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Consciousness and the Two-Track Mind

Chapter 3. Consciousness and the Two-Track Mind. PSYCHOLOGY. David G. Myers C. Nathan DeWall Twelfth Edition. Chapter Overview. Basic Consciousness Concepts Sleep and Dreams Drugs and Consciousness. The Place of Consciousness in Psychology’s History.

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Consciousness and the Two-Track Mind

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  1. Chapter 3 Consciousness and theTwo-Track Mind PSYCHOLOGY David G. Myers C. Nathan DeWall Twelfth Edition

  2. Chapter Overview • Basic Consciousness Concepts • Sleep and Dreams • Drugs and Consciousness

  3. The Place of Consciousness in Psychology’s History • 1880s: Psychology defined as description and explanation of states of consciousness • First half of 20th century: Direct observation of behavior • 1960s: Consciousness nearly lost; science of behavior • After 1960s: Study of consciousness altered by hypnosis, drugs, and meditation; importance of cognition • Today: Under the influence of cognitive psychology, neuroscience, and cognitive neuroscience, consciousness reclaims its place as an important area of research

  4. Brain States and Consciousness • Consciousness • Awareness of self and environment • Cognitive neuroscience • Interdisciplinary study of the brain activity linked with cognition (including perception, thinking, memory, and language)

  5. Different States of Consciousness

  6. The Biology of Consciousness • Cognitive neuroscientists • Explore and map conscious cortex function and can sometimes “read” minds • Suggest consciousness arises from synchronized brain activity Evidence of Awareness? When asked to imagine playing tennis or navigating her home, a vegetative patient’s brain (top) exhibited activity similar to a healthy person’s brain (bottom).

  7. Consciousness and Selective Attention • Selective attention • Focusing conscious awareness on a particular stimulus • Inattentional blindness • Failure to see visible objects when attention is directed elsewhere • Change blindness • Failure to notice changes in the environment, a form of inattentional blindness

  8. Selective Attention and Accidents • Rapid toggling between activities is common today. • Sixty percent of U.S. drivers read or sent a text message or viewed a phone map while driving in the last month (Glicklich, 2016). • Multitasking distracts brain resources allocated to driving; brain activity decreases, on average, 37 percent when conversation occurs (Just et al., 2008). • Cell-phone use increases accident risk fourfold. • An 18-month video camera study of the driving habits of long-haul truckers found that when they were texting, their risk of a collision increased 23 times (Olson et al., 2009).

  9. Change Blindness • While a man (in red) provides directions to a construction worker, two experimenters rudely pass between them carrying a door. During this interruption, the original worker switches places with another person wearing different-colored clothing. Most people, focused on their direction giving, do not notice the switch (Simons & Levin, 1998).

  10. Dual Processing: The Two-Track Mind (part 1) • Dual processing • Information is often simultaneously processed on separate conscious (explicit) and unconscious (implicit) tracks. • Perceptions, memory, attitudes, and other cognitions are affected. • Blindsight awareness • A person can respond to a visual stimulus without consciously experiencing it.

  11. When the Blind Can “See” • In this compelling demonstration of blindsight and the two-track mind, researcher Lawrence Weiskrantz trailed a blind-sight patient down a cluttered hallway. • Although told the hallway was empty, the patient meandered around all the obstacles without any awareness of them.

  12. Dual Processing: The Two-Track Mind(part 2) • Parallel processing • Processing many aspects of a problem simultaneously; the brain’s natural mode of information processing for many functions • Sequential processing • Focusing conscious awareness on a particular stimulus

  13. What Is Sleep? • Sleep • Periodic, natural loss of consciousness—as distinct from unconsciousness resulting from a coma, general anesthesia, or hibernation (adapted from Dement, 1999)

  14. True or False? • When people dream of performing some activity, their limbs often move in concert with the dream. • Older adults sleep more than young adults. • Sleepwalkers are acting out their dreams. • Sleep experts recommend treating insomnia with an occasional sleeping pill. • Some people dream every night; others seldom dream.

