Sleep and Dreams
Consciousness – state
of awareness
Altered state of
consciousness – not
completely aware
• Sleep
Stages of Sleep
Stage I –
• Lightest level of sleep
• Lasts up to 10 minutes
• Alpha waves (awake)
replaced by Theta
waves
Stage II –
• Eyes roll slowly from
side to side
• Lasts about 30
minutes
Stages of Sleep
Stage III –
• Large amplitude delta
waves sweep brain
every second or so
Stage IV – REM – rapid eye
movement
• Deepest sleep
• Delta waves most of REM Sleep – rapid
the time eye movements,
• Enter REM (active) high level of brain
sleep activity, deep
relaxation, dreaming
How Much Sleep is Enough?
Newborns – 16 hours a day
16 Yr-Olds – 10-11 hours a day
Students in Grad School – 8 hours a day
Older Adults - As little as 5 hours a day
Circadian Rhythm – biological
clock – regulates
physiological functions on a
24 hour cycle
The Need for Sleep
Sleep Disorders
Insomnia –
• Failure to get enough
sleep to feel rested
Sleep Apnea –
• Trouble breathing
while sleeping
– snoring, blockage deprives
sleeper of oxygen
Sleep Disorders
Narcolepsy –
• Suddenly falling
asleep or feeling very
sleepy during the
day
Nightmares/Night Terrors
• Unpleasant dreams
• Screaming, panic, or
confusion in Level IV
sleep
Sleep Disorders
Sleepwalking –
• walking or carrying
out behaviors while
asleep
Sleeptalking
• Talking (carrying on
a conversation) while
asleep
Dreams
• Mental activity that
occurs during sleep
• Most are in
commonplace
settings
• Emotions are usually
negative In dreams
• Take place in real
time
Dream Interpretation
• Freud – clues or
thoughts the dreamer
refuses to acknowledge
while awake
• Inuit – entrance to the
spiritual world of the
dead
• Modern scientists:
• stimulation of certain brain
cells in sleep
• problem-solving
mechanism
• way of removing unneeded
memories
Power of Sleeping Brain
Hypnosis
• Form of altered
consciousness in which
people become highly
suggestible to changes in
behavior and thought
•Focus attention on one
tiny aspect of reality and
ignore other inputs
•It is not sleep
•Involves mutual trust to
succeed
Uses for Hypnosis
• Posthypnotic
Suggestion - Suggestion
made during hypnosis
that influences a
person’s behavior later
•Hypnotic Analgesia – to
reduce perception of pain
•Reveal problems
•Gain insight into your
life
Biofeedback
• Using machines to
control physiological
processes
–Heart rate
–Brain activity (EEG)
–Blood pressure
–Skin temperature
–Sweat-gland activity
Meditation
• Focusing attention to
clear the mind and
produce relaxation
–Transcendental
meditation – repetition of
a mantra (Sanskrit phrase)
–Mindfulness meditation –
focus on the present
moment (Buddhist)
–Breath Meditation –
concentrate on breathing
Drugs and Consciousness
• Psychoactive Drugs
–Interact with the
nervous system to alter
a person’s mood,
perception, and
behavior
–Act as a
neurotransmitter by
telling a nerve cell
whether or how to fire 2005
Types of Drugs
• Marijuana
–Made from dried leaves
of Indian hemp (cannabis
sativa)
–Not physically addictive,
but psychologically
addictive
–Can amplify feelings
(good or bad) and disrupts
memory functions
–More damaging than
cigarettes on lungs
Types of Drugs
• Hallucinogens
–Main effect is to produce
hallucinations
(perceptions that have no
direct external cause)
–LSD is most potent –
“trip” can last 6-12 hours
Types of Drugs
• Opiates
–Produce pain reduction,
euphoria (pleasurable
state between wake and
sleep), and constipation
–Can lead to physical
addiction or even death
(overdose)
–Examples: opium,
morphine, heroin
Types of Drugs
• Alcohol
–Loosens inhibitions
–Seemingly a stimulant,
but really a depressant
–Permanent brain or liver
damage can result from
prolonged heavy use
Abuse/Treatment
• Abusers are:
–Those who regularly use
illegal drugs
–Those who excessively
use legal drugs
• Treatment:
–Must admit the problem
–Enter treatment program
or get therapy
–Remain drug free
War on Drugs Project
• In groups of 3-4 pick a card with a drug
listed
•Make a poster in the “War on Drugs” to show
the drug’s effects and a slogan to encourage
teens not to use the drug
•Present the poster and your “pitch” to the
class
Sensation
• In the next few
seconds, something
peculiar will start hap
pening to the material
youa rereading. Iti
soft ennoter alized
howcom plext
heproces sof rea ding
is.
