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OBJECTIVE: Some studies have hypothesized that atypical neural synchronization at the delta frequency band in the auditory cortex is associated with phonological and language skills in children with Autism Spectrum Disorder (ASD), but it is still poorly understood. This study investigated this neural activity and addressed the relationships between auditory response and behavioral measures of children with ASD. METHODS: We used magnetoencephalography and individual brain models to investigate 2 Hz Auditory Steady-State Response (ASSR) in 20 primary-school-aged children with ASD and 20 age-matched typically developing (TD) controls. RESULTS: First, we found a between-group difference in the localization of the auditory response, so as the topology of 2 Hz ASSR was more superior and posterior in TD children when comparing to children with ASD. Second, the power of 2 Hz ASSR was reduced in the ASD group. Finally, we observed a significant association between the amplitude of neural response and language skills in children with ASD. CONCLUSIONS: The study provided the evidence of reduced neural response in children with ASD and its relation to language skills. SIGNIFICANCE: These findings may inform future interventions targeting auditory and language impairments in ASD population.
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Recent studies have shown a growing interest in the so-called "aperiodic" component of the EEG power spectrum, which describes the overall trend of the whole spectrum with a linear or exponential function. In the field of brain aging, this aperiodic component is associated both with age-related changes and performance on cognitive tasks. This study aims to elucidate the potential role of education in moderating the relationship between resting-state EEG features (including aperiodic component) and cognitive performance in aging. N = 179 healthy participants of the "Leipzig Study for Mind-Body-Emotion Interactions" (LEMON) dataset were divided into three groups based on age and education. Older adults exhibited lower exponent, offset (i.e. measures of aperiodic component), and Individual Alpha Peak Frequency (IAPF) as compared to younger adults. Moreover, visual attention and working memory were differently associated with the aperiodic component depending on education: in older adults with high education, higher exponent predicted slower processing speed and less working memory capacity, while an opposite trend was found in those with low education. While further investigation is needed, this study shows the potential modulatory role of education in the relationship between the aperiodic component of the EEG power spectrum and aging cognition.
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Envelhecimento , Cognição , Eletroencefalografia , Humanos , Cognição/fisiologia , Masculino , Feminino , Idoso , Envelhecimento/fisiologia , Adulto , Pessoa de Meia-Idade , Memória de Curto Prazo/fisiologia , Adulto Jovem , Encéfalo/fisiologia , Escolaridade , Atenção/fisiologia , Idoso de 80 Anos ou maisRESUMO
OBJECTIVES: Cancer-related cognitive impairment (CRCI) refers to a cognitive decline associated with cancer or its treatments. While research into CRCI is expanding, evidence remains scattered due to differences in study designs, methodologies, and definitions. The present umbrella review aims to provide a comprehensive overview of the current evidence regarding the impact of different breast cancer therapies on cognitive functioning, with a particular focus on the interplay among objective cognitive deficits (ie, measured with standardized tests), subjective cognitive concerns, (ie, self-reported), and other mediating psycho-physical factors. METHODS: The search was made in Pubmed, Embase, and Scopus for articles published until July 2023, following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analysis protocol. RESULTS: Chemotherapy and endocrine therapy appear consistently associated with CRCI in patients with breast cancer, primarily affecting memory, attention/concentration, executive functioning, and processing speed. Subjective cognitive concerns were often found weakly or not associated with neuropsychological test results, while overall CRCI seemed consistently associated with psychological distress, fatigue, sleep quality, and inflammatory and biological factors. CONCLUSION: Current evidence suggests that CRCI is common after chemotherapy and endocrine therapy for breast cancer. However, heterogeneity in study designs and the scarcity of studies on more recent treatments such as targeted therapies and immunotherapies, highlight the need for more systematic and harmonized studies, possibly taking into account the complex and multifactorial etiology of CRCI. This may provide valuable insights into CRCI's underlying mechanisms and potential new ways to treat it.