  15. False! • When people dream of performing some activity, their limbs often move in concert with the dream. • Older adults sleep more than young adults. • Sleepwalkers are acting out their dreams. • Sleep experts recommend treating insomnia with an occasional sleeping pill. • Some people dream every night; others seldom dream.

  16. Sleep and Dreams • Biological rhythms • 24-hour biological clock • 90-minute sleep cycle for younger adults • Circadian rhythm • Internal biological clock of 24-hour cycle of day and night • Body temperature rises as morning approaches, peaks during the day, dips in the early afternoon, and begins to drop in the evening • Altered by age and experience

  17. Measuring Sleep Activity • Sleep researchers measure brain-wave activity, eye movements, and muscle tension by using electrodes that pick up weak electrical signals from the brain, eyes, and facial muscles (Dement, 1978).

  18. Sleep (part 1) • Brain waves and sleep stages • The beta waves of an alert, waking state and the regular alpha waves of an awake, relaxed state differ from the slower, larger delta waves of deep NREM-3 sleep. • Although the rapid REM sleep waves resemble the near-waking NREM-1 sleep waves, the body is more aroused during REM sleep than during NREM sleep.

  19. Sleep (part 2) • Alpha waves • Relatively slow brain waves of a relaxed, awake state • Hallucinations • False sensory experiences, such as seeing something in the absence of an external visual stimulus • Delta waves • Large, slow brain waves associated with deep sleep

  20. REM Sleep • REM (rapid eye movement) • Sleep stage during which vivid dreams commonly occur • REM rebound • Tendency for REM sleep to increase following REM sleep deprivation

  21. Sleep Stages

  22. What Affects Our Sleep Patterns? • Sleep patterns are genetically and culturally influenced. • Bright morning light activates light-sensitive proteins that trigger the suprachiasmatic nucleus (SCN) to cause decreased production of melatonin in the morning and increased production in the evening. • Social jet lag may occur when sleep routines are disrupted during weekends.

  23. Why Do We Sleep? • Sleep may have played a protective role in human evolution by keeping people safe during potentially dangerous periods. • Sleep helps restore and repair damaged neurons. • REM and NREM-2 sleep help strengthen neural connections that build enduring memories. • Sleep promotes creative problem solving the next day. • During deep sleep, the pituitary gland secretes a growth hormone necessary for muscle development.

  24. The Biological Clock

  25. Sleep Loss • After a succession of 5-hour nights, we accumulate a sleep debt that cannot be satisfied by one long sleep. • In a 2013 Gallup poll, 40 percent of Americans reported getting 6 hours or less sleep per night (Jones, 2013).

  26. Effects of Sleep Loss • Sleep deprivation • Causes fatigue and irritability • Impairs concentration, productivity, and memory consolidation • Can lead to depression, obesity, joint pain, a suppressed immune system, and slowed performance with a greater vulnerability to accidents

  27. How Sleep Deprivation Affects Us

  28. Less Sleep = More Accidents

  29. Major Sleep Disorders • Insomnia • Recurring problems in falling or staying asleep • Narcolepsy • Sudden uncontrollable sleep attacks, sometimes lapsing directly into REM sleep • Sleep apnea • Stopping of breathing while asleep; associated with obesity, especially in men • Night terrors • High arousal and appearance of being terrified • Sleepwalking and sleeptalking

  30. Sleep Disorders

  31. Sleep Aids

  32. Dreams (part 1) • Dream: A sequence of images, emotions, and thoughts passing through a sleeping person’s mind

  33. What Do We Dream? • We usually dream of ordinary events and everyday experiences, most involving some anxiety or misfortune. • Daydreams: Familiar details of our life • REM dreams: Vivid, emotional, bizarre • Dreams with negative event or emotion: 8 in 10 dreams • Dreams with sexual imagery: 1 in 10 among young men and 1 in 30 among young women • Dreams incorporating previous days’ experience: Most common

  34. Dreams (part 2) • Why we dream • To satisfy our own wishes • To file away memories • To develop and preserve neural pathways • To make sense of neural static • To reflect cognitive development

