Thinking About Psychology: The Science of Mind and Behavior 2e

1. Thinking About Psychology: The Science of Mind and Behavior 2e Charles T. Blair-Broeker Randal M. Ernst, borrowed happily

2. Consciousness Chapter

3. Sleep, Dreams, and Body Rhythms

4. Consciousness • Awareness of yourself and your environment.

5. Consciousness: Personal Awareness • Awareness of Internal and External Stimuli • Levels of awareness • William James& stream of consciousness (endless flow of ideas), one stream of conscious mental activity seems to blend into another, effortlessly and seamlessly. Despite the changing focus of our awareness, our experience of consciousness as unbroken helps provide us with a sense of personal identity that has continuity from one day to the next. • Freud & the unconscious – submerged thoughts, feelings, wishes and drives. He believed the interpretation of dreams is the royal road to knowledge of unconscious activities. First to recognize different levels of awareness.

6. Biological and Environmental “Clocks” Regulate Consciousness • You probably notice that your level of consciousness varies through out the day. Two big examples: • Mental alertness • Sleep/wake cycle • Daily cycles are called circadian rhythms. (combination of two Latin words for about and day) • Over 100, many are closely syncronized

7. Circadian Rhythms • Biological rhythms that occur approximately every 24 hours • Example: Sleep-wake cycle, temperature, release of growth hormone, urine production, strength, peak senses, sensitivity to pain, Peak allergic sensitivity… See table 4.1

8. Suprachiasmatic Nucleus – cluster of neurons in the hypothalamus, the master biological clock that controls the circadian rhythm. • Keeping circadian rhythms requires environmental cues.

9. Light levels  retina  suprachiasmatic nucleus of hypothalamus  pineal gland  secretion of melatonin • Melatoninmakes you feel sleepy and peaks between 1am and 3am (temp the lowest). Bright light decreases production. • In the absence of light our bodies drift to our intrinsic rhythm, which is about 25 hours, and our normal circadian rhythms become desynchronized. (cave example) • Normally for the sleep-wake cycle body temperature, and melatonin cycles are closely related. • Jet lag interferes with thinking, concentration, and memory. On top of physical and mental fatigue, depression and irritability occur. It can take a full week to adjust! • Blind people

10. Hypothalamus & the SCN • Sleep control center in the brain • Monitors changes in light or dark in the environment • Changes levels of hormones in the body

11. Sleep and Circadian Rhythms • Play “Sleep and Circadian Rhythms” (6:09) Module #13 from The Brain: Teaching Modules (2nd edition).

12. Ultradian Rhythms • Biological rhythms that occur more than once each day. • Sleep cycles • Concentration cycles, some say the human mind can focus and concentrate for 90 to 120 minutes at a time and work with sustained energy after which our attention span decreases and we need to take a break for at least 15 -20 minutes before we can focus once again.

13. Infradian Rhythms • Biological rhythms that occur once a month or once a season (animals – hybernation) • Example: Women’s menstrual cycle

14. Sleep and Sleep Deficit

15. Why We Sleep

16. Reasons for Sleep • Two primary reasons: • Adaptive Theory: keep us protected from the dangers of the night, aka Evolutionary Theory • Restorative Theory: recuperate from the wear and tear of the day, NREM restores the body and REM restores the mind • Adenosine, inhibitory neurotransmitter, believed to play a role in promoting sleep and suppressing arousal, with levels increasing with each hour an organism is awake. • During the day GABA communicates excitatory messages at night GABA communicates inhibitory messages. Interesting that GABA is usually inhibitory. http://science.howstuffworks.com/caffeine3.htm

17. Sleep Deprivation Effects • Decreases efficiency of immune system functioning • Safety and accident issues • Contributes to hypertension, impaired concentration, irritability, etc. • “The Sleep-Deprived Emotional Brain” fMRI scans show the amygdala reacting 60% more strongly.