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Neoplasias da Mama , Disfunção Cognitiva , Humanos , Neoplasias da Mama/psicologia , Neoplasias da Mama/complicações , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/terapia , Feminino , Disfunção Cognitiva/etiologiaRESUMO
The present work investigates whether financial abilities can be associated with numerical abilities and with general cognitive abilities. We compared performance on numerical and financial tests, and on tests routinely used to measure general cognitive performance, in healthy controls and in a group of people with heterogeneous pathological conditions including mild cognitive impairment, amyotrophic lateral sclerosis, traumatic brain injury, and schizophrenia. Patients showed lower performances in both numerical and financial abilities compared to controls. Numerical and financial skills were positively correlated in both groups, but they correlated poorly with measures of general cognitive functioning. Crucially, only basic financial tasks -such as counting currencies- but not advanced ones -like financial judgments- were associated with numerical or general cognitive functioning in logistic regression analyses. Conversely, advanced financial abilities, but not basic ones, were associated with abstract reasoning. At a qualitative analysis, we found that deficits in numerical and financial abilities might double dissociate. Similarly, we observed double dissociations between difficulties in financial abilities and cognitive deficits. In conclusion, financial abilities may be independent of numerical skills, and financial deficits are not always related to the presence of cognitive difficulties. These findings are important for both clinical and legal practice.
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The neurobiology of Autism Spectrum Disorder (ASD) is hypothetically related to the imbalance between neural excitation (E) and inhibition (I). Different studies have revealed that alpha-band (8-12 Hz) activity in magneto- and electroencephalography (MEG and EEG) may reflect E and I processes and, thus, can be of particular interest in ASD research. Previous findings indicated alterations in event-related and baseline alpha activity in different cortical systems in individuals with ASD, and these abnormalities were associated with core and co-occurring conditions of ASD. However, the knowledge on auditory alpha oscillations in this population is limited. This MEG study investigated stimulus-induced (Event-Related Desynchronization, ERD) and baseline alpha-band activity (both periodic and aperiodic) in the auditory cortex and also the relationships between these neural activities and behavioral measures of children with ASD. Ninety amplitude-modulated tones were presented to two groups of children: 20 children with ASD (5 girls, Mage = 10.03, SD = 1.7) and 20 typically developing controls (9 girls, Mage = 9.11, SD = 1.3). Children with ASD had a bilateral reduction of alpha-band ERD, reduced baseline aperiodic-adjusted alpha power, and flattened aperiodic exponent in comparison to TD children. Moreover, lower raw baseline alpha power and aperiodic offset in the language-dominant left auditory cortex were associated with better language skills of children with ASD measured in formal assessment. The findings highlighted the alterations of E / I balance metrics in response to basic auditory stimuli in children with ASD and also provided evidence for the contribution of low-level processing to language difficulties in ASD.
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Estimulação Acústica , Ritmo alfa , Córtex Auditivo , Transtorno do Espectro Autista , Magnetoencefalografia , Humanos , Transtorno do Espectro Autista/fisiopatologia , Feminino , Córtex Auditivo/fisiopatologia , Masculino , Criança , Ritmo alfa/fisiologia , Potenciais Evocados Auditivos/fisiologia , Percepção Auditiva/fisiologia , EletroencefalografiaRESUMO
Verb generation is among the most frequently used tasks in presurgical mapping. Because this task involves many processes, the overall brain effects are not specific. While it is necessary to identify the whole network involving noun comprehension or semantic retrieval and lexical selection to produce the verb, isolation of those components is also crucial. Here, we present data from four patients undergoing presurgical brain mapping. The study implied a reanalysis of magnetoencephalography data with a recategorization of the used items. It aimed to extract the task component that relies on the inferior frontal gyrus (IFG). The task could be applied with higher specificity when targeting frontal areas. For that, we based item classification on the selection demands imposed by the noun. It is a robust finding that the IFG carries out this selection and that a quantitative index can be calculated for each noun, which depends on the selection effort (Proceedings of the National Academy of Sciences of the United States of America, 1997; 94(26):14792-14797, Proceedings of the National Academy of Sciences of the United States of America, 1998; 95(26):15855-15860). Data showed focality and specificity, with a correlation between this derived index and source activations in the inferior frontal gyrus for all patients. Strikingly, we detected when the right-hemisphere homologue area was involved in the selection process in two patients showing reorganization or language right lateralization. The present data are a step towards a dissection of broad specific tasks frequently used in presurgical protocols.
