1. Module 23 Sleep Patterns and Sleep Theories
Unit 5 States of Consciousness

2. Biological Rhythms and Sleep
Circadian Rhythm: regulates bodily rhythms including temp and sleep over 24 hr cycle
Ultradian
Infradian
Thinking and memory sharpest at YOUR daily peek
Altered by age and experiences
Owls and Larks

3. Sleep Stages 90 minute cycles with 4 distinct stages
Measure changes in sleep stages using EEG on scalp, chin, corner of eyes
Alpha Waves: slow, when you’re awake but calm
Beta Waves: awake and alert
Sleep: natural loss of consciousness

4. 4 Stages of Sleep
NREM-1: twilight sleep, slowed breathing irregular brain waves. Lasts a few minutes.
Can have hallucinations: false sensory experiences (sense of falling)
Also known as hypnagogic sleep
Can be incorporated into memories
NREM-2: lasts about 20 minutes
See sleep spindles: rapid, rhythmic brain waves
Can be easily awakened but are asleep

6. 4 Stages Cont. 4. REM: contains most vivid dreams.
3. NREM-3: lasts about 30 min.
Deep sleep, delta waves
4. REM: contains most vivid dreams.
Paradoxical: brain looks like it’s awake but muscles are relaxed
Heart rate increases, rapid breathing, eyes dart, genital arousal=beginning of dreams
Active motor cortex but brainstem blocks messages
Sleep paralysis

8. Stages Cont. Hour into cycle, you go back down the cycle
NREM-1  NREM-2  NREM-3 NREM-2 REM
Spend half of the night’s sleep in NREM-2
At 90 minutes, NREM-3 grows shorter and disappears
20-25% in REM sleep each night

9. What Affects Our Sleep Patterns?
Genetically and culturally influenced
Bright lights “tweak” circadian rhythms
Suprachiasmatic nucleus (SCN): in hypothalamus causes pineal gland to decrease melatonin due to light

10. Sleep Theories 5 Reasons for Sleep Protects Recuperative
Restore/Rebuild memories
Creative Thinking
Growth