Module_7vs9_Final

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Sleep and Dreams

CONTINUUM OF CONCIOUSNESS

Different states

 Consciousness

 refers to different levels of awareness of one’s thoughts and feelings

 Continuum of consciousness

 refers to a wide range of experiences, from being acutely aware and alert to being totally unaware and unresponsive

CONTINUUM OF CONCIOUSNESS

(CONT’D)

Different states

Controlled processes

 require full awareness, alertness, and concentration to reach some goal; usually interfere with execution of other ongoing activities

Automatic processes

 require little awareness, take minimal attention, and don’t interfere with other ongoing activities

Daydreaming

 requires low level of awareness, often occurs during automatic processes, and involves fantasizing or dreaming while awake

CONTINUUM OF CONCIOUSNESS

(CONT’D)

Different states

 Altered states

 Result from using any number of procedures, such as meditation, psychoactive drugs, hypnosis, or sleep deprivation, to produce an awareness that differs from normal consciousness

 meditation is an altered state

CONTINUUM OF CONCIOUSNESS

(CONT’D)

Sleep and dreams

 Sleep

 consists of five stages that involve different levels of awareness, consciousness, and responsiveness as well as different levels of physiological arousal deepest state of sleep borders on unconsciousness

 Dreaming

 unique state of consciousness in which we’re asleep but experience a variety of astonishing visual, auditory, and tactile images

CONTINUUM OF CONCIOUSNESS

(CONT’D)

Unconscious and implicit memory

Freud’s theory, when we’re faced with very threatening wishes or desires, especially if they’re sexual or aggressive

Defend self-esteem by placing these thoughts in the unconscious

 Can’t voluntarily recall unconscious thoughts

Implicit or nondeclarative memory

 Learning without awareness

 Occurs in emotional situations or in acquiring habits

CONTINUUM OF CONCIOUSNESS

(CONT’D)

Unconscious

 Can result from disease, trauma, a blow to the head, or general medical anesthesia

 Results in total lack of sensory awareness and complete loss of responsiveness to one’s environment

RHYTHMS OF SLEEPING & WAKING

Biological clocks

 Biological clocks are internal timing devices that are genetically set to regulate various physiological responses for different periods of time

Circadian rhythm

 Refers to a biological clock that’s genetically programmed to regulate physiological responses within a time period of 24 hours

RHYTHMS OF SLEEPING & WAKING

(CONT’D)

Location of biological clocks

 Suprachiasmatic nucleus

 part of hypothalamus lies in the lower middle of the brain regulates a number of circadian rhythms regulates sleep-wake cycle highly responsive to change in light

RHYTHMS OF SLEEPING & WAKING

(CONT’D)

RHYTHMS OF SLEEPING &

WAKING (CONT’D)

 Interval timing clock

 can be started and stopped like a stopwatch gauges the passage of seconds, minutes, or hours helps creatures time their movements, such as knowing when to start or stop doing some activity located in the basal ganglia 

 Food-entrainable circadian clock

“midnight snack” clock regulates eating patterns in people and animals obese people might have an abnormality in their clock

(located in hypothalamus)

RHYTHMS OF SLEEPING &

WAKING (CONT’D)

Circadian problems and treatments

 Shift workers

 can result in decreased performance in cognitive and motor skills sleep-wake clocks have prepared bodies for sleep (means workers feel sleepy, are less attentive and alert, and are often in a lousy mood)

 Jet lag

 experience of fatigue, lack of concentration, and reduced cognitive skills occurs when travelers’ biological circadian clocks are out of step or synchrony with the external clock times at their new location

RHYTHMS OF SLEEPING &

WAKING (CONT’D)

Circadian problems and treatments

 Resetting clock

 light therapy: use of bright artificial light to reset circadian clocks and combat the insomnia and drowsiness that plague shift workers and jet lag sufferers helps people with sleeping disorders in which the body fails to stay in time with the external environment

RHYTHMS OF SLEEPING &

WAKING (CONT’D)