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Idioma , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Semântica , Encéfalo/diagnóstico por imagem , Encéfalo/cirurgia , Mapeamento Encefálico/métodosRESUMO
OBJECTIVES: The aim of this review is to provide an overview on prevalence and clinical tools for the diagnosis of apathy, as well as on neurophysiological and neuroimaging findings obtained from studies in patients with apathy in different forms of dementia, including Alzheimer's disease (AD), vascular (VaD) and mixed dementia, frontotemporal dementia (FTD), and Parkinson's disease dementia (PDD). METHODS: Randomized controlled trials, non-randomized controlled trials, controlled before-after studies, and interrupted time series from four databases (WebOfScience, Scopus, Pubmed, and PsycINFO) addressing apathy in adults or older people aged over 65 years of age affected by dementia were included. RESULTS: The prevalence of apathy was 26-82% for AD, 28.6-91.7 for VaD, 29-97.5% in PDD, and 54.8-88.0 in FTD. The assessment of apathy was not consistent in the reviewed studies. Methylphenidate was the most successful pharmacological treatment for apathy. Neurobiological studies highlighted the relationship between both structural and functional brain areas and the presence or severity of apathy. CONCLUSION: Apathy is a very common disorder in all types of dementia, although it is often underdiagnosed and undertreated. Further studies are needed to investigate its diagnosis and management. A consensus on the different evaluation scales should be achieved.
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Doença de Alzheimer , Apatia , Demência Frontotemporal , Doença de Parkinson , Humanos , Idoso , Apatia/fisiologia , Demência Frontotemporal/diagnóstico por imagem , Demência Frontotemporal/epidemiologia , Demência Frontotemporal/terapia , PrevalênciaRESUMO
BACKGROUND: The maintenance of an intention in memory (Prospective Memory, PM) while performing a task is associated with a cost in terms of both performance (longer response times and lower accuracy) and neurophysiological modulations, which extent depends on several features of the stimuli. AIM: This study explores the neural patterns associated with PM in different sensory modalities, to identify differences depending on this variable and discuss their functional meaning. METHOD: Data were collected using a High-Density EEG during a baseline and a PM condition, proposed in a visual and an auditory version. Theta and alpha oscillations were compared between the two conditions within each modality using a cluster-based permutation approach. RESULTS: PM conditions were associated with clusters of decreased alpha and theta activity in both modalities. However, different spatiotemporal dynamics were elicited as a function of sensory modality: alpha decreases displayed an overlapping onset between modalities, but different durations, lasting longer in the auditory modality. Conversely, the clusters of decreased theta activity presented similar durations between modalities, but different temporal and spatial onsets, appearing at different moments over the respective sensory areas. CONCLUSIONS: The similar spatiotemporal properties of alpha suppression between modalities indicate that such oscillations may represent a supramodal, top-down process, presumably reflecting the external direction of attention to successfully detect the prospective cue (strategic monitoring). In theta, the clusters showed more modality-specific differences, which temporal and spatial properties correspond to the ones necessary to perform the ongoing task, suggesting a shift in resource allocation in favor of the PM task.
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Memória Episódica , Humanos , Ritmo Teta/fisiologia , Tempo de Reação/fisiologia , Intenção , EletroencefalografiaRESUMO
Non-invasive brain stimulation (NIBS) techniques, including transcranial magnetic stimulation (TMS) and transcranial electrical stimulation (tES), have provided valuable insights into the role of the cerebellum in cognitive processes. However, replicating findings from studies involving cerebellar stimulation poses challenges. This meta-analysis investigates the impact of NIBS on cognitive processes associated with the cerebellum. We conducted a systematic search and analyzed 66 studies and 91 experiments involving healthy adults who underwent either TMS or transcranial direct current stimulation (tDCS) targeting the cerebellum. The results indicate that anodal tDCS applied to the medial cerebellum enhances cognitive performance. In contrast, high-frequency TMS disrupts cognitive performance when targeting the lateral cerebellar hemispheres or when employed in online protocols. Similarly, low-frequency TMS and continuous theta burst stimulation (cTBS) diminish performance in offline protocols. Moreover, high-frequency TMS impairs accuracy. By identifying consistent effects and moderators of modulation, this meta-analysis contributes to improving the replicability of studies using NIBS on the cerebellum and provides guidance for future research aimed at developing effective NIBS interventions targeting the cerebellum.
