Dement & Kleitman (1957)

1. Therelation of eyemovementsduringsleeptodreamactivity: Anobjectivemethodforthestudy of dreaming. Dement & Kleitman (1957)

2. SLEEP • It is an interesting topic and it has been usually studied by medicine. • The better way to investigate this issue, is using electroencephalography (EEG) measuring brain activity during sleep. • This usually gives an idea of the “structure” of sleep during the night.

3. SLEEP • NREM SLEEP (9-130 mins) • Each stage • STAGE 1: (hypnagogic stage) • Transition state between being awake and sleeping. • Eyes move more slowly • Muscle activity and heart rate slow down. • Light sleep where you can be awakened easily • Relaxation stage drowsiness • STAGE 2: • Movement stops • Brain waves become slower with an occasional burst of rapid brain waves. • At this point, the body prepares to enter deep sleep.

4. SLEEP STAGE 3- Extremely slow brain waves (delta waves) -Combined with smaller, faster waves called theta waves. STAGE 4- Deepest sleep. - No eye movement or muscle activity - Brain produces more delta waves than theta waves. - In Stage 4, some may experience sleepwalking or night terrors.

5. REM SLEEP (rapid eye movement) STAGE 5- Breathing becomes more rapid- Eyes move rapidly - Muscles are temporarily paralysed. (to protect from acting out)  Heartbeat may increase and muscles may experience occasional muscular twitches. - REM usually takes place 90 minutes after falling asleep. • Normal sleep cycle: Stages 1, 2, 3, 4, 3, 2, REM

7. BACKGROUND AND CONTEXT • Dreaming and sleep are closelyrelated, butonlyrecentlyit’sbeenstudiedscientifically. • Itis a veryinterestingtopic, and has caughttheattention of manyscientists. • Sleepdeprivation one of theways of studyingsleep.

8. BACKGROUND AND CONTEXT • Scientificstudy of dreams physiological variables using a reliablescientificmethodto determine exactlywhendreamingoccurs. • Selfreport thereis no otherway of provingdreamingoccured. • Selfreports + physiologicaltechniquestomeasurephenomena reliable and objective

9. BACKGROUND AND CONTEXT • Aserinsky + Kleitman firsttostudyrelationshipbetween REM and sleep • Theydiscoveredthathighdreamrecall in participantswoken up during REM. • Theyconfirmedtherelationshipbetween REM + SLEEP + DREAMING

10. BACKGROUND AND CONTEXT • Theyalsodiscoveredthattherewas a cyclicprocess depth of sleepchangedduringthenight

11. AIM AND NATURE • Thisstudy shows theresults of a rigoroustesting of therelationshipbetweeneyemovement and dreaming. • Hypotheses: • Thereis a significantrelationshipbetween REM/NREM sleep and dreaming, suchthat (basedonpreviousresearch). REM sleepisassociatedwithdreaming and NREM, isn’t.

12. AIM AND NATURE • 2. Thereis a significant positive correlationbetweenthesubjectiveestimate of theduration of dreams, and thelength of eyemovementperiod prior toawakening. • 3. Thereis a significantassociationbetweenthepattern of eyemovement and thecontent of thedream. Eyemovementreflectsthe visual experience of thedream.

13. METHOD / DESIGN • 7 adult males / 2 adultfemales • Studiedundercontrolledlabconditions • 1 night in thesleeplabbeingwoken at variousintervals • Physiologicalrecordingsweremade of: • Changes in corneoretinalpotentialfields as theeyes moved • Brainwaves (as a criterion of depth of sleep)

14. METHOD / DESIGN • Twoor more electrodeswereattachedneartheeyes • Twoorthreeattachedtothescalp. • Participantswerewokenbytheringing a doorbell nearthebedforthemtowake up.

15. METHOD / DESIGN • Participantshadtospeakinto a recordingdevicenearthebed and say: • Whetherornottheyhaddreamt • Iftheycould, relate thecontent of thedream • No communicationbetweenparticipants and theexperimenteruntilithadbeenjudgedthattheparticipanthadbeendreaming.

16. Howdidtheyknowparticipantshadreallydreamt? • Theyhadtogive a coherent, fairlydetaileddescription of dreamcontent. • Onlythentheexperimentercouldentertheroom and askfordetails. • Participantsdidn’tknowiftheywerewokenfrom a REM or NREM sleep.

