"I love sleep. My life has a
tendency to fall apart when I'm
awake, you know?”
- Ernest Hemingway
Biological Rhythms
Annual Cycles: seasonal variations (bears
hibernation, seasonal affective disorder)
28 day cycles: menstrual cycle.
24 hour cycle: our circadian rhythm
90 minute cycle: sleep cycles.
Sleep:
Sleep and Dreams
periodic, natural, reversible loss of consciousness
Sleep
Laboratories
around the
world are just
beginning to
understand
sleep and
dreams.
Sleep Stages
Measuring sleep: About every 90 minutes, we
pass through a cycle of five distinct sleep stages.
Hank Morgan/ Rainbow
4
Sleep Stages 1-2
During early, light sleep (stages 1-2) the brain
enters a high-amplitude, slow, regular wave form
called theta waves (5-8 cps). Stage 1 is where we
experience hypnagogic sensations. In Stage 2,
sleep spindles appear.
Theta Waves
5
Sleep Stages 3-4
During deepest sleep (stages 3-4), brain activity
slows down. There are large-amplitude, slow
delta waves (1.5-4 cps).
6
REM Sleep
After reaching the deepest sleep stage (4), the sleep cycle
starts moving backward towards stage 1. Although still
asleep, the brain engages in low- amplitude, fast and regular
beta waves (15-40 cps) much like awake-aroused state.
A person during this sleep exhibits Rapid Eye Movements
(REM) and reports vivid dreams. Muscles are relaxed.
Sleep Stages – one more time
Typical Night’s Sleep
Why do we sleep?
We spend one-third of our lives sleeping.
If an individual remains awake for several
days, they deteriorate in terms of immune
function, concentration, and accidents.
• nutrition and exercise are not the only
foundational elements of well-being
• Without healthy sleep, an aspect much less
thought about on anything beyond a basic
level, overall health is utterly compromised as
good nutrition and exercise are much harder
to achieve in a meaningful way
The Triumvirate
of Health

Sleep Theories
1.
2.
3.
4.
5.
Sleep Protects: Sleeping in the darkness when
predators were about and it was hard to see dangers
helped keep our ancestors out of harm’s way.
Sleep Recuperates: Sleep helps restore and repair brain
tissue.
Sleep Helps Remembering: Sleep restores and rebuilds
our fading memories.
Sleep Helps Creative Thinking: After “sleeping on” a
problem, people solve it more insightfully
Sleep and Growth: During sleep, the pituitary gland
releases growth hormone. Older people release less of
this hormone and sleep less.
Sleep Disorders
o Insomnia
o persistent problems in falling or staying
asleep
o Narcolepsy
o uncontrollable sleep attacks
o cataplexy
o Sleep Apnea
o temporary cessation of breathing
o momentary re-awakenings
Sleep Disorders - children
• Night terrors— sudden arousal from
sleep and intense fear accompanied by
physiological reactions (e.g., rapid heart
rate, perspiration) that occur during slowwave sleep (first few hours of stage 4).
• Nightmares– a vivid dream depicting
frightening disturbing, anxiety-provoking
events. (early morning REM)
Sleepwalking and talking
Sleepwalking (somnambulism)
About 25% of all children have at least one
episode of sleepwalking. It typically occurs during
the first three hours of sleep (stage 4).
Sleepwalking and sleeptalking run in families.
Many people walk and talk in their sleep. It is
normal. They will usually return to bed, or they
may be guided there by a parent. It is not
dangerous to awaken a sleepwalker, as long as the
person feels safe and secure.
Sleep Paralysis
• Sleep Paralysis: when your brain wakes up from the
Rapid Eye Movement (REM), but your whole body is
paralyzed state
• horrible feeling where you awake but still stuck in a
state where you cant even move a muscle or talk
• some people report hearing and seeing things that are
not actually there
• Studies have found out that it is normal and causes no
damage on the human body.
• Sleep paralysis can happen before you go to sleep or
awakening up from REM sleep
Sleep Paralysis- Causes
• There is no exact cause on why some people
get this horrible sensation called sleep
paralysis.
