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ATC Psychology Chapter 9 “Consciousness”

ATC Psychology Chapter 9 “Consciousness”. Consciousness is the awareness of both external stimuli and one’s own mental activity. Analyzing Consciousness. The scientific study of consciousness began with Wilhelm Wundt. Today, three questions dominate the study of consciousness:

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ATC Psychology Chapter 9 “Consciousness”

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  1. ATC Psychology Chapter 9 “Consciousness” Consciousness is the awareness of both external stimuli and one’s own mental activity.

  2. Analyzing Consciousness • The scientific study of consciousness began with Wilhelm Wundt. • Today, three questions dominate the study of consciousness: • What is the relationship between the mind and the body? • What is the nature of consciousness? • What is the relationship between mental activity and consciousness?

  3. Some Functions of Consciousness • The conscious brain experiences a representation of the sensory world that is the result of many complex nonconscious computations. • It has access to the results of these computational processes but not the processes themselves.

  4. Levels of Consciousness Mental activity that you are aware of occurs at the conscious level of experience.

  5. Nonconscious Mental activity can occur outside of consciousness at the nonconscious level, physiological processes that you cannot consciously monitor without aid of biofeedback occur.

  6. The Cognitive Unconscious Preconscious- contains everything that can easily be brought into consciousness. Other mental activities that can alter thoughts, feelings, and actions but are more difficult to bring into awareness are said to be in the unconscious or subconscious.

  7. Mental Processing Without Awareness • The impact and limitations of consciousness can be seen by studying mental processing that occurs without consciousness. • Under anesthesia, people may still sense the world and form lasting memories, but without awareness of having done so.

  8. Mere Exposure Effect The mere exposure effect is the tendency to like previously encountered stimuli more than new ones, even if you are not aware of which stimuli are new to you and which are old.

  9. Priming Priming occurs when you respond to a stimulus faster or more accurately after having encountered it before. It occurs even if you cannot consciously recall the previous stimulus encounter.

  10. One can learn certain cognitive problem-solving strategies without even being aware that the strategies exist.

  11. The Neuropsychology of Consciousness Brain Damage may exaggerate the human capacity for mental processing without conscious awareness.

  12. Hemi-neglect In hemi-neglect, brain damaged patients are unaware of one side of their world, but continue to receive and process sensory information from the neglected side.

  13. Prosopagnosia • Prosopagnosia, usually caused by temporal lobe damage, is an inability to recognize faces, despite being able to recognize other items using vision or other modalities. • Prosopagnosics may not even recognize their own face in the mirror. • With no conscious recognition of faces, prosopagnosics still discriminate between familiar and unfamiliar faces with eye movements. EEG activity and autonomic arousal.

  14. Visual Form Agnosia • Patients with visual form agnosia have no conscious awareness for an object’s visual orientation or size. • Yet, they can still reach and grasp objects, properly guiding movements and correctly accommodating grip to fit the object’s size.

  15. Blindsight Without conscious awareness for even the fact that visual stimuli have occurred, blindsight patients (whose blindness is caused by visual cortex injury) can “guess” an object’s location, direction of movement, or color.

  16. Anterograde Amnesia People with anterograde amnesia (often due to hippocampal damage) have difficulty forming new memories. In fact, they do acquire new skills, but cannot consciously recall any of the practice sessions.

  17. Levels of Consciousness States of consciousness are variations in the nature of mental processing that may or may not be available to awareness.

  18. Levels of Consciousness • Levels of consciousness are variations in the quantity (i.e. how much?) of awareness one has for whatever mental events are occurring. • Mental events that you are currently aware of exist at the conscious level.

  19. At the Nonconscious level are mental events which cannot be experienced consciously. • Example: We cannot directly “know” about brain modulation of blood pressure. • Biofeedback, you learn which conscious sensory cues accompany a nonconscious process. This permits you to indirectly infer when nonconscious events occur.