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Estimulação Transcraniana por Corrente Contínua , Adulto , Humanos , Estimulação Transcraniana por Corrente Contínua/métodos , Estimulação Magnética Transcraniana/métodos , Cerebelo/fisiologia , Cognição/fisiologiaRESUMO
Alpha-band (8-12 Hz) event-related desynchronization (ERD) or a decrease in alpha power in electro- and magnetoencephalography (EEG and MEG) reflects the involvement of a neural tissue in information processing. It is known that most children with autism spectrum disorder (ASD) have difficulties in information processing, and, thus, investigation of alpha oscillations is of particular interest in this population. Previous studies have demonstrated alterations in this neural activity in individuals with ASD; however, little is known about alpha ERD during simultaneous presentation of auditory and visual stimuli in children with and without ASD. As alpha oscillations are intimately related to attention, and attention deficit is one of the common co-occurring conditions of ASD, we predict that children with ASD can have altered alpha ERD in one of the sensory domains. In the present study, we used MEG to investigate alpha ERD in groups of 20 children with ASD and 20 age-matched typically developing controls. Simple amplitude-modulated tones were presented together with a fixation cross appearing on the screen. The results showed that children with ASD had a bilateral reduction in alpha-band ERD in the auditory but not visual cortex. Moreover, alterations in the auditory cortex were associated with a higher presence of autistic traits measured in behavioral assessment.
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(i) Background: Cognitive impairment in people with multiple sclerosis (MS) has been studied in relation to certain clinical variables (e.g., motor disability and disease duration) and lifestyle factors such as cognitive reserve (CR). However, only very few studies have considered the interaction of clinical variables and cognitive reserve in preserving the integrity of the neuropsychological profile. In this paper, we hypothesised that a higher level of CR might predict good cognitive efficiency by modulating the clinical outcome of the disease. (ii) Methods: A sample of 100 participants with MS (age range 30-74), was recruited and assessed remotely with a questionnaire to measure CR and a cognitive screening test. Data were analysed through generalized additive models. (iii) Results: We found that the model analysing the interaction between CR and disease duration, and between CR and motor disability, was able to explain a significant percentage of cognitive performance. In particular, higher levels of CR predicted a better cognitive performance despite a long disease duration, unless the motor disability was severe. (iv) Conclusion: This study highlights the crucial role of CR in modulating cognitive efficiency in people with MS.
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The posterior superior temporal sulcus (pSTS) is a critical node in a network specialized for perceiving emotional facial expressions that is reciprocally connected with early visual cortices (V1/V2). Current models of perceptual decision-making increasingly assign relevance to recursive processing for visual recognition. However, it is unknown whether inducing plasticity into reentrant connections from pSTS to V1/V2 impacts emotion perception. Using a combination of electrophysiological and neurostimulation methods, we demonstrate that strengthening the connectivity from pSTS to V1/V2 selectively increases the ability to perceive facial expressions associated with emotions. This behavior is associated with increased electrophysiological activity in both these brain regions, particularly in V1/V2, and depends on specific temporal parameters of stimulation that follow Hebbian principles. Therefore, we provide evidence that pSTS-to-V1/V2 back-projections are instrumental to perception of emotion from facial stimuli and functionally malleable via manipulation of associative plasticity.
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Emoções , Percepção Visual , Eletrofisiologia Cardíaca , Face , Reconhecimento PsicológicoRESUMO
Cortical excitability is commonly measured by applying magnetic stimulation in combination with measuring behavioral response. This measure has, however, some shortcomings including spatial limitation to the primary motor cortex and not accounting for intrinsic excitability fluctuations. Here, we use a measure for intrinsic excitability based on phase synchronization previously validated for epilepsy. We apply this measure in 30 healthy participants' magnetoencephalography (MEG) recordings during the exposure of auditory white noise, a stimulus that has been suggested to modify cortical excitability. Using cortical parcellation of the MEG source data, we could find a specific pattern of increased and decreased excitability while participants are exposed to white noise vs. silence. Specifically, excitability during white noise exposure decreases in the frontal lobe and increases in the temporal lobe. This study thus adds to the understanding of cortical excitability changes due to specific environmental stimuli as well as the spatial extent of these effects.
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Anticipatory mechanisms are known to play a key role in language, but they have been mostly investigated with violation paradigms, which only consider what happens after predictions have been (dis)confirmed. Relatively few studies focused on the pre-stimulus interval and found that stronger expectations are associated with lower pre-stimulus alpha power. However, alpha power also fluctuates spontaneously, in the absence of experimental manipulations; and in the attention and perception domains, spontaneously low pre-stimulus power is associated with better behavioral performance and with event-related potential (ERPs) with shorter latencies and higher amplitudes. Importantly, little is known about the role of alpha fluctuations in other domains, as it is in language. To this aim, we investigated whether spontaneous fluctuations in pre-stimulus alpha power modulate language-related ERPs in a semantic congruence task. Electrophysiology data were analyzed using Generalized Additive Mixed Models to model nonlinear interactions between pre-stimulus alpha power and EEG amplitude, at the single-trial level. We found that the N400 and the late posterior positivity/P600 were larger in the case of lower pre-stimulus alpha power. Still, while the N400 was observable regardless of the level of pre-stimulus power, a late posterior positivity/P600 effect was only observable for low pre-stimulus alpha power. We discuss these findings in light of the different, albeit connected, functional interpretations of pre-stimulus alpha and the ERPs according to both a nonpredictive interpretation focused on attentional mechanisms and under a predictive processing framework.
