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BACKGROUND Rasmussen encephalitis is a rare chronic neurological pathology frequently treated with functional hemispherectomy (or hemispherotomy). This surgical procedure frees patients of their severe epilepsy associated with the disease but may induce cognitive disorders and notably language alterations after disconnection of the left hemisphere. OBSERVATIONS The authors describe longitudinally 3 cases of female patients with Rasmussen encephalitis who underwent left hemispherotomy in childhood and benefited from a favorable cognitive outcome. In the first patient, the hemispherotomy occurred at a young age, and the recovery of language and cognitive abilities was rapid and efficient. The second patient benefited from the surgery later in childhood. In addition, she presented a reorganization of language and memory functions that seem to have been at the expense of nonverbal ones. The third patient was a teenager during surgery. She benefited from a more partial cognitive recovery with persistent disorders several years after the surgery. LESSONS Recovery of cognitive functions, including language, occurs after left hemispherotomy, even when performed late in childhood. Therefore, the surgery should be considered as early as possible to promote intercognitive reorganization.

There is no consensus regarding clear-cut brain functional dissociations of semantic and syntactic information processing networks. Recent studies proposed a functional dissociation at the spectral level in which semantic and syntactic processes were associated with neural network activity at different frequency intervals. This study aimed at investigating this functional dissociation for semantic and syntactic information during auditory language comprehension. For this purpose, we collaborated with 11 drug-resistant epilepsy patients undergoing deep electrode implantation brain recordings. Patients were instructed to listen to four different types of auditory stimuli (in which semantic and syntactic information were manipulated): sentences, jabberwockys, word lists, and pseudoword lists. Results showed no clear dissociation between semantic and syntactic processing in the left language canonical network. In the temporo-parietal regions two distinct subnetworks, each with its own spectral signature, were observed. Semantic information processing appeared to elicit stronger high frequency activity in the temporal pole, while syntactic information processing elicited low frequency activity increases in the middle temporal as well as the supramarginal gyri. Interestingly, a specific spectral functional dissociation in the pars triangularis was observed suggesting that a single region could support both functional processes within distinct neural frequency intervals.

Purpose: Canonical sentence structures are the most frequently used in a given language. Less frequent or non-canonical sentences tend to be more challenging to process and to induce a higher cognitive load. To deal with this complexity several authors suggest that not only linguistic but also non-linguistic (domain-general) mechanisms are involved. In this study, we were interested in evaluating the relationship between non-canonical oral sentence comprehension and individual cognitive control abilities.Method: Participants were instructed to perform a sentence-picture verification task with canonical and non-canonical sentences. Sentence structures (i.e., active or passive) and sentence types (i.e., affirmative or negative) were manipulated. Furthermore, each participant performed four cognitive control tasks measuring inhibitory processes, updating in working memory, flexibility and sustained attention. We hypothesized that more complex sentence structures would induce a cognitive cost reflecting involvement of additional processes, and also that this additional cost should be related with cognitive control performances.Results: Results showed better performances for canonical sentences compared to non-canonical ones supporting previous work on passive and negative sentence processing. Correlation results suggest a close relationship between cognitive control mechanisms and non-canonical sentence processing.Conclusion: This study adds evidence for the hypothesis of a domain-general mechanism implication during oral language comprehension and highlights the importance of taking task demands into consideration when exploring language comprehension mechanisms.

Lexical ambiguity is ubiquitous in oral language and sometimes induces comprehension difficulties. Moreover, in ecological situations language is rarely processed without any surrounding noise and one of the more frequent situations of language comprehension is speech-in-speech situations. In the present study we evaluated the cognitive process at work during online sentences comprehension in which comprehension difficulties were manipulated by linguistic ambiguity (using French homophones) and the presence or absence of babble noise (multi-talker situations). Eye movements on a visual scene including four different images (correct target, an incorrect target, a semantic distractor and a phonological distractor) were measured to assess online effects of lexical ambiguity and noise processing during language comprehension. We hypothesized that looks to the incorrect target would increase with ambiguity and that this increase would be amplified with babble noise. Also, looks to the phonological and semantic distractors should be higher in the speech-in-speech situation than in silence. Furthermore, we hypothesize that in more difficult linguistic situations comprehension will be related with the better cognitive control of participants. Consequently, we also evaluated cognitive control performances during three cognitive control tasks (evaluating: attentional control, inhibitory control and updating in working memory abilities). Results showed significant effects of lexical ambiguity and multi-talker situations on behavioral performances and eye movement measures, suggesting that additional difficulty in language comprehension increased cognitive effort and processing. Combination of both difficult conditions induced the lowest performances but the interaction effect suggests a smaller impact of ambiguity in a speech-in-speech situation than in silence. Results also showed that the bigger the interference or difficulty cost in cognitive control tasks the bigger the ambiguity effect in the language comprehension task. Results are discussed in light of the literature linking cognitive control and language processing.

