Chapter 3- Consciousness and the Two-Track Mind PDF

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Summary from the psychology textbook by David G Myers...

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Chapter 3: Consciousness and the Two-Track Mind Section 1- Brain States and Consciousness Question 1- What is the place of consciousness in psychology’s history? (Defining Consciousness)

Definition

Review

Consciousness: Our awareness of ourselves and our environment.

At its beginning, psychology was “the description and explanation of states of consciousness”. Neuroscience advances linked brain activity to sleeping, dreaming, and other mental states. This awareness allows us to assemble information from many sources as we reflect on our past and plan for our future. Evolutionary psychologists presume that consciousness offers a reproductive advantage. Since 1960, under the influence of cognitive psychology, neuroscience, and cognitive neuroscience, our awareness of ourselves and our environment- our consciousness- has reclaimed its place as an important area of research. Consciousness was displaced by the study of observable behaviour for a long while. Advances in neuroscience made it possible to relate brain activity to various mental states; as a result, psychologists once again affirmed the importance of cognition

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Question 2- What is the “dual processing” being revealed by today’s cognitive neuroscientists? (The Biology of Consciousness: Cognitive Neuroscience and Dual Processing: The Two-Track

Definitions Cognitive Neuroscience: The interdisciplinary study of the brain activity linked with cognition (including perception, thinking, memory, and language). Dual Processing: The principle that information is often simultaneously processed on separate conscious and unconscious tracks. Blindsight: A condition in which a person can respond to a visual stimulus without consciously experiencing it.

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Even in a motionless body, the researchers concluded, the brain- and the mind- may still be active. Many cognitive neuroscientists are exploring and mapping the conscious function of the cortex. Some neuroscientists believe that conscious experience arises from synchronized activity across the brain. A particular brain region becomes active with a particular conscious experience. Perception, memory, thinking, language, and attitudes all operate on two levels- a conscious, deliberate “high road” and an unconscious, automatic “low road”. The high road is reflective, the low road is intuitive. A visual perception track enables us “to think about the world”- to recognize things and to plan future actions. A visual action track guides out moment-to-moment movement. Being intensely focused on an activity increases your total brain activity no more than 5% above its baseline rate. Your brain waves jump about 0.35 seconds before you consciously perceive your decision to move. The actual decision to move occurs when the brain activity crosses a threshold, which happens to coincide with the average “time of awareness of intention to move” (about 0.15 seconds before the movement). In everyday life, we mostly function like an automatic camera, but with a manual (conscious) override.

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Chapter 3: Consciousness and the Two-Track Mind

Question 3- How does selective attention direct our perceptions? (Selective Attention)

Review

Definitions

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Parallel Processing: The processing of many aspects of a problem simultaneously; the brain’s natural mode of information processing for many functions. Selective Attention: The focusing of conscious awareness on a particular stimulus. Inattentional Blindness: Failing to see viable objects when our attention is directed elsewhere. Change Blindness: Failing to notice changes in the environment.

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Section 2- Sleep and Dreams

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Parallel processing enables your mind to take care of routine business. Sequential processing is best for solving new problems. Consciousness is nature’s way of keeping us from thinking and doing everything at once. Your five senses take in 11,000,000 bits of information per second, of which you consciously process about 40. The cocktail part effect- your ability to attend to only one voice among many. Brain activity decreases an average 37% when a driver is attending to conversation. Distraction effect is mostly cognitive rather than visual. Your conscious mind is in one place at a time. People’s blindness extends to their own choices. The dual-track mind is active even during sleep. Solving new problems requires conscious attention and is usually best served by sequential processing. Change deafness is when a person focuses on the words being spoken and do not notice a change in the speaker. Some stimuli are so powerful they demand our attention, causing us to experience popout.

Question 4- What is sleep? (Sleep)

Definition

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Sleep: Periodic, natural loss of consciousness- as distinct from unconsciousness resulting from a coma, general anesthesia, or hibernation. (Adapted from Dement, 1999).

