Semantic integration in reading: engagement of the right hemisphere duringdiscourse processing

We examined the brain areas involved in discourse processing by using funct ional MRI in 10 individuals as they read paragraphs, with or without a titl e, word by word for comprehension. Functional data were collected from 20 a djacent 5 mm axial slices, Discourse processing was associated with activat ion in inferior frontal and temporal regions of both cerebral hemispheres i n the titled and untitled conditions, Moreover, there was substantially mor e right hemisphere activation for untitled than for the titled paragraphs. More specifically we found: (i) greater activation in the inferior temporal sulcus of both hemispheres for untitled than titled paragraphs; (ii) great er average volume of activation in response to untitled than titled paragra phs in the middle temporal sulcus of the right hemisphere and the reverse p attern in the left middle temporal sulcus, Consistent with previous studies of individuals with right hemisphere damage, we suggest that the right mid dle temporal regions may be especially important for integrative processes needed to achieve global coherence during discourse processing.