A fundamental question is whether language comprehension involves specific cognitive mechanisms to decode linguistic information, or whether language comprehension occurs through the interaction with other specialized cognitive systems. Accumulated behavioral and neuroimaging evidence suggests that, in several situations, the language system interacts with the executive control system. In the same time as brain maturation and learning, language comprehension and cognitive control abilities are changing through the different periods of life. In this article, we review behavioral, neuroimaging and neuropsychological evidences of a close relationship between language comprehension and cognitive control with a lifespan approach. Most evidence proposed in this article are in monolingual populations but a consideration of the specific case of bilingualism is made. We propose that a better specification and comprehension of the interaction between language and cognitive control abilities could improve understanding of language mechanisms and its deficits and also open new avenues to develop better rehabilitation programs.

We present a computerize battery constructed to evaluate behavioral performances for language, declarative memory, executive functions and social cognition abilities. This battery was created to evaluate cognitive outcomes in adults who underwent hemispherotomy as a clinical treatment of Rasmussen Encephalitis (RE) in their childhood and have been tested in a group of healthy participants (n= 88). LEXTOMM battery can be used for cognitive assessment of any type of population and allow the collection of behavioral performances in terms of accuracy and reaction times. LEXTOMM battery is composed of six language tasks allowing to assess six different linguistic abilities such as lexical storage, semantics, phonology, syntax, prosody perception and production. Different input modalities are proposed for these tasks (picture, written and auditory modality). A specific task allowing the assessment of the language generation and declarative memory interaction is also proposed. The battery also included a visual control categorization task is proposed in order to assess decision-making baseline. Moreover, LEXTOMM also includes four tasks allowing the assessment of the executive functions. More specifically we included tasks allowing the evaluation of four executive processes: updating in working memory, switching/flexibility, sustained attention and inhibition. Finally, the battery includes a theory of mind abilities task. All tasks were developed using the E-Prime 3.0 software (E-Prime Psychology Software Tools Inc., Pittsburgh, USA), running on a PC. Before each task, a training session is included, with several stimuli that differ from those presented during the experiment. This training allows participants to understand the instructions and get familiarized with each task. Hereafter, we describe the procedures and tasks included in LEXTOMM, in the following order: low-level visual categorization, language, language in interaction with declarative memory, executive functions and social cognition/theory of mind.

In the absence of any neuropsychiatric condition, older adults may show declining performance in several cognitive processes and among them, in retrieving and producing words, reflected in slower responses and even reduced accuracy compared to younger adults. To overcome this difficulty, healthy older adults implement compensatory strategies, which are the focus of this paper. We provide a review of mainstream findings on deficient mechanisms and possible neurocognitive strategies used by older adults to overcome the deleterious effects of age on lexical production. Moreover, we present findings on genetic and lifestyle factors that might either be protective or risk factors of cognitive impairment in advanced age. We propose that “aging-modulating factors” (AMF) can be modified, offering prevention opportunities against aging effects. Based on our review and this proposition, we introduce an integrative neurocognitive model of mechanisms and compensatory strategies for lexical production in older adults (entitled Lexical Access and Retrieval in Aging, LARA). The main hypothesis defended in LARA is that cognitive aging evolves heterogeneously and involves complementary domain-general and domain-specific mechanisms, with substantial inter-individual variability, reflected at behavioral, cognitive, and brain levels. Furthermore, we argue that the ability to compensate for the effect of cognitive aging depends on the amount of reserve specific to each individual which is, in turn, modulated by the AMF. Our conclusion is that a variety of mechanisms and compensatory strategies coexist in the same individual to oppose the effect of age. The role of reserve is pivotal for a successful coping with age-related changes and future research should continue to explore the modulating role of AMF. Supplementary Information The online version contains supplementary material available at 10.1007/s11357-021-00367-5.

In the present preregistered study, we evaluated the possibility of a shared cognitive mechanism during verbal and non-verbal tasks and therefore the implication of domain-general cognitive control during language comprehension. We hypothesized that a behavioral cost will be observed during a dual-task including both verbal and non-verbal difficult processing. Specifically, to test this claim, we designed a dual-task paradigm involving: an auditory language comprehension task (sentence comprehension) and a non-verbal Flanker task (including congruent and incongruent trials). We manipulated sentence ambiguity and evaluated if the ambiguity effect modified behavioral performances in the non-verbal Flanker task. Under the assumption that ambiguous sentences induce a more difficult process than unambiguous sentences, we expected non-verbal flanker task performances to be impaired only when a simultaneous difficult language processing is performed. This would be specifically reflected by a performance cost during incongruent Flanker items only during ambiguous sentence presentation. Conversely, we observed a facilitatory effect for the incongruent Flanker items during ambiguous sentence suggesting better non-verbal inhibitory performances when an ambiguous sentence was simultaneously processed. Exploratory data analysis suggests that this effect is not only related to a more difficult language processing but also to the previous (n-1) Flanker item. Indeed, results showed that incongruent n-1 Flanker items led to a facilitation of the incongruent synchronized Flanker items only when ambiguous sentences were conjointly presented. This result, even if it needs to be corroborated in future studies, suggests that the recruitment of executive control mechanisms facilitates subsequent executive control implication during difficult language processing. The present study suggests a common executive control mechanism during difficult verbal and non-verbal tasks.

