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