  35. Dreams (part 3) • Manifest content • According to Freud, the remembered story line of a dream (as distinct from its latent, or hidden, content) • Latent content • According to Freud, the underlying meaning of a dream (as distinct from its manifest content)

  36. Dream Theories

  37. Dream Theories

  38. Substance Use Disorders • Psychoactive drug • A chemical substance that alters perceptions and moods • Substance use disorder • A disorder characterized by continued substance craving and use despite significant life disruption and/or physical risk

  39. Drugs and Consciousness: Tolerance and Addiction • Tolerance • With repeated use, the desired effect requires larger doses • Addiction • Compulsive craving of drugs or certain behaviors (such as gambling) despite known harmful consequences • Withdrawal • Discomfort and distress that follow the discontinuation of an addictive drug or behavior

  40. What Roles Do Tolerance, Withdrawal, and Addiction Play in Substance Use Disorders? • People with a substance use disorder may exhibit impaired control, social disruption, risky behavior, and the physical effects of tolerance and withdrawal. • Psychoactive drugs alter perceptions and moods. • They may produce tolerance (requiring larger doses to achieve the desired effect) and withdrawal (significant discomfort accompanying attempts to quit). • Continued use may lead to addiction—the compulsive craving of drugs or certain behaviors (such as gambling) despite known adverse consequences.

  41. When Is Drug Use a Disorder? (part 1)

  42. How Has the Concept of Addiction Changed? • Concept of addiction • Extended to cover many behaviors • Degree and scope debated • Addiction as a disease needing treatment • Offered for many driven, excessive behaviors that become compulsive and dysfunctional • APA (2013) manual proposes further study of Internet gaming disorder

  43. Types of Psychoactive Drugs • Depressants • Drugs such as alcohol, barbiturates (tranquilizers), and opiates that calm neural activity and slow body functions • Alcohol acts as a disinhibitor • Slows neural processing and acts as a potent sedative when paired with sleep deprivation • Disrupts memory and has long-term effects on the brain and cognition; impairs growth of synaptic connections • Reduces self-awareness and self-control; produces myopia by focusing on an arousing situation at the expense of normal inhibitions and future consequences

  44. Disordered Drinking Shrinks the Brain • MRI scans show brain shrinkage in women with alcohol use disorder (left) compared with women in a control group (right).

  45. Alcohol Expectancy Effects • Expectations influence behavior • Attribution of social behaviors or sexual responses to alcohol releases inhibitions. • Fourteen intervention studies with college students lowered the participants’ positive expectations of alcohol and reduced drinking in the ensuing month. • Alcohol use disorder • Alcohol use marked by tolerance, withdrawal, and a drive to continue problematic use

  46. Depressants (part 1) • Barbiturates • Depress the activity of the central nervous system, reducing anxiety but impairing memory and judgment • Can impair memory and judgment; potentially lethal when combined with alcohol • Nembutal, Seconal, and Amytal

  47. Depressants (part 2) • Opiates • Include opium and its derivatives, such as codeine, morphine and heroin; addictive • Constrict the pupils, slow breathing, and cause lethargy • Depress neural activity, temporarily lessening pain and anxiety • Cause withdrawal when ingestion is stopped

  48. Stimulants • Stimulant drugs • Include caffeine and nicotine, as well as the more powerful amphetamines, cocaine, Ecstasy (MDMA), and methamphetamine • Excite neural activity and speed up body functions • Causes dilation of pupils, increased heart and breathing rates, rise in blood sugar, and drop in appetite • Often increase energy and self-confidence

  49. Nicotine • The stimulating and highly addictive psychoactive drug in tobacco • Signals the central nervous system to release a flood of neurotransmitters • Diminishes appetite, boosts alertness and mental efficiency, calms anxiety, and reduces sensitivity to pain • Produces challenging acute craving and withdrawal symptoms that contribute to relapse after attempts to quit use

  50. Where There’s Smoke . . . The Physiological Effects of Nicotine • Nicotine reaches the brain within 7 seconds, twice as fast as intravenous heroin. • Within minutes, the amount in the blood soars.

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