In the present preregistered study, we evaluated the impact of linguistic ambiguity processing on non-verbal inhibitory processing in a dual-task paradigm. We assessed whether a shared mechanism is involved during verbal and non-verbal conflict resolution. To do so, we constructed a dual-task paradigm including an auditory language comprehension and a non-verbal Flanker task. The language comprehension stimuli included sentences with French homophones presenting a temporary ambiguity (ambiguous sentences) or not (control sentences). The Flanker task included congruent (low executive control load) and incongruent (high executive control load) trials that were synchronized or not with the homophone in the sentence. We hypothesized that if the homophone meaning selection requires executive control this would interfere with executive control performance of the concomitant Flanker trials. This would be reflected by a performance cost during incongruent Flanker trials for the ambiguous sentences only. Surprisingly, we observed a facilitatory effect during ambiguous sentences on incongruent Flanker trials suggesting better non-verbal inhibitory performances when homophone conflict resolution was simultaneously performed. Exploratory data analysis suggests that this effect is not only related to ambiguity resolution processing but also to the previous (n-1) Flanker trial. Indeed, results showed that incongruent n-1 Flanker trials led to a facilitation of the incongruent target Flanker trials only when ambiguous sentences were conjointly presented. This result, even if it remains to be corroborated in future studies, suggests that the recruitment of executive control mechanisms facilitates subsequent executive control implication during difficult language processing. The present study supports the view of a common executive control mechanism during conflict resolution in verbal and non-verbal tasks.

Human brain has developed mechanisms to efficiently decode sensory information according to perceptual categories of high prevalence in the environment, such as faces, symbols, objects. Neural activity produced within localized brain networks has been associated with the process that integrates both sensory bottom-up and cognitive top-down information processing. Yet, how specifically the different types and components of neural responses reflect the local networks' selectivity for categorical information processing is still unknown. By mimicking the decoding of the sensory information with machine learning we can obtain accurate artificial decoding models. Having the artificial system functionally on par with the biological one we can analyze the mechanics of the artificial system to gain insights into the inner workings of its biological counterpart. In this work we train a Random Forest classification model to decode eight perceptual categories from visual stimuli given a broad spectrum of human intracranial signals 4-150 Hz obtained during a visual perception task, and analyze which of the spectral features the algorithm deemed relevant to the perceptual decoding. We show that network selectivity for a single or multiple categories in sensory and non-sensory cortices is related to specific patterns of power increases and decreases in both low 4-50 Hz and high 50-150 Hz frequency bands. We demonstrate that the locations and patterns of activity that are identified by the algorithm not only coincide with the known spectro-spatial signatures, but extend our knowledge by uncovering additional spectral signatures describing neural mechanisms of visual category perception in human brain.

Direct electrical stimulation (DES) at 50 Hz is used as a gold standard to map cognitive functions but little is known about its ability to map large‐scale networks and specific subnetwork. In the present study, we aim to propose a new methodological approach to evaluate the specific hypothesis suggesting that language errors/dysfunction induced by DES are the result of large‐scale network modification rather than of a single cortical region, which explains that similar language symptoms may be observed after stimulation of different cortical regions belonging to this network. We retrospectively examined 29 patients suffering from focal drug‐resistant epilepsy who benefitted from stereo‐electroencephalographic (SEEG) exploration and exhibited language symptoms during a naming task following 50 Hz DES. We assessed the large‐scale language network correlated with behavioral DES‐induced responses (naming errors) by quantifying DES‐induced changes in high frequency activity (HFA, 70–150 Hz) outside the stimulated cortical region. We developed a probabilistic approach to report the spatial pattern of HFA modulations during DES‐induced language errors. Similarly, we mapped the pattern of after‐discharges (3–35 Hz) occurring after DES. HFA modulations concurrent to language symptoms revealed a brain network similar to our current knowledge of language gathered from standard brain mapping. In addition, specific subnetworks could be identified within the global language network, related to different language processes, generally described in relation to the classical language regions. Spatial patterns of after‐discharges were similar to HFA induced during DES. Our results suggest that this new methodological DES‐HFA mapping is a relevant approach to map functional networks during SEEG explorations, which would allow to shift from “local” to “network” perspectives., We adopted a new probabilistic brain mapping approach based on direct cortical stimulation and high frequency activity measures during naming task. Our results suggest that this new methodological direct electrical stimulation‐high frequency activity mapping is a relevant approach to map functional networks during stereo‐electroencephalographic explorations, which would allow to shift from “local” to “network” perspectives.

