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Katrien Segaert defends PhD on February 20
Katrien Segaert of MPI's Neurobiology of language department will defend her thesis 'Structuring language: Contributions to the neurocognition of syntax' on February 20 at 13:30, in the Radboud University aula. She found, among other things, that speakers are strongly inclined to re-use syntactic structures in new sentences.
February 16, 2012
When speakers convey a message using language, listeners have to retrieve its meaning and the intention of the speaker. In order to accomplish this, they must recognise words in an incoming stream of speech sounds, using information about their phonological, semantic and syntactic properties. All this information is stored in our long-term memory, or what psycholinguists call the mental lexicon. Listeners use these building blocks to derive a syntactic structure and an interpretation for a combination of words or a sentence. Speakers complete the same processes in the reverse order. In her dissertation, Katrien Segaert focussed on the retrieval and combination of syntactic information: syntactic processing.
Same structure as used before
When speakers produce a sentence, they are strongly inclined to use the same syntactic structure as the sentence they uttered previously. After using a passive syntactic structure like The woman is greeted by the man, for instance, speakers tend to use a passive structure in their next utterance as well. The reason is that speakers implicitly learn from re-using syntactic structures -- an effect referred to as syntactic priming. "The tendency to re-use syntactic structures is particularly strong for complex syntactic structures, because they are used less frequently and therefore have a stronger syntactic priming effect," Segaert explains. "For simple syntactic structures this tendency is less strong, but if speakers do use the same syntactic structure the sentences are produced faster."
Syntactic processing in the brain
"Our fMRI studies also demonstrated that repeating syntactic structures facilitates sentence production and comprehension," she says. Syntactic processing involves two regions in the brain, the left inferior frontal gyrus and left middle temporal gyrus. Segaerts' experiments indicate that these regions show a lot of activation when syntactic structures are used for the first time, but less activation when structures are used for a second time. "Particularly striking is that these brain regions support syntactic processing during both speaking and listening. My dissertation studies thus support one processing mechanism for both syntactic production (speaking) and comprehension (listening) instead of two separate systems."