There is little doubt that dreams could be influenced prior to sleep. Lab and field researchers had the dreamers drink great amounts of liquid to induce bladder tension, or deprived them of fluids and fed them salty foods. They placed crushed cloves on their tongues, gave them pre sleep suggestions to dream about certain topics or had them read brief but vivid stories. During the day, subjects were shown romantic, erotic or disturbing films. Or given red-colored goggles to wear all day for 5 days in a row. Especially if it is a novel experience, what happens just before sleep can have the strongest influence on dreams. That's why, no matter what the stated reason for the experiment, many subjects in a sleep laboratory will find themselves dreaming about...the sleep lab. A few will dream literally of preparations for sleep - interacting with the experimenter, walking around in pajamas, or wearing the electrodes that relay information about their brain waves, eye movement and muscle tension. More often, these pre-sleep events will be transformed, although sensory sub-features and analogy clues can quickly unlock the connections.

Literal Descriptions of a Swiss Sleep Lab

Analogous Dream Responses

Sub-features Used in the Analogy

Electrodes are glued to several spots on the subject's scalp to permit EEG recording.	"A bee comes from somewhere and tries to build a nest in my hair"	pressure and weight
The electrodes are disks of gold.	a jewelry setting, but without the gem	size and luster
Each electrode is attached to a thin cable; the cables are plaited together.	bottles that "talk to each other," covered with braided straw	line and texture
The electrodes are plugged into a box above the bed. A microphone also hangs above the bed to relay the subject's oral report.	Grandmother carries a small parcel and hangs out the laundry	relative position and silhouette
Through a speaker the experimenter calls the subject by name...	" Run ahead and ring the doorbells and yell out our names."	volume and tone
...to awaken her several times during the night. After relaying her dream report, the subject returns to sleep.	jumping from one streetcar to another after another a number of times	timing and number
An adjacent room contains a polygraph that measures and graphically displays the rhythms of the body and brain...	a train that "kept going uphill and downhill ­ uphill...moving on and on and on."	rhythm and duration
...on rolls of paper about 300 meters in length.	a rolled art canvas with a U-shaped crochet pattern on it	size and curvature

A Perceptive Dream Illustrates General Impressions

These dreams created images that were not clones of the sleep lab description for a very simple reason. Dreams do not speak language. They draw pictures. They illustrate experience. And the type of experience they usually portray is original artwork of a general impression. By comparing dream and waking events, we can determine the general impression that underlies each event.

...something touches my head...something is small, shiny and wearable...something is braided...something is hanging in the air...something alerts me by calling my name...something keeps switching the flow of my thought...something that I can see go up and down...something looks long, flat and rolled up...

General impressions are outlines of experience that tend to register more easily than complex memories of events. Nevertheless, we do have detailed pictures from the past in our memory data banks. The dream takes a current brief outline of events and fills in the blanks with older detailed images. It garnishes the bare structure of impression with flourishes drawn from personal memory.

Perceptual analogy = general impression + specific memory

Because the source of memories is unique for every individual, we won't all decorate our impressions the same way. In this experiment, two other dreamers took the impression of something hanging in the air and pictured it as a balloon. For another dreamer, the rude awakenings through a speaker were likened to radio noise she wanted turned down because the volume was too loud. The polygraph readings had several versions: a bumpy road, a small car that would "scoot, hither and yon" and a rocket that took off skyward, fell towards the earth and soared upwards again. The rolls of polygraph paper became a perforated roll of tickets and a bed roll with a zipper.

We don't know why these particular alternative images were painted atop the general impressions of the same daytime events. We can't interview the subjects for their input. Only the dreamers are privy to their own memory banks. Only they can answer "Where did that come from?" and figure out the sorts of analogy their sleeping minds are apt to create.

The subjects in this experiment arrived at the laboratory only an hour before sleep. Yet, about one-third of their dreams reflected the laboratory setting and activities. What happens to you right before you go to bed? A late night talk show on TV might provide something for your mind to mull over or chuckle about. But the tragedies on the 11 o'clock news can induce nightmares.

Reference

Strauch, Inge and Barabara Meier. In Search of Dreams/Results of Experimental Dream Reasearch. (Albany, NY: State University of New York Press, 1996).