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Sleep is the irresistible tempter to whom we inevitably succumb. Even when you are deeply asleep, your perceptual window is open a crack. EEG recordings confirm that the brain’s auditory cortex responds to sound stimuli even during sleep.

Question 5- How do our biological rhythms influence our daily functioning? (Biological Rhythms and Sleep: Circadian Rhythm)

Definition Circadian Rhythm: The biological clock; regular body rhythms (for example, of temperature and wakefulness) that occur on a 24-hour cycle

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As morning approaches, body temperature rises then peaks during the day, dips for a time in early afternoon (when many people take siestas), and begins to drop again in the evening. Night owls tend to be smart and creative. Morning types tend to do better in school, to take more initiative, and to be less vulnerable to depression. Age and experiences can alter circadian rhythm patterns, resetting our biological clock. When people are at their daily peak in circadian arousal, thinking

Chapter 3: Consciousness and the Two-Track Mind

Question 6- What is the biological rhythm of our sleep and dreaming stages? (Biological Rhythms and Sleep: Sleep Stages and REM Sleep)

Definitions 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. Hallucinations: False sensory experiences, such as seeing something in the absence of an external visual stimulus. Delta Waves: The large, slow brain waves associated with deep sleep.

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Order of Sleep Stages Normally we move through NREM-1, then NREM-2, then NREM-3, then back up through NREM-2 before we experience REM sleep.

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Sleep overtakes us and consciousness fades as different parts of our brain’s cortex stops communicating. About every 90 minutes, we cycle through four distinct sleep stages. The period of fast, jerky eye movements were accompanied by energetic brain activity. The transition is marked by slowed breathing and the irregular brain waves of non-REM stage 1 sleep. During this brief NREM-1 sleep you may experience fantastic images resembling hallucinations. These hypnagogic sensations may later be incorporated into your memories. You then relax more deeply and begin about 20 minutes of NREM-2 sleep, with its periodic sleep spindles- bursts of rapid, rhythmic brain-wave activity. During this slow wave sleep, which lasts for about 30 minutes, your brain emits large, slow delta waves and you are hard to awaken. For about 10 minutes, your brain waves become rapid and saw toothed, more like those of the nearly awake NREM-1 sleep. During REM sleep your heart rate rises, your breathing becomes rapid and irregular, and every half-minute or so your closed eyes dart around in momentary bursts of activity. Except during very scary dreams, your genitals become aroused during REM sleep. In young men, sleep-related erections outlast REM periods, lasting 30 to 45 minutes on average. Your brain’s motor cortex is active during REM sleep, but your brainstem blocks its messages. By morning, we have spent 20 to 25% of an average night’s sleep, some 100 minutes, in REM sleep. We spend about 600 hours a year experiencing some 1500 dreams, or more than 100,000 dreams over a typical lifetime- dreams swallowed by the night but not acted out, thanks to REM’s protective paralysis. Aserinksy discovered the rhythm of sleep cycle when he noticed the eyes of a child moving rapidly while sleeping. During NREM-3 (slow wave sleep) a child may wet the bed.

Chapter 3: Consciousness and the Two-Track Mind

Question 7- How do biology and environment interact in our sleep patterns? (Biological Rhythms and Sleep: What Affects Our Sleep Patterns?) Definition

Review

Suprachiasmatic Nucleus (SCN): A pair of cell clusters in the hypothalamus that control circadian rhythm. In response to light, the SCN causes the pineal gland to adjust melatonin production, thus modifying our feelings of sleepiness.

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Sleep patterns are genetically and culturally influenced. Bright morning light tweaks the circadian clock by activating light-sensitive retinal proteins. These proteins control the circadian clock by triggering signals to the brain’s suprachiasmatic nucleus. The SCN does its job partly by causing the brain’s pineal gland to decrease its production of the sleep-inducing hormone melatonin in the morning and to increase it in the evening. Artificial light delays sleep. Newborns spend nearly 2/3 of their day asleep, while adults spend no more than 1/3. Sleep patterns among identical twins are very similar. People now sleep less than what they did a century ago.