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Eletroencefalografia , Potenciais Evocados , Humanos , Masculino , Feminino , Potenciais Evocados/fisiologia , Compreensão/fisiologia , Idioma , SemânticaRESUMO
Background: Stroke is a debilitating disease affecting millions of people worldwide. Despite the survival rate has significantly increased over the years, many stroke survivors are left with severe impairments impacting their quality of life. Rehabilitation programs have proved to be successful in improving the recovery process. However, a reliable model of sensorimotor recovery and a clear identification of predictive markers of rehabilitation-induced recovery are still needed. This article introduces the cross-modality protocols designed to investigate the rehabilitation treatment's effect in a group of stroke survivors. Methods/design: A total of 75 stroke patients, admitted at the IRCCS San Camillo rehabilitation Hospital in Venice (Italy), will be included in this study. Here, we describe the rehabilitation programs, clinical, neuropsychological, and physiological/imaging [including electroencephalography (EEG), transcranial magnetic stimulation (TMS), and magnetic resonance imaging (MRI) techniques] protocols set up for this study. Blood collection for the characterization of predictive biological biomarkers will also be taken. Measures derived from data acquired will be used as candidate predictors of motor recovery. Discussion/summary: The integration of cutting-edge physiological and imaging techniques, with clinical and cognitive assessment, dose of rehabilitation and biological variables will provide a unique opportunity to define a predictive model of recovery in stroke patients. Taken together, the data acquired in this project will help to define a model of rehabilitation induced sensorimotor recovery, with the final aim of developing personalized treatments promoting the greatest chance of recovery of the compromised functions.
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Objectives: In healthy aging, the way people cope differently with cognitive and neural decline is influenced by exposure to cognitively enriching life-experiences. Education is one of them, so that in general, the higher the education, the better the expected cognitive performance in aging. At the neural level, it is not clear yet how education can differentiate resting state functional connectivity profiles and their cognitive underpinnings. Thus, with this study, we aimed to investigate whether the variable education allowed for a finer description of age-related differences in cognition and resting state FC. Methods: We analyzed in 197 healthy individuals (137 young adults aged 20-35 and 60 older adults aged 55-80 from the publicly available LEMON database), a pool of cognitive and neural variables, derived from magnetic resonance imaging, in relation to education. Firstly, we assessed age-related differences, by comparing young and older adults. Then, we investigated the possible role of education in outlining such differences, by splitting the group of older adults based on their education. Results: In terms of cognitive performance, older adults with higher education and young adults were comparable in language and executive functions. Interestingly, they had a wider vocabulary compared to young adults and older adults with lower education. Concerning functional connectivity, the results showed significant age- and education-related differences within three networks: the Visual-Medial, the Dorsal Attentional, and the Default Mode network (DMN). For the DMN, we also found a relationship with memory performance, which strengthen the evidence that this network has a specific role in linking cognitive maintenance and FC at rest in healthy aging. Discussion: Our study revealed that education contributes to differentiating cognitive and neural profiles in healthy older adults. Also, the DMN could be a key network in this context, as it may reflect some compensatory mechanisms relative to memory capacities in older adults with higher education.
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Tele-neuropsychology, i.e., the application of remote audio-visual technologies to neuropsychological evaluation or rehabilitation, has become increasingly popular and widespread during and after the COVID-19 pandemic. New tools with updated normative data and appropriate methodological developments are necessary. We present Tele-GEMS, a telephone-based cognitive screening developed on N = 601 Italian participants. It yields a global score tapping on orientation, memory, spatial representation, language, and pragmatic abilities. Its administration lasts about 10 min. Clinical cut-offs are provided, accounting for demographic variables (age, education, and sex) and also for a comprehensive index taking into account cognitively stimulating life experiences that can build up a cognitive reserve. Tele-GEMS shows good internal consistency and a good inter-rater agreement. The test includes the thresholds for estimating a significant change after repeated measurements. Tele-GEMS has a good construct validity as assessed with MoCA and a suitable criterion validity assessed with its in-person version (GEMS). All the materials and the instructions, including scripts and an online Application for the automatic calculation of cut-offs, are accessible on OSF at https://osf.io/t3bma/ under a Creative Commons license.
