Consciousness & Sleep

1. Consciousness & Sleep Today’s Goal: Define the levels of consciousness and the stages of the sleep cycle.

3. How many statements are true for you? • I need an alarm clock to wake me up. • It’s a struggle for me to get out of the bed in the morning. • Weekday mornings I hit the snooze button several times. • I often fall asleep watching TV. • I feel tired, irritable, stressed-out during the week. • I have trouble concentrating & remembering. • I often need to nap during the day. • I often feel drowsy while driving. • I often fall asleep after heavy meals. • I often fall asleep in boring meetings or in warm rooms. • I often sleep extra hours on the weekends. • I fall asleep within five minutes of getting into bed.

4. Consciousness • Awareness of ourselves & environment • Preconscious • Not in immediate awareness, but can easily be brought to conscious level • Nonconscious • Involuntary processes (digestion, respiration, etc.) • Unconscious • Deep, hidden mind (difficult to bring to conscious awareness) • Dual processing (two-track mind) • We function at conscious and unconscious levels at once • Ever get to school and forget driving there?

5. Circadian Rhythm • Biological clock – controls our regular bodily rhythms of 24-hour cycle, keeps body in synch • Suprachiasmatic nucleus (SCN) – regulates gland production of melatonin • Body temperature, blood pressure, metabolism fluctuate

7. Biological clock (in brain) controls circadian rhythms • Makes sure body is in synch

8. Sleep Cycle/Stages • 90 minute cycles • EEG – brain wave activity • Stages 1-4 = NREM sleep • REM sleep

9. Electrooculograms – eye movement • Electromyograms – muscle tension

10. Today’s Goal: Define the levels of consciousness and the stages of the sleep cycle.

11. NREM/REM Sleep • NREM (non-rapid-eye-movement) • 75% of sleep • Restores the body • Stages 3 & 4 decrease in additional sleep cycles • REM (rapid-eye-movement • 25% of sleep • Restores brain • Vivid dreams • Body immobile • Increases in time with additional sleep cycles

12. Awake & alert – Beta waves • Faster, irregular waves • 15-45 peaks per second • Awake but relaxed – Alpha waves • Smooth, regular waves • 10 peaks per sec.

13. NREM Stage 1 • Theta waves • ~10 min. • Transition from wakefulness to sleep • Hypnagogic state – brief dreamlike experience • Hypnic jerks (body shutting down)

14. NREM Stage 2 • Theta waves • Sleep spindles – brief bursts in wave frequency • Info-processing/memory, tuning out noises • K Complexes – brief bursts in wave amplitude (in response to noise)

15. Stages 3 & 4 • Delta waves ~30-40 min. of cycle • Blood pressure drops • Slowed breathing • Tissue growth, repairs • Growth hormone

16. REM Sleep • Paradoxical sleep • Brain is active but body is immobile • Vivid dreams • Cortisol (stress hormone) drops • Helps immune system

17. Sleep Cycle

18. Sleep Cycle

21. Theories of Sleep & Sleep Disorders Today’s Goal: Why do we sleep and what happens when disorders prevent us from getting good sleep?

22. Why Do We Sleep? • Protects • Restore & repair • Making memories • Creative thinking • Growth

23. Sleep Deprivation • Genetic & cultural influences on how much sleep we need • Lack of sleep • Takes a long time to repay sleep debt • Sleep deprivation = weight gain • Suppresses immune system • Effects similar to aging • Fatal accidents • REM rebound  if sleep deprived, spend more time in REM

24. Insomnia

25. Hypersomnia

26. Narcolepsy

27. Sleep Apnea

28. Somnambulism (Sleepwalking)

29. Night Terrors

30. Theories of Dreaming • Freud’s wish-fulfillment Manifest content  storyline of dream Latent content  underlying meaning • Info-processing Sort out day’s events & experiences, make memories

31. Theories of Dreaming • Physiological Brain stimulation develops & preserves neural pathways • Activation-synthesis Random neural firing, our brains create meaning • Cognitive development Reflect person’s cognitive dev. & understanding