Search

First published: 27 February 2023 The coordination between the theta phase (3–7 Hz) and gamma power (25–35 Hz) oscillations (namely theta-gamma phase-amplitude coupling, PAC) in the auditory cortex has been proposed as an essential neural mechanism involved in speech processing. However, it has not been established how this mechanism is related to the efficiency with which a listener processes speech. Speech processing in a non-native language offers a useful opportunity to evaluate if theta-gamma PAC is modulated by the challenges imposed by the reception of speech input in a non-native language. The present study investigates how auditory theta-gamma PAC (recorded with magnetoencephalography) is modulated in both native and non-native speech reception. Participants were Spanish native (L1) speakers studying Basque (L2) at three different levels: beginner (Grade 1), intermediate (Grade 2), and advanced (Grade 3). We found that during L2 speech processing (i) theta-gamma PAC was more highly coordinated for intelligible compared to unintelligible speech; (ii) this coupling was modulated by proficiency in Basque being lower for beginners, higher for intermediate, and highest for advanced speakers (no difference observed in Spanish); (iii) gamma power did not differ between languages and groups. These findings highlight how the coordinated theta-gamma oscillatory activity is tightly related to speech comprehension: the stronger this coordination is, the more the comprehension system will proficiently parse the incoming speech input. This research is supported by the Basque Government through the BERC 2022-2025 program, the Spanish State Research Agency through BCBL Severo Ochoa excellence accreditation CEX2020- 001010-S, the Spanish Ministry of Science, Innovation and Universities (IJC2020-042886-I to M.L.; PID2021-122918OB-I00 to M.C; RTI2018-096311-B-I00 and PCI2022-135031-2 to N.M.;) and the IKUR #neural2speech project

Perceptual systems heavily rely on prior knowledge and predictions to make sense of the environment. Predictions can originate from multiple sources of information, including contextual short-term priors, based on isolated temporal situations, and context-independent long-term priors, arising from extended exposure to statistical regularities. While short-term predictions have been well-documented, long-term predictions have received limited support, especially in the auditory domain. To address this, we recorded magnetoencephalography data from native speakers of two languages with different word orders (Spanish: functor-initial versus Basque: functor-final) listening to simple sequences of binary sounds alternating in duration with occasional omissions. We hypothesized that, together with contextual transition probabilities, the auditory system uses the characteristic prosodic cues (duration) associated with the native language’s word order as an internal model to generate long-term predictions about incoming non-linguistic sounds. Consistent with our hypothesis, we found that the amplitude of the mismatch negativity elicited by sound omissions varied orthogonally depending on the speaker’s linguistic background and was most pronounced in the left auditory cortex. Importantly, listening to binary sounds alternating in pitch instead of duration did not yield group differences, confirming that the above results were driven by the hypothesized long-term “duration” prior. These findings show that experience with a given language can shape a fundamental aspect of human perception – the neural processing of rhythmic sounds – and provides direct evidence for a long-term predictive coding system in the auditory cortex that uses auditory schemes learned over a lifetime to process incoming sound sequences.

Is language selection decodable from neural activity in balanced bilinguals? Previous research employing various neuroimaging methods has not yielded a conclusive answer to this issue. However, direct brain stimulation studies in bilinguals have detected different brain regions related to language production in separate languages. In the present MEG study, we addressed this question in a group of proficient Spanish-Basque bilinguals (N=45), who performed two tasks. In a picture naming task, they were asked to name a picture either in Basque or in Spanish if the ink turned from black to green after one second (10% of trials). Similarly, in a word reading task, participants read printed words out loud only when the ink turned to green. Sensor-level evoked activity was similar for the two languages on both tasks. However, decoding analyses classified the language used in both tasks, starting ~100 ms after stimulus onset. Crucially, searchlight analyses revealed that the right occipital-temporal sensors contributed most to language decoding in the picture naming task, while the left occipital-temporal sensors contributed most to decoding in word reading. Temporal generalization analyses for the picture naming task showed a sustained effect, while for the word reading task two stages of processing (at ~100 ms and starting ~300 ms) were evident. Cross-task decoding analysis highlighted robust generalization effects from the picture naming to the word reading task in the later time interval. The present findings provide support for the possibility of exploring the trial-by-trail variability in MEG activity for dissociating languages in the bilingual brain. For the first time, we provide evidence for a differential role of the two hemispheres in language selection for picture naming and word reading. We also provide novel evidence on the shared language representations between naming and word reading.