  20. Cognitive Unconscious The cognitive unconscious contains mental activities that are not conscious but can either become conscious or influence conscious experience.

  21. Preconscious Level • Preconscious level processing is not itself consciously experienced, but can easily and quickly be brought into conscious experience. • Example: If asked what color your socks are, you can easily bring the answer into consciousness, even though you were not thinking about this information prior to the question.

  22. Sigmund Freud • Hypothesized an unconscious level, containing impulses (mostly sexual and aggressive) and unacceptable thoughts, feelings, and memories of which one is seldom aware. • Non-Freudians call this the subconscious level, in which important, but normally inaccessible, mental processes take place. • As a violent crime victim you may not recall the mugger’s car license plate, but with help of special techniques you may be able to later recall it.

  23. States of Consciousness • States of consiousness are variations in what mental processes occur, independent of how much awareness you have of them. • It is a qualitative distinction of how your mind is currently working. • Sleep, wakefulness, drug-induced states, meditation, and hypnosis.

  24. Active States • In active states, you intentionally direct and manipulate mental activity. • In passive states, your mind wanders and allows various mental process to “come to mind.” • People are most often in a waking state, where attention and arousal dictate the mental processes reaching awareness at any moment. • In an altered state of consciousness, changes, in mental processes are sufficient for you or others to note significant differences from the waking state. • Different cultures place different values on waking versus altered states.

  25. Sleeping and Dreaming • Stages of Sleep • Electroencephalograms (EEGs), which measure brain activity, show “brain waves” whose height (amplitude) and speed (frequency) reflect variations in behavioral and mental processes. EEGs and other physiological measures help divide sleep into stages.

  26. Stages of Sleep In Stage 0 one is relaxed with eyes closed, but awake. EEG is mixed but includes alpha waves, rhythmic waves at 8-12 cycles per second.

  27. Quiet Sleep • During quiet sleep (slow-wave sleep), sleepers breathe deeply while showing a calm heart beat, and low blood pressure. • Stage 1, the first true sleep stage, shows irregular EEG similar to waking alertness. • Stage 2, EEG adds sleep spindles (bursting high frequency waves) and K complexes (a high amplitude peak and valley). • Stage 3 EEG adds high amplitude, low frequency delta waves. • Stage 4, the EEG shows over 50% delta waves

  28. Active Sleep • Also called rapid eye movement (REM) or paradoxical sleep, resembles an awake state with its fast EEG, high heart rate, rapid breathing, and high blood pressure. • Eyelids are closed (although the eyes move), but muscle tone decreases to virtual paralysis. • About 80% of al dreams occur in REM

  29. Sleep Cycles Sleepers cycle through the sleep stages four to six times a night, with a typical pattern of 1-2-3-4-3-2-REM. Each cycle is about 90 minutes; deep sleep (stage 3 and 4) dominates early in the night, whereas stage 2 and REM dominate later.

  30. Sleep and Age • Sleep declines with age, averaging 16 hours a day at infancy and declining to an average of 6 hours a day by age 70. Most of the decrease occurs in REM sleep. • Teenage sleep?

  31. Sleep Disorders Insomnia, the most common sleeping problem, occurs when a person is tired during the day because of trouble falling asleep or staying asleep.

  32. Insomnia • Insomnia may be hard to quantify. Insomniacs tend to underestimate their actual sleeping time. • Sleeping pills or alcohol relieve insomnia only temporarily. And can be dangerous and addictive. • Other approaches include biofeedback, relaxation training, and stress management. • Insomnia is linked to mental illness, although it is not clear if it causes or is caused by such problems.

  33. Narcolepsy • In narcolepsy, a person switches abruptly and suddenly from an active, sometimes emotional waking state to few minutes of REM sleep. • The loss of muscle tone during REM causes collapse during the attack, and immobility for a few minutes after regaining wakefulness. • The cause is unknown but may have a partial genetic basis. • Treatment with stimulants, and napping.

