The Mind and Consciousness

1. The Mind and Consciousness 4

2. Questions to Consider: I. How Is the Conscious Mind Experienced? II. What Is Sleep? III. What Is Altered Consciousness? IV. How Do Drugs Affect Consciousness?

3. I. How Is the Conscious Mind Experienced? • Consciousness Is a Subjective Experience • There are Variations in Conscious Experience • Splitting the Brain Splits the Conscious Mind • Unconscious Processing Influences Behavior • Brain Activity Produces Consciousness

4. 1. Consciousness is a Subjective Experience • Subjectivity and “qualia”: each of us experiences consciousness subjectively • We cannot know if any two people experience the world in exactly the same way • Two components: the contents of consciousness and level of consciousness • Access to information

5. Figure 4.2 One difficult question related to consciousness is how people experience qualia, the phenomenological percepts of the world. For instance, does red look the same to everyone who has normal color vision?

6. 1. Consciousness Is a Subjective Experience • Brain imaging research has shown how particular regions of the brain are activated by particular types of sensory information

7. Figure 4.3

8. 1. Consciousness Is a Subjective Experience • Miguel Nicolelis and his research on rhesus monkeys • John Donoghue and BrainGate

9. 2. There Are Variations in Conscious Experience • Conscious experience is a continuous stream of thoughts that often floats from one thought to another • Consciousness is a unified and coherent experience—there is a limit to how many things you can be conscious of at the same time

10. 2. There Are Variations in Conscious Experience • Consciousness and coma • The persistent vegetative state • Full consciousness • Between these two is the minimally vegetative state • Ethical issues surround the use of brain evidence for end-of-life decisions

11. 3. Splitting the Brain Splits the Conscious Mind • When you split the brain, do you split the mind? • the corpus callosum connects the brain’s hemispheres • severing the corpus callosum produces split brain • Differences in right and left hemisphere function

12. Figure 4.7 Images from the left side go to the brain’s right hemisphere, and images from the right side go to the left hemisphere.

13. 3. Splitting the Brain Splits the Conscious Mind • Left hemisphere: dominant for language • Right hemisphere: dominant for spatial relationships

14. Figure 4.8 (Left)

15. Figure 4.8 (Right)

16. 4. Unconscious Processing Influences Behavior • The case for unconscious influence: • Priming effects • Subliminal perception

17. 5. Brain Activity Produces Consciousness • Global Workspace Model

18. Dr. Carl HartColumbia UniversitySpeaking on Methamphetamine: Using Data to Decrease Hysteria Sponsored By: The Psychology Department Upperman African-American Cultural Center Center for the Support of Undergraduate Research and Fellowships Friday, February 11, 2011 3:30 – 5:00 pm in Randall Library Auditorium

19. II. What is Sleep? • Sleep Is an Altered State of Consciousness • Sleep Is an Adaptive Behavior • Sleep and Wakefulness Are Regulated by Multiple Neural Mechanisms • People Dream while Sleeping

20. 1. Sleep Is an Altered State of Consciousness • The difference between being awake and being asleep has as much to do with conscious experience as with biological processes. • Using an EEG, researchers have measured the patterns of electrical brain activity during the different stages of normal sleep: • Stage 1 is characterized by theta waves • Stage 2 is characterized by K complex • Stages 3 and 4 are characterized by delta waves • REM sleep occurs after approximately 90 minutes of sleep

21. Figure 4.13 Using an EEG, researchers measuredthese examples ofthe patterns of electricalbrain activity during different stages of normalsleep.

22. Figure 4.14 This chartillustrates the normal stages ofsleep over thecourse ofthe night.

23. 2. Sleep Is an Adaptive Behavior • Researchers have proposed three general explanations for sleep’s adaptiveness: • Restoration • Circadian cycles • The facilitation of learning

24. 2. Sleep Is an Adaptive Behavior • Restoration: restorative theory suggests sleep allows the brain and body to rest and repair themselves • Sleep deprivation causes mood problems and a decrease in cognitive performance • Microsleeps result from sleep deprivation

25. 2. Sleep Is an Adaptive Behavior • Circadian cycles: brain and other physiological processes are regulated into patterns • Body temperature • Hormone levels • Sleep/wake cycles • Sleep is an evolutionary adaptation to avoid danger

26. 2. Sleep Is an Adaptive Behavior • The facilitation of learning: sleep is part of the process of strengthening neural connections that serve as the basis of learning • Slow-wave sleep • REM sleep

27. 3. Sleep and Wakefulness Are Regulated by Multiple Neural Mechanisms • Multiple neural mechanisms are involved in producing and maintaining circadian rhythms of sleep • A tiny structure in the brain called the pineal gland secretes melatonin, a hormone that travels through the bloodstream and affects various receptors in both the body and the brain

28. Figure 4.17 The biological clock signals the pineal gland tosecrete melatonin, which affects bodily statesrelated to being tired.

