Neural substrates of word category information as the basis of syntactic processing

Abstract

The ability to use word category information (WCI) for syntactic structure building has been hypothesized to be the essence of human language faculty. The neural substrate of the ability of using the WCI for the complex syntactic hierarchical structure processing, however, is yet unknown. Therefore, we directly conducted an fMRI experiment by using a pseudo‐Chinese artificial language with syntactic structures containing a center‐embedded relative clause. Thirty non‐Chinese native (Korean) speakers were randomly divided into two groups: one acquired WCI and WCI‐based syntactic rules (the WCI group) before the scanning session, and the other did not (the non‐WCI group). Both groups were required to judge the grammaticality of the testing sentences, with critical long‐distance dependencies between two elements (the main verb and the relativizer). Behaviorally, the WCI group's accuracy was significantly higher and its reaction time was shorter. The scanning results showed that the left superior temporal gyrus (STG) and Broca's area were more strongly activated for the WCI group, and the dynamic causal modeling analyses revealed a distinct effective connectivity pattern for this group. Therefore, the present research, for the first time, reveals that the activation of and the functional connectivity between Broca's area and the left STG play a critical role in the ability of the rule‐based use of the WCI which is crucial for complex hierarchical structure building, and might be substantially corresponding to the “labeling competence” within the linguistic framework.

When a sentence loses semantics: Selective involvement of a left anterior temporal subregion in semantic processing

“…As the SPH stimuli allowed predictions about incoming elements based exclusively on syntactic information, the activation for the contrast of SPH > NAT may have reflected syntactic predictions. This is in line with recent studies reporting associations between language‐related regions, such as Broca's area, and syntactic prediction (Bonhage et al., 2015; Chen et al., 2019; Shain et al., 2020; Söderström et al., 2018). However, we acknowledge that there are two potential confounding factors for the contrast of SPH > NAT.…”

Syntax through the looking glass: A review on two-word linguistic processing across behavioral, neuroimaging and neurostimulation studies

“…This is further supported by recent studies showing that the left IFG (Trettenbrein et al, 2020) and the posterior temporal lobe (Matchin et al, 2022) are central regions in processing signed languages, in line with the abstract nature of their linguistic operations. Similarly, recent evidence from artificial grammar paradigms supports the involvement of the left IFG and PTL in abstract categorical processes (Chen et al, 2021;Chen et al, 2019), putting forward the working hypothesis that dissociations between left IFG and pTL in syntactic composition can be traced-the left IFG being specialized in building up hierarchies on the basis of categorical features, the PTL integrating hierarchies with other sources of linguistic information, including meaning. Under this account, the information exchange between the left IFG and PTL would allow to reconstruct the hierarchical dependencies characterizing human language, providing an analysis that will also interface with the semantic system.…”

Hierarchical syntactic processing is beyond mere associating: Functional magnetic resonance imaging evidence from a novel artificial grammar

“…For example, the determiner “[ D the]” and the noun “[ N apple]” together form the determiner phrase “[ DP the apple],” which can further combine with the verb “[ V eat]” to form the verbal phrase “[ VP eat the apple]” as a larger constituent (see Figure 1a). The capacity to create hierarchical structures out of syntactic category relations has been deemed fundamental for language processing as a unique human language trait (Chen et al, 2019; Fujita, 2014; Berwick et al, 2013; Friederici, 2019; Goucha, Zaccarella, & Friederici, 2017; Miyagawa et al, 2013). In the current study, we approach the fundamental question of how the human brain imposes hierarchical syntactic structures on linearized word sequences (i.e., hierarchical syntactic processing) on the basis of the syntactic category relations by using an artificial grammar learning/processing paradigm.…”