REM--The Royal Road to Metaphor
Not only is metaphor a major literary device, but it is crucial to how dreamers translate images and ideas into stories. Bert O. States considers metaphor as “the smallest and most salient unit of artistic or imaginative energy” (104). Taking that into consideration, creative writers need to tap into that energy in developing their writing and dreams can help them do that. 
Like Hartmann, States regards metaphor as a symbiosis of ideas. He calls metaphor “the cognitive fire that ignites when the brain rubs two different thoughts together” forming a “cognitive expansion of their combined possibilities on which future likenesses may be built” (105). Robert Stickgold’s view of cognitive flexibility is similar: “To be creative, you need a way to let those circuits float free and really be open to alternatives that you would normally overlook . . . Several features of REM sleep predispose the brain to this activity” (DeAngelis). However one describes it, metaphor is a powerful tool in any creative person’s arsenal.
Writers regularly employ metaphor so it seems possible that they may be more receptive to the metaphors they encounter in dreams. A study published in the Journal of Cognitive Neuroscience concurs with the theory of the enhancement of cognitive flexibility from REM sleep, but takes it a step further. They discovered that REM dreams can also unlock the secrets of metaphor. The study observed that “the bizarre and hyperassociative character of REM” affected subjects’ answers to semantic priming tests. Participants were awakened from NREM and REM sleep periods to take a series of word priming tasks. Subjects were shown a “prime” word, followed by a “target” word and were asked to determine how the target word was analogous to the prime word. For example, a strong prime would be “cat/kitten” or “light/dark”; a weaker prime would be “beach/summer” or “crime/gun.” The researchers also introduced pairs of words that had no semantic relationship, like “apple/roof” and “fork/baseball.” Nonsensical word pairs were also thrown into the mix. 
The study showed that subjects who took the test shortly after REM sleep had slower responses to the stronger primes and had an easier and faster response to weaker primes. It seems like the participants transcended direct and logical thought to more complex and creative thought. “It’s as if the brain is preferentially searching out and activating weak associates, unexpected paths, instead of the obvious, normally strong associates,” observes Robert Stickgold, one of the researchers (qtd. in DeAngelis).
The results indicate that dreamers under the influence of REM sleep can develop unique and creative metaphors in waking life. By finding a connection between weak primes, writers can create vivid and original metaphors. Writers are constantly devising new ways of looking at things; often they assign significance and symbolic meaning to objects. A cognitively flexible writer uses free association to mine new ideas with confidence, not self-censure.
Read more:
Introduction--The Committee of Sleep
Dream Incubation
REM--Making the Connection
REM--The Royal Road to Metaphor
Hypnagogic Dreams
Writer's Block
The Little People
Suggested Reading
Links
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