Key Study: Dement & Kleitman (1952) ‘The relation of eye movement during sleep to dream activity: an objective method for the study of dreams’ Key Study: Dement & Kleitman (1952)

Why do we dream? Freud: argued that the purpose of dreaming is to unconsciously fulfil wished which would otherwise upset and therefore disturb the sleeper. Dreams are the ‘Royal road to the unconscious’ so they provide the therapist with insight into the clients unconscious thoughts

Why do we dream? Cognitive explanations: a way of dealing with our problems such as those relating to work/ school or our personal life Physiological explanations: a result of random firing of neurons which create an image which we then put meaning to

Sleep and dream states Every 24 hours we sleep we spend 30% of our lives asleep sleep is an active NOT a passive behaviour

Stages of sleep We pass through different levels of sleep in a cyclic fashion between 5 and 7 times a night. Stage 1 and 2 are light sleep characterised by irregular EEG patterns Stage 3 and 4 are deeper levels and are characterised by regular wave patterns Stage 4 is slow wave sleep or deep sleep Then we go back up the staircase to stage 2 Then we enter REM sleep which lasts 15-20 minutes

The Stages of Sleep The shaded areas are REM sleep

The Stages of Sleep

What is REM Sleep? Rapid Eye Movement The eyes dart back and forth very quickly we are asleep yet our brain is as active as when we are awake Closely associated with dreaming

Sleep deprivation studies: Human sleep deprivation? REM sleep seems important: The Randy Gardner study volunteers who are gradually deprived of sleep (sleep reduced from 8 hours to 2 hours) They pack REM sleep into the time they CAN sleep

How Do We Study Sleep? Wire P’s to an electroencephalogram (EEG) This measures the electrical activity in the brain and amplifies it. It is non-invasive and should not disturb sleep too much.

The Study Kleitman is recognised as the first researcher to effectively study sleep. Wanted to find an objective method to study sleep and in particular REM sleep.

The Aims There will be a significant association between periods of REM sleep and dreaming? There will be a significant positive correlation between the estimate of dream length and time in REM? There will be a significant association between the pattern of eye movement and the context of the dream

Sample 9 participants 7 adult males 2 adult females 5 studied intensively and only small amount of data collected on the other 4.

Procedure Studied under controlled laboratory condition P’s Attend lab at usual bed time. Ate normally but no alcohol or caffeine before sleeping. They went to bed in a quiet dark room, they were wired to EEG (eyes and scalp).

Hypothesis 1: There will be an association between REM and dreaming They were woken by a bell placed next to the bed when woken the Ps spoke into a recording device near the bed FIRST - they said whether they had been dreaming NEXT they said what they were dreaming about (if they could) Ps were recorded as dreaming if they could relate a detailed description of the dream

Different participants were woken at different times 2 woken at random 1 woken 3 times in REM and 3 times in N-REM 1 woken at random but told that he was woken in REM Another woken at the experiments whim

Hypothesis 2: there will be a correlation between the duration of dreams and the length of eye movement Ps woken up 5 mins or 15 mins into a REM period Ps asked if they had been dreaming for 5 or 15 mins

Hypothesis 3: there will be an association between pattern of eye movement and dream content Ps woken up when one of 4 patterns of eye movement lasted more than a minute Vertical Horizontal Both vertical and horizontal Very little or no eye movement Ps asked to describe content of their dream

Controls: No communication between experimenter and sleeper until after they told of their dream content in case the experimenter ‘suggested the content’ (experimenter effects) They were NOT told whether they had been woken in REM sleep or in NREM sleep Woken in BOTH REM and NREM

Results: Hypothesis 1: There will be an association between REM and dreaming REM associated with dreaming and NREM associated with non-dreaming sleep. Reports of NREM dreaming (usually reported just after REM activity) explained by memory of REM dreams.

Results: Hypothesis 2: there will be a correlation between the duration of dreams and the length of eye movement All Ps were able to choose the correct dream duration fairly accurately (except for one participant who underestimated the length of his dreams)

Results: Hypothesis 3: there will be an association between pattern of eye movement and dream content Relationship between pattern of eye movement and content of dream

Vertical eye movement Standing at bottom of cliff and looking up at climbers and down at hoist machinery looking up down while climbing a ladder Throwing basketballs at a net, looking up at net then down to pick up ball

Horizontal eye movement Mixture of eye movement Watching two people throwing tomatoes at each other Mixture of eye movement Ps looking at people close to them (talking to people, looking for something, fighting with someone) No eye movement Ps looking staring at an object or watching something in the distance

Evaluation of the study Lack of ecological Validity Sample size (ethnocentric sample) Tightly controlled method - reliable

Advantages of a Lab Experiment P - Lab experiments have a high level of control over variables E – C - Therefore the lab experiment is more reliable as its easier to replicate and get the same results P - An advantage of a lab experiment is that it allows us to infer cause and effect (IV causes DV) C - Therefore is tells us not only that there is a relationship, but the direction of the relationship

Disadvantages of a lab experiment P - Lab experiments lack of ecological validity E – C - Therefore the findings cannot be generalized beyond experimental setting P - Demand characteristics are a disadvantage of lab experiments because participants are aware they are being observed C - Therefore lab experiments lack validity as they may not truly be measuring what they claim to measure.

Does it matter that only 2 Ps were female? QUESTIONS Does it matter that only 2 Ps were female? Why were Ps asked to refrain from alcohol / caffeine? Why was it important that the Ps did not know whether they were in REM or NREM? Does the size of the sample matter? Why might the sleep patterns be different when the Ps sleep in their own beds?

Why might some of the Ps have recalled dreams when they were woken in NREM? To whom can we generalise the findings? Was the study ethical? What was the IV? What were the three DVs? Have D & K established that dreaming ONLY occurs in REM sleep?