  34. Sleep Apnea • In sleep apnea, breathing stops, briefly awakening the sleeper to restart breathing. These awakenings are not remembered, but do disrupt the normal sleep cycle. In the morning, therefore, victims do not feel well rested. • Apnea can be caused by a problem with the windpipe or with brainstem breathing control mechanism.

  35. Sudden Infant Death Syndrome • SIDS occurs when a sleeping infant stops breathing and suffocates. Its cause is unknown. • As many as 52 % of apparent SIDS cases are accidental suffocations when babies sleep with soft cushions.

  36. Nightmares Nightmares are frightening dreams that occur in REM Sleep.

  37. Night Terrors Night Terrors, occurring in quiet sleep, are horrific dreams that abruptly awaken a person in a state of intense fear.

  38. Sleepwalking Sleepwalking starts primarily in non-REM sleep, most commonly during childhood. Contrary to myth, there is no special danger in waking a sleep walker.

  39. REM Behavior Disorder • REM Behavior Disorder is a loss of the paralysis that usually occurs in REM sleep. • As a result, a sleeper may appear to act out dreams, sometimes even attacking a sleep partner in the process. • Clonazepam controls 90% of cases.

  40. Why Do People Sleep? • Many biological processes show a circadian rhythm—cycling about every 24 hours. • These rhythms are linked, or entrained to environmental cues such as light, but can continue even without them. • Neurons of the suprachiasmatic nucleus (SCN), hypothalamus, appear to act as a built-in biological clock. • Inputs from the eyes may entrain the SCN neurons. • SCN neurons may drive circadian rhythms elsewhere in the brain.

  41. Jet Lag • Jet lag is a pattern of fatigue, irritability, and sleeping problems when you travel across time zones • Similar problems affect people who change between day and night work shifts • It is generally easier to change cycles by going to sleep later than by going to sleep earlier. • Exposure to properly times bright light can reset the biological clock.

  42. Functions of Sleep • Sleep deprivation for even as long as a week causes fatigue, irritability, and poor alertness, but no other serious effects. • The night after sleep deprivation, people generally sleep only twice as much as usual and awaken with no side effects. • The night after sleep deprivation, people tend to spend a greater proportion of time in REM sleep (REM Rebound).

  43. REM Sleep Function REM sleep shuts off the brain’s norepinephrine-releasing neurons, thought to underlie waking alertness. REM sleep may help the brain develop and test synaptic connections. Infants sleep. REM sleep seems to solidify daytime learning. Non-REM sleep may serve a restorative function, helping get the body ready for the next day’s activity.

  44. Dreams and Dreaming • The mind is active throughout sleep. • Dreams differ in that they are story-like and last several seconds to minutes. • Dreams may be organized or chaotic, realistic or bizarre. Like all mental activity they sometimes offer creative solutions to problems.

  45. Everyone Dreams All people, including those who are blind, dream every night. Remembering a dream depends on how you sleep and when you awaken.

  46. Dream Content Daytime activity affects dream content. It may be possible to consciously control dreams during luciddreaming, in which the sleeper is aware of dreaming while a dream is happening.

  47. Why Do People Dream? Non-human mammals also dream. Dreams may be a fundamental mammalian activity to consolidate learning of high personal or survival value. Freud saw dreams as disguised clues to the unconscious wishes and impulses that cause waking problems. Some view dreams as meaningless byproducts of random neural activity during REM sleep.

  48. Hypnosis Hypnosis is an altered state of consciousness brought on by special techniques and typified by responsiveness to suggestion and changes in experience and behavior.

  49. Experiencing Hypnosis Hypnosis is brought no by a hypnotist gradually focusing a subject’s attention on a restricted often monotonous set of stimuli.

  50. Hypnosis and Participation • You cannot be hypnotized unwillingly, and even some willing subjects cannot be hypnotized. • Those with high hypnotic susceptibility process information quickly and easily, tend to fantasize, and have active imaginations.

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