Neuroanatomical distinctions within the semantic system during sentence comprehension: Evidence from functional magnetic resonance imaging

Abstract

To make sense of a sentence, we must compute morphosyntactic and semantic-thematic relationships between its verbs and arguments and evaluate the resulting propositional meaning against any preceding context and our real-world knowledge. Recent electrophysiological studies suggest that, in comparison with non-violated verbs (e.g. "...at breakfast the boys would eat..."), animacy semantic-thematically violated verbs (e.g. "...at breakfast the eggs would eat...") and morphosyntactically violated verbs (e.g. "...at breakfast the boys would eats...") evoke a similar neural response. This response is distinct from that evoked by verbs that only violate real-world knowledge (e.g. "...at breakfast the boys would plant..."). Here we used fMRI to examine the neuroanatomical regions engaged in response to these three violations. Real-world violations, relative to other sentence types, led to increased activity within the left anterior inferior frontal cortex, reflecting participants' increased and prolonged efforts to retrieve semantic knowledge about the likelihood of events occurring in the real world. In contrast, animacy semantic-thematic violations of the actions depicted by the central verbs engaged a frontal/inferior parietal/basal ganglia network known to mediate the execution and comprehension of goal-directed action. We suggest that the recruitment of this network reflected a semantic-thematic combinatorial process that involved an attempt to determine whether the actions described by the verbs could be executed by their NP Agents. Intriguingly, this network was also activated to morphosyntactic violations between the verbs and their subject NP arguments. Our findings support the pattern of electrophysiological findings in suggesting (a) that a clear division within the semantic system plays out during sentence comprehension, and (b) that semantic-thematic and syntactic violations of verbs within simple active sentences are treated similarly by the brain.

Disentangling meaning in the brain: Left temporal involvement in agreement processing

“…These could be precisely the mechanisms that led to the involvement of this fronto-parietal regions in our experiment, during which participants were required to evaluate sentence grammaticality. Importantly, this finding is consistent with other sentence processing studies that required the evaluation of the morphosyntactic fit in a variety of dependencies (Folia et al 2009;Kuperberg et al 2003Kuperberg et al , 2008Nieuwland et al 2012). Further corroboration 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 27 for this interpretation comes from the fact that both person and number agreement violations elicit a P600 (cf.…”

“…These data appear in line with those 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 (Kuperberg et al 2003(Kuperberg et al , 2008 and verb-object violations in Basque (Nieuwland et al 2012)]. A number of studies point to a critical role of the middle frontal gyrus in domain-general verbal working memory mechanisms (see Katsuki and Constantinidis, 2012 and Rogalsky and Hickock, 2011 for reviews).…”

“…We therefore expect recruitment of conflict-monitoring areas, including the dorso-lateral prefrontal cortex and the anterior cingulate cortex bilaterally, to emerge from the comparison between the two violations and correct agreement (Agreement Violation > Correct Agreement contrast). Previous work on the processing of agreement and other morphosyntactic dependencies has consistently demonstrated the involvement of this network as a result of a (task-driven) mismatch detection process (see Van de Meerendonk et al 2009 for a review; Kuperberg et al 2008;Nieuwland et al 2012;Quiñones et al 2014). …”

“…If this is on the right track, we expect agreement violations to show partially common patterns with Correct Agreement in areas engaged in the building and interpretation of agreement dependencies. Previous work (Kuperberg et al 2003(Kuperberg et al , 2008Quiñones et al 2014) points to cortical areas that are part of the language network, such as the LIFG and the MTG, as primarily involved in the comprehension of congruent sentences. Within this network, the finding of differential responses for Person and Number Violations (Person Violation > Number Violation) would provide evidence for featurespecific mechanisms in the building and interpretation of a sentential relation, in line with theoretical analyses (Bianchi, 2006;Mancini et al 2013;Sigurdsson, 2004Sigurdsson, , 2008.…”

Monitoring in language perception: Electrophysiological and hemodynamic responses to spelling violations

“…Kuperberg et al (2008) tested 'animacy semanticthematic violations' (see also Kuperberg et al, 2006). The following is an example: (3) Every morning at breakfast the eggs would eat … In this sentence, the syntactic parse indicates that the noun phrase (NP) the eggs is the agent of the sentence and therefore eat would be a syntactically correct verb form.…”