Circadian problems and treatments

 Melatonin

 hormone secreted by the pineal gland (oval-shaped group of cells in the center of the brain) melatonin secretion increases with darkness and decreases with light suprachiasmatic nucleus; regulates the secetion of melatonin plays role in the regulation of circadian rhythms and in promoting sleep

WORLD OF SLEEP

Stages of sleep

 Distinctive changes in the electrical activity of the brain and accompanying physiological responses of the body that occur as you pass through different phases of sleep

Alpha stage

 Feeling of being relaxed and drowsy, usually with the eyes closed

WORLD OF SLEEP (CONT’D)

Non-REM sleep

 Where you spend approximately 80% of your sleep time

 Divided into four stages, identified by particular pattern of brain waves and physiological responses

 Begin with stage 1 and gradually enter stages 2, 3, and 4

WORLD OF SLEEP (CONT’D)

Non-REM sleep

 Stage 1 sleep

 transition from wakefulness to sleep that lasts one to seven minutes gradually lose responsiveness to stimuli and experience drifting thoughts and images presence of theta waves

WORLD OF SLEEP (CONT’D)

Non-REM sleep

 Stage 2 sleep

 beginning of what we know as sleep high-frequency bursts of brain activity called sleep spindles muscle tension, body temperature, and heart rate gradually decrease

 more difficult to be awakened

WORLD OF SLEEP (CONT’D)

Non-REM sleep

 Stages 3 and 4

 also called slow wave or delta sleep waves of very high amplitude and very low frequency (delta waves) stage 4 is often considered the deepest stage of sleep; most difficult to be awakened from

 heart rate, respiration, temperature, and blood flow to the brain are reduced marked secretion of growth hormone (GH), which controls levels of metabolism, physical growth, and brain development

WORLD OF SLEEP (CONT’D)

REM sleep

 Makes up the remaining 20% of your sleep time

 Stands for “rapid eye movement”

 Eyes move rapidly back and forth behind closed lids

 Pass into REM sleep about five or six times throughout the night with about 30 to 90 minutes between periods

 REM sleep remains for about 15 to 45 minutes then passes into non-REM sleep

WORLD OF SLEEP (CONT’D)

REM sleep

 REM behavior disorder

 usually occurs in older people voluntary muscles aren’t paralyzed sleepers can and do act out their dreams such as fighting off attackers in dreams

 REM rebound

 refers to individuals spending an increased percentage of time in REM sleep if they were deprived of REM sleep on the previous nights

WORLD OF SLEEP (CONT’D)

QUESTIONS ABOUT SLEEP

According to a national survey

 16% of adults sleep less than six hours

 24% sleep 6 to 6.9 hours

 31% sleep 7 to 7.9 hours

 26% sleep 8 or more hours

 Average: 6.9 hours a night

WORLD OF SLEEP (CONT’D)

QUESTIONS ABOUT SLEEP

Why do I sleep?

 Repair theory

 activities during the day deplete key factors in brain/body that sleep replenishes or repairs primarily a restorative process

 Adaptive theory

 sleep evolved because it prevented early humans and animals from wasting energy and exposing themselves to the dangers of nocturnal predators

QUESTIONS ABOUT SLEEP

What causes sleep?

 Master sleep switch

VPN (ventrolateral preoptic nucleus); group of cells in the hypothalamus switched on VNP secretes a neurotransmitter (GABA) that turns off areas that keep the brain awake

 switched off VNP activates certain brain areas

 Reticular formation

 column of cells that stretches the length of the brain stem arouses and alerts the forebrain and prepares it to receive information from all the senses

CULTURAL DIVERSITY

Seasonal affective disorder, or SAD

 Pattern of depressive symptoms, such as loss of interest or pleasure in nearly all activities; cycles with the seasons

 Includes

 lethargy excessive sleepiness overeating weight gain craving carbohydrates

SAD has become a subtype (Seasonal Pattern Specifier) of major depression (APA 2000)

WORLD OF DREAMS

Theories of dream interpretation

 Freud’s theory of dream interpretation

 we have a “censor” that protects us from realizing threatening and unconscious desires or wishes, especially those involving sex or aggression