Numbers and letters are the fundamental building blocks of our everyday social interactions. Previous studies have focused on determining the cortical networks shaped by numeracy and literacy in the human brain, partially supporting the hypothesis of distinct neural circuits involved the processing of the two categories. In this study, we aim to investigate the temporal dynamics for number and letter processing. We present MEG data from two experiments (N=20 each). In the first experiment, single numbers, letter, and their respective false fonts (false numbers and false letters) were presented, whereas, in the second experiment, numbers, letters, and their respective false fonts were presented as a string of characters. We used multivariate pattern analysis techniques (time-resolved decoding and temporal generalization) testing the strong hypothesis that the neural mechanisms supporting letter and number processing can be logistically classified as categorically separate. Our results show a very early dissociation (∼100 ms) between numbers, and letters when compared to false fonts. Number processing can be dissociated with similar accuracy when presented as isolated items or strings of characters, while letter processing shows dissociable classification accuracy for single items compared to strings. These findings reinforce the evidence indicating that early visual processing can be differently shaped by the experience with numbers and letters; this dissociation is stronger for strings compared to single items, thus showing that combinatorial mechanisms for numbers and letters could be categorically distinguished and influence early brain activity.

It is well established that early bilinguals who speak languages that differ in the phonetic implementation of the voicing contrast have language-specific voicing systems. This study investigates voicing separation in bilinguals who speak two true-voicing languages, Basque and Spanish. We also describe the voicing system in Gipuzkoan Spanish and Gipuzkoan Basque, which is the closest dialect to Standard Basque and it has not yet been investigated experimentally. Twenty Basque-Spanish early bilingual speakers of Gipuzkoan dialects participated in two picture naming tasks. We described their voicing system by measuring voice onset time (VOT) in both Gipuzkoan Basque and Spanish, and used linear mixed-effects models to investigate between-language production differences. Our results show for the first time that adult early bilinguals who speak two true-voicing languages produce language-specific VOT in ‘voiced’ plosives. This finding demonstrates that bilinguals’ phonetic systems during production are more fine-grained than previously assumed, and contributes to a deeper understanding of granularity in early bilingual phonetic systems.

Published Jun 2022 Although research in sentence comprehension has suggested that processing long-distance dependencies involves maintenance between the elements that form the dependency, studies on maintenance of long-distance subject–verb (SV) dependencies are scarce. The few relevant studies have delivered mixed results using self-paced reading or phoneme-monitoring tasks. In the current study, we used eye tracking during reading to test whether maintaining a long-distance SV dependency results in a processing cost on an intervening adverbial clause. In Experiment 1, we studied this question in Spanish and found that both go-past reading times and regressions out of an adverbial clause to the previous regions were significantly increased when the clause interrupts a SV dependency compared to when the same clause doesn’t interrupt this dependency. We then replicated these findings in English (Experiment 2), observing significantly increased go-past reading times on a clause interrupting a SV dependency. The current study provides the first eye-tracking data showing a maintenance cost in the processing of SV dependencies cross-linguistically. Sentence comprehension models should account for the maintenance cost generated by SV dependency processing, and future research should focus on the nature of the maintained representation. This research was partially funded by Ministerio de Economía y Competitividad, Agencia Estatal de Investigación & Fondo Europeo de Desarrollo Regional Grants PSI2015-65694-P, and RTI2018-096311-B-I00 to Nicola Molinaro, and RYC-2017–22015 and FFI2016-76432-P_LAMPT to Simona Mancini; by Eusko Jaurlaritza Grants PI_2016_1_0014 to Nicola Molinaro, PRE_2018_2_0074 and EP_2018_1_0042 to Bojana Ristic; and by Agencia Estatal de Investigación’s Severo Ochoa excellence program Grant SEV2015– 0490 to the Basque Center on Cognition, Brain and Language.

Cortical tracking of linguistic structures in speech, such as phrases (, info:eu-repo/semantics/published

Published online: 04 Oct 2021 Neural entrainment to the low-frequency modulations of speech might contribute significantly to reading acquisition. Still, no previous study has actually attempted to establish a longitudinal link between them. The present study tested Basque-speaking children twice: once before reading was formally instructed (t1; 5–6 years old) and once after they had received a full school year of reading instruction (t2; 6–7 years old). At t1, speech-brain coherence was recorded via EEG. At t2, in addition to the coherence measure, reading performance was assessed. Our results show that children with larger pre-reading delta-band (

Hearing spoken words can enhance visual object recognition, detection and discrimination. Yet, the mechanisms that underpin this facilitation are incompletely understood. On one account, words do not bias early visual processing, but rather affect later semantic or decision-making stages. However, recent proposals suggest that words can alter early visual processes by activating category-specific priors in sensory regions. A prediction of this account is that top-down priors evoke changes in occipital areas in anticipation of visual stimuli. Here, we tested the hypothesis that neural oscillations serve as a mechanism to activate language-generated visual priors. Participants performed a cue-picture matching task where cues were either spoken words, in their native or second language, or natural sounds, while their EEG and reaction times were recorded. Behaviorally, we replicated the previously reported label-advantage effect, with images cued by words being recognized faster than those cued by natural sounds. A time-frequency analysis of cue-target intervals revealed that this behavioral label-advantage was associated with enhanced power in posterior alpha (9-11 Hz) and beta oscillations (17-19 Hz), both of which were larger when the image was preceded by a word compared to a natural sound. Importantly, object recognition performance improved with high alpha power but slowed down with enhancement of beta synchronization. These results suggest that alpha and beta rhythms play distinct functional roles to support language-mediated visual object recognition: alpha might function to amplify sensory priors in posterior regions, while beta may (re)activate the network states elicited by the auditory cue.

