2.1 Dement and Kleitman (sleep and dreams) Flashcards
Aim
Does dream recall differ between REM and quiescent nREM stages of sleep?
Is there a positive correlation (link) between subjective estimates of dream duration and length of REM before waking?
Are eye-movement patterns related to dream content?
If there is a positive correlation between the length of REM and the number of words given in a dream narrative.
Research method and design
Used several methods in a laboratory setting (experiment and correlation ) with a repeated measures design.
IV and DV /Co-variables for each aim
Aim 1-
IV- whether woken in REM or nREM stage of sleep
DV- could recall dream content
Aim 2-
Co-variable 1- woken 5 or 15 minutes during the REM stage of sleep
Co-variable 2- perception of the dream length being 5 or 15 minutes.
Aim 3-
IV- eye movement pattern before waking :
horizontal, vertical, horizontal and vertical, little to no movement
DV- description of the dream
Aim 4-
Co-variable 1- number of minutes spent in REM sleep
Co-variable 2- number of words in the corresponding dream narrative recording
Sample and sampling technique
Seven male and two female adults
5 studied in great detail, 4 for confirming results of the five
sleep laboratory a t university of Chicago, USA
opportunity sampling technique ( information from google)
EEG full form
electroencephalograph
For aim1 what was the order of waking in REM or nREM for the 5 participants?
PM and KC- used a random number table
DN- groups of three REM and then three nREM
WD- told the participant they would only be woken in REM but actually woken in either REM or nREM
IR- no specific order, the experimenter just chose
Findings about uninterrupted dream stages
lasted 3-50 minutes (mean 20 minutes)
were typically longer later in the night
intermittent bursts of around 2-100 rapid eye movements
Length of a sleep cycle
70 to 104 minutes with a mean of 92 minutes
Procedure for each of the aims
pg.76 Cambridge
results for aim 1
able to recall dreams from 152/191 awakenings in REM, 79.6%
149/160 awakenings in nREM not able to recall dreams, 93.1%
results for aim 2
accuracy for estimating 5 minutes- 88%
accuracy for estimating 15 minutes- 78%
results for aim 3 (description of dream in relation to each eye movement)
(3)vertical eye movement- climbing up a series of leaders looking up and down, standing at the bottom of a cliff operating a hoist, throwing basketballs at a net
(1)horizontal eye movement- watching two people throw tomatoes at each other
(10)little to no eye movement- watching something in a distance or looking at an object
two instances when there were several eye movements to the left just before waking.
1) driving a car, then approached a road junction and was startled by a speed car appearing at his left
2)driving a car and immediately before being awakened he saw a man standing to the left of the road and acknowledged him
(21) Mixed eye movement- looking at objects or people close to them
results for aim 4
r=0.4 to r=0.71
methodological strengths
high level of standardisation- reliable. used a loud doorbell, fitted with the same equipment, all in a quiet and dark room
laboratory experiment- control over variables
avoided investigators effect- no one was present when the participants recalled their dreams
quantitative data- objective, use of scientific equipment
methodological weakness
individual differences- for aim 4 some participants could have been more verbal hence the dream narrative longer
sample too small- not generalisable
lacks ecological validity- sleeping in a lab with electrodes attached, not in their natural environment, refraining from alcohol and coffee
