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Sleep and Dream states. Consciousness What is consciousness? Consciousness is what goes on between your ears when you are awake? DREAMING is a state of consciousness Altered states of consciousness Sleep, drugs, meditation, hypnosis?. Sleep and wakefulness.
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Sleep and Dream states • Consciousness • What is consciousness? • Consciousness is what goes on between your ears when you are awake? • DREAMING is a state of consciousness • Altered states of consciousness • Sleep, drugs, meditation, hypnosis?
Sleep and wakefulness • Seem different but have a lot in common • In sleep • we may ‘talk’ • we may ‘walk’ • we have memories • we can even plan things! • Sleep patterns vary - average = 7/8 hours per night
Sleep • Disruption of sleep leads to fatigue • What goes on in the brain of a sleeper? • Brain activity can be recorded by an EEG • Electroencephalogram
Sleep and dream states • Every 24 hours we sleep • we spend 30% of our lives asleep • sleep is an active NOT a passive behaviour • Dement and Kleitman (1950s) • the five stages of sleep • National Initiatives • UfI • NGFL • Sector Developments • Connectivity • Local initiatives • Inclusivity and widening participation
The brain and its states... • Waking EEGs - • Desynchronised brain waves • not all chanting together
The stages of sleep • Before sleep • just as we fall asleep • synchronised alpha waves • heart rate slows, temperature falls • muscle tension reduces
The stages of sleep • Stage 1 sleep - alpha waves reduced • less desynchronised brain activity • Stage 2 sleep - synchronised brain activity • larger and slower waves • bursts of sharp ‘spikes’ • (sleep spindles)
The stages of sleep • Stage 3 sleep - slow delta waves • less sleep spindles • heart and breathing rate continue to fall • Stage 4 sleep - only delta waves • arousal threshold high (people are hard to wake up) • 4 stages of Slow Wave Sleep • all synchronised slow wave activity
REM sleep • REM sleep - after about 90 minutes EEG shows SHIFT into fast desynchronised brain activity • heart rate increases • skeletal muscles relaxed (paralysis) • Rapid Eye Movements occur (REM)
REM sleep • REM sleep - 15 minutes in REM sleep then back through stage 2 3 and 4 • this cycle repeats every 90 minutes • 5 or 6 cycles per night • towards morning more REM sleep • we dream in REM sleep, thus dream more in early morning
What is sleep FOR? • The evolutionary theory • All species sleep, thus sleep MUST have a valuable function (survival of the species) • Do animals need sleep? • Rats deprived of sleep die after 21 days • Jouvet - cats & the flower pot technique • (These animals may have died of stress)
Human sleep deprivation? • REM sleep seems important: • The Randy Gardner study • volunteers who are gradually deprived of sleep • (sleep reduced from 8 hours to 2 hours) • pack REM sleep into the time they CAN sleep
Do we only DREAM in REM sleep? • How can we find out? • IDEAS on a post card please!!!!!
