1. Rice/Psych

2. Muscles usually ready to respond to danger relax and our senses grow dull. “The behavior patterns involved in sleep are glaringly, almost insanely, at odds with common sense”- psychologist Christopher Evans Let’s see what happens during sleep before we talk about why it is needed Risky but Necessary

3. Until the 1950s, little was known until…. Nathaniel Kleitman (only person, @ the time, to spend entire career studying sleep) Question- Do slow, rolling eye movements that characterize the onset of sleep continue through the night? Discovery- Eye movements became rapid! Vocab- Rapid Eye Movement (REM)- sleep periods characterized by eye movement, loss of muscle tone, and vivid dreams. How did they find this? EEG (measures brain’s electrical activity- then correlated with eye movements with changes in brain wave patterns. Our Sleeping Brain

4. It alternates with non-REM sleep every 90 mins or so… REM lasts a few minutes to an hour- Average= 20 mins When they start, the electrical activity in the brain resembles that of alert wakefulness! More info to come -----> REM Sleep

5. Non-REM sleep go through distinct stages, associated with a particular brain-wave pattern. When you first climb into bed, close your eyes, relax… your brain emits bursts of alpha waves. On an EEG- alpha waves have a regular, slow rhythm and a high amplitude (height). Gradually… these… slooowww doowwwwnnn and you drift into the Land of Nod- passing through four stages, each deeper than the previous one… To the right  Stages we will be walking through. Label them now! Non-REM Sleep Stages

6. 1.Your brain waves (Alpha Waves) become small and irregular, you feel yourself drifting on the edge of consciousness, in a state of light sleep. If awakened, you may recall fantasies or a few visual images. Stage 1

7. 2. Your brain emits occasional short bursts of rapid, high-peaking waves called sleep spindles. Minor noises probably won’t disturb you. Stage 2

8. 3. In addition to the waves characteristic to Stage 2, your brain occasionally emits delta waves, very slow waves with very high peaks. Your breathing and pulse have slowed down, your muscles are relaxed, and you are hard to rouse. Stage 3

9. 4. Delta waves have now largely taken over, you are in deep sleep. It will probably take vigorous shaking or a loud noise to wake you. Oddly, though, if you walk in your sleep, this is when you are likely to do so. No one yet knows what causes sleepwalking, which occurs more often in children than adults, but it seems to involve unusual patterns of delta-wave activity. Stage 4

10. After this sequence took place, you move back up the ladder from Stage 4 to 3 to 2 to 1. BUT Stage 1 does not become drowsy/wakeful as expected. Instead, your brain begins to emit long bursts of very rapid, somewhat irregular waves. Your heart-rate increases, your blood-pressure rises, your breathing is faster and irregular, and you may have small twitches in your face or fingers. Most skeletal muscles go limp, preventing your aroused brain from producing physical movement. YOU ENTERED THE REALM OF REM! These Stages took 30-45 mins… now what? We sleep longer than that!

11. B/c our brain is super active and our body is entirely inactive, the most vivid dreams happen during REM sleep. People have reported to have had dreams even when they were awakened during non-REM sleep, but they are shorter, less vivid, more realistic (except in the hour or so before a person wakes up) 82% reported dreaming when awakened from REM 51% reported dreaming when awakened from non-REM Sometimes when a sleeper wakes up, a curious phenomenon occurs: Emerge from REM sleep b4 muscle paralysis fully disappears  become aware of the inability to move :Z  have a “waking dream”- “see” hallucinations (ghosts/aliens) More on REM Sleep

12. REM and non-REM continue through the night… Stage 3 & 4 become shorter or even disappear. REM periods tend to get longer and closer together  why you may dream your alarm clock is going off Cycles are far from regular may bounce from Stage 4 directly to 2, back to REM time between REM varies Graph next slide-------------------------> Night sleep pattern

13. All in a good night sleep:

14. If you wake people every time they lapse into REM sleep, nothing Dramatic will happen. When finally allowed to sleep normally- people will spend a much longer time in the REM phase. It will be hard to wake them. It is as if they are getting something they were deprived of… LET ME DREAM! Almost all mammals experience REM sleep except the bottlenose dolphin and the porpoise. Though it seems unlikely that rats and anteaters lack the cognitive abilities to construct dreams, and moles hardly move their eyes at all – EEG patterns show REM sleep. Reasons for REM = Controversial

15. So we can’t explain why REM sleep happens.. But let’s see why we sleep in general… *Eliminate waste from Muscles *Repair Cells *Strengthen the Immune System *Recover Abilities Lost throughout the Day Mental Benefits: *Sleep may be necessary for “consolidation”- a process by which the synaptic changes associated with recently stored memories become durable and stable *Improvements in Memory are closely associated with REM sleep So don’t lose sleep studying- study and then sleep! *Thus it also helps Enhance Problem Solving (relies on info in stored memory) Why do we Sleep?

16. We will discuss disorders on a different day.. But here are some problems. *We are a fast-paced modern society that often don’t sleep as much as we need Daytime drowsiness also interferes with reaction time, concentration, and learning ability Levels or hormones necessary for normal muscle development and proper immune-system functioning decline (so staying home to sleep when sick is good) Most can get along well after a day or two of sleeplessness, but sleep deprivation that lasts more than four days or longer becomes uncomfortable then unbearable. In animals- forced sleeplessness leads to infections and death! A 51 year old man abruptly began to lose sleep- after sinking deeper and deeper into exhausted stupor, he developed a lung infection and died. An autopsy showed he had lost almost all the large neurons in two areas of the thalamus that had been linked to sleep and hormonal circadian rhythms Mental Consequences of Sleeplessness

18. You must record AT LEAST 5 Days worth of sleep journal entries tracking time sleeping and dreams! (Real Easy) Some apps can help with that: Suggested- Free: Sleep on It (notes/mood/checklist/track waking up in the middle of the night) 1. Record how many hours you slept 2. Record as much of your dream as you can remember -Exclude anything above PG-13 Due the day of your test (TBA) but you will definitely have enough days to do it…. Weekends are included! Next Class- we will be looking at Dreaming and Dream Theories! Sleep Tracking Journal

19. 1.The functioning of the biological clock governing circadian rhythms is affected by the hormone_____________. 2.Why do people get jet lag? _________MATCHING ___________________________________________________________ 3. REM periods _____ 4. Alpha _____ 5. Stage 4 Sleep _____ 6. Stage 1 Sleep _____ _____________________________________________________________________________ 7. Sleep is necessary for normal: a) physical and mental functioning, b) mental but not physical functioning, c) physical but not mental functioning 8. T or F :Most people need more than 6 hours of sleep a night. 9. T or F:Only REM sleep has been associated with dreaming and memory consolidation. 10. Your sleep journals are due the day of the _____________, including _______ of sleep, and any notes of ___________ you can remember when you wake up. Consciousness/Sleep Review/Practice a.Delta waves and talking in one’s sleep b.Irregular brain waves and light sleep c.Relaxed but awake d.Active brain but inactive muscles Melatonin Biological Clock desyncronization from crossing Time Zones d.d. c. a.a. b. test hours dreams