Sleep & Dreaming - Dement & Kleitman PDF

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Description on Dement & Kleitman study on Sleep and dreaming...

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STAGES OF SLEEP :

*REM : Rapid Eyes Movement ● -

Stage 1 Beginning of sleep / light sleep Transition between wakefulness & sleep Lasts 5 - 10 minutes

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Stage 2 Lasts about 20 minutes Produces bursts of rapid, rhythmic brain activities called sleep spindles (short burst of brain activity) Body temp reduces & heart rate slows

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Stage 3 & 4 - delta waves for healing / recover Deep, slow brain waves known as delta waves emerge Become less responsive to the environment Transition between light sleep & very deep sleep Lasts about 30 minutes REM

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Characterized by eye movement, increased respiration & brain activity The brain & body systems seem to be more active, but the muscles become relaxed Dreaming occurs here Lasts about ½ hour to an hour

BACKGROUND : ● The occurrence of eye movement in relation to dreaming was confirmed in normal subjects & schizophrenics as well ● It appears at regular intervals in relation to cyclic changes in depth of sleep as measured by an EEG CATEGORIZED OF SLEEP : 1. NREM sleep (stage 1-3) 2. REM sleep AIM: 1. 2. 3. 4.

To test relationship between the REM and dreaming To see if the participants accurately estimate how long they’ve been dreaming To see if eye movement (direction) during REM correlates with dream content To see whether or not the length of REM matches the number of words subjects used to describe the dream

IV : 1. Stage of sleep ● Levels : NREM ● Levels : REM 2. ● ● ●

Time of awakening After 5 mins (into REM) After 15 mins (into REM) Asked them how long they’ve been dreaming (5 or 15 mins) =

3. ● ● ● ●

Direction of eye movement Vertical Horizontal Mixture No movement [REM because based on brain wave potentials]

4. Number of words

DV :

1. 2. 3. 4.

Number of dreams recalled Number of correct dream length Subjective report of dreaming Length of dream

NO HYPOTHESIS SUBJECTS : ➔ 7 adult males, 2 females = 9 subjects ➔ 5 were studied intensively while data was gathered ➔ 4 were minimal with intent of confirming results of first 5 ➔ Self selecting sample ➔ 2 sleep for one night, 2 sleep for 2 nights, 5 sleep for many nights PROCEDURE : 1. Came before bedtime 2. Instructed to eat normally & avoid; - Alcohol - Coffee - Nicotine 3. 2 or more electrodes attached near eyes to register corneoretinal potential field 4. 2-3 attached to scalp for recording brain waves 5. EEG ran continuously throughout the night at a paper speed of 3 - 6mm per second 6. Facter speed was used for detailed examination of brain waves (3cm/s) 7. Slower speed gave an approximate of gross pattern 8. At various times during the night, subjects were awakened to test dream recall 9. Return to sleep took less than 5 minutes Hour of awakening

Percentage of awakenings

First 2 hours

21

4 hours after initially sleeping

29

6 hours after initially sleeping

28

8 hours after initially sleeping

22

CONTROL : ● No alcohol, coffee & nicotine ● If you woke up seeing someone’s face, it could influence / affect the memory of your dream - the researchers can’t be there to wake them up (use alarm, loud bell,

microphone) = there’s no chance of unintentional RESULTS : For 1st AIM: ● Eye movement periods & dream recall 1. Subjects PM and KC : - (no possibility of biased - pure random) - Awakenings chosen according to a table of random numbers to eliminate possibility of patterns 2. Subjects DN : - First 3 awakenings must happened during REM - No : they don’t show any 3. Subjects WD : - Told he would only be awakened when dreaming, but actually randomly awakened - Random but told to be awakened 4. Subjects IR : - Awakenings chosen according to the researcher ● REM happens at least for 1 period [range of REM periods : 3 - 50 minutes] ● When the researcher awakened the subjects during REM, but the subjects said they’re not dreaming / can’t speak about it in details = counted as not dreaming ● Don’t have average, because they can’t find enough ● Extraneous variable : the researcher waking the subjects ● Average number of subjects to fall into REM - 92 minutes (70 - 104 mins) REM Dream recall