Published online: 23 May 2019. We investigated how listeners use gender-marked adjectives to adjust lexical predictions during sentence comprehension. Participants listened to sentence fragments in Spanish (e.g. “The witch flew to the village on her…”) that created expectation for a specific noun (broomstickfem), and were completed by an adjective and a noun. The adjective either agreed (newfem), disagreed (newmasc), or was neutral (bigfem/masc) with respect to the expected noun’s gender. Using the visual-world paradigm, we monitored looks toward images of the expected noun versus an alternative of the opposite gender (helicoptermasc). While listening to the initial fragment, participants looked more towards the expected noun. Once the adjective was heard, looks shifted toward the noun that matched the adjective’s gender. Finally, upon hearing the noun, looks were affected by both previous context and adjective gender. We conclude that predictions are updated online based on gender cues, but sentence context still affects integration of the expected noun. This work was partially supported by the Ministerio de Economía, Industria y Competitividad, Gobierno de España, the Agencia Estatal de Investigación and the Fondo Europeo de Desarrollo Regional (grant PSI2015-65694-P, “Severo Ochoa” programme SEV-2015-490 for Centres of Excellence in R&D), and by the Eusko Jaurlaritza (grant PI_2016_1_0014). Further support derived from the AThEME project funded by the European Commission Seventh Framework Programme, the ERC- 2011-ADG-295362 from the European Research Council. This project was also supported by the Ministerio de Economía, Industria y Competitividad, Gobierno de España through the convocatoria 2016 Subprograma Estatal Ayudas para contratos para la Formación Posdoctoral 2016, Programa Estatal de Promoción del Talento y su Empleabilidad del Plan Estatal de Investigación Científica y Técnica y de Innovación 2013–2016, reference FJCI-2016-28019.

The main objective of our studies is to understand the neural bases underlying phonological difficulties in dyslexia. First, we will review the theoretical research framework generated around the phonological theory of dyslexia. Second, we will review what are the neural mechanisms involved in the segmentation of speech in control readers. In this section we will demonstrate that the synchronization between speech rhythms and neural oscillations at different frequency bands plays a key role in the segmentation of speech. Next, we will present different studies that suggest that dyslexic readers present a desynchronization between speech rhythms and neuronal oscillations in auditory regions. This lack of synchronization could cause the auditory perception problems and the phonological difficulties that we observe in readers with dyslexia. Finally, we will present recent studies from our laboratory that support the theory of neuronal desynchronization in dyslexia and show that these problems are also present in children with dyslexia.

The ability to establish associations between visual objects and speech sounds is essential for human reading. Understanding the neural adjustments required for acquisition of these arbitrary audiovisual associations can shed light on fundamental reading mechanisms and help reveal how literacy builds on pre-existing brain circuits. To address these questions, the present longitudinal and cross-sectional MEG studies characterize the temporal and spatial neural correlates of audiovisual syllable congruency in children (4-9 years old, 22 males and 20 females) learning to read. Both studies showed that during the first years of reading instruction children gradually set up audiovisual correspondences between letters and speech sounds, which can be detected within the first 400 ms of a bimodal presentation and recruit the superior portions of the left temporal cortex. These findings suggest that children progressively change the way they treat audiovisual syllables as a function of their reading experience. This reading-specific brain plasticity implies (partial) recruitment of pre-existing brain circuits for audiovisual analysis.Significance StatementLinking visual and auditory linguistic representations is the basis for the development of efficient reading, while dysfunctional audiovisual letter processing predicts future reading disorders. Our developmental MEG project included a longitudinal and a cross-sectional study; both studies showed that children’s audiovisual brain circuits progressively change as a function of reading experience. They also revealed an exceptional degree of neuroplasticity in audiovisual neural networks, showing that as children develop literacy, the brain progressively adapts so as to better detect new correspondences between letters and speech sounds.

