Reviewing the functional basis of the syntactic Merge mechanism for language: A coordinate-based activation likelihood estimation meta-analysis

118

Comprehending and producing sentences is a complex endeavor requiring the coordinated activity of multiple brain regions. We examined three issues related to the brain networks underlying sentence comprehension and production in healthy individuals: First, which regions are recruited for sentence comprehension and sentence production? Second, are there differences for auditory sentence comprehension vs. visual sentence comprehension? Third, which regions are specifically recruited for the comprehension of syntactically complex sentences? Results from activation likelihood estimation (ALE) analyses (from 45 studies) implicated a sentence comprehension network occupying bilateral frontal and temporal lobe regions. Regions implicated in production (from 15 studies) overlapped with the set of regions associated with sentence comprehension in the left hemisphere, but did not include inferior frontal cortex, and did not extend to the right hemisphere. Modality differences between auditory and visual sentence comprehension were found principally in the temporal lobes. Results from the analysis of complex syntax (from 37 studies) showed engagement of left inferior frontal and posterior temporal regions, as well as the right insula. The involvement of the right hemisphere in the comprehension of these structures has potentially important implications for language treatment and recovery in individuals with agrammatic aphasia following left hemisphere brain damage.

Section: Discussionmentioning

confidence: 52%

Neural networks for sentence comprehension and production: An ALE‐based meta‐analysis of neuroimaging studies

Walenski

Europa

Caplan

et al. 2019

118

“…In order to identify brain systems involved in combinatory processing, many neuroimaging studies using functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) have utilized contrasts of structure, comparing highly structured stimuli such as sentences (e.g., the poet will recite a verse ) to less structured stimuli such as word lists (e.g., rabbit the could extract catch protect ). The key assumption is that brain areas engaged in syntactic and semantic combinatory processing will show increased activation to sentences, while noncombinatory effects of sensory, attentional, and lexical processing are subtracted out (Fedorenko, Nieto‐Castanon, & Kanwisher, ; Humphries, Binder, Medler, & Liebenthal, ; Humphries, Love, Swinney, & Hickok, ; Matchin, Hammerly, & Lau, ; Mazoyer et al, ; Pallier, Devauchelle, & Dehaene, ; Rogalsky & Hickok, ; Stowe et al, ; Vandenberghe, Nobre, & Price, ; see Zaccarella, Schell, & Friederici, , for a meta‐analysis and review). While there is some degree of variability across studies, four broad portions of the left hemisphere reliably show effects of sentence structure: the temporo‐parietal junction (TPJ), the anterior temporal lobe (ATL), the posterior temporal lobe (PTL), and the inferior frontal gyrus (IFG) .…”

Section: Introductionmentioning

confidence: 99%

The temporal dynamics of structure and content in sentence comprehension: Evidence from fMRI‐constrained MEG

Matchin

Brodbeck

Hammerly

et al. 2018

Humans have a striking capacity to combine words into sentences that express new meanings. Previous research has identified key brain regions involved in this capacity, but little is known about the time course of activity in these regions, as hemodynamic methods such as fMRI provide little insight into temporal dynamics of neural activation. We performed an MEG experiment to elucidate the temporal dynamics of structure and content processing within four brain regions implicated by fMRI data from the same experiment: the temporo‐parietal junction (TPJ), the posterior temporal lobe (PTL), the anterior temporal lobe (ATL), and the anterior inferior frontal gyrus (IFG). The TPJ showed increased activity for both structure and content near the end of the sentence, consistent with a role in incremental interpretation of event semantics. The PTL, a region not often associated with core aspects of syntax, showed a strong early effect of structure, consistent with predictive parsing models, and both structural and semantic context effects on function words. These results provide converging evidence that the PTL plays an important role in lexicalized syntactic processing. The ATL and IFG, regions traditionally associated with syntax, showed minimal effects of sentence structure. The ATL, PTL and IFG all showed effects of semantic content: increased activation for real words relative to nonwords. Our fMRI‐guided MEG investigation therefore helps identify syntactic and semantic aspects of sentence comprehension in the brain in both spatial and temporal dimensions.

“…While the studies comparing sentences with word lists have provided valuable understandings of the neural basis of sentence processing, they were inevitably confounded due to the fact that the word lists often comprised a mixture of function and content words (Friederici, ). As a result, some basic syntactic combinations were still plausible in the word lists and thus the true effect of syntactic computation may be concealed in the comparison between the sentences and word lists (Zaccarella, Schell, & Friederici, ). The studies using minimal phrase structures, on the contrary, have been suggested to eliminate such confounding by minimizing the word lists to two or three words from the same category (Schell et al, ; Zaccarella & Friederici, ).…”

Section: Introductionmentioning

confidence: 99%

Universal neural basis of structure building evidenced by network modulations emerging from Broca's area: The case of Chinese

Zaccarella

Friederici

2018

Self Cite

The basic steps in building up language involve binding words of different categories into a hierarchical structure. To what extent these steps are universal or differ across languages is an open issue. Here we examine the neural dynamics of phrase structure building in Chinese—a language that in contrast to other languages heavily depends on contextual semantic information. We used functional magnetic resonance imaging and dynamic causal modeling to identify the relevant brain regions and their dynamic relations. Language stimuli consisted of syntax‐driving determiners, semantics‐embedded classifiers, and nonverbal symbols making up for two‐component sequences manipulated by the factors structure (phrase/list) and number of words (2‐word/1‐word). Processing phrases compared with word lists elicited greater activation in the anterior part of Broca's area, Brodmann area (BA) 45, and the left posterior superior/middle temporal gyri (pSTG/pMTG), while processing two words against one word led to stronger involvement of the left BA 45, BA 44, and insula. Differential network modulations emerging from subparts of Broca's area revealed that phrasal construction in particular highly modulated the direct connection from BA 44 to left pMTG, suggesting BA 44’s primary role in phrase structure building. Conversely, the involvement of BA 45 rather appears sensitive to the reliance on lexico‐semantic information in Chinese. Against the background of previous findings from other languages, the present results indicate that phrase structure building has a universal neural basis within the left fronto‐temporal network. Most importantly, they provide the first evidence demonstrating that the structure‐building network may be modulated by language‐specific characteristics.