(Sleeping & Dreaming) AICE AS Level Psychology Dement & Kleitman (1957) (Sleeping & Dreaming) AICE AS Level Psychology

Background on Sleep Before the study took place, a connection between REM (rapid eye movement) sleep and dreaming was commonplace based on SUBJECTIVE data Physiological approach to dreaming is that dreams are random firings of neurons that we put meaning to Very different than Freud’s idea that dreams are our unconscious thoughts & urges coming to light http://www.youtube.com/watch?v=GidiLjnbNGc

Measuring Sleep During a typical night, a sleeper passes through different levels of sleep in a cyclic fashion every 90 minutes Main ways of Measuring Sleep EEG- measures gross brain wave activity EMG- Measures electrical activity of muscles EOG- measures eye movement

Stages of Sleep Awake (before drifting off) -measured by EEG (typically beta waves) -but when relaxed, brain waves slow, become more regular, and have greater amplitude (now alpha waves) Asleep Level 1 and 2 -light sleep characterized by irregular EEG patterns. -drifting off to sleep, the brain slows further & yields greater wave frequency & amplitude (theta waves)

Stages of Sleep Asleep Level 3 and 4 -Deeper levels of sleep characterized by delta waves (slowest w/highest amplitude) -Level 4 considered ‘deep sleep’ -More difficult to wake someone, but will respond to significant noises (alarm, baby crying, etc.)

Stages of Sleep Sleep cycle goes from 1-2-3-4… 3-2-REM… 2, 3, 4… 3-2- REM roughly every 90 minutes After Stage 4, the sleeper goes back down the ‘sleep staircase’ to Stage 2 and there is a period of REM sleep lasting 15 to 20 minutes (replaces Stage 1). These sleep states alternate during the night starting with a rapid descent into deep sleep, followed by progressively increased episodes of lighter sleep and REM sleep

Stages of Sleep (Staircase)

“It’s the End of the World As We Know it… And I feel Fine”- REM Sleep Named for darting eye movements that are visible to the naked eye and measured through a EOG Characteristics: -fast, irregular EEG activity similar to awake state -temporary paralysis (lack of muscle tone) -through the night, REM episodes INCREASE and delta sleep decreases (eventually to none) -pons plays a role in sleep- sends signals to visual system (thalamus & cerebral cortex) and to spinal cord

Background to Study In 1955, Aserinksy & Kleitman concluded that there was more dream activity in REM then NREM sleep Problem was data was based largely on subject recall that was error-filled from forgetting, falsifying, or demand characteristics Stemming from this, Dement (his student) & Kleitman theorized that, through an EEG, one can OBJECTIVELY measure whether someone was dreaming or not by investigating whether REM sleep significantly correlated with dreaming

Aim of the Study Overall, aim was to see if the physiological aspects of REM sleep related to the subjects’ experiences of dreaming Also, D&K wanted to observe and record the length, frequency, and patterns of Ps REM sleep

Hypotheses H1- There will be a significant association b/w REM sleep and dreaming (would help establish that measuring REM is objective) H2- There is a significant positive correlation b/w the estimate of time spent dreaming and the measurement of REM sleep H3- There is a relationship b/w the pattern of eye movement and reported content of the dream

Methodology- Design & Participants ‘Natural’ lab experiment in a lab setting carried out at the U of Chicago (no mention of recruitment) IV= awoken in REM or NREM sleep, DV= self-report of dreams Participants 7M & 2F (5 intensely investigated for 6-17 nights & 4 to confirm findings for 1-2 nights) Ps instructed to avoid alcohol & caffeine (used as control), but were told to eat normally Ps reported to lab just before regular bedtime (slept in quiet & dark room)

Methodology- Data Collection H1- Quantitative- measured EEG patterns in REM & NREM sleep as reported by Ps recall H2- Quantitative- EEG patterns in REM sleep and Ps estimated time of dreaming compared for correlational data H3- Qualitative- data on dream content compared to observations on the movement of Ps eyes

Methodology- Materials Sleep lab @ University of Chicago EEG machine to measure sleep objectively Electrodes were gathered at the top of Ps head into a single cord Doorbell used to wake up Ps Tape recorder used to record Ps recollections of what they were dreaming about

