Pronouns light up brain!

Aug 17 2007

New research suggests that pronouns may play a far greater role than simply replacing a proper name in a sentence. A University of South Carolina study suggests that pronouns help keep the brain's complex circuitry and limited memory system from being overloaded.

Using fMRI (functional magnetic resonance imaging), psychology researcher Dr. Amit Almor and colleagues studied the brain activity of 21 adults, ages 19 - 34, who were asked to read sequences of sentences to compare the brain's response to pronouns versus proper names.

Almor's findings are featured in the cover article in the current issue of the NeuroReport, a scientific journal.

“The brain lit up with activity when proper names were used, including areas that are not associated with language,” Almor said. “We saw considerable activity in areas of the parietal lobe that involve spatial processing that was absent when pronouns were used.”

Almor is the first researcher to use brain imaging to explore the neurological underpinnings of humans' preference for pronouns. He conducted his research at the university's McCausland Center for Brain Imaging.

The brain responds to proper names by creating a representation of the person in the mind, drawing from various parts of the brain to construct complex visual, sound and other information associated with that person. Every time the name is repeated, the brain responds by activating a process that creates a new representation of the person.

The brain initially holds each created representation in memory. The integration of these multiple representations requires effort that can disrupt the brain's ongoing processing of what it hears during spoken conversation.

Pronouns, while faulty for their potential ambiguity, don't cause the same disruptions in the brain that proper names do when used in the right context. In fact, they allow the brain to move easily from one thought or sentence to another. This seamless transition allows a person to digest more fully the meaning or intent of the thought being conveyed without the neural circuitry interference that proper names cause, said Almor.

“We are at the mercy of our memory system, which is limited,” Almor said. “The more items or representations we hold, the more effort we need to spend so as not to lose information. Pronouns let us avoid that juggle in our brains. I expected to find activity in classic language areas of the brain. I was surprised to see activity in the spatial areas, but it makes perfect sense.”

Almor says American Sign Language uses a similar system to protect the brain from such “juggling.” In ASL, a person will sign a proper name on first reference and then point to a specific location in the air, as if “placing” that name on an invisible computer desktop. Instead of re-signing the name, which causes the brain to create a new representation of that person, the signer will point to where he or she had “placed” that name so that the other person will understand to whom he or she is referring.

“Language has evolved to meet our brain's needs, and sign language is no different,” said Almor. “In fact, although sign languages are often studied through comparison to spoken languages, in this case sign language may show the internal working of the brain's language ability more transparently than any spoken language.”

“Our study suggests that, just like signers, English speakers place people that were previously mentioned in space, although in the case of English speakers, this space is a ‘virtual' brain space.”

Almor plans further fMRI-based studies to understand the relationship between language and brain function.

Almor's research, which reveals the brain circuitry behind language, may help researchers who study topics that range from language acquisition and brain injury/recovery of function to Alzheimer's disease and Autism.

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