Emotion processing has been a focus of research in psychology and neuroscience for some decades. While the evoked neural markers in human brain activations in response to different emotions have been reported, the temporal dynamics of emotion processing has received less attention. Differences in processing speeds, that depend on emotion type, have not been determined. Furthermore, behavioral studies have found that the right side of the human face expresses emotions more accurately than the left side. Therefore, accounting for both the content of the emotion and the visual angle of presentation from the perspective of the viewer, here we have investigated variability in the discrimination of happy and sad faces when the visual angle of presentation was Positive (right side of the face) compared to Negative (left side of the face). Furthermore, the temporal dynamics involved in processing happy and sad emotions have been compared. Regardless of visual angle, happy emotions were processed faster than sad emotions. However, the evoked response to sad emotions significantly increased in amplitude compared to that for happy emotions, when faces were presented at Positive visual angles only. Source reconstruction from sensor-level ERFs show localized activities in ventral and dorsal stream, including fusiform gyrus, lingual gyrus, putamen and Pre and Post central gyrus. Multivariate pattern analysis (MVPA) confirmed these findings – demonstrating successful decoding of happy and sad emotions only occurred when the facial expression was viewed from a positive visual angle, and that happy emotions were processed faster than sad emotions.

Neurofeedback represents a particular type of biofeedback whose aim is to teach self-control of brain function by measuring brain activity and presenting a feedback signal in real-time. Traditionally, neurofeedback has been used to complement interventions for various neuropsychological disorders through techniques like frequency training, which attempts to change the power ratio of certain EEG frequency bands. However, to date, there are no neurofeedback approaches that look directly into modulating the neural entrainment to speech. Speech-brain entrainment, which stands for the alignment of the neural activity to the envelope of the speech input, has been shown to be key to speech comprehension. In fact, atypical neural entrainment to speech seems to be consistently found in language development disorders such as dyslexia. Thus, making speech entrainment neurofeedback a promising technique to obtain behavioral improvements. In this work, we present the first open-source brain-computer interface system that can be reliably used to provide speech entrainment neurofeedback while still being flexible enough to deliver more traditional coherence-based neurofeedback. In addition, it has the potential of being an open-source alternative to deliver other types of neurofeedback if configured to do so.

First published: 24 December 2020 Recent evidence suggests that damage to the language network triggers its functional reorganization. Yet, the spectro-temporal fingerprints of this plastic rearrangement and its relation to anatomical changes is less well understood. Here, we combined magnetoencephalographic recordings with a proxy measure of white matter to investigate oscillatory activity supporting language plasticity and its relation to structural reshaping. First, cortical dynamics were acquired in a group of healthy controls during object and action naming. Results showed segregated beta (13–28 Hz) power decreases in left ventral and dorsal pathways, in a time-window associated to lexico-semantic processing ( 250–500 ms). Six patients with left tumors invading either ventral or dorsal regions performed the same naming task before and 3 months after surgery for tumor resection. When longitudinally comparing patients' responses we found beta compensation mimicking the category-based segregation showed by controls, with ventral and dorsal damage leading to selective compensation for object and action naming, respectively. At the structural level, all patients showed preoperative changes in white matter tracts possibly linked to plasticity triggered by tumor growth. Furthermore, in some patients, structural changes were also evident after surgery and showed associations with longitudinal changes in beta power lateralization toward the contralesional hemisphere. Overall, our findings support the existence of anatomo-functional dependencies in language reorganization and highlight the potential role of oscillatory markers in tracking longitudinal plasticity in brain tumor patients. By doing so, they provide valuable information for mapping preoperative and postoperative neural reshaping and plan surgical strategies to preserve language function and patient's quality of life. Basque Government, Grant/Award Number: BERC 2018-2021; Spanish Ministry of Economy and Competitiveness, Grant/Award Number: RTI2018-096216-A-I00 (MEGLIOMA) and RTI2018-093547-B-I00 (LangConn); Spanish State Research Agency, Grant/Award Number: SEV-2015-0490 and IJCI-2017-31373

Contextual information triggers predictions about the content (“what”) of environmental stimuli to update an internal generative model of the surrounding world. However, visual information dynamically changes across time, and temporal predictability (“when”) may influence the impact of internal predictions on visual processing. In this magnetoencephalography (MEG) study, we investigated how processing feature specific information (“what”) is affected by temporal predictability (“when”). Participants (N = 16) were presented with four consecutive Gabor patches (entrainers) with constant spatial frequency but with variable orientation and temporal onset. A fifth target Gabor was presented after a longer delay and with higher or lower spatial frequency that participants had to judge. We compared the neural responses to entrainers where the Gabor orientation could, or could not be temporally predicted along the entrainer sequence, and with inter-entrainer timing that was constant (predictable), or variable (unpredictable). We observed suppression of evoked neural responses in the visual cortex for predictable stimuli. Interestingly, we found that temporal uncertainty increased expectation suppression. This suggests that in temporally uncertain scenarios the neurocognitive system invests less resources in integrating bottom-up information. Multivariate pattern analysis showed that predictable visual features could be decoded from neural responses. Temporal uncertainty did not affect decoding accuracy for early visual responses, with the feature specificity of early visual neural activity preserved across conditions. However, decoding accuracy was less sustained over time for temporally jittered than for isochronous predictable visual stimuli. These findings converge to suggest that the cognitive system processes visual features of temporally predictable stimuli in higher detail, while processing temporally uncertain stimuli may rely more heavily on abstract internal expectations., SCOPUS: ar.j, info:eu-repo/semantics/published

