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

Sleep Spindles and K-Complexes

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.