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Testes Neuropsicológicos , Psicometria , Telemedicina , Humanos , Masculino , Feminino , Gravidez , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Telefone , Psicometria/métodosRESUMO
BACKGROUND: Magnetoencephalography (MEG) is a widely used non-invasive tool to estimate brain activity with high temporal resolution. However, due to the ill-posed nature of the MEG source imaging (MSI) problem, the ability of MSI to identify accurately underlying brain sources along the cortical surface is still uncertain and requires validation. METHOD: We validated the ability of MSI to estimate the background resting state activity of 45 healthy participants by comparing it to the intracranial EEG (iEEG) atlas (https://mni-open-ieegatlas. RESEARCH: mcgill.ca/). First, we applied wavelet-based Maximum Entropy on the Mean (wMEM) as an MSI technique. Next, we converted MEG source maps into intracranial space by applying a forward model to the MEG-reconstructed source maps, and estimated virtual iEEG (ViEEG) potentials on each iEEG channel location; we finally quantitatively compared those with actual iEEG signals from the atlas for 38 regions of interest in the canonical frequency bands. RESULTS: The MEG spectra were more accurately estimated in the lateral regions compared to the medial regions. The regions with higher amplitude in the ViEEG than in the iEEG were more accurately recovered. In the deep regions, MEG-estimated amplitudes were largely underestimated and the spectra were poorly recovered. Overall, our wMEM results were similar to those obtained with minimum norm or beamformer source localization. Moreover, the MEG largely overestimated oscillatory peaks in the alpha band, especially in the anterior and deep regions. This is possibly due to higher phase synchronization of alpha oscillations over extended regions, exceeding the spatial sensitivity of iEEG but detected by MEG. Importantly, we found that MEG-estimated spectra were more comparable to spectra from the iEEG atlas after the aperiodic components were removed. CONCLUSION: This study identifies brain regions and frequencies for which MEG source analysis is likely to be reliable, a promising step towards resolving the uncertainty in recovering intracerebral activity from non-invasive MEG studies.
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Eletrocorticografia , Magnetoencefalografia , Humanos , Magnetoencefalografia/métodos , Eletrocorticografia/métodos , Encéfalo , Mapeamento Encefálico/métodos , Eletroencefalografia/métodosRESUMO
Background: The ability to perceive two tactile stimuli as asynchronous can be measured using the somatosensory temporal discrimination threshold (STDT). In healthy humans, the execution of a voluntary movement determines an increase in STDT values, while the integration of STDT and movement execution is abnormal in patients with basal ganglia disorders. Sensorimotor integration can be modulated using focal muscle vibration (fMV), a neurophysiological approach that selectively activates proprioceptive afferents from the vibrated muscle. Method: In this study, we investigated whether fMV was able to modulate STDT or STDT-movement integration in healthy subjects by measuring them before, during and after fMV applied over the first dorsalis interosseous, abductor pollicis brevis and flexor radialis carpi muscles. Results: The results showed that fMV modulated STDT-movement integration only when applied over the first dorsalis interosseous, namely, the muscle performing the motor task involved in STDT-movement integration. These changes occurred during and up to 10 min after fMV. Differently, fMV did not influence STDT at rest. We suggest that that fMV interferes with the STDT-movement task processing, possibly disrupting the physiological processing of sensory information. Conclusions: This study showed that FMV is able to modulate STDT-movement integration when applied over the muscle involved in the motor task. This result provides further information on the mechanisms underlying fMV, and has potential future implications in basal ganglia disorders characterized by altered sensorimotor integration.
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The discovery that human brain connectivity data can be used as a "fingerprint" to identify a given individual from a population, has become a burgeoning research area in the neuroscience field. Recent studies have identified the possibility to extract these brain signatures from the temporal rich dynamics of resting-state magneto encephalography (MEG) recordings. Nevertheless, it is still uncertain to what extent MEG signatures can serve as an indicator of human identifiability during task-related conduct. Here, using MEG data from naturalistic and neurophysiological tasks, we show that identification improves in tasks relative to resting-state, providing compelling evidence for a task dependent axis of MEG signatures. Notably, improvements in identifiability were more prominent in strictly controlled tasks. Lastly, the brain regions contributing most towards individual identification were also modified when engaged in task activities. We hope that this investigation advances our understanding of the driving factors behind brain identification from MEG signals.