(b) dement & kleitman Flashcards
psychology investigated
sleep, dreams, ultradian rhythms
dreams
a sequence of images, emotions, and thoughts passing through a sleeping persons mind
ultradian rhythms
biological rhythms that repeat more frequently than once a day
EOG
electrical recording of eye movement patterns (2 electrodes near the eye)
EEG
monitors electrical activity of the brain associated with nerve and muscle activity
what are the sleep stages
REM and nREM
do you dream in nREM
no
how many stages in nREM
3/4 stages
nREM stage 1
- breathing and heart rate slows
- hypnagogic sensations or hallucinations
- easily awakened
hypnagogic
falling/floating sensations
nREM stage 2
- decrease in breathing, muscle tension, heart rate, body temp
- helps process simple and complex motor skills
- not easily awakened
nREM stage 3/4
- large, slow brain waves — when consistent becomes stage 4
- deep sleep, extremely relaxed
- disoriented & confused upon waking
- growth hormone secreted
- body maintanence and restoration
overall aim
to investigate dreaming in an objective way by looking for the relationship between eye movements in sleep and dreamers recall
how many procedures are there
3, 1. dream recall, 2. dream length and REM length, 3. eye patterns and dream content
3 procedures to test for 3 specific aims
aim 1 (dream recall)
to investigate if dream recall between REM and nREM sleep is different
aim 2 (dream length)
to investigate if dream length estimates and length of REM period correlate posiitvely
aim 3 (dream content)
to investigate if eye movement patterns are related to dream content
sample
- 9 ppts (7M, 3F)
- 5 studied intensely
sampling method
opportunity sample
- all american, from chicago
instructions given to ppts
- report to lab before you would usually go to bed
- avoid caffiene/alcohol
- eat normally
- you will sleep in a dark, quiet room
- you will be woken at random intervals by a doorbell
type of experiment
laboratory experiment
experimental design
repeated measures
procedure 1
- doorbell was positioned near the bed to wake up ppts
- ppts were woken at random intervals (either during REM or nREM)
- ppts spoke into a recording device
- stated if they were dreaming or not
- dream content was recorded
procedure 2
(originally ppts were asked to estimate dream length to the nearest minute, was too hard so –>)
- ppts were woken after 5 or 15 minutes of REM
- asked if they thought they were dreaming for 5 or 15 min
- their answer and dream narrative was recorded
- number of words were also counted
procedure 3
(originally ppts were asked to estimate dream length to the nearest minute, was too hard so –>)
- ppts were woken after their eyes moved in the same way for longer than a minute
- dream content was recorded
results 1
REM –> 152 instances of dream recall, 39 instances of no recall
nREM –> 11 instances of dream recall, 149 instances of no recall
results 2
- 88% accurate responses for 5 min REM
- 78% accurate responses for 15 min REM
results 3
vertical eye movements: climbing a ladder, shooting basketball hoops
horizontal: watching people throw tomatoes at eachother
little/no movement: staring at something, watching the distance
large eye movement to left: a car appeared from the left as they were driving
mixed eye movements: looking at close objects, talking to someone
conclusions 1
dreams mostly occur in REM sleep, any in nREM are usually from the earlier REM period
conclusions 2
dreams are not instant events but are reported/experienced in real time
conclusions 3
REM eye movements during sleep do correspond/are linked with the content of a dream
evaluation strengths
- high level of control
—> lab setting, allows for better control of the IVs (REM/nREM) and potential UVs (eg, caffiene, alcohol)
—> increases confidence in that only the IV is causing the DV - high reliability, replicability, and standardisation
—> eg, same recall procedure used w/ ptps reporting into tape recorder, and doorbell used to wake ppts each time in the same quiet, dark sleep setting
—> ensures consistency between ppts trials - EEG and EOG are objective and quantitative measures of sleep stage
—> easy to analyse statistically and compare differences in dream recall and dream duration estimates between REM and nREM
evaluation weaknesses
- unrepresentative sample
–> mostly males, only living in Chicago
—> could lower generalisability - low ecological validity
—> sleep setting is in a sleep lab, and being woken at random intervals and asked to report on dream content lacks mundane realism
—> results may lack generalisability to people sleeping normally
ethical issues
GOOD
- confidentiality maintained
- no lasting permanent damage is caused by EEG and EOG
- ppts not forced to tell dream narrative
BAD
- ppts were sleeping in unnatural settings and woken through the night
—> this may have affected them the following day
application to daily life
- could be used for treating/checking for sleep disorders
- check if disorder occurs in REM or nREM
- are brain waves atypical?
nature-nurture
nature: REM and nREM are universal and due to nature/our biology
nurture: individual differences could have been due to environmental factor
—> nurture could affect sleeping patterns too
