AICE Psychology: Study - Dement and Kleitman

Relevant Background

Sleep is hard to study

Dreaming is hard to study

Psychological measures are required

In 1955 - used EEG to measure brain activity and eye movement during sleep

We go through several stages of sleep during the night

Go in and out of REM and NREM sleep

Vivid dreams are more likely to be remember during REM sleep

EEG produces chart showing frequency and amplitude of activity changes over time

The EEG can also be used to measure eye movement

How many aims?

three

First Aim?

Does dream recall differ between eye movement and dormant sleep?

Second Aim?

Is there a positive correlation between subjective estimates of dream duration and lengths of REM period before waking up?

Third Aim?

Are eye movements patterns related to dream content?

How many hypothesis are there?

Three

First hypothesis?

There will be a significantly association between REM sleep and dreaming.

Second hypothesis?

The length of REM and the subjective estimate of the length of dreaming will have a positive correlation.

Third hypothesis?

The pattern of eye movement will be related to the content of the dream to see if the movements have meaning or are random.

What type of study?

Lab Experiment

-(aim 1): repeated measures

-(aim 2):correlation using repeated measures

-(aim 3):self reports

How many independent variables were there?

three

How many dependent variables were there?

three

First IV?

woken during REM sleep and NREM

First DV?

if participant had dream recall

Second IV?

woke at 5 or 15 minutes

Second DV?

participants guess at length of time dreaming and word count on narrative of dream

Third IV?

direction of eye movement

Third DV?

report of dreaming or not and content of dream

Participants

9 people

- 7 male and 2 females

How were the participants studied?

Five were studied intensely, while the other four were used for confirmation

Sampling Techniques?

Volunteer sampling

How were they woken up?

A doorbell was used

Would the researcher ever come into the room?

Only occasionally if further questions were needed but most was done over a speaker

Restrictions on participants?

Were required to come to the lab at their bed time, and were not supposed to drink coffee or alcohol

What were the participants never told about?

The EEG

How the researcher decided to wake a participant?

- a random number

- in groups of three

- by telling them only in REM but would do both

- in no specific order

When would participants be waken up when the EEG was used to measure eye movements?

after the eye movement pattern had lasted for more than a minute

What eye patterns did they look for?

- vertical

- horizontal

- both vertical and horizontal

- very little or no movement

Data type?

quantitative and qualitative

What was the quantitative data?

Numbers of dreams recalled, numbers of time participants knew if they had been dreaming for 5 or 15 minutes, word count in dream narrative, and EEG measures

What was the qualitative data?

The dream narrative

General findings?

All participants dreamt every night

Uninterrupted dream stages lasted 5-30 minutes

Were typically later in the night

Intermittent eye movement between 2-100

Onset of sleep produced no eye movements

From one REM cycle to the next was between 70-104 minutes

When woken from NREM they returned to NREM

When woke from REM they wouldn't return to REM

How many stages are in the sleep cycle?

Four

Conclusions?

Dreaming is reported from REM but not nREm sleep

When given options of 5 to 15 minutes, they could judge how long they dreamt

REM patterns to dream content

Dreaming is more likely at the end of the night

Occasional recalls of dreams during nREM are likely to happen because of recall from last REM

Measurements show that dreams happen in real time

Strengths?

High control of extraneous variables

-waking during correct stages, using the doorbell to wake participants elimination of coffee

Low Demand Characteristics

- not being told when they were woken

Correlational study

-found positive correlation between REM sleep duration and number of words used in narrative

Operationalized "dream"

- participants had to have content of the dream not just a recollection or impression

Reliable measurements

- using the EEg

Weaknesses?

Potentially subjective

-the reports of the dreams

Small sample

- since there was more men than women

Low ecological validity

- since done in a lab

Possible ethnocentrism

- since only done in Chicago

How was the ecological validity?

It was low

Why was the ecological validity low?

Since it was in a sleep laboratory, normally not woken by a doorbell, since they had wires attached to them while sleeping, no consumption of things like coffee, and being observed while sleeping

Ethics?

Possible deception.

Participant WD was misled about when he was woken up.

Usefulness?

Further understanding of REM sleep and its link to dreaming and useful to scientists in this type of study

How it wasn't useful?

Low ecological validity and generalizability, and could possibly be ethnocentric, so it can't really used to be applied to other studies of sleep

Relation to Psych Approach?

Biological Psychology

- used sophisticated machinery

- has practical applications

- low ecological validity

- can be costly and time consuming

Relation to Psych Issue?

Used psychometrics

- used of EEG allowed for right wake times

- properly used correlation

- low ecological validity

Internal validity

how well an experiment controls the variables

REM

Rapid eye movement

nREM

non rapid eye movement

EEG

electroencephalogram

Frequency

number of events in a fixed period of time

- number of eye movements in an hour

Amplitude

the height of the waves on the EEG