the
brain to explain the activation by the brain stem
during REM sleep periods
Dream is another kind of thinking
o Thinking is less realistic because stimuli
is not external but from within person
o Brain searches memories and past
experiences to explain the signals
o Frontal lobes shut down during
dreaming, leading to bizarre dreams
Brain functions during waking consciousness:
o Pons send signal to the cortex
o The association areas of cortex interpret
those signals as seeing, hearing, etc.
o Results in an experience of reality
Brain functions during sleep:
o Pons send random signals to the cortex
▪ Not attached to external stimuli
o Brain needs to interpret the signals
▪ Will synthesize an explanation
for the cortex’s activation
Activation-Information Mode
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Revised version to reflect the meaning of our
dreams
Dreams are influenced by information accessed
during waking hours
When our brain is trying to make up an
explanation for activation, it will use your
experiences for the past few days (more recent
memories)
Some Facts:
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Most dreams reflect events that occur in
everyday life
Most people dream in color
o people who grew up with black and white
media sometimes dream in black and white
There are gender differences in the content of
dreams
o Men tend to dream about other men
o Men report more sexual and more
aggressive dreams
o Women report being victims of
aggression in their dreams
o Women dream of males and females
equally, people they know, personal
experiences, family issues