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1.
Commun Biol ; 7(1): 506, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678058

RESUMO

Limb movement direction can be inferred from local field potentials in motor cortex during movement execution. Yet, it remains unclear to what extent intended hand movements can be predicted from brain activity recorded during movement planning. Here, we set out to probe the directional-tuning of oscillatory features during motor planning and execution, using a machine learning framework on multi-site local field potentials (LFPs) in humans. We recorded intracranial EEG data from implanted epilepsy patients as they performed a four-direction delayed center-out motor task. Fronto-parietal LFP low-frequency power predicted hand-movement direction during planning while execution was largely mediated by higher frequency power and low-frequency phase in motor areas. By contrast, Phase-Amplitude Coupling showed uniform modulations across directions. Finally, multivariate classification led to an increase in overall decoding accuracy (>80%). The novel insights revealed here extend our understanding of the role of neural oscillations in encoding motor plans.


Assuntos
Córtex Motor , Movimento , Humanos , Movimento/fisiologia , Masculino , Adulto , Córtex Motor/fisiologia , Feminino , Eletroencefalografia , Encéfalo/fisiologia , Adulto Jovem , Aprendizado de Máquina , Eletrocorticografia , Epilepsia/fisiopatologia , Mãos/fisiologia , Mapeamento Encefálico/métodos
2.
Front Behav Neurosci ; 17: 1141607, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37484522

RESUMO

Introduction: Emotion Regulation plays a crucial role in human's daily lives. Extensive research has shown that people with different attachment orientations exhibit divergencies in how they perform emotion regulation strategies. Methods: 44 adults performed an experimental emotion regulation task in which they were instructed to attend, reappraise, or suppress their emotions while viewing negative and neutral images taken from the International Affective Picture System (IAPS). Afterward, participants rated valence, arousal, and emotional dominance elicited by the images. Additionally, attachment orientations were measured using the ECR-12 questionnaire. Results: Results showed a relationship between attachment avoidance and the level of arousal during the reappraisal condition; specifically, the higher attachment avoidance levels, the greater the emotional intensity during the implementation of cognitive reappraisal strategy. Such results suggest an association between failing in downregulate intense emotions using cognitive reappraisal when there are higher levels of attachment avoidance. Consistently, we also found that lower dominance during reappraisal was associated with more levels of avoidance. Conclusion: These results indicate that people with higher levels of attachment avoidance experience difficulties when using the cognitive reappraisal strategy to reduce the emotional impact produced by negative emotional stimuli. Our findings reinforce the idea that avoidant people experience high physiological activation when experience emotions.

3.
J Vis Exp ; (193)2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36939245

RESUMO

The planning process, characterized by the capability to formulate an organized plan to reach a goal, is essential for human goal-directed behavior. Since planning is compromised in several neuropsychiatric disorders, the implementation of proper clinical and experimental tests to examine planning is critical. Due to the nature of the deployment of planning, in which several cognitive domains participate, the assessment of planning and the design of behavioral paradigms coupled with neuroimaging methods are current challenges in cognitive neuroscience. A planning task was evaluated in combination with an electroencephalogram (EEG) system and eye movement recordings in 27 healthy adult participants. Planning can be separated into two stages: a mental planning stage in which a sequence of steps is internally represented and an execution stage in which motor action is used to achieve a previously planned goal. Our protocol included a planning task and a control task. The planning task involved solving 36 maze trials, each representing a zoo map. The task had four periods: i) planning, where the subjects were instructed to plan a path to visit the locations of four animals according to a set of rules; ii) maintenance, where the subjects had to retain the planned path in their working memory; iii) execution, where the subjects used eye movements to trace the previously planned path as indicated by the eye-tracker system; and iv) response, where the subjects reported the order of the visited animals. The control task had a similar structure, but the cognitive planning component was removed by modifying the task goal. The spatial and temporal patterns of the EEG revealed that planning induces a gradual and lasting rise in frontal-midline theta activity (FMθ) over time. The source of this activity was identified within the prefrontal cortex by source analyses. Our results suggested that the experimental paradigm combining EEG and eye-tracker systems was optimal for evaluating cognitive planning.