Question 8- What are sleep’s functions? (Why Do We Sleep?)

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Psychologists believe sleep may exist for five reasons: o Sleep protects. o Sleep helps us recuperate. o Sleep helps restore and rebuild our fading memories of the day’s experiences. o Sleep feeds creative thinking. o Sleep supports growth. Those who didn’t try to navigate around dark cliffs were more likely to leave descendants. tissue. xperiences stored in the hippocampus and shifts them for hormone that is necessary for muscle development. a night’s sleep, produces the human growth hormone final hours of a long night’s sleep, help strengthen the ng the “muscle memories” learned while practicing a sport. ng, Maas and Robbins advise, when the body’s natural dvised, because they increase the risk of injury and rob o be avoided because the arousal disrupts falling asleep. r piano playing, benefits when practiced shortly before dance of chemical free radicals that are toxic to neurons.

and what are the major sleep disorders? d Sleep Disorders)

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Insomnia: Recurring problems in falling or staying asleep. Narcolepsy: A sleep disorder characterized by l

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The brain keeps an accurate count of sleep debt for at least two weeks. College and university students are especially sleep deprived

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Definition Dream: A sequence of images, emotions, and thoughts passing through a sleeping person’s mind. Dreams are notable for their hallucinatory imagery, discontinuities, and incongruities, and for the dreamer’s delusional acceptance of the content and later difficulties remembering it.

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REM dreams are vivid, emotional, and often bizarre- so vivid we may confuse them with reality. We spend six years of our life in dreams. 8 in 10 dreams are marked by at least one negative event or emotion. Only 1 in 10 dreams among young men and 1 in 30 among young women had sexual content. We do not remember recorded information playing while we are soundly asleep. We usually dream of ordinary events and everyday experiences, most involving some anxiety or misfortune. Most dreams incorporate traces of previous days’ experiences. While we sleep, our mind monitors stimuli in the environment.

Question 11- What functions ha (Why W Definitions 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). REM Rebound: The tendency for REM sleep to increase following REM sleep deprivation (created by repeated awakenings during REM sleep).

Theories for Dreaming 1.

Freud’s wish-fulfilment (dreams as a psychic safety valve). 2. Information-processing (dreams sort the day’s events and form memories). 3. Physiological function (dreams pave neural pathways). 4. Neural activation (REM sleep triggers random neural activity that the mind weaves into stories). 5. Cognitive development (dreams reflect the dreamer’s developmental stage).

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Freud considered dreams the key to understanding our inner conflicts. The information processing perspective proposed that dreams may help sift, sort, and fix the day’s experiences in our memory. The brain regions that buzzed as rats learned to navigate a maze, or as people learning to perform a visual-discrimination task, buzzed again during later REM sleep. Sacrificing sleep time to study actually worsens academic performance, by making it harder the next day to understand class material or do well on a test. Stimulating experiences preserve and expand the brain’s neural pathways. According to “activation-synthesis theory”, dreams are the brain’s attempt to synthesize random neural activity. PET scans of sleeping people also reveal increased activity in the emotional-related limbic system (in the amygdala) during emotional dreams. Frontal lobe regions responsible for inhibition and logical thinking seem to idle, which may explain why our dreams are less inhibited than we are when awake. Dreams stimulate reality by drawing on our concepts and knowledge. Withdrawing REM-suppressing sleeping medications also increases REM sleep, but with accompanying nightmares.

Chapter 3: Consciousness and the Two-Track Mind Theory

Explanation

Critical Considerations

Freud’s wishfulfilment

Dreams preserve sleep and provide a “psychic safety valve”- expressing otherwise unacceptable feelings: contain manifest (remembered) content and a deeper layer of latent content (a hidden meaning). Dreams help us sort out the day’s events and consolidate our memories.