Previous studies have highlighted the importance of considering cognitive functions from a dynamic and interactive perspective and multiple evidence was brought for a language and memory interaction. In this study performed with healthy participants, we present a new protocol entitled GE2REC that interactively accesses the neural representation of language-and-memory network. This protocol consists of three runs related to each other, providing a link between tasks, in order to assure an interactive measure of linguistic and episodic memory processes. GE2REC consists of a sentence generation (GE) in the auditory modality and two recollecting (2REC) memory tasks, one recognition performed in the visual modality, and another one recall performed in the auditory modality. Its efficiency was evaluated in 20 healthy volunteers using a 3T MR imager. Our results corroborate the ability of GE2REC to robustly activate fronto-temporo-parietal language network as well as temporal mesial, prefrontal and parietal cortices in encoding during sentence generation and recognition. GE2REC is useful because it: (a) requires simultaneous and interactive language-and-memory processes and jointly maps their neural basis; (b) explores encoding and retrieval, managing to elicit activation of mesial temporal structures; (c) is easy to perform, hence being suitable for more restrictive settings, and (d) has an ecological dimension of tasks and stimuli. GE2REC may be useful for studying neuroplasticity of cognitive functions, especially in patients with temporal lobe epilepsy who show reorganization of both language and memory networks. Overall, GE2REC can provide valuable information in terms of the practical foundation of exploration language and memory interconnection. Electronic supplementary material The online version of this article (10.1007/s11682-020-00355-x) contains supplementary material, which is available to authorized users.

International audience; Both syntax and Executive Functions (EF) are involved in Theory-of-Mind (ToM) but their contributory roles have mainly been studied separately. Moreover, researchers have mostly administered False Belief (FB) tasks while they may not be representative of all ToM abilities. Studies of adults give valuable information regarding whether syntax and EF are useful for ToM reasoning (i.e., Reasoning account), however, only the study of children brings direct evidence in favor of ToM emergence (i.e., Emergence account). Also, because the ToM tasks used often entail verbal and executive demands, the links observed could mostly result from such confounds (i.e., Expression account). We evaluated ToM, syntactic and EF abilities in 126 children (3-11 y.o.) using a set of ToM tasks with minimal verbal and executive demands. Our goals were to assess (1) the hierarchical contribution of syntax and EF to ToM, (2) whether results previously obtained for FB tasks are representative of ToM in general, (3) whether the ToM-syntax and ToM-EF links are constant (i.e., Reasoning account) or decrease during development (i.e., Emergence accounts). Results of stepwise regression analyses showed a predominant role of syntax over EF to predict ToM abilities. The comparison of results for ToM and FB tasks showed that FB is not always representativeof ToM. Finally, there was no moderating effect of age on the syntax-ToM or EF-ToM relations, thus suggestive of the Reasoning account rather than the Emergence account.

Adaptive behavior requires the comparison of outcome predictions with actual outcomes (e.g., performance feedback). This process of performance monitoring is computed by a distributed brain network comprising the medial prefrontal cortex (mPFC) and the anterior insular cortex (AIC). Despite being consistently co-activated during different tasks, the precise neuronal computations of each region and their interactions remain elusive. In order to assess the neural mechanism by which the AIC processes performance feedback, we recorded AIC electrophysiological activity in humans. We found that the AIC beta oscillations amplitude is modulated by the probability of performance feedback valence (positive or negative) given the context (task and condition difficulty). Furthermore, the valence of feedback was encoded by delta waves phase-modulating the power of beta oscillations. Finally, connectivity and causal analysis showed that beta oscillations relay feedback information signals to the mPFC. These results reveal that structured oscillatory activity in the anterior insula encodes performance feedback information, thus coordinating brain circuits related to reward-based learning.

OBJECTIVE The authors assessed the clinical relevance of preoperative task-induced high-frequency activity (HFA) for language mapping in patients with refractory epilepsy during stereoelectroencephalography recording. Although HFA evaluation was described as a putative biomarker of cognition, its clinical relevance for mapping language networks was assessed predominantly by studies using electrocorticography (ECOG). METHODS Forty-two patients with epilepsy who underwent intracranial electrode implantation during both task-induced HFA and direct cortical stimulation (DCS) language mapping were evaluated. The spatial and functional relevance of each method in terms of specificity and sensitivity were evaluated. RESULTS The results showed that the two methods were able to map classic language regions, and a large and bilateral language network was obtained with induced HFA. At a regional level, differences were observed between methods for parietal and temporal lobes: HFA recruited a larger number of cortical parietal sites, while DCS involved more cortical temporal sites. Importantly, the results showed that HFA predicts language interference induced by DCS with high specificity (92.4%; negative predictive value 95.9%) and very low sensitivity (8.9%; positive predictive value 4.8%). CONCLUSIONS DCS language mapping appears to be more appropriate for an extensive temporal mapping than induced HFA mapping. Furthermore, induced HFA should be used as a complement to DCS to preselect the number of stimulated sites during DCS, by omitting those reported as HFA−. This may be a considerable advantage because it allows a reduction in the duration of the stimulation procedure. Several parameters to be used for each method are discussed and the results are interpreted in relation to previous results reported in ECOG studies.