Dement and Kleitman • Developed a rigorous and objective test • of the • relationship between REM sleep and dreaming
Dement and Kleitman • Three ways to collect data • First DV • Dream recall during REM and NREM sleep • they woke people up and asked them if they had dreamed
Dement and Kleitman • Three ways to collect data • 2nd DV • Subjective estimate of the duration of dreams CORRELATED to the duration of REM before awakened • they asked people to say how long their dreams had lasted
Dement and Kleitman • Three ways to collect data • 3rd DV- patterns of eye movements were related to the reported dream content • to test whether the movement represented specific expression of the visual dream experience
Dement and Kleitman • Third DV - the criteria • FOUR eye movement patterns • 1 mainly vertical • 2 mainly horizontal • 3 vertical & horizontal • 4 little or none
Dement and Kleitman • Have we all got that? • 3 ways to collect the data (DVs) • self report of dreaming • self report of length of dream - correlated to length of EEG REM • correlation of eye movement to reported dream content
Dement and Kleitman • 9 participants (7 male & 2 female) • only 5 studied intensively • method - a lab experiment • The procedure - Ps asked to refrain from alcohol & caffeine • Report at bed time to sleep lab
Dement and Kleitman • Ps go to bed in quiet room • Electrodes stuck next to eyes to record eye movements • Electrodes stuck to scalp to record brain waves (EEG) • All attached by single wire to EEG (lead wire at top of bed)
Dement and Kleitman • Now - Ps awakened through the night to test their dream recall • 21 awakenings in first 2 hrs of sleep • 29 awakenings in 2nd 2 hrs of sleep • 28 awakenings in 3rd 2 hrs of sleep • 22 awakenings in 4th 2 hrs of sleep
Dement and Kleitman • They were woken by a bell placed next to the bed • when woken the Ps spoke into a recording device near the bed • FIRST - they said whether they had been dreaming • NEXT they said what they were dreaming about (if they could)
Dement and Kleitman • CONTROL • No communication between experimenter and sleeper until after they told of their dream content • in case the experimenter ‘suggested the content’
Dement and Kleitman • CONTROL • They were NOT told whether they had been woken in REM sleep or in NREM sleep • Woken in BOTH REM and NREM
Dement and Kleitman • FINDINGS of 9 participants • dream reports (DV1) • REM SLEEP • 191 awakenings • 152 dream reports • 39 no dream reports
Dement and Kleitman • FINDINGS of 9 participants • Dream reports (DV1) • NREM sleep • 160 awakenings • 11 dream reports • 149 no dream reports
Dement and Kleitman • FINDINGS of 9 participants • dream reports (DV1) • HIGH incidence of dream recall after REM • LOW incidence of dream recall after NREM
Dement and Kleitman • FINDINGS of 9 participants • Length of dream correlated to length of REM (DV2) • How was this done?? • Ps awakened randomly after 5 or 15 minutes of REM and asked to guess how long theyhad been dreaming • (5 or 15 minutes)
Dement and Kleitman • FINDINGS of 9 participants • 5 minutes REM SLEEP • 45 reports were right • 6 reports were wrong • 15 minutes REM sleep • 47 reports were right • 13 reports were wrong
Dement and Kleitman • FINDINGS of 9 participants • length of dream correlated to length of REM (DV2) • most Ps guessed accurately except one P who could only remember the ends of dreams
Dement and Kleitman • FINDINGS of 9 participants • relationship between the type of eye movement to CONTENT of dream • (DV3) • Ps woken when TYPE of eye movement was regular (vertical etc) • 21 wakings - reports always looking at people or objects near to them
3 out of 35 awakenings were for vertical movements • Standing at the bottom of cliff hoisting things up • Climbing a ladder • Playing basketball
One horizontal awakening Throwing tomatoes
10 little or no eye movement 2 occasions driving car looking into distance then look left at car pulling out or man waving A quick glance left observed just before waking
Dement and Kleitman • SUMMARY & conclusions • regularly occurring REMs every night • Most Ps recalled dreaming in REM • lack of dream recall + light brain waves suggest NO dreaming in NREM • Objective measurement of dreaming MAY be achieved by recording REMS while people sleep
Dement and Kleitman • Evaluation • REM sleep is important • the brain needs to sleep to organise itself • evidence • babies sleep longer than old people • REM is longer after complex tasks
Dement and Kleitman - QUESTIONS • Does it matter that only 2 Ps were female? • Why were Ps asked to refrain from alcohol / caffeine? • Why was it important that the Ps did not know whether they were in REM or NREM? • Does the size of the sample matter?
Dement and Kleitman - QUESTIONS • Why might the sleep patterns be different when the Ps sleep in their own beds? • Why might some of the Ps have recalled dreams when they were woken in NREM • To whom can we generalise the findings? • Was the study ethical?
Dement and Kleitman - QUESTIONS • What was the IV? • What were the three DVs? • What is the MAIN disadvantage of correlational analysis? • Have D & K established that dreaming ONLY occurs in REM sleep?
Dement and Kleitman • YOU MUST read this study up • Also - • try to read a chapter on SLEEP RESEARCH in GROSS or CARDWELL
Dement and Kleitman • Try recalling your own dreams • Keep a dream diary • Do you dream more after you have been studying hard? • The end