Lacks any scientific support; dreams may be interpreted in many different ways.

Informationprocessing

Physiological function Neural activation Cognitive developmen t

Regular brain stimulation from REM sleep may help develop and preserve neural pathways. REM sleep triggers neural activity that evokes random visual memories, which our sleeping brain weaves into stories. Dream content reflects dreamer’s level of cognitive development- their knowledge and understanding. Dreams stimulate our lives, including worst-case scenarios.

But why do we sometimes dream about things we have not experienced and about past events? This does not explain why we experience meaningful dream. The individual’s brain is weaving the stories, which still tells us something about the dreamer. Does not propose an adaptive function of dreams.

Section 3- Drugs and Consciousness Question 12- What are substance use disorders, and what roles do tolerance, withdrawal, and addiction play in these disorders? (Tolerance and Addiction)

Definitions

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Substance Use Disorder: Continued substance craving and use despite significant life disruption and/or physical risk. Psychoactive Drug: A chemical substance that alters perceptions and moods

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Odds of Getting Hooked After Using Various Drugs

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Tobacco: 32% Heroin: 23% Alcohol: 15% Marijuana: 9%

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A drug’s overall effect depends not only on its biological effects, but also on the user’s expectations, which vary with social and cultural contexts. With continued use of alcohol and some other drugs (not marijuana), the user’s brain chemistry adapts to offset the drug effect (a process called neuroadaptation). Those with a substance use disorder may exhibit impaired control, social disruption, risky behaviour, and the physical effects of tolerance and withdrawal. Tolerance is when a person requires a larger dose of the drug to achieve the desired effect. Withdrawal is significant discomfort accompanying attempts to quit. Continued use may lead to addiction, which is the compulsive craving of drugs or certain behaviours (such as gambling) despite known adverse consequences.

When is Drug Use a Disorder? Diminished Control 1. Uses more substance, or for longer, than intended. 2. Tries unsuccessfully to regulate use of substance. 3. Spends much time acquiring, using, or recovering from effects of substance. 4. Craves the substance. Diminished Social Functioning 5. Use disrupts commitments at work, school, or home. 6. Continues use despite social problems. 7. Causes reduced social, recreational, and work activities. Hazardous Use 8. Continues use despite hazards. 9. Continues use despite worsening physical or psychological problems. Drug Action 10. Experiences tolerance (needing more substance for the desired effect).

11. Experiences withdrawal when attempting to end use Question 13- How has the concept of addiction changed?

Chapter 3: Consciousness and the Two-Track Mind (Addiction)

Definitions

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Tolerance: The diminishing effect with regular use of the same dose of a drug, requiring the user to take larger and larger doses before experiencing the drug’s effect. Addiction: Compulsive craving of drugs or certain behaviours (such as gambling) despite known adverse consequences. Withdrawal: The discomfort and distress that follows discontinuing an addictive drug or behaviour.

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Psychologists debate whether the concept of addiction has been stretched too far, and whether adductions are really as irresistible as commonly believed. Addictions can be powerful, and many with addictions do benefit from therapy or group support. The addiction-as-disease-needing-treatment idea has been extended to a host of excessive, driven behaviours, but labeling a behaviour doesn’t explain it.

Why Addiction May Not Be as Irresistible as Commonly Believed Addiction may not be as irresistible as commonly believed. For example, the following are not true: a) Taking a psychoactive drug automatically leads to addiction. b) A person cannot overcome an addiction without professional help.

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The addiction-as-disease-needing-treatment model is applicable to a broad spectrum of pleasure-seeking behaviours.

Question 14- What are depressants, and what are their effects? (Types of Psychoactive Drugs: Depressants)

Alcohol

Definitions Depressants: Drugs (such as alcohol, barbiturates, and opiates) that reduce neural activity and slow body functions. Alcohol Use Disorder: (Popularly known as alcoholism) alc...