Sleep & Dreams Unit 4

Circadian Rhythm Biological clock that governs how people function 1. Sequence of bodily changes (body temp, blood pressure, sleep and wake) 2. Usually operates on 24-hour day Circadian Rhythm

Stages of Sleep Measured with EEG: 2 types (REM & NREM) 1. N-REM (Non-rapid eye movement) Stage 1: Lightest Sleep; Alpha Waves- drowsy, slow eye movement, muscle activity stabilizes Stage 2: Theta Waves Stage 3 & 4: Delta waves = your deepest sleep

Stages of Sleep… 2. REM (Rapid Eye Movement) Waves resemble wakefulness- CNS active Increased heart rate, blood pressure, O2 consumption Muscle activity suppressed

The Sleep Cycle We pass through all stages in 90-minute cycle 4-6 cycles each night Most slow wave sleep occurs early Most REM occurs in 2nd half of night

Sleep Disorders A. Insomnia: Difficulty in falling asleep, lasts 2-3 days Treatment by sleeping pills effective for only 2 weeks Learned/conditioned insomnia caused by bad sleeping habits Cognitive arousal (worry/anxiety) a cause Standard treatments: muscle relaxation techniques, hypnosis, sleep restriction therapy, psychotherapy

Sleep Disorders… B. Sleep Apnea Breathing interruption that occurs during sleep Occurs when air passages are blocked Do not automatically start breathing until they sit up and gasp for air

Sleep Disorders… C. Narcolepsy Suddenly fall asleep regardless of time or surroundings Suddenly fall into REM sleep and awaken feeling refreshed Treatment: drug therapy and frequent naps

Dreams DREAMS

Dreams frequently occur in REM Cycle REM = a kind of sleep that occurs at intervals during the night -Characterized by rapid eye movements and faster pulse & breathing 15% REM awakenings fail to report dream C. 20% Non-REM do report dreaming at all D. Infants: unable to tell if they’re dreaming First dreams possibly occur at 2-3 years

Dream Recall On average we have slightly less than one dream per night recalled Some people recall 2-3 each night Some recall a dream every 4-6 months B. Experiments show visual memory correlates with dream recall

Dream Recall… C. Freud: Repression Hypothesis Forgetting results of taboo content which is potentially threatening to the ego Even remembered (manifest) content is disguised as unacceptable (latent/taboo) content

Table Talk Discuss a dream that you remember having last night? A dream from last week? A dream from last month? What do you think the dream(s) meant?