EXPLORING PSYCHOLOGY EIGHTH EDITION IN MODULES David Myers PowerPoint Slides Aneeq Ahmad Henderson State University Worth Publishers, © 2011

Consciousness and the Two-Track Mind

Dual-Processing, Sleep, and Dreams Module 5

The Brain and Consciousness  Dual Processing  Selective Attention Sleep  Biological Rhythms and Sleep  Why Do We Sleep?  Sleep Disorders  Dreams

Consciousness is our awareness of ourselves and our environment. In addition to normal, waking awareness, it can come to us in altered states. States of Consciousness Bill Ling/ Digital Vision/ Getty Images Christine Brune Stuart Franklin/ Magnum Photos AP Photo/ Ricardo Mazalan

Dual Processing Through dual processing, we are simultaneously processing information through both conscious and unconscious tracks. Perception, memory, thinking, language, and attitudes all operate on these two levels.

Through selective attention, your conscious awareness focuses on only a very limited aspect of all that you experience. While driving and talking on the phone, your selective attention must shift focus from one to the other, which can make you slower to respond to a demanding situation. Selective Attention

Inattentional Blindness Inattentional blindness refers to the inability to see an object or a person in our midst. Simons & Chabris (1999) showed that half of the observers failed to see the gorilla-suited assistant in a ball passing game.

Change Blindness Change blindness is a form of inattentional blindness in which two-thirds of individuals giving directions failed to notice a change in the individual asking for directions.

Sleep & Dreams Sleep – the irresistible tempter to whom we inevitably succumb. Sleep—the equalizer of presidents and peasants. Sleep—sweet, renewing, mysterious sleep. Mysteries about sleep and dreams have just started unraveling in sleep laboratories around the world.

Biological Rhythms and Sleep Circadian Rhythms occur on a 24-hour cycle and include sleep and wakefulness. Termed our “biological clock,” it can be altered by artificial light. Light triggers the suprachiasmatic nucleus to decrease (morning) melatonin from the pineal gland and increase (evening) it at nightfall.

REM sleep rapid eye movement sleep: a recurring sleep stage during which vivid dreams commonly occur. Also known as paradoxical sleep, because the muscles are relaxed (except for minor twitches) but other body systems are active. Alpha waves: the relatively slow brain waves of a relaxed, awake state. Sleep: periodic, natural loss of consciousness—as distinct from unconsciousness resulting from a coma, general anesthesia, or hibernation. Sleep Stages

Hallucinations, false sensory experiences, can occur during the brief Stage 1 sleep. Delta waves, the large, slow brain waves associated with deep sleep begin in Stage 3 and increase in Stage 4. Sleep Stages

Sleep researchers measure brain-wave activity, eye movements, and muscle tension by electrodes that pick up weak electrical signals from the brain, eye, and facial muscles. Measuring Sleep Activity

The regular alpha waves of an awake, relaxed state are quite different from the slower, larger delta waves of deep Stage 4 sleep. Although the saw-toothed REM sleep waves resemble the near - waking Stage 1 sleep waves, the body is more aroused during REM sleep than during Stage 1 sleep. (From Dement, 1978.) Brain Waves and Sleep Stages

90-Minute Cycles During Sleep With each 90-minute cycle, stage 4 sleep decreases and the duration of REM sleep increases.

Why do we sleep? The Effects of Sleep Loss We spend roughly one- third of our lives sleeping. A sleep-deprived person may experience a depressed immune system, impaired concentration, and a greater vulnerability to accidents. Jose Luis Pelaez, Inc./ Corbis

Canadian Traffic Accidents Frequency of accidents increase with loss of sleep

Sleep Theories 1.Sleep Protects: Sleeping in the darkness when predators loomed about kept our ancestors out of harm’s way. 2.Sleep Helps us Recover: Sleep helps restore and repair brain tissue. 3.Sleep Helps us Remember: Sleep restores and rebuilds our fading memories. 4.Sleep may play a role in the growth process: During sleep, the pituitary gland releases growth hormone. Older people release less of this hormone and sleep less.

1.Insomnia: A persistent inability to fall asleep. 2.Narcolepsy: Overpowering urge to fall asleep that may occur while talking or standing up. 3.Sleep apnea: Failure to breathe when asleep. Sleep Disorders

Children are most prone to:  Night terrors: The sudden arousal from sleep with intense fear accompanied by physiological reactions (e.g., rapid heart rate, perspiration) which occur during Stage 4 sleep.  Sleepwalking: A Stage 4 disorder which is usually harmless and unrecalled the next day.  Sleeptalking: A condition that runs in families, like sleepwalking. Sleep Disorders

Dreams A dream is a sequence of images, emotions, and thoughts passing through a sleeping person’s mind.

Why Do We Dream? To satisfy our own wishes… Freud believed that dreams provide an outlet for otherwise unacceptable feelings. Manifest content: the remembered story line of a dream Latent content: the underlying meaning of a dream

Why We Dream To develop and preserve neural pathways… Some researchers speculate that dreams may serve a physiological function. To make sense of neural static… Other theories propose that dreams erupt from neural activity spreading upward from the brainstem To reflect cognitive development… Others see dreams as part of brain maturation and cognitive development. REM rebound, the tendency for REM sleep to increase following REM sleep deprivation, supports this view.

Dream Theories Summary