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Abstract:
Abstract: We conducted parallel studies using event-related
potentials (ERPs) and event-related fMRI to investigate the neural
networks mediating syntactic and pragmatic processing of sentences.
In both studies, the same fourteen subjects viewed three sentence
types: normal, pragmatically - and syntactically-anomalous,
presented word-by-word . Identical stimuli were used in the two
studies, although no participant saw the same sentences twice. The
ERP experiment revealed a bilaterally, posteriorly-distributed N400
component to pragmatic anomalies and a more right-sided
posteriorly-distributed P600 component, to syntactic anomalies.
Event-related fMRI revealed left-sided activity in the posterior
superior and middle temporal gyrus (Wernicke's area: BAs: 21 and
22) and in the inferior frontal gyrus (BAs:47,10,11). This activity
was modulated at the time-point in the hemodynamic response that
corresponded to when an anomaly differentiated the sentence-types:
maximal activity was seen in association with
pragmatically-anomalous sentences, less with normal sentences, and
least with syntactically-anomalous sentences. Intriguingly,
right-sided posterior parietal areas that were `deactivated' in
comparison with a fixation condition, were reciprocally modulated
according to sentence-type , with least `deactivation' in
association with syntactically-anomalous sentences. These fMRI
results do not suggest that pragmatic and syntactic processing are
neurally dissociated, but rather suggest that activity within the
same neural networks is modulated according to the type of
linguistic information being processed.
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