Ch. 4: States of Consciousness

Consciousness

Waking ConsciousnessThoughts, feelings, and perceptions that occur

when we are awake and alert

Altered States of ConsciousnessA mental state that differs noticeably from

normal waking consciousness, including sleep, dreaming, meditation, or drug-induced states

Explaining Waking Consciousness

Stream of information resulting from the activity of the thalamus--which analyzes and interprets informationConsciousness may only be the “tip of the iceberg” that includes unconscious mental activitiesConsciousness is also viewed as an adaptation allowing us to get along with others in our group (humans)

Daydreaming and Fantasy

Spontaneous shifts if attention away from the here and now into a make-believe world

Urge to daydream peaks about every 90 min.

Daydreams may provide stress relief and encourage creativity

Circadian Cycles: The Biological Clock

Circadian cycles are those that last “about a day”Circadian rhythms are governed by an area of the hypothalamus called the suprachiasmatic nucleus (SCN)Controls body temperature, metabolism, blood pressure, hormone levels and hungerJet lag is the result of desynchronization of the circadian rhythm

The Rhythms of Sleep

Brain waves and sleep stages Stage 1 Stage 2 Stage 3 Stage 4 REM sleep

REM Sleep

“Rapid Eye Movement”REM called paradoxical sleepBrain waves similar to waking state, but

person is deeply asleep and unable to move

Most dreaming takes place during REM

Sleep Patterns Across the Life Span

Changes In REM and NREM

Sleep Disorders

Sleeptalking and Sleepwalking Usually occurs during Stage 4 sleep More common in children Sleepwalking more common in boys

Night terrors Episodes of fright that occur during stages 3 or 4 of

NREM sleep Person may sit up or scream, but likely will not recall

the episode in the morning

InsomniaDifficulty falling asleep or remaining asleepAffects ~ 35 million AmericansMay be related to stress, depression, medicationCan also be caused by noise, temperature, or

trying to sleep in a new environment

Sleep Disorders

ApneaPerson stops breathing momentarily during

sleepAffects ~ 10-12 million Americans

Sleep Disorders

Narcolepsy Suddenly falling asleep without

warning during waking hours Narcoleptics often experience loss of

muscle tone as well May also drop into REM sleep

immediately, causing hallucinations Likely caused by a central nervous

system defect

Sleep Disorders

Why Do We Dream?

Dreams as unconscious wishesFreud thought dreams were the “royal road to

the unconscious”Manifest content

What the dreamer remembers about the dreamLatent content

The hidden, unconscious meaning of the dream

Dreams and information processing Information gathered during the day is reprocessed

to strengthen memoryDreams and neural activity Activation-synthesis hypothesis Random outbursts of nerve-cell activity are

interpreted as stories by higher brain centersDreams and waking life Extension of concerns in daily life

Why Do We Dream?

The older we get, the more likely it is that we will suffer from some kind of sleep disorder.

> 50 % of people over 64 years old suffer from some type of sleep disorder.

While the hormonal and physical changes that occur as we age will likely affect sleep, especially in menopausal women, the increased presence of other medical conditions and disorders is also a factor that tends to upset the sleep of the elderly.

Sleep & Aging

SLEEP DEPRIVATION

Menachem Begin, Former Israeli prime minister (1977-83)

Mr. Begin described his sleep deprivation experience, while being held captive by the Russian KGB:

"In the head of the interrogated prisoner, a haze begins to form. His spirit is wearied to death, his legs are unsteady, and he has one sole desire: to sleep... Anyone who has experienced this desire knows that not even hunger and thirst are comparable with it."

Without adequate rest, the brain's ability to function quickly deteriorates.

Concentration levels drop Memory impaired Problem solving greatly impaired Decision-making abilities compromised Brain falls into rigid thought patterns Hallucinations Depression Heart disease Hypertension Irritability Slower reaction times Slurred speech Tremors

SLEEP DEPRIVATION: Effects

Causes of sleep deprivation can be divided into four broad areas:

•lifestyle

•health complications

•medication side effects

•clinical disorders

Caffeine &/or alcohol before bedtime is among the most common causes of sleep deprivation.

SLEEP DEPRIVATION: Causes

SLEEP DEPRIVATION: Causes

Weight Changes

Dramatic weight changes, especially weight gain, are also common effects of sleep deprivation

Because the amount and quality of the sleep we get affects our hormone levels, namely our levels of leptin and ghrelin

Sleep & Aging

The older we get, the more likely it is that we will suffer from some kind of sleep disorder.

Over 50 percent of people over 64 years old suffer from some type of sleep disorder.

Hormonal and physical changes that occur as we age will likely affect sleep, especially in menopausal women.

SLEEP DEPRIVATION: Effects

Menopause is the time in a woman's life when the function of the ovaries ceases

The ovaries are the main source of female hormones

The average age of menopause onset is 51 years old.

Symptoms, including fatigue, memory problems, irritability, and rapid changes in mood

Hot flashes & night sweats

MENOPAUSE

SLEEP DEPRIVATION & Sports Performance

Some recent studies have found that that sleep deprivation can slow glucose metabolism by as much as 30 to 40%.

Eve Van Cauter, Ph.D., from the University of Chicago Medical School, studied the effects of three different durations of sleep in 11 men ages 18 to 27.

SLEEP DEPRIVATION & Sports Performance

For the first three nights of the study, the men slept eight hours per night;

For the next six nights, they slept four hours per night;

For the last seven nights, they slept 12 hours per night.

SLEEP DEPRIVATION & Sports Performance

Results showed that after four hours of sleep per night (the sleep deprivation period), they metabolized glucose least efficiently.

Levels of cortisol (a stress hormone) were also higher during sleep deprivation periods, which has been linked to memory impairment, age-related insulin resistance, and impaired recovery in athletes.

Meditation and Hypnosis

Meditation Techniques which improve the ability to

focus and relaxSuppresses activity of the sympathetic

nervous system

HypnosisTrancelike state in which people can respond

more easily to suggestionHypnosis has been used in conjunction with

psychotherapy and as an anesthetic in dentistry and surgery

Meditation and Hypnosis