Download Chapter 3

Body Rhythms and Mental
States
Chapter 3
What is the Nature of
Consciousness?
Consciousness –
The brain’s awareness of internal and
external stimulation
(*filter or interpretation of events NOT a
direct copy)
The Functions and Structures of
Consciousness
• Restricts attention
• Combines sensation with learning
and memory
• Helps us select personally
meaningful stimuli
• Allows us to draw on lessons stored
in memory
Mental Control
• Attention
(limited resource)
*White Bear Study
• Automatic vs. Contolled
Processes
• Preattentive Processes
Sleep and Dreaming
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Circadian rhythms
Rapid eye movements (REM)
Sleep paralysis, ‘paradoxical sleep’
REM rebound
Non-REM (NREM) sleep
Sleep Cycle
• NREM = 4 stages
*deepest sleep early in
night
• REM replaces Stage 1
• 60-90 between REM
(most people have 4-6
cycles per night)
Realms of Sleep
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Stage 1. Feel self drifting
on the edge of
consciousness.
Stage 2. Minor noises
won’t disturb you.
Stage 3. Breathing and
pulse have slowed down.
Stage 4. Deep sleep.
REM. Increased eye
movement, loss of
muscle tone and
dreaming.
The Sleep Cycle
The Need for Sleep
Over the years, the need for REM sleep
decreases considerably, while the need for
NREM sleep diminishes less sharply
Why We Sleep
• The exact function of sleep is uncertain
but the possible functions include:
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eliminate waste products from muscles
repair cells
strengthen the immune system
recover abilities lost during the day
conserve energy
Aid in learning/memory
Why We Dream:
A Cross-Cultural Perspective
• Folk theories (visions, religion)
• Scientific approach
– Dreams as meaningful events
– Dreams as random brain activity
Dreams as Meaningful Events
• To guard sleep (disguising images)
• To serve as sources of wish
fulfillment
• Differences in dream content by
age, gender, and culture
Dreams as Random
Brain Activity
Hypnosis
Hypnosis –
Induced state of altered awareness,
characterized by heightened
suggestibility and deep relaxation
Hypnotizability –
Degree to which an individual is
responsive to hypnotic suggestions
Altered Consciousness
Psychoactive drugs –
Chemicals that affect
mental processes and
behavior by their effects
on the nervous system
Depressants
Opiates
Stimulants
Hallucinogens
The Psychology of Drug Effects.
• Reactions to psychoactive drugs depend on:
– Physical factors such as body weight,
metabolism, initial state of emotional arousal and
physical tolerance.
– Experience or the number of times a person has
used a drug.
– Environmental factors such as where and with
whom one is drinking.
– Mental set or expectations for drug’s effects.
Process of Addiction
Psychological
• Dependence
• Associations
• People, Places, &
Things
Biological/Physical
• Tolerance/dependence
• Withdrawal