Previous research showed that mental rumination, considered as a form of repetitive and negative inner speech, is associated with increased facial muscular activity. However, the relation between these muscular activations and the underlying mental processes is still unclear. In this study, we tried to separate the facial electromyographic correlates of induced rumination related to either i) mechanisms of (inner) speech production or ii) rumination as a state of pondering on negative affects. To this end, we compared two groups of participants submitted to two types of rumination induction (for a total of 85 female undergraduate students without excessive depressive symptoms). The first type of induction was designed to specifically induce rumination in a verbal modality whereas the second one was designed to induce rumination in a visual modality. Following the *motor simulation view* of inner speech production, we hypothesised that the verbal rumination induction should result in a higher increase of activity in the speech-related muscles as compared to the non-verbal rumination induction. We also hypothesised that relaxation focused on the orofacial area should be more efficient in reducing rumination (when experienced in a verbal modality) than a relaxation focused on a non-orofacial area. Our results do not corroborate these hypotheses, as both rumination inductions resulted in a similar increase of peripheral muscular activity in comparison to baseline levels. Moreover, the two relaxation types were similarly efficient in reducing rumination, whatever the rumination induction. We discuss these results in relation to the inner speech literature and suggest that because rumination is a habitual and automatic form of emotion regulation, it might be a particularly (strongly) internalised and condensed form of inner speech. Pre-registered protocol, preprint, data, as well as reproducible code and figures are available at: https://osf.io/c9pag/.

Although having a long history of scrutiny in experimental psychology, it is still controversial whether inner speech (covert speech) production is accompanied by specific activity in speech muscles. We address this question by briefly reviewing previous findings related to inner speech and to the broader phenomenon of motor imagery. We then present the results of a preregistered experiment looking at the electromyographic correlates of both overt speech and inner speech production of two phonetic classes of nonwords. An automatic classification approach was undertaken to discriminate between two articulatory features contained in nonwords uttered in both overt and covert speech. Although this approach led to reasonable accuracy rates during overt speech production, it failed to discriminate inner speech phonetic content based on surface electromyography signals alone. However, exploratory analyses conducted at the individual level revealed that it seemed possible to distinguish between rounded and spread nonwords covertly produced, in two participants. We discuss these results in relation to the existing literature and suggest alternative ways to test the engagement of the speech motor system during inner speech production. Pre-registered protocol, preprint, data, as well as reproducible code and figures are available at: https://osf.io/czer4/.

The decision to process an incoming stimulus attentively - and to trigger a follow-up cascade of high-level processes - is strategic for the human brain as it becomes transiently unavailable to subsequent stimulus processing. In this study, we set to identify brain networks that carry out such evaluations. We therefore assessed the time-course of neural responses with intracerebral EEG in human patients during an attentional reading task, contrasting to-be-attended vs. to-be-ignored items. We measured High-Frequency Activity [50–150 ​Hz] as a proxy of population-level spiking activity and we identified a crucial component of a Gate-Keeping Mechanism bilateral in the mid-Ventro-Lateral Prefrontal Cortex (VLPFC), at the interplay of the Ventral and Dorsal Attention Networks, that selectively reacts before domain specialized cortical regions that engage in full stimulus analysis according to task demands.

We report two patients suffering from drug-resistant temporal lobe epilepsy to show how their neuroplasticity can be apprehended using a multimodal, integrative and clinically relevant approach. This is a proof of concept based on using multimodal data including: (1) white matter structural connectivity (DTI) of the main tracts involved in language and memory; (2) neurophysiological biomarkers (fMRI-BOLD signal and LI lateralization indices); and (3) cognitive scores as measured during the neuropsychological assessment. We characterized tri-modal data for each patient using a descriptive integrative approach, in terms of reorganization and by comparing with a group of healthy participants. This proof of concept suggests that the inclusion of multimodal data in clinical studies is currently a major challenge. Since the various datasets obtained from MRI neuroimaging and cognitive scores are probably interrelated, it is important to go beyond the mono-modal approach and move towards greater integration of several multimodal data. Multimodal integration of anatomical, functional, and cognitive data facilitates the identification of comprehensive neurocognitive patterns in epileptic patients, thus enabling clinicians to differentiate between reorganization profiles and help to predict post-surgical outcomes for curative neurosurgery.

Background Pure attentional deficits are still underdiagnosed in children with epilepsy. While attention-deficit hyperactivity disorder (ADHD) is historically the most studied cause of attentional disorders, an important number of children with epilepsy and attentional complaints do not fully meet the DSM-V (Diagnostic and Statistical Manual of Mental Disorders - Fifth Edition) criteria for ADHD and may be excluded from specific care. Clinical tools currently available are insufficient to detect more subtle but clinically relevant attentional fluctuations. Objective/methods The recently developed Bron–Lyon Attention Stability Test (BLAST) was used to evaluate brief attentional fluctuations with a high temporal precision. Drawing on two new attentional indices, we evaluated spontaneous fluctuations of response accuracy and timing, underlying attentional stability. The main objective was to assess attentional stability in children with i) epilepsy with comorbid ADHD, ii) epilepsy without comorbid ADHD, iii) ADHD not medicated and without epilepsy, and iv) normal development. Further objectives were to assess the main determinants of attentional stability in those groups, including the effect of factors related to the epileptic condition. Results In 122 children with epilepsy (67 with comorbid ADHD), 52 children with ADHD, and 53 healthy controls, we demonstrated lower attentional stability in both the groups with epilepsy and ADHD compared with healthy children. In children with epilepsy, BLAST scores were negatively associated with earlier seizure onset and AED (antiepileptic drug) polytherapy, while the seizure frequency, epilepsy duration, or type did not influence BLAST scores. Conclusions This study demonstrates that attentional stability is impaired in children with epilepsy and/or ADHD. Bron–Lyon Attention Stability Test seems to be a sensitive test to detect attentional stability deficit in children with epilepsy and with attentional complaints who did not meet all criteria of ADHD. We propose that BLAST could be a useful clinical neuropsychological tool to assess attentional disorders in children.