Speech comprehension has been proposed to critically rely on oscillatory cortical tracking, that is, phase alignment of neural oscillations to the slow temporal modulations (envelope) of speech. Speech-brain entrainment is readjusted over time as transient events (edges) in speech lead to speech-brain phase realignment. Auditory behavioral research suggests that phonological deficits in dyslexia are linked to difficulty in discriminating speech edges. Importantly, research to date has not specifically examined neural responses to speech edges in dyslexia. In the present study, we used MEG to record brain activity from normal and dyslexic readers while they listened to speech. We computed phase locking values (PLVs) to evaluate phase entrainment between neural oscillations and the speech envelope time-locked to edge onsets. In both groups, we observed that edge onsets induced phase resets in the auditory oscillations tracking speech, thereby enhancing their entrainment to speech. Importantly, dyslexic readers showed weaker PLVs compared to normal readers in left auditory regions from ~.15 sec to ~.65 sec after edge onset. Our results indicate that the neural mechanism that adapts cortical entrainment to the speech envelope is impaired in dyslexia. These findings here are consistent with the temporal sampling theory of developmental dyslexia., SCOPUS: ar.j, info:eu-repo/semantics/published

Published:07 April 2021 Cortical circuits rely on the temporal regularities of speech to optimize signal parsing for sound-to-meaning mapping. Bottom-up speech analysis is accelerated by top–down predictions about upcoming words. In everyday communications, however, listeners are regularly presented with challenging input—fluctuations of speech rate or semantic content. In this study, we asked how reducing speech temporal regularity affects its processing—parsing, phonological analysis, and ability to generate context-based predictions. To ensure that spoken sentences were natural and approximated semantic constraints of spontaneous speech we built a neural network to select stimuli from large corpora. We analyzed brain activity recorded with magnetoencephalography during sentence listening using evoked responses, speech-to-brain synchronization and representational similarity analysis. For normal speech theta band (6.5–8 Hz) speech-to-brain synchronization was increased and the left fronto-temporal areas generated stronger contextual predictions. The reverse was true for temporally irregular speech—weaker theta synchronization and reduced top–down effects. Interestingly, delta-band (0.5 Hz) speech tracking was greater when contextual/semantic predictions were lower or if speech was temporally jittered. We conclude that speech temporal regularity is relevant for (theta) syllabic tracking and robust semantic predictions while the joint support of temporal and contextual predictability reduces word and phrase-level cortical tracking (delta). The European Union’s Horizon 2020 research and innovation programme (under the Marie Sklodowska-Curie grant agreement No 798971 awarded to A.K.G.); the Spanish Ministry of Science, Innovation and Universities (grant RTI2018-096311-B-I00 to N.M.); the Agencia Estatal de Investigación (AEI), the Fondo Europeo de Desarrollo Regional (FEDER); the Basque Government (through the BERC 2018-2021 program), the Spanish State Research Agency through BCBL Severo Ochoa excellence accreditation (SEV-2015-0490), DeepText project (KK-2020/00088) and Ixa excellence research group (IT1343-19). the UPV/EHU (a postdoctoral grant ESPDOC18/101 to A.B.); the NVIDIA Corporation (to A.B. with the donation of a Titan V GPU used for this research).

Predictive processing has been proposed as a fundamental cognitive mechanism to account for how the brain interacts with the external environment via its sensory systems. In vision, contextual information triggers predictions about the content (“what”) of environmental stimuli to update an internal generative model of the surrounding world. However, visual information dynamically changes across time, and temporal predictability (“when”) may influence the impact of internal predictions on visual processing. In this magnetoencephalography (MEG) study, we investigated how processing feature specific information (“what”) is affected by temporal predictability (“when”). In line with previous findings, we observed suppression of evoked neural responses in the visual cortex for predictable stimuli. Interestingly, we found that temporal uncertainty increased expectation suppression. This suggests that in temporally uncertain scenarios the neurocognitive system invests less resources in integrating bottom-up information. Multivariate pattern analysis showed that predictable visual features could be decoded from neural responses. Temporal uncertainty did not affect decoding accuracy for early visual responses, with the feature specificity of early visual neural activity preserved across conditions. However, decoding accuracy was less sustained over time for temporally jittered than for isochronous predictable visual stimuli. These findings converge to suggest that the cognitive system processes visual features of temporally predictable stimuli in higher detail, while processing temporally uncertain stimuli may rely more heavily on abstract internal expectations.