17. RESULTS/ FINDINGS • REM sleepbasicallyhadlowvoltagerelativelyfast EEG pattern.

18. RESULTS/ FINDINGS • In between REM periods EEG indicated deeper sleep • They were either • High voltage • Slow activity • Or frequent No REMs were observed during the initial moments of sleep

19. RESULTS/ FINDINGS • REM uninterrupted periods lasted between 3-50 minutes (mean 20) • They tended to increase the later in the night they occurred • The eyes didn’t move with a constant pattern they occurred in bursts of 1, 2 to 100 movements • A single movement lasted 0.1-0.2 seconds and followed by a fixation pause of varying duration.

20. RESULTS/ FINDINGS • The REM periods occurred quite frequently during the night average every 92 minutes. • Awakenings during the night: Despite the awakenings, sleep was similar to uninterrupted sleep.

21. RESULTS/ FINDINGS HYPOTHESIS 1 • Participants uniformly showed a high incidence of dream recall following REM awakenings, and a low incidence following NREM awakenings. • When REMs stopped, the incidence of dream recall dropped dramatically. • Within 8 mins after REM ended in 17 awakenings  5 dreams were recalled • Within more than 8 mins after NREM 132 awakenings 6 dreams were recalled.

22. RESULTS/ FINDINGS • Participants were more confident they hadn’t dreamed, after NREM • When aroused during deep sleep they were confused and they felt they must’ve been dreaming but they didn’t remember the dream. • When participants couldn’t recall a dream following REM sleep, this was usually in the first two hours.

23. RESULTS/ FINDINGS • HYPOTHESIS 2 Participants were woken after 5 or 15 mins after REM, and based on their recall of the dream, they had to decide which was the correct duration. • All but one could do this accurately • Significant correlation between minutes of REM and lengths of dream narratives (words)

24. RESULTS/ FINDINGS • HYPOTHESIS 3 it was hard to know the direction in which Ps were looking when dreaming. • They were woken up as soon as a pattern of eye movement persisted for at least a minute. • Mainly vertical • Mainly horizontal • Vertical and horizontal • Very little or no movement.

25. RESULTS/ FINDINGS • Of 35 awakenings only 3 periods of only vertical oronly horizontal. • Therewereseveraldreams and usuallyeyemovement corresponded towhatwas happening in thedream. • In participantswithmixedmovements usuallytheywerelooking at a movingobjectclosetothem.

26. CONCLUSIONS • Each of the 9 participantshadregularly REM periodsduringthenight. • As predicted: 1. Highincidence of dreamrecallocurredwhenparticipantswerewoken up after REM. Lowfor NREM. 2. When a series of awakeningsocurredeither 5 or 15 minutes afterREMshadbegan, participantsjudgedthecorrectdreamdurationveryaccurately. 3. Thepattern of REMswasrelatedtothe visual imagery of thedreams. RecordingREMsduringsleep objectivemeasure of dreaming.

27. EVALUATION: Methodologicalissues • Beaumont being woken from NREM dream may lead to forgetting more than with REM • In REM sleep the brain is more active • This could be a major confounding variable that could make all these results to be questionable easily.

28. Herman thereis no considerable difference in dreamreportbetween REM and NREM. • Foulkes: sayingthat REM=dreamingand NREM = non dreaming oversimplification • Although only 5-10% of NREM sleepers reported dreaming, 70% could report dream like impressions. • Besides, dreaming is also established to occur during the hypnagogic period and daydreaming.

29. Theoreticalissues • Oneofthegreatquestionsofpsychologyis “isdreaminguseful?/necessary?” • Shouldsleep be seen as active orpassive? • Sleepisan active process not a consequence of neuronal fatigue. • The brain of a sleeping person is almost as active as the one from a person who’s awake. • SLEEP IS AN ACTIVE PROCESS

30. Theoreticalissues • Evidence has beenbeenfoundfortherelationshipbetween REM sleepanddreamingrem rebound phenomenon. • REM rebound: When people are deprived from REM sleep, the next night they “make up” for it. Compensation. • Dement: when participants were deprived from REM sleep irritable, nervous, unable to concentrate, paranoid, hallucinations, etc. • These symptoms were very possibly, consequence of Dement’s own expectations he told the Ps that this experiment could have consequences and had an available psychiatrist.

