1. VARIATIONS IN CONSCIOUSNESS
Is this reality or just someone’s imagination of reality?
VARIATIONS IN CONSCIOUSNESS

2. CONSCIOUSNESS The awareness of internal and external stimuli
Also includes:
Awareness of self as unique
Awareness of experiences

3. VARIATIONS IN LEVELS OF AWARENESS
William James---stream of consciousness
Freud believed that stream had depth (unconscious)
Conscious and unconscious are levels of consciousness

4. CONSCIOUSNESS AND BRAIN ACTIVITY
Consciousness is not centered in one structure
EEG is the best measurement
Records brain waves
4 principle waves: beta, alpha, theta, and delta

5. BIOLOGICAL RHYTHMS AND SLEEP
Biological rhythms: periodic fluctuations in physiological functioning
Circadian rhythms: 24 hour biological cycles found in humans and many other species

6. IGNORING CIRCADIAN RHYTHMS
Quality of sleep
Crossing time zones causes jet lag
Going to bed a couple of hours later affects rhythm

7. THE SLEEP AND WAKE CYCLE

8. CONDUCTING SLEEP RESEARCH
Use EEG
Electromyograph (EMG): records muscular activity and tension
Electrooculograph (EOG): records eye movements

9. STAGES OF SLEEP---Stage 1
1: lasts 1-7 minutes; drowsiness; breathing and heart rate decrease; muscle activity declines
Hypnic jerks: brief muscular contractions
Primarily theta waves

10. STAGES OF SLEEP---STAGE 2
10-25 minutes
Sleep spindles: higher-frequency brain waves
Brain waves become higher in amplitude and slower in frequency

11. STAGES OF SLEEP---STAGES 3 AND 4
Lasts c. 30 minutes
Slow-wave sleep: high amp, low frequency delta waves prominent
After: cycle reverses
Before reaching stage one again, ….

12. REM SLEEP 5th stage Irregular breathing and pulse Virtually paralyzed
Beta waves
High-frequency, low amp brain waves, and vivid dreaming
Non-REM (nREM): stages 1-4

13. REPEATING THE CYCLE Usually repeat c. 4 times
REM periods get longer; peak at min.
NREM periods get shorter
Young adults: 60% in light sleep (1 and 2); 20% in slow wave sleep (3 and 4); 20% in REM

14. AGE AND SLEEP Infants: 6-8 times in 24 hrs; 16+ hrs total 50% in REM
As age increases, deep sleep decreases in amt
Total sleep increases w/age

15. CULTURE AND SLEEP Co-sleeping: children and parents sleep together
Discouraged in western societies
Napping is cultural; siesta cultures

16. NEURAL BASES OF SLEEP
Reticular Formation important in sleep and wakefulness
Ascending reticular activating system (ARAS): afferent fibers running through the RF that influence physiological arousal

17. NEURAL BASES OF SLEEP CONTINUED
Pons assoc. with REM sleep
Areas in medulla, thalamus, hypothalamus, and limbic system assoc. with control of sleep and waking
NT’s involved: ACh, serotonin, norepinephrine, dopamine, and GABA

18. EVOLUTIONARY BASES OF SLEEP
Conserve energy
Reduce exposure to predators
Helps to restore energy and other bodily resources
Which do you believe?

19. SLEEP DEPRIVATION
Complete deprivation negatively effects mood, cognitive and perceptual-motor tasks
Difficult to go past 3 or 4 days w/o sleep
Partial deprivation: losing substantially less sleep over a period of time; very common

20. SLEEP DEPRIVATION CONTINUED
Selective deprivation
Repeated disruption of sleep
Experiments show rebound effect: making up time in stages where sleep was interrupted

21. INSOMNIA Insomnia: chronic problems in getting adequate sleep
3 main types
1: difficulty in falling asleep
2: difficulty maintaining sleep
3: persistent early-morning waking
--assoc. w/ daytime fatigue, impaired functioning, reduced productivity, increased health problems

22. INSOMNIA Sleep state misperception: pseudoinsomnia
Causes: anxiety, stress, depression, various health problems
Treatment: sedatives for short term solution

23. OTHER SLEEP DISORDERS
Narcolepsy: sudden onset of sleep during normal waking periods
Sleep apnea: frequent, reflexive gasping for air that disrupts sleep
Nightmares: anxiety-arousing dreams that lead to awakening, usually from REM
Night terrors: abrupt awakenings from NREM sleep accompanied w/intense autonomic arousal and feelings of panic
Sleepwalking: walking around while asleep