How the human brain uses self-generated auditory information during speech production is rather unsettled. Current theories of language production consider a feedback monitoring system that monitors the auditory consequences of speech output and an internal monitoring system, which makes predictions about the auditory consequences of speech before its production. To gain novel insights into underlying neural processes, we investigated the coupling between neuromagnetic activity and the temporal envelope of the heard speech sounds (i.e. cortical tracking of speech) in a group of adults who 1) read a text aloud, 2) listened to a recording of their own speech (i.e. playback), and 3) listened to another speech recording. Reading aloud was here used as a particular form of speech production that shares various processes with natural speech. During reading aloud, the reader's brain tracked the slow temporal fluctuations of the speech output. Specifically, auditory cortices tracked phrases (, SCOPUS: ar.j, info:eu-repo/semantics/published

Language comprehension relies on the fundamental ability to create meaningful syntactic structures from single words during on-line processing. Time-resolved neuroimaging techniques can be used to measure electrophysiological activity revealing the neural dynamics underpinning these combinatorial processes in the brain. In the present chapter, we review and critically evaluate studies that have specifically investigated the electrophysiological bases of sentence-level syntactic processing using different types of analyses and paradigms. Besides reviewing event-related potential (ERP) studies, we focus on recent investigations of neural oscillations, highlighting their relevance and implications for our understanding of syntactic processing. Furthermore, we discuss critical issues related to the interpretation of current electrophysiological findings, including open questions such as the relationship between syntax and semantics and the link between ERPs and oscillations.

Assessing the synchrony and interplay between distributed neural regions is critical to understanding how language is processed. Here, we investigated possible neuro-functional links between form and meaning during sentence comprehension combining a classical whole-brain approach, which characterizes patterns of brain activation resulting from our experimental manipulation, and a novel multivariate network-based approach, which uses graph-theory measures to unravel the architectural configuration of the language system. Capitalizing on the Spanish gender agreement system, we experimentally manipulated formal and conceptual factors: whether the noun-adjective grammatical gender relationship was congruent or not and whether the noun gender type was semantically informative or strictly formal. Left inferior and middle frontal gyri, as well as left MTG/STG emerged as critical areas for the computation of grammatical relations. We demonstrate how the interface between formal and conceptual features depends on the synergic articulation of brain areas divided in three subnetworks that extend beyond the classical left-lateralized perisylvian language circuit. Critically, we isolated a subregion of the left angular gyrus showing a significant interaction between gender congruency and gender type. The functional interplay between the angular gyrus and left perisylvian language-specific circuit proves crucial for constructing coherent and meaningful messages. Importantly, using graph theory we show that this complex system is functionally malleable: the role each node plays within the network changes depending on the available linguistic cues.Significance StatementNeural networks can be described as graphs comprising distributed and interconnected nodes. These nodes share functional properties but also differ in terms of functional specialization and the number of interconnections mediating the efficient transfer of information. Previous work has shown functional connectivity differences based on graph-theory properties between typical and atypical samples. However, here we have used concepts from graph theory to characterize connectivity during language processing using task-related fMRI. This approach allowed us to demonstrate how linguistic input drives brain network configuration during language comprehension. This is the first evidence of functional flexibility in language networks: the communicative capacity of each hub changes depending on whether the linguistic input grants access to meaning or is purely formal.

Published online: 11 Feb 2019 Questions under Discussion (QUDs) have been suggested to influence the integration of individual utterances into a discourse-level representation. Previous work has shown that processing ungrammatical ellipses is facilitated when the elided material addresses an implicit QUD raised through a nonactuality implicature (NAIs). It is not clear, however, if QUDs influence discourse coherence during comprehension of fully acceptable discourse. We present two ERP studies examining the effects of QUDs introduced by NAIs using two-sentence discourses. Experiment 1 showed that processing definite NPs with inaccessible antecedents is facilitated when their content is relevant to the QUD. Using acceptable discourses, Experiment 2 showed that definite NPs failing to address a QUD elicit increased processing cost. Overall, our results indicate that QUDs raise the expectation that the following discourse will address them, providing unambiguous evidence that their influence is not limited to the processing of ungrammatical input. This work was supported by the Cluster of Excellence “Multimodal Computing and Interaction” of the German Excellence Initiative and the SFB/CRC 1102 “Information Density and Linguistic Encoding” awarded by the Deutsche Forschungsgemeinschaft (DFG). Further support was provided by the Spanish Ministry of Economy and Competitiveness (MINECO), the Agencia Estatal de Investigacion (AEI), the Fondo Europeo de Desarrollo Regional (FEDER) (grant PSI2015-65694-P, “Severo Ochoa” program SEV-2015-490 for Centers of Excellence in R&D), and the Basque Government (grant PI_2016_1_0014).

