Chapter 5 Variations in Consciousness

Waking and Sleeping Rhythms

When we are awake we are?In a state of Consciousness

Consciousness refers to the active processing of information in the brain.

It could be thought of as a form of short-term memory & attention combined.

It is the activity running through our heads or minds. (stream of consciousness)

Brain activity can be measured by using an EEG.

Central theory of conscious behavior can be found in:

Conscious

Subconscious

Unconscious

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FANTASIES

What are some common Daydreams & Fantasies?

Mr. Duez Fantasy

• They can help us prepare for future events.

• They can nourish our social development.

• Can substitute for impulsive behavior.

Why do we daydream?

Someone who imagines and recalls experiences with lifelike vividness and who spends considerable time fantasizing.

Fantasy Prone Personalities:

Biological Rhythms

Annual Cycles: seasonal variations (bears hibernation, seasonal affective disorder)

28 day cycles: menstrual cycle.

24 hour cycle: our circadian rhythm

90 minute cycle: sleep cycles.

Circadian Rhythm

• Our 24 hour biological clock.• Our body temperature & awareness

changes throughout the day.• It is best to take a test or study

during your circadian peaks.

How can the circadian rhythm help explain jet lag?

Circadian 24 hour biological processes that may be interrupted by exposure to light

Resets biological clock by affecting suprachiasmatic nucleus and pineal gland which secretes melatonin.

Jet lag & shift work can also knock circadian rhythms out of sync.

Sleep

Sleep Stages

There are 5 identified stages of sleep.

It takes about 90-100 minutes to pass through the 5 stages.The brain’s waves will change according to the sleep stage you

are in.The first 4 sages and know as NREM sleep.The 5 stage is called REM sleep.Rem lasts about 90 minutes (as night progresses we spend

more time in REM cycle). 4 to 6 cycles per night is typical.

Stage 1

• This is experienced as falling to sleep and is a transition stage between wake and sleep.

• It usually lasts between 1 and 5 minutes and occupies approximately 2-5 % of a normal night of sleep.

• eyes begin to roll slightly.• consists mostly of theta waves (high amplitude, low

frequency (slow)) • brief periods of alpha waves, similar to those present while

awake

Hallucinations can occur and feeling of falling.

Stage 2• This follows Stage 1 sleep and is the "baseline" of

sleep. • This stage is part of the 90 minute cycle and occupies

approximately 45-60% of sleep. • Brain waves slow down dramatically. Deeper stage

of sleep. Sleep spindles (bursts of neural activity or neural firings) occur.

• Not easy to wake up.

Stage 3 & 4• Stages three and four are

"Delta" sleep or "slow wave" sleep and may last 15-30 minutes.

• It is called "slow wave" sleep because brain activity slows down dramatically.

• From the "theta" rhythm of Stage 2 to a much slower rhythm called "delta" and the height or amplitude of the waves increases dramatically.

Stage 3 and 4 (cont.) • Contrary to popular belief, it

is delta sleep that is the "deepest" stage of sleep (not REM) and the most restorative.

• It is delta sleep that a sleep-deprived person's brain craves the first and foremost.

• In children, delta sleep can occupy up to 40% of all sleep time and this is what makes children unawake able or "dead asleep" during most of the night.

Stage 5: REM• REM: Rapid Eye Movement• This is a very active stage of sleep. • Composes 20-25 % of a normal

nights sleep. • Breathing, heart rate and brain

wave activity quicken. • Vivid Dreams can occur. • From REM, you go back to Stage 2• But the brain causes a decrease in

muscle tone and control. • Impossible to sleep walk in this

stage (the body is immobile).• REM cycles decline during

childhood and levels off at 20%

• 8 hours is the average need

• But we ALL sleep- about 25 years on average in our life.

How do you feel when you don’t get enough sleep?

Can you just make up lost sleep in 1 night?

NO

• We are not entirely sure why sleep occurs.

• There is a mechanism that causes us to fall asleep in the brain (2 really).

• And we believe it has an evolutionary purpose as well.

• Yet the body does not do as much recuperation during sleep as we might believe,

• & the brain is active during sleep, so we are not really decreasing activity.

Sleep Disorders

InsomniaRecurring problems in falling

or staying asleep.• Not your once in a while (I have a big

test tomorrow) having trouble getting to sleep episodes.

• Insomnia is not defined by the number of hours you sleep every night.

Narcolepsy• Characterized by

uncontrollable sleep attacks.

• Lapses directly into REM sleep (usually during times of stress or joy).

• Excessive sleepiness. Unpredictable and uncontrolled.

Sleep ApneaA sleep disorder characterized by

temporary cessations of breathing during sleep and consequent momentary reawakenings.

Night Terrors• A sleep disorder characterized

by high arousal and an appearance of being terrified.

• Occur in Stage 4, not REM, and are not often remembered.

Sleepwalking(Somnambulism)

• Sleepwalking is a sleep disorder effecting an estimated 10% of all humans at least once in their lives.

• Sleep walking most often occurs during deep non-REM sleep (stage 3 or stage 4 sleep) early in the night.

Symptoms and Features:• Ambulation (walking or moving

about) that occurs during sleep. The onset typically occurs in pre-pubertal children.

• difficulty in arousing the patient during an episode

• amnesia following an episode • episodes typically occur in the first

third of the sleep episode • polysomnographic monitoring

demonstrates the onset of an episode during stage 3 or 4 sleep

• Fatigue (which is not the same as drowsiness)

• Stress and anxiety 

DreamsA sequence of images, emotions, and

thoughts passing through a sleeping person’s mind.

Manifest Content: the remembered storyline of a dream.

Latent Content: the underlying meaning of a dream.

Manifest Content

Latent Content

Why do we Dream?

Content of one's dreams may be affected by one's gender

events in one's life, & external stimuli experienced during the dream.

There are variations across cultures in dream recall, content, and interpretation.

Freud’s wish-fulfillment Theory

• Dreams are the key to understanding our inner conflicts.

• Ideas and thoughts that are hidden in our unconscious.

• Manifest and latent content

• Freud argued that the purpose of dreams was wish fulfillment.

Information-Processing Theory

• Dreams act to sort out and understand the memories that you experience that day.

• REM sleep does increase after stressful events.

Problem Solving

Cartwright has articulated a problem-solving view

Activation Synthesis TheoriesDuring the night our

brainstem releases random neural activity, dreams may be a way to make sense of that activity.

• Hobson & McCarley assert that dreams are side effects of the neural activation seen during REM sleep.

hypothesis – When we dream, our brain is

as active as while we are awake: we experience images, sensations, etc. that we synthesize into a dream.

REM Rebound• The tendency for

REM sleep to increase following REM sleep deprivation.

• What will happen if you don’t get a good nights sleep for a week, and then sleep for 10 hours?

You will dream a lot.