Inner speech has been shown to vary in form along several dimensions. Along condensation, condensed inner speech forms have been described, that are supposed to be deprived of acoustic, phonological and even syntactic qualities. Expanded forms, on the other extreme, display articulatory and auditory properties. Along dialogality, inner speech can be monologal, when we engage in internal soliloquy, or dialogal, when we recall past conversations or imagine future dialogs involving our own voice as well as that of others addressing us. Along intentionality, it can be intentional (when we deliberately rehearse material in short-term memory) or it can arise unintentionally (during mind wandering). We introduce the ConDialInt model, a neurocognitive predictive control model of inner speech that accounts for its varieties along these three dimensions. ConDialInt spells out the condensation dimension by including inhibitory control at the conceptualization, formulation or articulatory planning stage. It accounts for dialogality, by assuming internal model adaptations and by speculating on neural processes underlying perspective switching. It explains the differences between intentional and spontaneous varieties in terms of monitoring. We present an fMRI study in which we probed varieties of inner speech along dialogality and intentionality, to examine the validity of the neuroanatomical correlates posited in ConDialInt. Condensation was also informally tackled. Our data support the hypothesis that expanded inner speech recruits speech production processes down to articulatory planning, resulting in a predicted signal, the inner voice, with auditory qualities. Along dialogality, covertly using an avatar’s voice resulted in the activation of right hemisphere homologs of the regions involved in internal own-voice soliloquy and in reduced cerebellar activation, consistent with internal model adaptation. Switching from first-person to third-person perspective resulted in activations in precuneus and parietal lobules. Along intentionality, compared with intentional inner speech, mind wandering with inner speech episodes was associated with greater bilateral inferior frontal activation and decreased activation in left temporal regions. This is consistent with the reported subjective evanescence and presumably reflects condensation processes. Our results provide neuroanatomical evidence compatible with predictive control and in favor of the assumptions made in the ConDialInt model.

Neural correlates of cognitive planning are not understood well at present. Behavioral paradigms targeting this function are a current challenge in cognitive neuroscience. We recorded EEG activity while subjects were performing a novel behavioral paradigm that evaluates cognitive planning function. Participants showed longer reaction times and decreased accuracy during the planning condition compared to the control condition, suggesting that the planning condition is more time consuming, therefore reflecting higher cognitive demand. Moreover, cognitive planning induced a frontal midline theta (FMθ) frequency band originating in prefrontal cortex (PFC) as shown in previous cognitive control studies. When subjects began planning, there was a progressive and sustained increase in FMθ starting after 500 milliseconds (ms) of planning. Hence, we characterized for first time, both spatial and temporal FMθ dynamics of cognitive planning as a marker of cognitive control function.

International audience; This article provides an exhaustive description of a new short computerized test to assess on a second-to-second basis the ability of individuals to « stay on task », that is, to apply selectively and repeatedly task-relevant cognitive processes. The task (Bron/Lyon Attention Stability Test, or BLAST) lasts around 1 min, and measures repeatedly the time to find a target letter in a two-by-two letter array, with an update of all letters every new trial across thirty trials. Several innovative psychometric measures of attention stability are proposed based on the instantaneous fluctuations of reaction times throughout the task, and normative data stratified over a wide range of age are provided by a large (>6000) dataset of participants aged 8 to 70. We also detail the large-scale brain dynamics supporting the task from an in-depth study of 32 participants with direct electrophysiological cortical recordings (intracranial EEG) to prove that BLAST involves critically large-scale executive attention networks, with a marked activation of the dorsal attention network and a deactivation of the default-mode network. Accordingly, we show that BLAST performance correlates with scores established by ADHD-questionnaires.

The article Interactive mapping of language and memory with the GE2REC protocol, written by Sonja Banjac, Elise Roger, Emilie Cousin, Marcela Perrone-Bertolotti, Celise Haldin, Cedric Pichat, Laurent Lamalle, Lorella Minotti, Philippe Kahane, and Monica Baciu was originally published electronically on the publisher’s internet portal on August 06, 2020 without open access.

The nature of inner language has long been under the scrutiny of humanities, through the practice of introspection. The use of experimental methods in cognitive neurosciences provides complementary insights. This chapter focuses on wilful expanded inner language, bearing in mind that other forms coexist. It first considers the abstract vs. concrete (or embodied) dimensions of inner language. In a second section, it argues that inner language should be considered as an action-perception phenomenon. In a third section, it proposes a revision of the “predictive control” account, fitting with our sensory-motor view. Inner language is considered as deriving from multisensory goals, generating multimodal acts (inner phonation, articulation, sign) with multisensory percepts (in the mind’s ear, tact, and eye). In the final section, it presents a landscape of the cerebral substrates of wilful inner verbalization, including multisensory and motor cortices as well as cognitive control networks.

