chapter 6: consciousness. chapter outline 1. when we are awake: conscious awareness 2. preconscious...

Chapter 6: Consciousness

Chapter Outline

1. When we are awake: Conscious awareness

2. Preconscious and unconscious states3. When we are asleep4. Hypnosis 5. Meditation6. Psychoactive drugs

© John Wiley & Sons Canada, Ltd.

When We Are Awake: Conscious Awareness

What is consciousness? Everything you are thinking about right now! Your awareness of your surroundings and yourself

Stream of consciousness—a continuing flow of

changing thoughts (William James, 1890)Consciousness involves

Attention Monitoring Remembering Planning


Conscious Awareness and the Brain

Different areas of the brain are responsible for attention and for one’s awareness of that attention Cerebral cortex Thalamus

Intralaminar nuclei and midline nuclei


Conscious Awareness and the Brain

Inattentional blindness—failure to notice things around us to which we are not paying attention

Blindsight—being unaware of what has reached our attention

Conscious awareness—being aware of what has reached our attention

Conscious awareness of self develops around 18 months


Preconscious and Unconscious States

• Preconscious—information from your past that is stored in your long-term memory and can be easily accessed • Example: What you did last weekend

• Unconscious—information from your past that is stored in your long-term memory but cannot be easily accessed• Freud: a repressed memory of a significant

traumatic event


Cognitive View of the Unconscious

We have two types of memory: Explicit—memories that we are consciously aware of

Examples include memories of things we have done and facts

Implicit—memories that we are unconsciously aware of Examples include knowing how to ride a bike; it is

difficult to consciously explain how to balance on a bike


When We Are Asleep

Why do we sleep? Adaptive theory of sleep—humans can

conserve energy while it is dark and they can’t hunt for food. Also, keeps humans away from predators that are more active at night

Restoration theory—holds that sleep restores our brains and bodies


Sleep Needs of Various Animals


Circadian Rhythm

Circadian rhythm is a 24-hour sleep/wake cycle Controlled by the

suprachiasmatic nucleus (SCN)

What causes our circadian rhythm? Genetic differences

Morning people vs. evening people

Some people need more sleep than others

Environmental differences Low sunlight triggers

production of melatonin, which helps to induce sleep


Sleep Cycle

90–100 minute sleep cycle One cycle goes through Stage

1, 2, 3, 4, and REM sleep We have about five cycles a

night


Stages of Sleep

Stage 1—a transition into sleep (5 min) At sleep, alpha waves change to theta waves HR slows, BP decreases

Stage 2—harder to wake (15-20 min) More relaxed Sleep spindles (burst of rapid brain waves)

Stage 3—deeper sleep (5-15 min) Theta waves and delta waves

Stage 4—deepest sleep (20-30 min) Slow HR, brain and body in total relaxation (20-30 min) Deepest sleep Mostly delta waves Sleep walking and bed wetting are more likely


REM Sleep

Rapid eye movement sleep (REM) stage of sleep is associated with rapid and jagged brain wave patterns, increased heart rate, rapid and irregular breathing, rapid eye movements, and dreaming Paradoxical sleep

Non-REM sleep (NREM)—Stages 1 through 4 of normal sleep pattern

Hypnagogic state—vivid sensory phenomena during presleep Myoclonic jerk—sharp muscular spasm


Why Do We Dream?

Freudian theory of dreams Wish fulfillment and conflict resolution

Manifest and latent contentInformation processing theory

Dreams involve processing information from the day (i.e., encoding memory and problem solving)

Dreams could be a mental realm where we can solve problems and think creatively

Activation-synthesis theory During sleep the brain has a lot of random activity Dreams are an attempt to make sense of this Dreams reflect the brains efforts to make sense out of or

find meaning in the neural activity that takes place during sleep


Activation-Synthesis Model


Sleep and Age


Sleep Deprivation

If we could sleep as long as we wanted, most people would sleep 9–10 hours

Chronic sleep loss results in General depressed state Lower immune system Lower ability to concentrate Higher incidence of accidents Lower productivity and higher likelihood of making mistakes

Circadian rhythm sleep disorder–excessive sleepiness or insomnia as a result of a mismatch between their own sleep-wake pattern and the sleep-wake schedule of most other people in their environment


Common Sleep Disorders

Insomnia Most common Difficulty going to sleep, staying asleep, or wake

early Caused by stress, drug dependence, pain,

depressionSleep apnea

Second most common Repeatedly stops breathing during night Possible to have hundreds of attacks per night Can lead to cardiac arrest


Sleep Disorders

Narcolepsy Excessive daytime

sleepiness Suddenly fall into REM

sleep during the day Can last up to 15 minutes Genetic factors involved No cure

Sleepwalking Most common in children Occurs in Stages 3 or 4 Appears to be inherited


Sleep Disorders

Night terrors Stages 3 or 4 Child screams in panic; goes back to sleep

immediately and does not remember the event in the morning

Resolves by adolescenceNightmare disorder

Experience frequent nightmares Nightmares are more common when stressed

and in children


Hypnosis

Hypnosis—altered state of consciousness with heightened suggestibility, deep relaxation, and intense focus

Posthypnotic responses Posthypnotic amnesia Hypnotic hallucinations Decreased activity in

anterior cingulate cortex when used to reduce pain


How Hypnosis Works


Meditation

Meditation—group of technique designed to turn one’s consciousness away from the outer world toward one’s inner cues and awareness Benefits include: relaxing and pleasant

feelings; treating pain, asthma, high blood pressure, heart problems, skin disorders, diabetes, and viral infections


Types of Meditation

Yoga—different poses Regulates blood flow, heart rate, and digestive processes

Opening-up approach—clear one’s mind in order to receive new experiences

Concentrative meditation—actively concentrate on an object, word, or idea, called a mantra Koan—a riddle, such as “What is the sound of one hand

clapping?” Mindfulness meditation—pay attention to one’s

feelings, thoughts, and sensations Being in the moment Being mindful, but not judgmental


Psychoactive Drugs

Psychoactive drugs—any substance that alters mood, perception, awareness, or thought Includes coffee, cigarettes, and alcohol


Three Categories of Psychoactive Drugs

Depressants—act on the central nervous system (CNS) to suppress bodily processes Alcohol, sedative-hypnotic drugs, opioids

Stimulants—act on the CNS to increase bodily processes Caffeine, nicotine, cocaine, amphetamines

Hallucinogens—produce sensory or perceptual distortions called hallucinations LSD, marijuana


Psychoactive Drugs and the Brain

Psychoactive drugs activate a reward learning pathway, or “pleasure pathway,” in the brain. Reward-deficiency syndrome—pleasure

pathway is not activated readily by daily events, so these people are prone to abuse drugs


Copyright

Copyright © 2012 John Wiley & Sons Canada, Ltd. All rights reserved. Reproduction or translation of this work beyond that permitted by Access Copyright (The Canadian Copyright Licensing Agency) is unlawful. Requests for further information should be addressed to the Permissions Department, John Wiley & Sons Canada, Ltd. The purchaser may make back-up copies for his or her own use only and not for distribution or resale. The author and the publisher assume no responsibility for errors, omissions, or damages caused by the use of these programs or from the use of the information contained herein.

chapter 6: consciousness. chapter outline 1. when we are awake: conscious awareness 2. preconscious...

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