31. Theoreticalissues • Dementreplicatedthestudyandfound no evidenceforpsychiatricimpairment in REM deprivedPs. • He alsofoundevidenceforthe REM rebound • Then, possibly REM anddreaming are themostimportantfunctionsofsleep.

32. Subsequentresearch • 1990’s There was a change in the vision of dreaming and REM. • Dreaming appeared to be a continuous process that also occurred during NREM periods. • NREM dreams shorter and more rationally constructed. • REM dreams more emotional and more detailed.

33. Subsequentresearch • Researchersquestionedifreally REM wasnecessaryfordreamingtotake place • At somepoint, REM sleepwaslinkedto a brainstructurecalled PONS (researchwithkittens)

34. Subsequentresearch • But, evidence: peoplewithproblems in PONS dreamtanyway. • Orpeoplewhosaidtheyhadneverdreamed, buthadanintactpons, even thoughtheywentthrough REM phases. • Buttheyhadlesions in otherbrainstructures. Whatisclearforthisresearch Dreamtakes place independently of REM and thepons.

35. Subsequentresearch Hobson’sActivation-Synthesismodel: “REM-ON” arealocated in thepontine reticular formation ACTIVATION REM sleep • Thispreventsmostsensoryinformationfromreachingthebrain. • Theswitchfromthemotor cortexisswitched off, causingthepersontobeparalysedduring REM sleep. • Otherstructuresassociatedtomemory and emotion are activated

36. In summary • When REM sleepoccurs: • REM-ON area: Activation (ON) • Motor cortex OFF • Memory and emotionstructures ON (probablyhippocampus and amygdala)

37. Subsequentresearch • Dreamingoccurswhenthesesystemsactivatesimultaneously and are syntethized similar to a wakingbrain • In a wakingbrain + + + + SENSORY INFORMATION MOTOR INFORMATION EMOTIONAL INFORMATION MEMORY Thisinformationispresented in anorderedwaywhenwe are awake SENSE OF REALITY

38. Subsequentresearch • In dreamsinformationdoesn’tfollow a logicorder weirddreams • Theinternalprocessesinvolved in dreaming are random. • Dreamsnormallyinvolvesactivityfromthe visual and motor systems. • Manydreamscouldbeunderstoodbasedonbodyexperience eroticdreams, flying, etc, relatedtocertainorgans.

39. Subsequentresearch • Reverse learning(Crick&Mitchison) wedream in ordertoforget. • A complexassociationalnetworkoverloaded of incominginformation creation of false thoughts. • Thesethoughtsmightbeoutdatedbutpersistent. • REM sleepcouldbeerasingthosethoughts (unlearning)

40. Subsequentresearch • Crick & Mitchison tryingto record ourdreamsisn’t a good idea. They are ideas we’retryingtogetrid of! • Thismodelonlyappliestobizarredreamcontent. And whataboutnarrative? • Thisisbetterunderstood as dreamingto reduce fantasyorobsession.

41. Subsequentresearch • Theactivation-synthesismodelreferstothewherebutnottothewhyorwhatfor. • Hereiswherepsychological (psychodynamic) perspectives come intoplay Freud

42. Freud’stheory of dreams • 1900 Theinterpretation of dreams (S.Freud) • “Todo sueño es cumplimiento de deseo”. • Dreamusuallymanifestcertain ideas orexperiencesthatweren’telaboratedduringtheday (restos diurnos) • 2 types of content: • Manifestcontent: thestoryornarrationitself • Latentcontent: themeaning (underlying)

43. Applications and implications • In animals, REM sleepmayhaveevolvedtoaccessrepeatedlytheinformationusefulforsurvival (location of food, etc) • Tomantainsleep movementhadtobesuppressed (motor neurons) otherwiseyouwake up! • Eyemovementwasn’tenoughttowake up, so thereisstillaccessto visual informationthat, combinedwithpastexperience strategyforbehaviour. • Itmightbeadaptive

44. Applications and implications • In humans… • Itcouldbethatthe crucial informationforsurvivalisthebasicinformation in theunconscious. • Wehavelanguage, animalsdon’t. Informationisbasically visual weinheritedit? • Butthisinformationforus, couldbeuseful. That’swhywerememberdreams. • Wedream more under stress relatedtodifficulties. They are EMOTIONAL.

45. Applications and implications • Usually in mooddisorders, there are alterations of sleep. • Babieshave more REM sleep thissuggeststhatmaybeone of thefunctions of brainactivationisthedeveloping of thebrainitself.