No recall

Dream recall

No recall

152

39

11

149

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NREM

No differences found in REM awakening in first ½ vs last ½ Incidences of dream recall after REM dropped significantly They might have a bit of previous REM dream recall in NREM (because are awaken much closer to REM period) - waking up 7 times of 8 minutes & Ss recall dream for 5 times When aroused during deep sleep, subjects awoke bewildered & were sure they were dreaming This is though they couldn’t remember the dream. Otherwise they thought they weren’t asleep at all Subjects felt a variety of feelings (pleasantness, anxiety, detachment) but couldn’t relate it to a dream

For 2nd AIM : (no specific aim) Length of REM & subjective dream duration estimate - Subjects were then asked to choose whether they’ve been dreaming for 15 or 5 mins - All subjects were able to choose the correct dream length with high accuracy except DN

● A. B. C. D. A. B. C. D. A. B. -

Specific eye movement patterns & visual imagery of dreams PURE VERTICAL MOVEMENT 3 were seen Subjects dreamed of standing at the bottom of a tall cliff operating a hoist The subject were looking at various levels of up & down at the machine Another dreamed of climbing a series of ladders He looked up and down as he climbed Dreamed of throwing basketballs at a net First shooting, & looking up at the net, then looking down to pick another ball off the floor Only one instance observed Subject watched 2 people throwing tomatoes at each other NO MOVEMENT 10 occasions were seen All had the common property of watching something at a distance 2 showed eerie similarity About a minute of ocular inactivity followed several large movements to the left 1 or 2 seconds before awakening Driving In one instance, subject was driving, staring at the road ahead. He approach a intersection and was startled by a speeding car from the left Driving In the other, the dreamer was driving & staring ahead, and saw a main hail him as he drove past MIXED MOVEMENT 21 instances observed Typical reports were of them talking to a group of people, looking for something / fighting with someone 20 naive subjects (know no aim) & 5 experimental subjects were asked to observe distant & close activity while awake Eye movement potential were all comparable in amplitude & pattern

DATA COLLECTION METHOD : ● Controlled observation [EEG used for brain waves] ● Self report [subjects describe their dreams, tc]

TYPE OF DATA COLLECTED : ● Qualitative

For 3rd AIM: Length of dream narrative & REM - Of 152 dreams recalled, 26 were not included ; poor recording - Dream narratives recalled after 30 - 50 minutes of REM were not much more than if

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recalled after 15 minutes As you describe your dream, the longer you talk, you forgot to describe every single details of your dream (they might skip the important stuff)

DISCUSSION : ● While dreams predominantly were seen in REM sleep, there were still instances of dream recall in NREM (8 minutes) ● RAMSEY : - Dreams could be recalled at any part of the night - Reports were harder to find earlier in the night ● No reports of REM sleep : certain studies reported that some subjects had no REM sleep ● Two (+1) reasons : - Recording was done by sampling [only check on EEG at selected time] - Lower amplification of REM potentials [if electrical potential isn’t strong, won’t showed on EEG / EEG wouldn’t be able to detect the electrical potential] - No eye movement [not use EEG & just see the movements ; no so no REM for em] SUMMARY : ● No indication of dreams happening instantaneously or rapidly ● REM length = DREAM length WHAT MAKES THE STUDY MORE VALID : STRENGTHS 1. Low extraneous variable 2. Naive subjects used to confirm findings

WEAKNESSES 1. Small sample size 2. Low ecological validity

POSSIBLE APPLICABILITY : - Psychodynamic model : therapy (treatment method : to find out when they’re dreaming or having hard time to remember & what time to wake them up)...