Making sense of discourse: An fMRI study of causal inferencing across sentences

Narrative speech production: An fMRI study using continuous arterial spin labeling

“…For example, the dorsal portion of left inferior frontal cortex was recruited. This area was reported by Braun et al (2001) in their PET study of discourse, and by Kuperberg et al (2006) in their study of discourse judgments. This may be related to the working memory component needed to maintain elements of the narrative in an active state during its production.…”

“…Braun et al (2001) and Kuperberg et al (2006) also observed this distribution of temporal-occipital activation in their studies of discourse, even though no picture stimuli were involved, and related this posterior activation to a semantic component of the story. Given the closely matched baselines in the present study, we endorse Kuperberg's (2006) specific proposal that this activation may be related in part to the inferences about meaning that are derived from an extended narrative, that is, beyond the meaning available from direct inspection of a stimulus picture or sentence. This interpretation is also consistent with work showing visual association cortex recruitment during semantic memory challenges (Martin, Ungerleider & Haxby, 2000).…”

“…The activation may have been significant in the left hemisphere because the speech was meaningful. However, this would not explain activation in this area during the comprehension study of Kuperberg et al (2006) where there was no auditory stimulation. We therefore believe the interpretation that temporal-parietal activation indicates a semantic support region important for making story inferences beyond what is available in the picture.…”

“…This suggests an important role for this inferior frontal region in narrative discourse. Another carefully controlled study of discourse organization by Kuperberg et al (2006) reported frontal activation during coherence judgments rather than narrative production. They attributed frontal recruitment to the controlled activation of semantic information, as described in studies involving single words and pictures (Badre & Wagner, 2004;Thompson-Schill, D'Esposito, Aguirre, & Farah, 1997;Thompson-Schill, Aguirre, D'Esposito, & Farah, 1999;Wagner, PareBlagoev, Clark, & Poldrack, 2001).…”

“…A more explicit approach to the evaluation of narrative reported left medial prefrontal activation during explicit judgments of the coherence of pairs of sentences (Ferstl et al, 2002) or coherence judgments depending on the presence of definite articles (Robertson et al, 2000). In two recent studies, subjects were asked to judge the relatedness of a third sentence to two prior sentences establishing the scene (Kuperberg, Lakshmanan, Caplan, & Holcomb, 2006;Mason & Just, 2004). This work reported bilateral frontal, temporal, and parietal activation that was greatest for stimuli demanding a coherent linkage between sentences.…”