Brain and Language最新文献

Previous EEG studies demonstrated ample evidence for a major influence of morphological regularity on inflectional processing. However, regularity effects may be attributed to different properties of inflectional classes: to type frequency, to productivity, or to defaultness (assumed only in some models). In many languages, these factors cannot be teased apart, but it is possible in Russian. Several previous behavioural and fMRI studies claimed that one of the five productive inflectional verb classes shows the properties of the default. Relying on these works, we conducted an EEG study on Russian that involved a verb form selection task. We analysed ERPs and time-frequency responses to verbs from three inflectional classes and to pseudoverbs matching their relevant properties. We observed distinct time-frequency effects of defaultness and productivity. Default class verbs elicited broadband power modulations in different regions, which can be associated with working memory activity during the preparation for verb form selection. Productive class verbs modulated theta and beta power during verb form selection. Additionally, distinct time-frequency and ERP responses to real vs. pseudoverbs were observed during the whole task. These results speak for the special status of the default inflectional class in the inflectional system.

The rapid turn-taking in conversation requires accurately predicting and planning the timing of turns (Levinson & Torreira, 2015). However, most previous studies have focused on predicting others' turn-ends, neglecting the self-initiated processes of turn-taking. Additionally, there is limited neural evidence on how prosodic context influences turn-end prediction. This study examined neural responses concerning both turn-end prediction and turn-planning in an EEG experiment. We used cross-splicing to generate sentences with varying prosodic contexts and lengths so that participants could not anticipate turn-ends using sentence length. Participants listened to a requesting statement and verbally responded with the requested item upon hearing a beep, which either matched or mismatched the turn-end indicated by the prosodic context, rendering a 2 (prosodic context) by 2 (beep-context congruence) design. Results showed that the beep sound elicited a more negative N2 amplitude and less positive P3 amplitude under incongruent relative to congruent conditions and reduced late positivity (LP) under long versus short prosodic contexts. Single-trial analyses revealed that a smaller amplitude of LP was associated with longer reaction time (RT) regardless of prosodic context. Prosodic context moderated the relationship between P3 amplitude and RT, showing a positive correlation under short prosodic contexts but no correlation under long prosodic contexts. These findings suggest that participants use prosodic context to predict upcoming turn-ends, aiding in planning their responses. Listeners likely combine event-based cues (e.g., beep) and interval-based cues (e.g., prosody) to build temporal speech structures, which are processed by a dual-pathway neurocognitive system underlying temporal prediction.

Embodied semantics proposes that language comprehension involves sensorimotor reactivations, yet the extent of this in olfactory language remains unclear, particularly for Chinese metaphorical expressions. This study investigated the neural mechanisms of literal and metaphorical olfactory language processing in Chinese. Twenty-four native Mandarin speakers underwent fMRI scanning while silently reading sentences with literal and metaphorical olfactory meanings. Whole-brain and ROI analyses revealed that literal olfactory sentences elicited robust activation in the left inferior frontal gyrus, pars orbitalis, whereas olfactory metaphors did not. This dissociation persisted, although in attenuated form, when sentence-level familiarity was controlled. Olfactory threshold scores correlated positively with right piriform cortex activity during literal sentence processing. We also observed a posterior-to-anterior neural shift from concrete to abstract representations in the olfactory context. Finally, verb- and adjective-based olfactory metaphors appeared to rely on a shared neural system, with limited influence of grammatical class. Taken together, our results support the Embodied Abstraction Account, which emphasizes the flexible, context-dependent nature of conceptual representation, and challenge the Strong Embodiment Theory.