Published online: 25 Jul 2019 This work was partially supported by the Ministerio de Economía, Industria y Competitividad, Gobierno de España (MINECO), the Agencia Estatal de Investigación (AEI) and the (Fondo Europeo de Desarrollo Regional FEDER) [grant RTI2018-096311-B-I00, “Severo Ochoa” programme SEV-2015-490 for Centres of Excellence in R&D], and by the Eusko Jaurlaritza Basque government [grant PI_2016_1_0014]. Further support derived from the AThEME project funded by the European Commission 7th Framework Programme, the ERC- 2011-ADG-295362 from the European Research Council.

Published online 7 May 2020 Numbers and letters are culturally created symbols which are learned through repeated training. This experience leads to a functional specialization of the perceptual system of our brain. Recent evidence suggests a neural dissociation between these two symbols. While previous literature has shown that letters elicit a left lateralized neural response, new studies suggest that numbers elicit preferentially a bilateral or right lateralized response. However, the time course of the neural patterns that characterize this dissociation is still underspecified. In the present study, we investigated with magnetoencephalography (MEG) the spatio-temporal dynamics of the neural response generated by numbers, letters and perceptually matched false fonts presented visually. Twenty-five healthy adults were recorded while participants performed a dot detection task. By including two experiments, we were able to study the effects of single characters as well as those of strings of characters. The signal analysis was focused on the event related fields (ERF) of the MEG signal in the sensors and in the source space. The main results of our study showed an early (

Lip-reading is crucial for understanding speech in challenging conditions. But how the brain extracts meaning from--silent--visual speech is still under debate. Lip-reading in silence activates the auditory cortices, but it is not known whether such activation reflects immediate synthesis of the corresponding auditory stimulus or imagery of unrelated sounds.To disentangle these possibilities, we used magnetoencephalography to evaluate how cortical activity in 28 healthy adults humans (17 females) entrained to the auditory speech envelope and lip movements (mouth opening) when listening to a spoken story without visual input (audio-only), and when seeing a silent video of a speaker articulating another story (video-only).In video-only, auditory cortical activity entrained to the absent auditory signal at frequencies below 1 Hz more than to the seen lip movements. This entrainment process was characterized by an auditory-speech-to-brain delay of ∼70 ms in the left hemisphere, compared to ∼20 ms in audio-only Entrainment to mouth opening was found in the right angular gyrus at below 1 Hz, and in early visual cortices at 1-8 Hz.These findings demonstrate that the brain can use a silent lip-read signal to synthesize a coarse-grained auditory speech representation in early auditory cortices. Our data indicate the following underlying oscillatory mechanism: Seeing lip movements first modulates neuronal activity in early visual cortices at frequencies that match articulatory lip movements; the right angular gyrus then extracts slower features of lip movements, mapping them onto the corresponding speech sound features; this information is fed to auditory cortices, most likely facilitating speech parsing.SIGNIFICANCE STATEMENTLip-reading consists in decoding speech based on visual information derived from observation of a speaker's articulatory facial gestures. Lip reading is known to improve auditory speech understanding, especially when speech is degraded. Interestingly, lip-reading in silence still activates the auditory cortices, even when participants do not know what the absent auditory signal should be. However, it was uncertain what such activation reflected. Here, using magnetoencephalographic recordings, we demonstrate it reflects fast synthesis of the auditory stimulus rather than mental imagery of unrelated--speech or non-speech--sounds. Our results also shed light on the oscillatory dynamics underlying lip-reading., info:eu-repo/semantics/published

First published: 24 December 2019 A continuous stream of syllables is segmented into discrete constituents based on the transitional probabilities (TPs) between adjacent syllables by means of statistical learning. However, we still do not know whether people attend to high TPs between frequently co-occurring syllables and cluster them together as parts of the discrete constituents or attend to low TPs aligned with the edges between the constituents and extract them as whole units. Earlier studies on TP-based segmentation also have not distinguished between the segmentation process (how people segment continuous speech) and the learning product (what is learnt by means of statistical learning mechanisms). In the current study, we explored the learning outcome separately from the learning process, focusing on three possible learning products: holistic constituents that are retrieved from memory during the recognition test, clusters of frequently co-occurring syllables, or a set of statistical regularities which can be used to reconstruct legitimate candidates for discrete constituents during the recognition test. Our data suggest that people employ boundary-finding mechanisms during online segmentation by attending to low inter-syllabic TPs during familiarization and also identify potential candidates for discrete constituents based on their statistical congruency with rules extracted during the learning process. Memory representations of recurrent constituents embedded in the continuous speech stream during familiarization facilitate subsequent recognition of these discrete constituents. Secretaría de Estado de Investigación, Desarrollo e Innovación, Grant/Award Number: RTI2018-098317-B-I00 ; H2020 Marie Skłodowska-Curie Actions, Grant/Award Number: DLV-792331; Ekonomiaren Garapen eta Lehiakortasun Saila, Eusko Jaurlaritza, Grant/Award Number: PI-2017-25; Spanish Ministry of Economy and Competitiveness (MINECO) through the “Severo Ochoa” Programme for Centres/Units of Excellence in R&D, Grant/Award Number: SEV-2015-490; Basque Government, Grant/Award Number: PI-2017-25; European Commission through the Marie Skłodowska-Curie Research Fellowship

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.