Assuntos
Eletroencefalografia , Córtex Pré-Frontal , Adulto , Animais , Humanos , Córtex Pré-Frontal/fisiologia , Movimentos Oculares , Memória de Curto Prazo/fisiologia
4.
Front Hum Neurosci ; 17: 982849, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36816506

RESUMO

Studies showed that motor expertise was found to induce improvement in language processing. Grounded and situated approaches attributed this effect to an underlying automatic simulation of the motor experience elicited by action words, similar to motor imagery (MI), and suggest shared representations of action conceptualization. Interestingly, recent results also suggest that the mental simulation of action by MI training induces motor-system modifications and improves motor performance. Consequently, we hypothesize that, since MI training can induce motor-system modifications, it could be used to reinforce the functional connections between motor and language system, and could thus lead to improved language performance. Here, we explore these potential interactions by reviewing recent fundamental and clinical literature in the action-language and MI domains. We suggested that exploiting the link between action language and MI could open new avenues for complementary language improvement programs. We summarize the current literature to evaluate the rationale behind this novel training and to explore the mechanisms underlying MI and its impact on language performance.

5.
Ter. psicol ; 40(3): 367-395, dic. 2022. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1424679

RESUMO

La planificación es definida como la habilidad de desarrollar un plan secuenciado de pasos conductuales para alcanzar una meta y forma parte de un conjunto de funciones cognitivas de alto orden denominadas funciones ejecutivas. Esta función se ve afectada en diversas situaciones de la vida cotidiana y en una variedad de trastornos neuropsiquiátricos (por ej., depresión, ansiedad, déficit atencional, esquizofrenia, etc.). Tanto el diseño de pruebas cognitivas para evaluar planificación en el contexto clínico, como también el diseño de paradigmas experimentales de evaluación de la planificación en el contexto de investigación, continúa siendo un desafío para la neuropsicología clínica y para las neurociencias. En este artículo de revisión sistemática que sigue las direcciones PRISMA, revisamos la teoría e investigación en relación con la evaluación clínica y la investigación de las bases neurobiológicas de la planificación y los aportes a la comprensión de los mecanismos de su implementación. Se reportan medidas metodológicas comunes y se resumen las aproximaciones teóricas que contribuyen en su comprensión. Nuestros hallazgos muestran la implicancia de la corteza prefrontal en el rendimiento en planificación, en particular el área dorsolateral, corteza cingulada anterior y frontopolar. Mayores estudios clínicos, instrumentales y experimentales son necesarios para comprender mejor la planificación en el contexto de una teoría integrativa de las funciones ejecutivas y del rol de la corteza prefrontal.


Planning is defined as the ability to develop a sequenced plan of behavioral steps to achieve a goal and is part of a set of high-order cognitive functions called executive functions. This function is affected in various daily life situations and in a variety of neuropsychiatric disorders (e.g., depression, anxiety, attention deficit disorder, schizophrenia, etc.). Both the design of cognitive tests to assess planning in the clinical context, as well as the design of experimental paradigms for evaluating planning in research context, continues to be a challenge for clinical neuropsychology and neurosciences. In this PRISMA systematic review article, we review theory and research regarding clinical assessment and research into the neurobiological bases of planning and contributions to understanding the mechanisms of its implementation. Common methodological measures are reported and the theoretical approaches that contribute to their understanding are summarized. Our findings show the involvement of the prefrontal cortex in planning performance, particularly the dorsolateral area, the anterior cingulate cortex, and the frontopolar cortex. Further clinical, instrumental, and experimental studies are needed to better understand planning in the context of an integrative theory of executive functions and the role of the prefrontal cortex.


Assuntos
Humanos , Córtex Pré-Frontal/fisiologia , Função Executiva , Testes Neuropsicológicos
6.
J Neurosurg Case Lessons ; 4(22)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36443955

RESUMO

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.

