Saying, and Hearing, the "Thing Which Is Not"

Lying, irony, and the neural gymnastics required to make sense of them.

Posted Feb 16, 2018

In Jonathan Swift’s satirical novel Gulliver’s Travels, the sea-faring Lemuel Gulliver tries to explain human nature to a member of a species of intelligent and purely rational horses called Houyhnhnms. When Gulliver mentions the human penchant for “lying and false representation,” the Houyhnhnm expresses bafflement, unable to comprehend why any rational creature would say “the thing which was not”. Since the notion of lying is so contrary to the fundamental purpose of language that the Houyhnhnms don’t even have a word for it.

Pixabay / CC0 Public Domain
Source: Pixabay / CC0 Public Domain

While we humans are so accustomed to saying, and hearing, “the thing which [is] not” that we barely raise an eyebrow when it occurs, observing the Houyhnhnm’s complete mystification over this tendency causes us to step back and appreciate how complex—and often seemingly irrational—our use of language really is. We quite routinely utter speech acts that appear to violate the fundamental communicative purpose of language by stating the opposite of what we know to be true, and yet in spite of—and quite often even because of—these violations, we traffic in subtle nuances of meaning that would utterly escape the completely rational truthfulness of the Houyhnhnms. Recent research in the neuroscience of language processing has indicated that the mystification of Gulliver’s equine host over human language use is justified. Saying, and more importantly understanding, "the thing which is not" is a far more complex process than the literal language use to which the Houyhnhnms are accustomed.

Several studies in the past few years have explored what goes on in our brains when we are confronted with speech acts that are intentional violations of factual truth. Decoding speech acts in which there is no discrepancy between literal meaning and the speaker’s communicative intention is a feat of neural gymnastics in its own right, but when such a discrepancy does exist, recognizing the gap between utterance and intention requires even more specialized processing that involves the recruitment of extended cerebral networks. Neuroimaging studies have shown that comprehending both deceit and irony—the two most common categories of nontruthful language use—involves the activation of a “left fronto-temporal network” that includes the inferior frontal gyrus, the dorsolateral prefrontal cortex, and the middle frontal gyrus. A recent study at the University of Turin probed even more deeply to see if distinguishing between deceit and irony requires even further specialization of neural resources.

Subjects in the study were presented with forty-eight short stories followed by a target sentence the meaning of which was either literal, deceitful, ironic, or meaningless, depending upon the context established by the story. For example, the target sentence of one of the story sets was, “It’s a beautiful day.” In one of the stories that preceded the sentence, a man and a woman are planning to take a trip to the mountains. The woman asks the man what the weather is like, and looking outside and seeing the sun shining replies, sincerely, “It’s a beautiful day.”  In a second story, a man is trying to persuade a woman to take a trip to the beach with him, but she says she will only go if the weather is nice. Even though he knows that rain is forecast for the day, he really wants her to go so he says, deceitfully, “It’s a beautiful day.” In a third story, a man and a woman drive to the countryside to have a picnic. Just as they get out of the car they hear thunder and feel drops of rain. As they exchange doubtful glances, the woman says, ironically, “It’s a beautiful day.” A fourth story, provided as a control, created a context in which the statement was meaningless.

As in prior research distinguishing between literal and non-literal language use, the study revealed the activation of common brain regions (left inferior frontal gyrus, middle frontal gyrus, dorsolateral prefrontal cortex, and right cerebellum) in the comprehension of both deceitful and ironic responses, as compared to the comprehension of the literal response. When brain activation patterns related to the comprehension of deceit and irony were directly compared to each other, however, yet another distinction appeared. Distinguishing between a deceitful speech act and an ironic speech act specifically activated a brain area—the left middle temporal gyrus—that was not activated in the general distinction between true and untrue utterances.

Recognizing a discrepancy between the semantic content of a speaker’s utterance and its actual pragmatic meaning—whether deceitful or ironic-- involves a recognition of a speaker’s communicative intention, which “is a high-level process that recruits extended cerebral networks.” When the intention behind the discrepancy is irony rather than deceit, however, recognizing that intention places an even higher cognitive demand upon the listener, who must not only perceive the untruthfulness of the utterance, but understand that the speaker intends for him or her to perceive the untruthfulness, and furthermore decode this mutually shared untruthfulness for the speaker’s actual meaning. The authors of the study speculate that the “recruitment of the lMTG could sustain the additional inferences necessary to comprehend irony with respect to deceit.”

Jonathan Swift intended Gulliver’s encounter with the truth-telling Houyhnhnms to demonstrate how irrational human beings are for routinely exchanging utterances that do not accurately represent the world as we know it to be. Rational or not, our human fondness for playing fast and loose with the factual truth allows us to do things with language that communicate far more subtle nuances than a purely straightforward, literal use of language ever could—while admittedly not always with the best of intentions. Our playful attitude toward language is one of our defining features that makes us—to use a purely non-literal comparison—humans rather than horses.

References

Bosco, F.M., Parola, A., Valentini, M. C., & Morese, R. (2017). "Neural Correlates Underlying the Comprehension of Deceitful and Ironic Communicative Intentions." Cortex, 94: 73-86.

Swift, Jonathan. Gulliver's Travels. Penguin Classics, 2003.

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