dement and klietman 1957 Flashcards
what approach is the study by Dement and Kleitman
its under the biological approach
what is the psychology being investigated in the study by Dement and Kleitman
Our body follows two types of sleep: REM (rapid eye movement) sleep and nREM (non-rapid eye movement) sleep.
nREM can be divided into 4 sleep stages.
In REM sleep, our eyes move rapidly under the lids.
REM sleep resembles wakefulness as our eyes move; we often experience vivid (bizarre) thoughts in dreams, and our brains are active. However, it is different from wakefulness as it is difficult to wake up; we are relatively insensitive to stimuli and paralyzed
nREM sleep are the other stages of sleep and they differ in brain activity
what is the background in the study by Dement and Kleitman
Aserinsky and Kleitman (1955) study observed periods of rapid, conjugate eye movements during sleep and found a high rate of dream recall in awakening participants during REM sleep and a low rate when awakened at other times.
Sleep and dreaming are hard to investigate because the participant is necessarily asleep, and so cannot communicate with the researcher. Even when awake, only self-report data can be obtained about dream content, which alone may be invalid as it is subjective.
EEG- monitors the electrical activity of the brain.
EOG - allowed the electrical recording of eye movement patterns
what were the aims of the study by Demenet …
1)To investigate if dream recall differs between REM and NREM stages of sleep
2)To investigate if there is a positive correlation between estimated dream duration and REM period length
3)To investigate if there is a correlation between eye movement patterns and dream content
what were the hypothesis in the study by Dement and Kleitman
1) there will be a significant association between REM sleep and dreaming
2)There will be a positive correlation between estimated dream duration and REM sleep
3)There will be a significant association between eye movement patterns and dream content
What is the research method in the study by Dement and Kleitman
laboratory experiment
Explain approach 1
state the type of experiment , research design and iv/dv in the study by Dement and Kleitman
- natural experiment
- repeated measures design
- IV : whether the participants woke up from REM or NREM stages of sleep
-Dv : whether the participants recalled a dream or not
Explain approach 2
State the; type of experiment , research design , iv and dv in the study by Dement and Kleitman
- true experiment using a correlational study
-Repeated measures design
-IV ; waking up participants after 5 or 15 minutes of REM sleep
-DV ; participants guess on dream duration (either 5 or 15 min)
Explain approach 3
State the; type of experiment , research design , IV and DV in the study by Dement and Kleitman
- Natural experiment
-Repeated measures design
-IV; eye movement patterns
-DV; dream content
What is NREM and REM in the study by Dement and Kleitman
Non rapid eye movement and rapid eye movement
Describe the sample in the study by Dement and Kleitman
- The sample consisted of 7 male adults and 2 female adults , 5 of which were studied in detail and 4 were used to confirm the results of the first 5
- The 5 main participants spent about 6-17 nights in the lab
-They were woken up approximately 50-77 times
-The other 4 participants spent only one or two nights in the lab with 4-10 awakenings.
-Participants were identified by their initials to maintain confidentiality
Describe the procedure in the study by Dement and Kleitman
-Participants reported to the lab a little before their usual bedtime
- They were told to eat normally but to abstain from alcoholic or caffeine containing drinks the day of the experiment.
-They slept in a dark, quiet room. They had 2 EOG electrodes near their eye and 2/3 EEG electrodes to the scalp. A doorbell (for standardisation) that was loud enough to rouse them from any sleep stage , was used to wake participants up at random from REM or NREM
-The doorbell rang at various times during the night and the participants indicated whether they had been dreaming or not and described their dreams in a voice recorder
Describe the procedure for hypothesis/aim 1 in the study by Dement and Kleitman
The participants were woken up from either NREM or REM stages of sleep , but they were not told which
-The choice of awakening was decided in different ways for different participants :
a)Participants PM and KC = using a random number table
b) Participant DN = in groups of 3 REM then 3 NREM
c) Participant WD = by telling the participant that they would only be woken up in REM but actually waking them up in REM or NREM
d) Participant IR = in no specific order the experimenter just choose
– after being woken up the participants stated whether they were having a dream or not if so they described the content of the dream into a recorder
–When the participant finished the experimenter occasionally entered the room to ask further questions about the dream
How were participants PM and KC woken up in the study by D and K
Using a random number table
How was participant DN woken up in the study by D and K
in groups of 3 REM and 3 nREM
How was participant WD woken up in the study by D and K
by telling the participant that they would only be woken up in REM but actually waking them up in REM or NREM
How was participant IR woken up in the study by Dement and Kleitman
in no specific order the experimenter just choos
Describe the procedure for hypothesis/aim 2 in the study by Dement and Kleitman
Participants were woken following 5 or 15 minutes of REM sleep
They were asked if they thought they had been dreaming for 5 or 15 minutes
Their dream narrative was recorded and the number of words was counted
Describe the procedure for hypothesis/aim 3 in the study by Dement and Kleitman
-Participants were woken up after exhibiting a single eye-movement pattern for longer than a minute
- The direction of eye movement was detected using EEG electrodes around the eyes.
-The eye movement patterns detected were; ‘mainly vertical’ , ‘mainly horizontal’ , ‘both vertical and horizontal’ , ‘very little or no movement’.
- The dream content was recorded
In which stage of sleep did participants recall most of their dreams in the study by Dement and Kleitman
REM sleep
Describe the general results in the study by Dement and Kleitman
Describe the results for hypothesis 1 in the study by Dement and Kleitman
Participnats frequently described dreams when woken from REM but rarely did so when woken from nREM
-Participants were able to recall a dream from 152/191 awakenings from REM where as from 149/160 awakenings from nREM they did not recall a dream
Describe the results for hypothesis 2 in the study by Dement and Kleitman
- Participants had an 88% accuracy in estimating they were woken up after 5 minutes of dreaming.
-Participants had a 78% accuracy in estimating that they were woken up after 15 minutes of dreaming.
-Dn made the most of these incorrect choices.They estimated 15 minutes to 5 minutes. The dream was long but DN was only able to remember the latter part
Describe the results for hypothesis 3 in the study by Dement and Kleitman
**Eye movement patterns as recorded on the EEG were related to dreams visual content.
Mainly vertical eye movement results
- One dreamer was throwing a basketball at a net , shooting looking up at the net then down to pick another ball
Mainly horizontal eye movement results:
-There was only one instance of mainly horizontal eye movement patterns; the dreamer reported he was watching two people throwing tomatoes at each other
Mixed eye movement results:
-21 awakenings had mixed eye movement patterns subjects reported looking at objects or people close to them. For example talking to a group of people , looking for something or fighting with someone
results for little to no eye movement patterns;
- 10 dreamers had little to no eye movement patterns
the dreamer reported watching smth at a distance or staring at an object
-subjects were woken up when no eye movement was followed by a sudden burst of activity to the left e.g
1)one dreamer reported that he was driving a car staring at the road ahead. As he approached a junction he was startled by a speeding car to the left.