“censor” protects us from threatening thoughts by transforming our secret, guilt-ridden, and anxiety-provoking desires into harmless symbols that appear in our dreams and don’t disturb our sleep or conscious thoughts

WORLD OF DREAMS (CONT’D)

 Extensions of waking life theory

 dreams reflect the same thoughts, fears, concerns, problems, and emotions that we have when awake

 Activation-synthesis theory

 dreaming occurs because brain areas that provide reasoned cognitive control during the waking state are shut down sleeping brain is stimulated by different chemical and neural influences that result in hallucinations, delusions, high emotions, and bizarre thought patterns that we call dreams

WORLD OF SLEEP (CONT’D)

WORLD OF DREAMS (CONT’D)

Theories of dream interpretation

 Threat simulation theory

 dreaming serves a biological function by repeatedly simulating events that are threatening in our waking lives so our brain can practice how it perceives threats and rehearse our responses to such events

WORLD OF DREAMS (CONT’D)

Typical dreams

 What do people dream about?

 several characters involve motion take place indoors more often than out visual sensation, but rarely sensations of taste, smell, or pain seem bizarre, may include flying or falling without injury may be recurrent (dreams of being threatened, pursued, or trying to hide)

WORLD OF DREAMS (CONT’D)

Typical dreams

 Involve emotions of anxiety or fear rather than joy or happiness

 Rarely involve sexual encounters and are almost never about sexual intercourse

 Rarely can we control or dream about something we intend to dream about

 Dreams usually have visual imagery and are in color in sighted people

 Blind people from birth dream in tactile, olfactory, or gustatory (taste), not visual

APPLICATION: SLEEP PROBLEMS

& TREATMENTS

Insomnia

 Difficulties in either going to sleep or staying asleep through the night

 Associated with daytime complaints

 fatigue impairment of concentration memory difficulty lack of well-being

APPLICATION: SLEEP PROBLEMS

& TREATMENTS (CONT’D)

Nondrug treatment

 Go to bed only when sleepy

 Put light out immediately; don’t read or watch TV

 If not asleep in 20 minutes, get out of bed and relax in another room until tired again

 Repeat last step as often as required

 Set alarm for same time each morning

 Don’t nap during the day

 Follow program rigidly for several weeks

APPLICATION: SLEEP PROBLEMS

& TREATMENTS (CONT’D)

Drug treatment

Benzodiazepines (Dalmane, Xanax, Restoril)

 reduce anxiety, worry, and stress effective in moderate dosages in short term (2 to 4 weeks) treatment; prolonged use in higher dosages may lead to dependence

Nonbenzodiazepines (Ambien, Sonata, Lunesta)

 rapidly becoming popular fast acting reduce daytime drowsiness; fewer cognitive side effects less likely to lead to dependence

APPLICATION: SLEEP PROBLEMS

& TREATMENTS (CONT’D)

Sleep apnea

Repeated periods during sleep when a person stops breathing for 10 seconds or longer; may repeatedly stop breathing, momentarily awaken, and then resume sleep

Results in insomnia; exhaustion during the day

Narcolepsy

Chronic disorder marked by excessive sleepiness

Form of sleep attacks or short periods of sleep throughout the day

Accompanied by brief periods of REM sleep and loss of muscle control (cataplexy)

Triggered by emotional change

APPLICATION: SLEEP PROBLEMS

& TREATMENTS (CONT’D)

Night terrors

Occur in stage 3 or 4 (delta sleep)

Frightening experiences that often start with a piercing scream, followed by sudden awakening in a fearful state with rapid breathing and increased heart rate

Usually no memory of experience in the morning

Nightmares

Occur during REM sleep

Very frightening and anxiety-producing images occur involving great danger

Upon awakening, person can describe nightmare in great detail

APPLICATION: SLEEP PROBLEMS

& TREATMENTS (CONT’D)

Sleepwalking

 Occurs in stage 3 or 4 (delta sleep)

 Sleeper gets up and walks while literally sound asleep

 Has poor coordination

 Clumsy but can avoid objects

 Can engage in limited conversation

 No memory of sleepwalking

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