International audience; The nature of inner language has long been under the scrutiny of humanities, through the practice of introspection. The use of experimental methods in cognitive neurosciences provides complementary insights. This chapter focuses on wilful expanded inner language, bearing in mind that other forms coexist. It first considers the abstract vs. concrete (or embodied) dimensions of inner language. In a second section, it argues that inner language should be considered as an action-perception phenomenon. In a third section, it proposes a revision of the « predictive control » account, fitting with our sensory-motor view. Inner language is considered as deriving from multisensory goals, generating multimodal acts (inner phonation, articulation, sign) with multisensory percepts (in the mind's ear, tact and eye). In the final section, it presents a landscape of the cerebral substrates of wilful inner verbalization, including multisensory and motor cortices as well as cognitive control networks.

International audience; – Increasing attention is being paid to the assessment of white matter properties and its structural connectivity, both in healthy subjects and patients with cerebral lesions. Within this framework, new neurocogni-tive models based on hodological properties have been developed under a connectomic perspective in order to explain substrates and cognitive mechanisms related to cerebral functions such as language and memory. With regards to focal and drug-resistant epilepsy conceived as a network disorder , new insights in terms of structural connectivity have led to significant advances in epilepsy research, concerning fundamental research (neu-rocognitive mechanisms of plasticity) and clinical application (optimization of decision making for curative surgery). We believe that such findings in the literature, focused on the role of white matter in cerebral functioning in relation to neurocognition, may be helpful for both researchers and clinicians working in the field of epilepsy. Structural connectivity and neurocognition: general information Structural connectivity refers to the study of the anatomical features of brain networks in terms of subcorti-cal white matter (WM) that underlies interconnections between different cortical regions. Within the current context of growing interest with a connectomic perspective, many MRI methods and parameters are now available to assess WM anatomical properties including architecture, spatial trajectory, density or integrity (Sporns, 2013). These structural properties, investigated in relation to cognitive functions and behavioral performance, allows the development of more

The goal of the current study was to statistically evaluate the reliable scalability of a set of tasks designed to assess Theory of Mind (ToM) without language as a confounding variable. This tool might be useful to study ToM in populations where language is impaired or to study links between language and ToM. Low verbal versions of the ToM tasks proposed by Wellman and Liu (2004) for their scale were tested in 234 children (2.5 years to 11.9 years). Results showed that 5 of the tasks formed a scale according to both Guttman and Rasch models whereas all 6 tasks could form a scale according to the Rasch model only. The main difference from the original scale was that the Explicit False Belief task could be included whereas the Knowledge Access (KA) task could not. The authors argue that the more verbal version of the KA task administered in previous studies could have measured language understanding rather than ToM. (PsycINFO Database Record

International audience; Ripples are high-frequency bouts of coordinated hippocampal activity believed to be crucial for information transfer and memory formation. We used intracortical macroelectrodes to record neural activity in the human hippocampus of awake subjects undergoing surgical treatment for refractory epilepsy and distinguished two populations of ripple episodes based on their frequency spectrum. The phase-coupling of one population, slow ripples (90e110 Hz), to cortical delta oscillations was differentially modulated by cognitive task; whereas the second population, fast ripples (130e170 Hz), was not seemingly correlated to local neural activity. Furthermore, as cognitive tasks changed, the ongoing coordination of neural activity associated to slow ripples progressively augmented along the parahippocampal axis. Thus, during resting states, slow ripples were coordinated in restricted hippocampal territories; whereas during active states, such as attentionallydemanding tasks, high frequency activity emerged across the hippocampus and parahippocampal cortex, that was synchronized with slow ripples, consistent with ripples supporting information transfer and coupling anatomically distant regions. Hence, our results provide further evidence of neural diversity in hippocampal high-frequency oscillations and their association to cognitive processing in humans.

International audience; It has been suggested that dorsal and ventral pathways support distinct aspects of language processing. Yet, the full extent of their involvement and their inter-regional connectivity in visual word recognition is still unknown. Studies suggest that they might reflect the dual-route model of reading, with the dorsal pathway more involved in grapho-phonological conversion during phonological tasks, and the ventral pathway performing lexico-semantic access during semantic tasks. Furthermore, this subdivision is also suggested at the level of the inferior frontal cortex, involving ventral and dorsal parts for lexico-semantic and phonological processing, respectively. In the present study, we assessed inter-regional brain connectivity and task-induced modulations of brain activity during a phoneme detection and semantic categorization tasks, using fMRI in healthy subject. We used a dynamic causal modeling approach to assess inter-regional connectivity and task demand modulation within the dorsal and ventral pathways, including the following network components: the ventral occipito-temporal cortex (vOTC; dorsal and ventral), the superior temporal gyrus (STG; dorsal), the dorsal inferior frontal gyrus (dIFG; dorsal), and the ventral IFG (vIFG; ventral). We report three distinct inter-regional interactions supporting orthographic information transfer from vOTC to other language regions (vOTC -> STG, vOTC -> vIFG and vOTC -> dIFG) regardless of task demands. Moreover, we found that (a) during semantic processing (direct ventral pathway) the vOTC -> vIFG connection strength specifically increased and (b) a lack of modulation of the vOTC -> dIFG connection strength by the task that could suggest a more general involvement of the dorsal pathway during visual word recognition. Results are discussed in terms of anatomo-functional connectivity of visual word recognition network.