Procedure- Testing H1 At various times during the night (both during REM and N-REM sleep), Ps were awakened to test their dream recall (random assignment in some sense) The Ps were woken up by a loud doorbell ringing close to their bed. The participant then had to speak into a tape recorder near the bed. They were instructed to first state whether or not they had been dreaming and then, if they could, to report the content of the dream The Ps were only recorded as having dreamed if they were able to relate a coherent and relatively detailed description of the dream content

Procedure- Testing H2 The Ps were awoken (via the bell) at random or specific times by D&K at either 5 mins or 15 mins into a REM period Then asked to say into the recorder (a) if they were dreaming (b) if so, a description of the dream (if possible) (c) An estimation of if they were dreaming for 5 or 15 mins Es usually listened outside the room but sometimes further questioned the Ps inside the room

Procedure- Testing H3 The Ps were woken up one minute after 1 of 4 patterns of eye movement occurred -a-mainly vertical -c-both vertical & horizontal b-mainly horizontal -d-little/no eye movement The Ps were to tell what they were dreaming about D&K then analyzed data to detail patterns b/w the eye movement Totals= 351 awakenings over 61 nights (5.7/P) 21% in first 2 hrs, 29% in 3-4 hrs, 28% in 5-6 hrs, 22% in 7-8 hr

“Losing My ReligioN” Results for REM sleep REM never occurred at the start of the sleep cycle All the Ps showed periods of REM, characterized by a low voltage, relatively fast pattern EEG The avg. occurrence of REM sleep was once every 92 minutes, with range of group b/w 70-104 minutes REM lasted b/w 3- 50 mins, and increased in time as night progressed (avg REM was 20 mins) Eye movement had bursts b/w 2-100 If P was awoken during REM in the final hours of sleep, P often went back to REM sleep, like the brain activity did not finish

Results for H1 *dreaming was deemed to have occurred if the subject could give a relatively coherent & detailed description of the dream More dreams were reported in REM than NREM sleep (shown in both EEG and Ps recall) (see Table 1) When Ps were awoken closer to REM sleep(Within 8 mins), they displayed better recall of dreams When Ps were awoken in deep NREM sleep, they were bewildered & said that they were dreaming but couldn’t describe the content Dream recall increased through the night

Results for H1 Results show that REM sleep is predominantly Table 1- instances of dream recall after REM & NREM Results show that REM sleep is predominantly associated with dreaming, and NREM sleep is associated with periods of non-dreaming sleep

Results for H2 results revealed that all but one of the participants were able to choose the correct dream duration fairly accurately participant (DN) could only recall the latter part of the dream and so underestimated its length (refer to Table 2) Correlations were found to be significant, ranging from .40 to .71 for each participants Findings show that we dream relatively in real time

Results for H2 Table 2- Results of dream duration estimates after 5/15 mins

Results for H3 Findings suggests that the eye movements of subjects are related to the dream content Indicates that the eyes were moving as if seeing what the P was dreaming about Examples: Vertical- looking down a cliff or up a ladder and shooting basketballs horizontal- throwing tomatoes at each other H&V- interacting with and/or looking at close objects no movement- associated with distance objects or stationary ones

Discussion ALL THREE HYPOTHESES CONFIRMED Results obtained by waking subjects strongly support the correlation b/w REM sleep and dreaming Cannot definitively say that dreaming did not occur in other stages, but doubtful in many cases instances of ‘dreaming’ in NREM were not reliable in the recordings & may have been from REM memories Based on data, dreams ‘occur in real time’ Comparing to previous studies, D&K said that previous methodology lacked enough measurements such as not amplifying the EEG enough or recording only samples of sleep

Strengths & Weaknesses Scientific/objective measurements, but the self report of dreaming & content was subjective Sample size and makeup (cannot generalize) No background provided for Ps (can be Ethnocentric) Method of waking subject may have influenced ability to recall dreams Correlation does not mean causation!

Ethical & Ecological Considerations Ethics (Remember, this predated strict guidelines) No mention of informed consent or rtw No significant harm or stress to Ps Ecological Validity- lab experiment lowers it Sleeping with wires on Sleeping being watched Sleeping in strange room

Usefulness Study was a generative one- it sparked new waves into sleep research Subsequent studies have not supported D&K’s findings that there is a relationship between eye movements and what the person is dreaming about Studies have claimed that NREM sleep can show similar EEG results and thus question the exclusiveness in REM sleep