Sleep!!!

1. Sleep!!! 2/2/11

2. Test Your Knowledge DeMarco has been diagnosed as being in a minimally conscious state. Which of the following behaviors is DeMarco most likely to exhibit? • Higher levels of consciousness including the ability to identify his family members • Deliberate movements such as following a pencil with his eyes • Opening and closing his eyes, but with no awareness of his surroundings • No EEG brain activity Which of the following would be the best example of consciousness? • Jose suffered a brain injury and is comatose. • Jeri is in deep sleep. • Gerard is savoring the taste of a fine wine. • Ivana is “zoning” out and sits staring out the window. A split-brain patient is shown a frog in her left visual field. She is asked to identify what she sees. She would most likely be able to: • Draw the frog with her left hand • Draw the frog with her right hand • Say what she saw • Say what she saw and then point with her right hand

3. Goals for the lecture • To understand the stages of sleep • Have a broad understanding of sleep disorders • Evaluate which dream theory is most consistent with your personal opinion about dreams

4. Sleep • An altered state of consciousness • Brain is still active and somewhat aware • Electroencephalogram (EEG) = a machine that measures brain activity; shows us variations in consciousness

5. EEG Activity • Waking • Beta Waves: Irregular electrical activity; short, frequent brain signals; Characterizes wakefulness • Alpha Waves: Slower, more synchronous brain activity; Characterizes relaxed states • Stage 1: Theta waves; light sleep; Stage 2: Theta waves; Sleep spindles; K-Complexes • Stages 3 & 4: Delta waves (large, regular brain patterns); Called slow-wave sleep; Dreams are non-narrative, dull, mundane; Can involve experiencing anxiety-provoking situations (night terrors) • REM (Rapid Eye Movement) Sleep: EEG similar to wakefulness; Narrative dreaming, vivid, emotionally-charged; Paralysis of muscles; Signs of sexual arousal

6. Sleep cycle

7. Sleep Disorders • Insomnia – difficulty falling or staying asleep • Sleep Apnea – person stops breathing while asleep • REM behavior disorder – person acts out dreams while sleeping (normal muscle paralysis disabled) • Somnambulism – sleepwalking

8. Narcolepsy • Sleep attack: Falling asleep uncontrollably during normal waking hours • Cataplexy: Complete paralysis occurs during waking (the physical part of REM sleep intruding upon wakefulness) • Fully conscious • Triggered by strong emotional reactions or physical exertion • Sleep paralysis: Paralysis occurring just before a person falls asleep or right after a person wakes up • Hypnagogic hallucinations: Vivid dreams while lying awake, paralyzed (the mental part of REM sleep intruding upon wakefulness)

9. Functions of Sleep • Restoration • Allows brain and body to repair themselves • Circadian cycles; adaptive • Keep animals/humans quiet and inactive during times of the day that are most dangerous • Facilitates learning • Neural connections are consolidated and strengthened during sleep • Slow wave sleep and REM sleep are important

11. Theories of Dreaming • Wish Fulfillment (Freud) • “The interpretation of dreams is the royal road to a knowledge of the unconscious activities of the mind.” • Coping/Problem-Solving • Threat rehearsal • Work through everyday issue • Activation-Synthesis Hypothesis • Due to neuronal activity, which we then interpret

12. For Next Time…. • Read p. 158-175 • Exam 1 in one week