7.
Brain Stimul ; 15(5): 1077-1087, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35952963

RESUMO

BACKGROUND: The exact architecture of the human auditory cortex remains a subject of debate, with discrepancies between functional and microstructural studies. In a hierarchical framework for sensory perception, simple sound perception is expected to take place in the primary auditory cortex, while the processing of complex, or more integrated perceptions is proposed to rely on associative and higher-order cortices. OBJECTIVES: We hypothesize that auditory symptoms induced by direct electrical stimulation (DES) offer a window into the architecture of the brain networks involved in auditory hallucinations and illusions. The intracranial recordings of these evoked perceptions of varying levels of integration provide the evidence to discuss the theoretical model. METHODS: We analyzed SEEG recordings from 50 epileptic patients presenting auditory symptoms induced by DES. First, using the Juelich cytoarchitectonic parcellation, we quantified which regions induced auditory symptoms when stimulated (ROI approach). Then, for each evoked auditory symptom type (illusion or hallucination), we mapped the cortical networks showing concurrent high-frequency activity modulation (HFA approach). RESULTS: Although on average, illusions were found more laterally and hallucinations more posteromedially in the temporal lobe, both perceptions were elicited in all levels of the sensory hierarchy, with mixed responses found in the overlap. The spatial range was larger for illusions, both in the ROI and HFA approaches. The limbic system was specific to the hallucinations network, and the inferior parietal lobule was specific to the illusions network. DISCUSSION: Our results confirm a network-based organization underlying conscious sound perception, for both simple and complex components. While symptom localization is interesting from an epilepsy semiology perspective, the hallucination-specific modulation of the limbic system is particularly relevant to tinnitus and schizophrenia.


Assuntos
Córtex Auditivo , Epilepsia , Ilusões , Estimulação Acústica , Córtex Auditivo/fisiologia , Mapeamento Encefálico , Estimulação Elétrica , Eletroencefalografia , Alucinações/etiologia , Humanos , Ilusões/fisiologia
8.
PLoS One ; 17(6): e0270352, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35749512

RESUMO

The objective of this study was to evaluate the effect of Motor Imagery (MI) training on language comprehension. In line with literature suggesting an intimate relationship between the language and the motor system, we proposed that a MI-training could improve language comprehension by facilitating lexico-semantic access. In two experiments, participants were assigned to a kinesthetic motor-imagery training (KMI) group, in which they had to imagine making upper-limb movements, or to a static visual imagery training (SVI) group, in which they had to mentally visualize pictures of landscapes. Differential impacts of both training protocols on two different language comprehension tasks (i.e., semantic categorization and sentence-picture matching task) were investigated. Experiment 1 showed that KMI training can induce better performance (shorter reaction times) than SVI training for the two language comprehension tasks, thus suggesting that a KMI-based motor activation can facilitate lexico-semantic access after only one training session. Experiment 2 aimed at replicating these results using a pre/post-training language assessment and a longer training period (four training sessions spread over four days). Although the improvement magnitude between pre- and post-training sessions was greater in the KMI group than in the SVI one on the semantic categorization task, the sentence-picture matching task tended to provide an opposite pattern of results. Overall, this series of experiments highlights for the first time that motor imagery can contribute to the improvement of lexical-semantic processing and could open new avenues on rehabilitation methods for language deficits.


Assuntos
Cinestesia , Semântica , Humanos , Imagens, Psicoterapia , Cinestesia/fisiologia , Idioma , Tempo de Reação
9.
PLoS One ; 16(7): e0254237, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34264980

RESUMO

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.


Assuntos
Função Executiva , Adulto , Compreensão , Humanos , Idioma
10.
Geroscience ; 43(4): 1725-1765, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33970414

RESUMO

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.


Assuntos
Reserva Cognitiva , Fatores Etários , Encéfalo
12.
Brain Imaging Behav ; 15(3): 1562-1579, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32761343

RESUMO

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.


Assuntos
Epilepsia do Lobo Temporal , Idioma , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética , Memória
13.
Neuroimage ; 226: 117557, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33189934

RESUMO

Cognitive planning, the ability to develop a sequenced plan to achieve a goal, plays a crucial role in human goal-directed behavior. However, the specific role of frontal structures in planning is unclear. We used a novel and ecological task, that allowed us to separate the planning period from the execution period. The spatio-temporal dynamics of EEG recordings showed that planning induced a progressive and sustained increase of frontal-midline theta activity (FMθ) over time. Source analyses indicated that this activity was generated within the prefrontal cortex. Theta activity from the right mid-Cingulate Cortex (MCC) and the left Anterior Cingulate Cortex (ACC) were correlated with an increase in the time needed for elaborating plans. On the other hand, left Frontopolar cortex (FP) theta activity exhibited a negative correlation with the time required for executing a plan. Since reaction times of planning execution correlated with correct responses, left FP theta activity might be associated with efficiency and accuracy in making a plan. Associations between theta activity from the right MCC and the left ACC with reaction times of the planning period may reflect high cognitive demand of the task, due to the engagement of attentional control and conflict monitoring implementation. In turn, the specific association between left FP theta activity and planning performance may reflect the participation of this brain region in successfully self-generated plans.