29. 4. People Dream while Sleeping • Dreams occur in REM and non-REM sleep, although the dreams’ contents differ in the two types of sleep: • REM sleep: bizarre, emotion-filled, visual/auditory hallucinations, often illogical • Non-REM sleep: dull, mundane content and activities

30. Figure 4.18

31. 4. People Dream while Sleeping • What do dreams mean? • 2 theories: • Freud: manifest/latent content • Hobson: activation-synthesis hypothesis • Freud: dreams have hidden content that represent unconscious conflicts • Manifest content: way we remember dream • Latent content: what the dream symbolizes

32. 4. People Dream while Sleeping • What do dreams mean? • Alan Hobson: the activation-synthesis hypothesis • Random neural stimulation activates mechanisms that normally interpret visual input • The mind synthesizes activity in visual/motor neurons with stored memories

33. III. What Is Altered Consciousness? • Hypnosis Is Induced through Suggestion • Meditation Produces Relaxation

34. 1. Hypnosis Is Induced through Suggestion • Hypnosis involves a social interaction during which a person, responding to suggestions, experiences changes in memory, perception, and/or voluntary action • Psychological scientists generally agree that hypnosis affects some people, but they do not agree on whether it produces a genuinely altered state of consciousness

35. 1. Hypnosis Is Induced through Suggestion • Theories of hypnosis: • Sociocognitive theory of hypnosis: hypnotized people behave as they expect hypnotized people to behave • Dissociation theory of hypnosis: the hypnotic state is an altered, trance-like state where conscious awareness is dissociated from other aspects of consciousness

36. Figure 4.19 This PET image from one of Stephen Kosslyn’s studies shows thatareas in the visual cortex associated with color perception are activated more whenhypnotized participants are told to imagine color—a finding that suggests the brainfollows hypnotic suggestions.

37. 2. Meditation Produces Relaxation • Meditation is a mental procedure that focuses attention on an external object or on a sense of awareness • Through intense contemplation, the meditator develops a deep sense of calm tranquility

38. IV. How Do Drugs Affect Consciousness? • People Use—and Abuse—Many Psychoactive Drugs • Alcohol Is the Most Widely Abused Drug • Addiction Has Psychological and Physical Aspects

39. 1. People Use—and Abuse—Many Psychoactive Drugs • Many of the same psychoactive drugs used for medical treatment are also used for “recreational” purposes • Drug use alters physical sensations, levels of consciousness, thoughts, moods, and behaviors in ways that users believe are desirable • Recreational drug use sometimes can have negative consequences

40. 1. People Use—and Abuse—Many Psychoactive Drugs • Marijuana • Most widely used illegal drug • THC (tetrahydrocannibinol) produces relaxed mental state, uplifted/contented mood, and perceptual/cognitive distortions • Concentration of cannabinoid receptors in the hippocampus (memory impairment) • Medicinal properties are controversial

41. 1. People Use—and Abuse—Many Psychoactive Drugs • Stimulants • Activate sympathetic nervous system (increased heart rate and blood pressure) • Improve mood • Cause restlessness and disrupt sleep • Cocaine • Amphetamines (speed, meth, etc.) block reuptake and increase release of dopamine

42. 1. People Use—and Abuse—Many Psychoactive Drugs • MDMA • Known commonly as “ecstasy” • Similar effects as stimulants, with slight hallucinations • Less dopamine release, more serotonin release • Opiates • Heroine, morphine, codeine • Increased dopamine activation in the nucleus accumbens, binding with opiate receptors • Highly addictive due to dual activation of dopamine and opiate receptors

43. 2. Alcohol Is the Most Widely Abused Drug • Americans have a love/hate relationship with alcohol • On the one hand, moderate drinking is an accepted aspect of normal social interaction and may even be good for health • On the other hand, alcohol is a major contributor to many of our societal problems, such as spousal abuse and other forms of violence

44. 2. Alcohol Is the Most Widely Abused Drug • Gender Differences in Alcohol Consumption across Cultures • Men twice as likely to report binge drinking, chronic drinking, recent alcohol intoxication • Four key factors: • Power • Sex • Risks • Responsibilities

45. 2. Alcohol Is the Most Widely Abused Drug • Expectations • Alcohol reduces anxiety • Alcohol increases social skills, sexual pleasure, confidence, power • Reality • Large doses of alcohol result in negative moods and focus on problems and anxieties • Alcohol impairs motor processes, information processing, mood, sexual performance • Learned beliefs about intoxication influence behavior

46. 3. Addiction Has Psychological and Physical Aspects • Addiction is a physiological state in which failing to ingest a substance leads to symptoms of withdrawal, a state characterized by anxiety, tension, and craving • Physical dependence is associated with tolerance, so that a person needs to consume more of the substance to achieve the same subjective effect • Dopamine activity in the limbic system is central to addiction and rewarding properties of drugs

47. 3. Addiction Has Psychological and Physical Aspects • Psychological dependence refers to habitual and compulsive substance use despite the consequences • People can be psychologically dependent without showing tolerance or withdrawal • Individuals can be psychologically dependent on behaviors like gambling or shopping