DEMENT & KLEITMAN Flashcards
BACKGROUND
- 1955 study revealed that Ps who were woken from REM were more likely to report vivid dreams
- demonstrated that sleep consisted of several alternating stages
established link between REM sleep and dreaming - laying the foundation for modern sleep science
PSYCH BEING INVESTIGATED
EEG - records freq. of brain waves + electric voltage during sleep - identify REM and nREM = objective and reliable
EOG - record eye movements - attaches electrodes on scalp and near eyes
dreaming is subjective experience of imagery while asleep
REM - when dreams occur
nREM - other stages of sleep - differ in brain activity
AIM
to investigate the relationship between dream content and psychological indicators of dreaming (eye movement)they aimed to find objective methods to demonstrate a relationship between dream content and physiological indicators of dreaming, such as eye movements
does dream recall differ between REM and nREM stages of sleep
is there a positive correlation between subjective estimates of dream duration and the length of the REM period before waking
are eye movement patterns related to dream content
SAMPLE
- 9 adults - 7M, 2F
- five main Ps studied intensely - spent 6 and 17 nights in laboratory
- other four used to confirm results - spent only 1 to 2 nights in lab
- all Ps identified by initials
PROCEDURE
repeated measures design
laboratory experiment
day - P ate normally (excluding caffeine and alcohol) and then went to lab before their bedtimes
all P went to bed in quiet dark room with 2 electrodes attached on scalp (EEG) and beside the eyes (EOG)
EEG wires gathered in a single ponytail to avoid entanglement
EOG ran continuously
P woken by a loud doorbell sound placed near the bed
IV 1 + RESULTS
P woken at either REM or nREM sleep (not told which) - confirmed whether or not they were having a dream - described contents in voice recorder
IV - time of awakenings (REM or nREM)
DV - whether they had a dream or not
DV - report of dream narration content
many more dream recalls in REM (152/191) than nREM (11/160)
P frequently described dreams when woken from REM
nREM - P describe feelings but not specific dream content
when woken in nREM P returned to nREM - when woken in REM they typically didnt dream again until next REM phase
IV 2 + RESULTS
P woken randomly after either 5 or 15 minutes of REM sleep - initially asked to estimate the length to the nearest minute - in revised they were given fixed choice (5 or 15)
no. of words in dream narrative was counted
IV - randomly woken at 5 or 15 minutes
DV - dream duration (they estimated which duration and number of words to measure dream length)
88% (45/51) - correct 5 minutes
78% (47/60) - correct 15 minutes
REM duration and number of words were significantly positively correlated (0.4-0.71)
IV 3 + RESULTS
direction of eye movements detected with EOG - electrodes near eyes
eye movement patterns: vertical, horizontal, both, little or none
P woken after continuous movement of one eye pattern for more than one minute + asked to report dream
IV - eye movement pattern type
DV - dream content
strong correlations between eye movement patterns during REM and ream content - suggests it reflects the dreamer’s gaze in dream - direct link between physiological activity and subjective dream experience
VERTICAL - climbing set of ladders and looking down
HORIZONTAL - watching two people throwing tomatoes at each other
MIXED - fighting with someone close to them
NONE - watching something at a distance
CONCLUSION
dream reported REM not nREM
can judge duration of REM accurately
+ correlation - eye movement and dream content
GRAVE
APP. TO EVERYDAY LIFE
Understanding typical patterns of sleep and dreaming is important:
Psychologists can identify people whose sleep and dreams are unusual. People are more likely to receive suitable treatment/support to improve sleep quality.
NATURE VS NURTURE
biological explanation for dreaming, emphasize role of natural physiological processes - but doesn’t exclude possibility that dream content may be influenced by learned/cultural factors
Support for nature: all participants demonstrated ultradian REM/NREM sleep cycles and dreamed more during REM than NREM. This suggests these patterns are innate and may help us to survive.
Support for nurture: dream content was diverse; differing life experiences affect what we dream about and may affect the duration of REM sleep.
INDIVIDUAL VS SITUATIONAL
ETHICS
