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Abstract:
Comprehending connected text (as opposed to unrelated
sentences) results in more neural activity in the right- than the
left-hemisphere of the frontal lobe, as measured by functional
magnetic resonance imaging (fMRI). This finding corroborates the
behavioral challenges that patients with right-hemisphere brain
damage face during language comprehension. In the present fMRI
experiment, we measured brain activity while subjects comprehended
written narratives as well as narratives told completely without
words (i.e., picture stories). Reading narratives was alternated
with reading independent, unrelated sentences, and comprehending
picture narratives was alternated with viewing independent,
unrelated pictures. The brain regions that showed increased
activity while subjects comprehended written stories (compared with
reading unrelated sentences) were strikingly similar to the brain
regions that showed increased activity while subjects comprehended
pictures stories (compared with viewing unrelated pictures).
Principal activations were observed in right superior temporal
sulcus, precuneus, and parieto-occipito-temporal regions
bilaterally. Right dorsolateral prefrontal activity was observed
during comprehension of written stories. These findings replicate
the finding that the right hemisphere is involved in comprehension
processes that link ideas between sentences. That similar results
were found for both verbal and non-verbal media suggests a common
neural circuit for comprehension, and supports theories that
propose that language comprehension is based on general cognitive
processes.
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