18. Major accidents caused by sleep deprivation.. • 1979 Three Mile Island, PA– accidental melting of the core of nuclear reactor, no deaths, effects are still debated • 1986Chernobyl, Ukraine (USSR) – nuclear explosion.. 31 deaths… • 1989 Exxon Valdez – oil spill in Alaska • http://healthysleep.med.harvard.edu/healthy/matters/consequences/sleep-performance-and-public-safety • http://library.thinkquest.org/25553/english/difficult/society/accidents.shtml

19. Sleep Deprivation • Complete deprivation • 3 or 4 days max • Partial deprivation or sleep restriction (one night’s sleep, or continued reduction of sleep) • impaired attention, reaction time, coordination, and decision making • accidents: Chernobyl, Exxon Valdez • Selective deprivation • REM: rebound effect

20. Sleep Deprivation

21. Figure 5.9 Effect of sleep deprivation on cognitive performance

22. Sleep Deprivation as punishment http://www.time.com/time/nation/article/0,8599,1892897,00.html

23. Random Sleep Facts • http://facts.randomhistory.com/facts-about-sleep.html

24. Sleep/Waking Research • Instruments: • Electroencephalograph – brain electrical activity • Electromyography– muscle activity • Electrooculograph– eye movements • Other bodily functions also observed

25. Electroencephalograph (EEG) • Machine that amplifies and records waves of electrical activity that sweep across the brain’s surface • Electrodes placed on the scalp measure the waves

26. The Electroencephalograph:A Physiological Index of Consciousness • EEG – monitoring of brain electrical activity • Brain-waves • Amplitude (height) • Frequency (cycles per second) • Beta (13-24 cps) • Alpha (8-12 cps) • Theta (4-7 cps) • Delta (<4 cps)

27. Table 5.1 EEG Patterns Associated with States of Consciousness

28. Sleep Stages, REM, and Dreaming:The Stages of Sleep

29. REM (rapid eye movement) – active sleep, heightened body and brain activity with dreaming • NREM – quiet sleep, body’s physiological functions and brain activity slow down (4 stages)

30. 1. NREM sleep immediately, and you progress through 4 NREM sleep stages. • Brain and body activity decreasing with each 2.REM sleep (increased activity and dreaming) • Total cycle about 90 minutes

31. Stage 1 Sleep • Breathing is slowed. • Brain waves become irregular. • It is easy to wake the person, who will insist they are not asleep. • Rarely lasts longer than 5 minutes • alpha & theta brain waves • Hypnagogic jerks can happen • Imaging, but not true dreams

32. Stage 1

33. Stages of Sleep

34. Stage 1

35. Stage 2 Sleep • Brain wave cycle slows. • First time through stage 2 last about 20 minutes. • Onset of true sleep. • Sleep spindles (brief bursts) • K complexes (sudden spikes) • Rhythmical breathing • Small muscle twitches

36. Stage 2

37. Stages 3 and 4 Sleep • Slow wave sleep • When delta brain waves makes up more than 20% of activity, stage 3. When more than 50%, stage 4. • During the 20-40 minutes spent in the night’s first episode delta waves will make come to make up 100% • Heart rate, blood pressure, and breathing drop to their lowest • Hard to wake, typically when sleep walking occurs • First time through stage 4 is about 30 minutes and is where one gets rejuvenated. • Can take 15 min to gain full waking consciousness

38. Stage 3

39. Stage 4

40. Figure 5.5 An overview of the cycle of sleep

42. Sleep • Play “Sleep: Brain Functions” (11:12) Module #14 from The Brain: Teaching Modules (2nd edition).

43. REM Sleep • Rapid eye movement (REM Sleep) as eyes move quickly back and forth • Vivid dreaming occurs in REM sleep • The first REM tends to be brief, increasing in each cycle

44. REM Sleep

45. Paradoxical Sleep • During REM sleep brain wave patterns are similar to when a person is awake • Pulse and breathing quickens. • REM sleep is sometimes called paradoxical sleep as one’s physiology is close to that of being awake but the brainstem blocks all muscle movement

46. REM Sleep • Play “REM Sleep and Dreams” (8:23) Module #15 from The Brain: Teaching Modules (2nd edition).

47. Typical Night’s Sleep

48. Stage 4/REM Changes

49. Sleep Changes through Life

50. Dreams • By adulthood you dream about 2 hours per night, you’ll devote more than 50,000 hours or six years of your life to dreaming!! • Sleep thinking v dreaming • 4-5 dreaming episodes each night • Usually the main character with at least one other person, sometimes the observer • 1st REM 10 minutes, avg 30 min per cycle, last cycle can be 40 minutes • Read “The Dreaming Brain: Turning REM On and Off” • REM-off neurons produce norepinephrine and serotonin which suppress REM. REM-on neurons produce acetylcholine which promote REM.