Dement and Kleitman (1957) The relation of eye movements during sleep to dream activity: An objective method for the study of dreaming Dement & Kleitman (1957) 1 E. is a rock band formed in Athens. guitarist Peter Buck. Georgia in early 1980 by drummer Bill Berry. Dement & Kleitman (1957) 2 .What is REM? R.M. bassist Mike Mills and vocalist Michael Stipe. E.No.G.M.? It stands for Rapid Eye Movement It happens while you’re asleep You can see it happening when the sleeper’s eyes are closed You can measure it with a device called an ELECTROOCULAROGRAM (E.M.O. Dement & Kleitman (1957) 3 .E.) Aserinsky & Kleitman (1955) had already shown a link between dreaming and R. but what is R. really…. How else can you study dreaming? You can measure people’s BRAINWAVES while they’re sleeping You use a device called an ELECTROENCEPHALOGRAM (E.) which attaches to the scalp Dement & Kleitman (1957) 4 .E.G. 3 and 4 get deeper and deeper These stages are non-REM (NREM) sleep Stage 5.So what do we know? Cycle back through stages People go through different stages while they’re asleep Stages 1 is light sleep. you drop back to a lighter stage then repeat the cycle REM Dement & Kleitman (1957) 5 . is REM sleep After a while of REM. the deepest. stages 2. 2 women (volunteers) IV = woken in NREM or REM DV = self reports of dreaming Dement & Kleitman (1957) 6 .The Procedure Natural experiment in a lab setting Also: a controlled observation Sample: 7 men. 6 hours sleep Dement & Kleitman (1957) 7 .What happened? P’s turn up at the lab at bedtime They sleep attached to an EEG and an EOG A buzzer wakes them up at odd intervals They describe their dream into a tape recorder They are woken on average 5.7 times a night. Any controls? No alcohol or caffeine drunk 5 P’s studied intensively (6-17 nights). other 4 only studied for 1 or 2 nights This is to check sleep disruption isn’t affecting results No talking directly to a researcher (demand characteristics) Dement & Kleitman (1957) 8 . What was being tested? Did dreams happen during REM or during NREM? Did the duration of the dream match the duration of the REM? Did the content of the dream match the direction of the eye movements? Dement & Kleitman (1957) 9 . Do dreams happen in REM? Everyone had REM at some point in their sleep – often several times REM matches up with fast low-voltage brainwaves on the EEG REM lasts 3-50 minutes (average 20) and gets longer as the night goes on Sleepers woken in REM usually reported a dream Dement & Kleitman (1957) 10 . Let’s see that as a graph REM AWAKENINGS NON-REM AWAKENINGS Dement & Kleitman (1957) 11 . Show me the figures Pattern Dream? REM NREM 152 11 No recall 39 149 Total 191 160 Dement & Kleitman (1957) 12 . Explain the anomalies Half of the NREM dreams were reported within 8 minutes of leaving REM – maybe “remembered” dreams Most dream-less REM was early in the night Dement & Kleitman (1957) 13 . Let’s look at individuals Participant DN REM sleep 17/26 (65%) NREM sleep 3/24 (12½%) IR Does anybody stand out as “different”? KC 26/34 (76%) 36/40 (90%) 2/31 (6%) 3/34 (9%) WD PM 37/42 (88%) 24/30 (80%) Dement & Kleitman (1957) 1/35 (3%) 2/25 (8%) 14 . What about the length of dreams? P’s couldn’t estimate this. so researchers randomly woke them after 5 or 15 mins of REM and asked them to guess Most P’s could guess correctly So it looks like time passes in a dream the same way it passes in “waking” life Dement & Kleitman (1957) 15 . Let’s see that as a graph 5 MINUTES AFTER AWAKENING 15 MINUTES AFTER AWAKENING Dement & Kleitman (1957) 16 . Show me the figures Estimate Match 5mins 45 15mins 47 13 60 17 No match 6 Total 51 Dement & Kleitman (1957) . climbing a ladder.What about the direction of eye movements? VERTICLE movements (3 out of 35) Looking up a cliff. aiming basketballs at hoops HORIZONTAL (1 out of 35) Watching two people throw tomatoes at each other BOTH TYPES (21) Looking at things close up NO MOVEMENT (10) Looking at things in the distance Dement & Kleitman (1957) 18 . Discussion Does the evidence support the idea of dreams occurring in REM? Do dreams occur at the same rate as “real” experiences? Does REM reflect what you’re “looking at” in your dream? What problems are there with this sample? Does this study have ecological validity? How else can dreams be studied? Dement & Kleitman (1957) 19 .