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Available online 24 March 2021 Semantic prediction and cortical entrainment to the acoustic landmarks of the speech envelope are two fundamental yet qualitatively different mechanisms that facilitate speech comprehension. However, it is not clear how and to what extent those mechanisms interact with each other. On the one hand, richer semantic context could enhance the perceptual representation of a predictable stimulus, thus improving speech entrainment. On the other hand, pre-activating an upcoming item could inhibit further bottom-up analyses to minimize processing costs, thus weakening speech entrainment. To test these competing hypotheses, we recorded EEG activity from 27 participants while they listened to a 14-min recording of text reading. The passage contained target words presented twice: once in a highly constraining and once in a minimally constraining context. First, we measured event related potentials on target words in the two conditions. In line with previous research, we showed that semantic predictability modulated the N400 amplitude: words in minimally constraining contexts elicited larger negative amplitudes than words in highly constraining contexts between 250 and 450 ms. Second, we evaluated speech entrainment effects by analyzing phase alignment between neural activity and the envelope of target words. Importantly, we found increased speech entrainment for words in minimally constraining compared to highly constraining contexts between 400 and 450 ms. Both effects were located in central electrodes and were significantly correlated. Our results indicate a trade-off between semantic pre-activation and cortical entrainment to speech and support the cost minimization hypothesis. The present study was supported by the Spanish Ministry of Science, Innovation and Universities (grant RTI2018-096311-B-I00 to Nicola Molinaro; grants RTI2018-096242-B-I00 and RYC-2015-17356 to Marie Lallier), the Agencia Estatal de Investigaci´on (AEI), the Fondo Europeo de Desarrollo Regional (FEDER). The authors acknowledge financial support from the Basque Government through the BERC 2018–2021 program, by the Spanish State Research Agency through BCBL Severo Ochoa excellence accreditation SEV-2015-0490.

Unagreement patterns consist in a person feature mismatch between subject and verb that is nonetheless grammatical in Spanish. The processing of this type of construction gives new insights into the understanding of agreement processes during language comprehension. Here, we contrasted oscillatory brain activity triggered by Unagreement in different EEG bands with those triggered by Standard Agreement and Person Mismatch sentences. In Spectral Power analysis, a similar pattern for Unagreement to that elicited by Person Mismatch was found in lower beta and alpha bands, approximately around 600 ms. This suggests that fast oscillations reflect the evaluation of the feature match between two structurally related constituents (independently of its grammaticality). In an equivalent time window, the Unagreement condition behaves similarly to the Standard Agreement condition in the theta band, but different from the Person Mismatch condition that shows an enhanced spectral power. In addition, an enhanced phase synchrony in lower beta frequency around 600 ms is associated to standard agreement patterns, while beta-high frequencies at 800 ms characterize processing of Unagreement sentences. These results support the functional dissociation between the evaluation of the feature match between two structurally related constituents (independently of its grammaticality—in fast oscillatory bands) and integration of linguistic material in working memory (reflected by theta oscillations). Successful resolution of an agreement dependency is better reflected in phase synchronizations at beta band.

Word reading in alphabetic languages involves letter identification, independently of the format in which these letters are written. This process of letter ‘regularization’ is sensitive to word context, leading to the recognition of a word even when numbers that resemble letters are inserted among other real letters (e.g., M4TERI4L ). The present study investigates the electrophysiological correlates of number-to-letter regularization by means of the masked priming paradigm: target words ( MATERIAL ) were preceded by fully alphabetic primes ( MATERIAL ), primes with letter-like numbers ( M4T3R14L ), or primes with unrelated numbers ( M7T6R28L ). ERPs revealed three subsequent effects. Around 150 ms the unrelated numbers condition elicited a positive effect, compared to the other two conditions, in the occipital electrodes. Then, target words preceded by primes with numbers elicited a more negative N200 in the same electrodes compared to the fully alphabetic condition. Finally, both alphabetic primes and letter-like numbers elicited a posterior positive component peaking around 260 ms compared to unrelated numbers. Source analysis for each electrophysiological effect revealed a similar early increase of activity in the left occipito-temporal pathway for alphabetic primes and primes with letter-like numbers. Around 200 ms, the orthographic interference due to the numerical values correlated with an increase of activity in parietal areas; finally, a recursive effect in the left occipital cortex was found, reflecting abstract letter activation. These results indicate that direct feedback interaction from word units strongly influences the activation of the letter units at a format-independent abstract level.

Whether the neural mechanisms that underlie the processing of a second language in highly proficient late bilinguals (L2 late learners) are similar or not to those that underlie the processing of the first language (L1) is still an issue under debate. In this study, a group of late learners of Spanish whose native language is English and a group of Spanish monolinguals were compared while they read sentences, some of which contained syntactic violations. A brain complex network analysis approach was used to assess the time-varying topological properties of the functional networks extracted from the electroencephalography (EEG) recording. Late L2 learners showed a lower degree of parallel information transfer and a slower propagation between regions of the brain functional networks while processing sentences containing a gender mismatch condition as compared with a standard sentence configuration. In contrast, no such differences between these conditions were detected in the Spanish monolinguals. This indicates that when a morphosyntactic language incongruence that does not exist in the native language is presented in the second language, the neural activation pattern is configured differently in highly proficient late bilinguals than in monolinguals.