• Sensation – what
occurs when a
stimulus activates a
receptor (sense organ)
Sensation
• Perception –
organization of
sensory information
into meaningful
experiences
• Psychophysics –
study of relationship
between sensory
experiences and the
physical stimuli that
cause them
Sensation
• Absolute Threshold –
weakest amount of stimulus
required to produce a
sensation
– Vision – seeing a candle flame
30 miles away on a clear night
– Hearing – hearing a watch tick
20 feet away
– Taste – tasting a teaspoon of
sugar dissolved in 2 gallons of
water
– Smell – smelling one drop of
perfume in a 3 room house
– Touch - feeling a bee’s wing
falling a distance of 1
centimeter onto your cheek
Sensation
• Difference Threshold –
smallest change in
physical stimulus that can
be detected between two
stimuli
• Weber’s Law – the larger
or stronger a stimulus,
the larger change
required for a person to
notice that anything has
happened to it
Sensation
• Signal Detection
Theory – study of
people’s tendency
to recognize a
stimulus against a
background of
competing stimuli
Sensation
• Stroop Effect –
automatic
processing acts
as an interference
Try to name the colors of the words as
fast as you can
The Senses
• Vision –
– Pupil – where light
enters the eye
– Lens – focuses light
– Retina – coating on
back of eye and
contains light-
sensitive receptor
cells
– Optic nerve – carries
impulses from retina
A person with color deficiency
to brain cannot see the number
The Senses
• Hearing –
– Sound waves pass
into the inner ear
– Tiny, hairlike cells
change sound
vibrations into
neuronal signals
which travel
through the
auditory nerve to
the brain
The Senses
• Balance –
– Maintained by the
vestibular system
– three
semicircular
canals located in
inner ear and
connected to the
brain by a nerve
The Senses
• Smell & Taste –
– Messages about
smells enter brain
through the
olfactory nerve
– Taste (sour, salty,
bitter, sweet)
perceived by
receptors in taste
buds on the
tongue
The Senses
• Skin senses –
– Receptors in skin
perceive pressure,
warmth, cold, and
pain
– Pain sensations –-
- sharp, localized
pain
- dull, generalized
pain
The Senses
• Body senses –
– Kinesthesis –
sense of
movement and
body position
– Works with
vestibular and
visual senses to
maintain balance
and posture
Perception
• Principles of Perceptual
Organization –
– Gestalt – organizing bits
and pieces of
information into
meaningful wholes
• We fill the gaps in music,
voices, sounds, objects
Perception
• Principles of Perceptual
Organization –
– Figure-Ground
Perception – ability to
discriminate between a
figure and its
background
• Visual – shapes
• Hearing – music, voices, a
particular noise
Perception
• Principles of Perceptual
Organization –
– Perceptual Inference –
we assume perceptions
that are not based on
sensory information
• Dog barking
• Road continues over a hill
Perception
• Subliminal Perception –
– Brief auditory or visual
messages presented
below the absolute
threshold
• Used in marketing
• “drink Coke”, “eat
popcorn”
Perception
• Shape Constancy –
– Tendency to perceive
certain objects in the
same way regardless of
changing angle, distance
or lighting
Perception
• Illusions –
– Incorrect perceptions
Perception
Perception
• Extra Sensory
Perception (ESP) –
– Ability to gain
information by some
means other than
ordinary senses