New research shows that taste-related words, such as describing something as “sweet” or “bitter,” engage the emotional centers of the brain more than literal words with the same meaning.
For their study, researchers from Princeton University and the Free University of Berlin had volunteers read 37 sentences that included common metaphors based on taste while the scientists recorded their brain activity. Each taste-related word was then swapped with a literal counterpart so that, for instance, “She looked at him sweetly” became “She looked at him kindly.”
The researchers found that the sentences containing words that invoked taste activated areas known to be associated with emotional processing, such as the amygdala, as well as areas known as the gustatory cortices that allow for the physical act of tasting.
The researchers report that the metaphorical and literal words only resulted in brain activity related to emotion when part of a sentence, but stimulated the gustatory cortices when used both in sentences and as stand-alone words.
“Metaphorical sentences may spark increased brain activity in emotion-related regions because they allude to physical experiences,” said co-author Dr. Adele Goldberg, a professor of linguistics in the Council of the Humanities at Princeton.
She noted that language frequently uses physical sensations or objects to refer to abstract domains, such as time, understanding, or emotion. For instance, people liken love to a number of afflictions including being “sick” or shot through the heart with an arrow, she explained. Similarly, “sweet” has a much clearer physical component than “kind,” she noted.
“The latest research suggests that these associations go beyond just being descriptive to engage our brains on an emotional level,” she said. “This can potentially amplify the impact of the sentence,” she added.
“You begin to realize when you look at metaphors how common they are in helping us understand abstract domains,” Goldberg said. “It could be that we are more engaged with abstract concepts when we use metaphorical language that ties into physical experiences.”
If metaphors in general elicit an emotional response from the brain that is similar to that caused by taste-related metaphors, then that could mean that figurative language presents a “rhetorical advantage” when communicating with others, explained co-author Dr. Francesca Citron, a postdoctoral researcher of psycholinguistics at the Free University’s Languages of Emotion research center.
“Figurative language may be more effective in communication and may facilitate processes such as affiliation, persuasion, and support,” she said. “Further, as a reader or listener, one should be wary of being overly influenced by metaphorical language.”
Existing research on metaphors and neural processing has shown that figurative language generally requires more brainpower than literal language, according to the researchers. But these bursts of neural activity have been related to higher-order processing from thinking through an unfamiliar metaphor, they noted.
The brain activity observed in this study did not correlate with this process, according to the researchers.
In order to create the metaphorical- and literal-sentence stimuli, the researchers had a separate group of people rate sentences for familiarity, apparent arousal, imageability — which is how easily a phrase can be imagined in the reader’s mind — and how positive or negative each sentence was interpreted as being.
The metaphorical and literal sentences were equal on all of these factors, according to the researchers. In addition, each metaphorical phrase and its literal counterpart were rated as being highly similar in meaning, they noted.
“This helped ensure that the metaphorical and literal sentences were equally as easy to comprehend,” they said. This meant the brain activity the researchers recorded was not likely to be in response to any additional difficulty study participants had in understanding the metaphors.
“It is important to rule out possible effects of familiarity, since less familiar items may require more processing resources to be understood and elicit enhanced brain responses in several brain regions,” Citron said.
Citron and Goldberg said they plan to follow up on their results by examining if figurative language is remembered more accurately than literal language; if metaphors are more physically stimulating; and if metaphors related to other senses also provoke an emotional response from the brain.
The study was published in the Journal of Cognitive Neuroscience.
Source: Princeton University