Assuntos
Cognição/fisiologia , Lobo Frontal/fisiologia , Giro do Cíngulo/fisiologia , Ritmo Teta/fisiologia , Pensamento/fisiologia , Adulto , Atenção , Eletroencefalografia , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Adulto Jovem
14.
Int J Psychophysiol ; 159: 23-36, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33159987

RESUMO

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/.


Assuntos
Cognição , Fala , Face , Feminino , Humanos , Estudantes
15.
Hum Brain Mapp ; 41(14): 4113-4126, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32697353

RESUMO

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.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiopatologia , Eletrocorticografia , Neuroestimuladores Implantáveis , Idioma , Rede Nervosa/fisiopatologia , Adulto , Córtex Cerebral/diagnóstico por imagem , Criança , Epilepsia Resistente a Medicamentos/fisiopatologia , Estimulação Elétrica , Epilepsias Parciais/fisiopatologia , Feminino , Humanos , Testes de Linguagem , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Estudos Retrospectivos , Adulto Jovem
16.
Sci Rep ; 10(1): 7870, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398733

RESUMO

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. In this work we train Random Forest classification models to decode eight perceptual categories from broad spectrum of human intracranial signals (4-150 Hz, 100 subjects) obtained during a visual perception task. We then analyze which of the spectral features the algorithm deemed relevant to the perceptual decoding and gain the insights into which parts of the recorded activity are actually characteristic of the visual categorization process in the human brain. 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. By focusing on task-relevant neural activity and separating it into dissociated anatomical and spectrotemporal groups we uncover spectral signatures that characterize neural mechanisms of visual category perception in human brain that have not yet been reported in the literature.


Assuntos
Epilepsia/fisiopatologia , Rede Nervosa/fisiologia , Desempenho Psicomotor/fisiologia , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Adulto , Algoritmos , Mapeamento Encefálico , Eletroencefalografia , Epilepsia/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Modelos Neurológicos , Rede Nervosa/diagnóstico por imagem , Estimulação Luminosa , Córtex Visual/diagnóstico por imagem , Adulto Jovem
17.
PLoS One ; 15(5): e0233282, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32459800

RESUMO

Although having a long history of scrutiny in experimental psychology, it is still controversial whether wilful inner speech (covert speech) production is accompanied by specific activity in speech muscles. We 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. 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 of testing the engagement of the speech motor system during wilful inner speech production.


Assuntos
Eletromiografia , Músculo Esquelético/fisiologia , Fonética , Pensamento/fisiologia , Encéfalo/fisiologia , Feminino , Humanos , Reconhecimento Automatizado de Padrão , Fala/fisiologia , Adulto Jovem
18.
J Neurosurg ; 134(3): 1251-1261, 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32330883

RESUMO

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.


Assuntos
Mapeamento Encefálico/métodos , Córtex Cerebral/fisiologia , Eletroencefalografia/métodos , Idioma , Estimulação Transcraniana por Corrente Contínua/métodos , Adolescente , Adulto , Córtex Cerebral/anatomia & histologia , Epilepsia Resistente a Medicamentos/cirurgia , Eletrocorticografia , Eletrodos Implantados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/anatomia & histologia , Rede Nervosa/fisiologia , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento , Adulto Jovem
19.
Cereb Cortex ; 30(7): 4011-4025, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32108230

RESUMO

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.


Assuntos
Adaptação Psicológica/fisiologia , Tomada de Decisões , Retroalimentação Psicológica/fisiologia , Feedback Formativo , Córtex Insular/fisiologia , Memória de Curto Prazo , Córtex Pré-Frontal/fisiologia , Adolescente , Adulto , Ritmo beta/fisiologia , Epilepsia Resistente a Medicamentos , Eletrocorticografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Leitura , Memória Espacial , Adulto Jovem
20.
Front Psychol ; 10: 2019, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31620039

RESUMO

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.

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