STATES OF CONSCIOUSNESS

What is consciousness?

• A state of awareness….

– Includes the person’s feelings, sensations, ideas, and perceptions

STATES OF CONSCIOUSNESS

• Different levels of awareness that occur each day (I.e. sleeping, dreaming, thinking, etc)

• A person who is not completely aware is in a different level (state) of consciousness

• Consciousness can

be broken down into:– Waking consciousness: Includes all the

thoughts, feelings, and perceptions when we are awake and alert

– Altered States of Consciousness (ASC): A mental state that differs from waking consciousness

ASC:

• Examples of altered states of consciousness include:– Daydreaming– Sleep– Dreaming– Hypnosis– Meditation– intoxication

Sleep

• Was difficult to study until the development of the EEG (electroencephalograph), a device that records the electrical activity of the brain (brain waves)

• Other measures taken are muscular activity (using an EMG – electromyogram) and eyeball movement (using EOG – electro oculogram)

REM sleep was realized in 1953…With the invention of the EEG:

Why sleep?

• Recovery from exhaustion & stress?

• Primitive “hibernation”? (conserve energy)

• Stay out of trouble?• Clear minds of useless

information?

Hypothesis #1. Restoration and Recovery of Body Systems

• Organisms must replenish energy stores and repair itself after a period of energy use and wear & tear from the day

• There is little evidence that more repair occurs during sleep than just during awake rest

• The more physical the exertion, the more important non REM sleep is to recovery

• The more mental the exertion, the more NB REM sleep is (for memory and learning)

Hypothesis #2. Energy Conservation

• We sleep to conserve energy because metabolic rate is slower during sleep

Hypothesis #3: Memory Consolidation

• Sleeping reinforces learning and memory, while at the same time clearing out unneeded memories

• FYI lab rats live 2 – 3 yrs but deprived

of REM sleep, they survive an average

of 5 months – deprived of all sleep

live 3 weeks

Hypothesis #4: Protection from Predators

• Inactivity during sleep may minimize exposure to predators.

• At the same time however, one is usually unaware while sleeping – May be more vulnerable…..?

Hypothesis #5: Brain Development

• This proposed function of sleep is related to REM sleep, which occurs for long periods during fetal and infant development.

• REM sleep may be involved in the formation of new connections between neurons in the brain

Hypothesis #6: Discharge of Emotions

• Dreaming may provide a safe discharge of emotions

• Muscular paralysis prevents acting out dreams

• Activity in brain regions that control emotions, decision making, and social interactions is reduced during sleep relieves stress of it all?

Sleep is categorized into:

• NREM – Non-REM sleep (a.k.a. slow wave sleep)– This type has 4 stages

within it

– If deprived of this type of sleep, we feel physically tired

– This type is especially important after physical exertion

• REM sleep– Dreaming sleep

– Rapid-Eye-Movement

– Brain waves are very similar to waking life.

– About 20% of our sleep is REM

Stages of Sleep

• Stage 1 sleep begins with theta waves

• Stage 2 – theta waves with sleep spindles (rapid bursts of activity) and K-complexes

http://webspace.ship.edu/cgboer/genpsysleep.html

Sleep Spindles and K-Complexes

http://en.wikipedia.org/wiki/File:Stage2sleep_new.svg

• Stage 3 – delta waves• Stage 4 sleep (deepest

sleep) – more than 50% of brain waves are delta

• A person sleeping goes through one sleep cycle (all stages) about every 90 minutes

• The first sleep cycle of the night takes you into the deepest sleep

• Each subsequent cycle takes you less deep – most of your deep stage 4 sleep is early in the night

• REM is at the top of the cycle, in lighter sleep• REM accounts for about 20% of the sleep

time, and increases with each sleep cycle

Look again at the sleep cycle:

Hypnosis

• A form of altered consciousness

• People become highly suggestible to changes in behavior and thought

• People can be made conscious of things they normally are not aware of

Hypnosis continued…

• People can be made unaware of thing they normally are aware of

• Hypnosis does not put people “to sleep”

• People under hypnosis become highly receptive and responsive to certain internal and external stimuli

Everyday Hypnosis….

• Brain waves during each of these activities are very similar

• People can resist hypnosis by refusing to open their mind to the hypnotist.