• Causes could include: not getting enough
sleep, binge drinking, change in sleep pattern,
change in lifestyle (eating habits), passed
down from family
• Happens to 40% of the population!
Sleep Paralysis- Cures
• Stress plays a big role when your dealing with sleep paralysis so
make sure you take time to reflect things you need to change in
your life.
– Change your sleep patterns. Get your 8-9 hours a night sleep
– Your anxiety levels might be very high. Find out ways you can
stop
anxiety from taking over.
– Change your environment around you. Did you make a sudden
change in your life that’s not working out?
– More likely to experience when you sleep on your back.
– You might be depressed? Find ways to cope with depression
– Check your family history. Most of the time your parents might
have the same issue
– Work out at the gym or meditate
What do we Dream?
1. Negative Emotional Content: 8 out of 10
dreams have negative emotional content.
2. Failure Dreams: People commonly dream
about failure, being attacked, pursued,
rejected, or struck with misfortune.
3. Sexual Dreams: Contrary to our thinking,
sexual dreams are rare. Sexual dreams in men
are 1 in 10; and in women 1 in 30.
4. Dreams of Gender: Women dream of men
and women equally; men dream more about
men than women.
Why do we dream? – theories
1. To satisfy our own wishes: Sigmund Freud
suggested that dreams provide a psychic
safety valve to discharge unacceptable feelings.
The dream’s manifest (apparent) content may
also have symbolic meanings (latent content)
that signify our unacceptable feelings.
Critical Considerations: Lacks any scientific support;
dreams may be interpreted in many different ways.
Why do we dream? – theories
2. Information Processing: Dreams may help sift,
sort, and fix a day’s experiences in our
memories.
Critical Considerations: But why do we sometimes
dream about things we have not experienced?
Why do we dream?
3. Physiological Function: Dreams provide the
sleeping brain with periodic stimulation to
develop and preserve neural pathways.
Neural networks of newborns are quickly
developing; therefore, they need more sleep.
Critical Considerations: This may be true, but it does
not explain why we experience meaningful dreams.
Why do we dream?
4. Activation-Synthesis Theory: Suggests that the
brain engages in a lot of random neural
activity. Dreams make sense of this activity.
Critical Considerations: The individual’s brain is weaving
the stories, which still tells us something about the dreamer.
5. Cognitive Development: Some researchers
argue that we dream as a part of brain
maturation and cognitive development.
Critical Considerations: Does not address the
neuroscience of dreams.
Trivia Question!
How many days or years do you
think the average human spends
dreaming in a lifetime?
Random Facts about Dreams
-
Human beings spend roughly around 6 years of their
lifetime dreaming.
-
Blind people dream. Their dreams are auditory if they
were born blind. If they became blind at an early age,
they still dream of what they remember
-
Men get erections in their REM sleep and women have
an increased blood flow to their vaginas
-
If you avoid your sleep for more than 10 days, you will
die
-
A giraffe sleeps for only 2 hours a day
Common Dream Symbols
•
Falling is a common dream symbol that relates to our anxieties
about letting go, losing control, or somehow failing after a success.
•
Demons are sneaky evil entities which signify repressed emotions.
You may secretly feel the need to change your behaviors for the
better.
•
Houses can host many common dream symbols, but the building as
a whole represents your inner psyche. Each room or floor can
symbolize different emotions, memories and interpretations of
meaningful events.
•
Nudity is one of the most common dream symbols, revealing your
true self to others. You may feel vulnerable and exposed to others.
Common Dream Symbols
• Water comes in many forms, symbolizing the unconscious
mind. Calm pools of water reflect inner peace while a
choppy ocean can suggest unease.
• Vehicles may reflect how much control you feel you have
over your life - for instance is the car out of control, or is
someone else driving you?
• Mountains are obstacles, so to dream of successfully
climbing a mountain can reveal a true feeling of
achievement. Viewing a landscape from atop a mountain
can symbolize a life under review without conscious
prejudice.