To gain novel insights into how the human brain processes self-produced auditory information during reading aloud, we investigated the coupling between neuromagnetic activity and the temporal envelope of the heard speech sounds (i.e., speech brain tracking) in a group of adults who 1) read a text aloud, 2) listened to a recording of their own speech (i.e., playback), and 3) listened to another speech recording. Coherence analyses revealed that, during reading aloud, the reader’s brain tracked the slow temporal fluctuations of the speech output. Specifically, auditory cortices tracked phrasal structure (HighlightsThe brain tracks phrasal and syllabic rhythmicity of self-produced (read) speech.Tracking of phrasal structures is attenuated during reading compared with listening.Speech rhythmicity mainly drives brain activity during reading and listening.Brain activity drives syllabic rhythmicity more during reading than listening.

Low‐ and high‐frequency cortical oscillations play an important role in speech processing. Low‐frequency neural oscillations in the delta (, Here, we found that the phase of theta band oscillations in left and right auditory regions adjusts to speech rate variations. Importantly, we showed that the peak of the gamma response—coupled to the phase of theta—follows the speech rate. This indicates that gamma activity in auditory regions synchronizes with the fine‐grain properties of speech, possibly reflecting detailed acoustic analysis of the input.

Available online 17 September 2019. This longitudinal study was aimed at testing the relation between rhythm sensitivity and behavioural and neural orthographic sensitivity in pre-reading stages. Basque-speaking children performed several behavioural and EEG tasks at two time points prior to formal reading acquisition (T1: 4 years old; T2: 5 years old). Neural sensitivity to print was measured via a novel child friendly N170-elicitation paradigm. Our results highlight a transversal and longitudinal relation between rhythm sensitivity and letter name knowledge in pre-reading children. Moreover, they show that children’s rhythm sensitivity predicts a significant part of the variance of their N170 response one year later, highlighting the potential of rhythm tasks to predict future orthographic sensitivity in pre-reading stages. Interestingly, the relation between rhythmic skills and print sensitivity was not mediated by the children’s phonological short-term memory. Our results provide novel evidence on the importance of rhythm sensitivity for the development of early orthographic sensitivity. This work was supported by the Severo Ochoa Program grant [SEV-2015-049]; ML 16 was supported by the Spanish Ministry of Economy and Competitiveness [RTI2018-17 096242-B-I00, Ramón y Cajal Fellowship]; NL was supported by the Spanish Ministry 18 of Economy and Competitiveness [PSI2015-65694-P], the Basque Government 19 [PI_2016_1_0014], the European Commission 7th Framework Programme (AThEME 20 project) and the European Research Council (ERC-2011-ADG-295362).

Developmental dyslexia is a reading disorder often characterized by reduced awareness of speech units. Whether the neural source of this phonological disorder in dyslexic readers results from the malfunctioning of the primary auditory system or damaged feedback communication between higher-order phonological regions (i.e., left inferior frontal regions) and the auditory cortex is still under dispute. Here we recorded magnetoencephalographic (MEG) signals from 20 dyslexic readers and 20 age-matched controls while they were listening to ∼10-s-long spoken sentences. Compared to controls, dyslexic readers had (1) an impaired neural entrainment to speech in the delta band (0.5-1 Hz); (2) a reduced delta synchronization in both the right auditory cortex and the left inferior frontal gyrus; and (3) an impaired feedforward functional coupling between neural oscillations in the right auditory cortex and the left inferior frontal regions. This shows that during speech listening, individuals with developmental dyslexia present reduced neural synchrony to low-frequency speech oscillations in primary auditory regions that hinders higher-order speech processing steps. The present findings, thus, strengthen proposals assuming that improper low-frequency acoustic entrainment affects speech sampling. This low speech-brain synchronization has the strong potential to cause severe consequences for both phonological and reading skills. Interestingly, the reduced speech-brain synchronization in dyslexic readers compared to normal readers (and its higher-order consequences across the speech processing network) appears preserved through the development from childhood to adulthood. Thus, the evaluation of speech-brain synchronization could possibly serve as a diagnostic tool for early detection of children at risk of dyslexia. Hum Brain Mapp 37:2767-2783, 2016. © 2016 Wiley Periodicals, Inc.