International audience; Rumination is predominantly experienced in the form of repetitive verbal thoughts. Verbal rumination is a particular case of inner speech. According to the Motor Simulation view, inner speech is a kind of motor action, recruiting the speech motor system. In this framework, we predicted an increase in speech muscle activity during rumination as compared to rest. We also predicted increased forehead activity, associated with anxiety during rumination. We measured electromyographic activity over the orbicularis oris superior and inferior, frontalis and flexor carpi radialis muscles. Results showed increased lip and forehead activity after rumination induction compared to an initial relaxed state, together with increased self-reported levels of rumination. Moreover, our data suggest that orofacial relaxation is more effective in reducing rumination than non-orofacial relaxation. Altogether, these results support the hypothesis that verbal rumination involves the speech motor system, and provide a promising psychophysiological index to assess the presence of verbal rumination.

Our goal was to apply a statistical approach to allow the identification of atypical language patterns and to differentiate patients with epilepsy from healthy subjects, based on their cerebral activity, as assessed by functional MRI (fMRI). Patients with focal epilepsy show reorganization or plasticity of brain networks involved in cognitive functions, inducing ‘atypical’ (compared to ‘typical’ in healthy people) brain profiles. Moreover, some of these patients suffer from drug-resistant epilepsy, and they undergo surgery to stop seizures. The neurosurgeon should only remove the zone generating seizures and must preserve cognitive functions to avoid deficits. To preserve functions, one should know how they are represented in the patient’s brain, which is in general different from that of healthy subjects. For this purpose, in the pre-surgical stage, robust and efficient methods are required to identify atypical from typical representations. Given the frequent location of regions generating seizures in the vicinity of language networks, one important function to be considered is language. The risk of language impairment after surgery is determined pre-surgically by mapping language networks. In clinical settings, cognitive mapping is classically performed with fMRI. The fMRI analyses allowing the identification of atypical patterns of language networks in patients are not sufficiently robust and require additional statistic approaches. In this study, we report the use of a statistical nonlinear machine learning classification, the Extreme Gradient Boosting (XGBoost) algorithm, to identify atypical patterns and classify 55 participants as healthy subjects or patients with epilepsy. XGBoost analyses were based on neurophysiological features in five language regions (three frontal and two temporal) in both hemispheres and activated with fMRI for a phonological (PHONO) and a semantic (SEM) language task. These features were combined into 135 cognitively plausible subsets and further submitted to selection and binary classification. Classification performance was scored with the Area Under the receiver operating characteristic curve (AUC). Our results showed that the subset SEM_LH BA_47-21 (left fronto-temporal activation induced by the SEM task) provided the best discrimination between the two groups (AUC of 91 ± 5%). The results are discussed in the framework of the current debates of language reorganization in focal epilepsy. Electronic supplementary material The online version of this article (doi:10.1007/s40708-017-0065-7) contains supplementary material, which is available to authorized users.

International audience; Deux conceptions de la nature de la parole intérieure s'opposent sur le plan théorique. Dans la lignée de la conception incarnée du langage, l'hypothèse de la Simulation Motrice conçoit la parole intérieure comme un acte moteur imaginé, simulé. Dans la conception mentaliste du langage, les tenants de l'hypothèse de l'Abstraction soutiennent que la parole intérieure est abstraite, appauvrie sur le plan articulatoire, voire amodale, et ne nécessite pas l'implication du système moteur. Prenant pour cas d'étude les ruminations mentales verbales, une forme de parole intérieure négative, répétitive, excessive et par conséquent abondante, nous proposons deux tests expérimentaux de ces hypothèses opposées. Le premier test examine si les ruminations mentales provoquées par un paradigme classique d'induction sont associées ou non à une activation motrice labiale, en mesurant l'activité électromyographique des lèvres. Le deuxième test évalue la contraposée de l'hypothèse de la Simulation Motrice, c'est-à-dire examine l'effet de la réduction de l'activité motrice orofaciale sur les ruminations, grâce à un protocole de relaxations ciblées. Nos résultats préliminaires semblent dans l'ensemble en faveur d'une nature incarnée et motrice des ruminations mentales. Le premier test montre en effet l'implication de la musculature labiale durant les ruminations. Le deuxième test suggère que le type de rumination induit par notre paradigme peut être réduit en relaxant spécifiquement les muscles de la parole, tels que les muscles des lèvres. Des études complémentaires sont envisagées pour confirmer ces résultats préliminaires, qui semblent soutenir l'hypothèse de la Simulation Motrice, selon laquelle la parole intérieure correspond à de la parole à voix haute simulée articulatoirement et inhibée avant l'exécution motrice.