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1.
J Neurosci ; 43(40): 6779-6795, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37607822

RESUMO

Communication difficulties are one of the core criteria in diagnosing autism spectrum disorder (ASD), and are often characterized by speech reception difficulties, whose biological underpinnings are not yet identified. This deficit could denote atypical neuronal ensemble activity, as reflected by neural oscillations. Atypical cross-frequency oscillation coupling, in particular, could disrupt the joint tracking and prediction of dynamic acoustic stimuli, a dual process that is essential for speech comprehension. Whether such oscillatory anomalies already exist in very young children with ASD, and with what specificity they relate to individual language reception capacity is unknown. We collected neural activity data using electroencephalography (EEG) in 64 very young children with and without ASD (mean age 3; 17 females, 47 males) while they were exposed to naturalistic-continuous speech. EEG power of frequency bands typically associated with phrase-level chunking (δ, 1-3 Hz), phonemic encoding (low-γ, 25-35 Hz), and top-down control (ß, 12-20 Hz) were markedly reduced in ASD relative to typically developing (TD) children. Speech neural tracking by δ and θ (4-8 Hz) oscillations was also weaker in ASD compared with TD children. After controlling gaze-pattern differences, we found that the classical θ/γ coupling was replaced by an atypical ß/γ coupling in children with ASD. This anomaly was the single most specific predictor of individual speech reception difficulties in ASD children. These findings suggest that early interventions (e.g., neurostimulation) targeting the disruption of ß/γ coupling and the upregulation of θ/γ coupling could improve speech processing coordination in young children with ASD and help them engage in oral interactions.SIGNIFICANCE STATEMENT Very young children already present marked alterations of neural oscillatory activity in response to natural speech at the time of autism spectrum disorder (ASD) diagnosis. Hierarchical processing of phonemic-range and syllabic-range information (θ/γ coupling) is disrupted in ASD children. Abnormal bottom-up (low-γ) and top-down (low-ß) coordination specifically predicts speech reception deficits in very young ASD children, and no other cognitive deficit.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Masculino , Feminino , Humanos , Criança , Pré-Escolar , Fala/fisiologia , Transtorno do Espectro Autista/diagnóstico , Eletroencefalografia , Estimulação Acústica
2.
Eur J Public Health ; 34(Supplement_1): i58-i66, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946450

RESUMO

BACKGROUND: Despite concerns about worsening pregnancy outcomes resulting from healthcare restrictions, economic difficulties and increased stress during the COVID-19 pandemic, preterm birth (PTB) rates declined in some countries in 2020, while stillbirth rates appeared stable. Like other shocks, the pandemic may have exacerbated existing socioeconomic disparities in pregnancy, but this remains to be established. Our objective was to investigate changes in PTB and stillbirth by socioeconomic status (SES) in European countries. METHODS: The Euro-Peristat network implemented this study within the Population Health Information Research Infrastructure (PHIRI) project. A common data model was developed to collect aggregated tables from routine birth data for 2015-2020. SES was based on mother's educational level or area-level deprivation/maternal occupation if education was unavailable and harmonized into low, medium and high SES. Country-specific relative risks (RRs) of PTB and stillbirth for March to December 2020, adjusted for linear trends from 2015 to 2019, by SES group were pooled using random effects meta-analysis. RESULTS: Twenty-one countries provided data on perinatal outcomes by SES. PTB declined by an average 4% in 2020 {pooled RR: 0.96 [95% confidence intervals (CIs): 0.94-0.97]} with similar estimates across all SES groups. Stillbirths rose by 5% [RR: 1.05 (95% CI: 0.99-1.10)], with increases of between 3 and 6% across the three SES groups, with overlapping confidence limits. CONCLUSIONS: PTB decreases were similar regardless of SES group, while stillbirth rates rose without marked differences between groups.


Assuntos
COVID-19 , Nascimento Prematuro , SARS-CoV-2 , Natimorto , Humanos , Natimorto/epidemiologia , COVID-19/epidemiologia , Europa (Continente)/epidemiologia , Nascimento Prematuro/epidemiologia , Feminino , Gravidez , Adulto , Fatores Socioeconômicos , Pandemias , Classe Social , Disparidades nos Níveis de Saúde , Recém-Nascido , Resultado da Gravidez/epidemiologia , Disparidades Socioeconômicas em Saúde
3.
Cereb Cortex ; 30(11): 5717-5730, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32518940

RESUMO

Maternal voice is a highly relevant stimulus for newborns. Adult voice processing occurs in specific brain regions. Voice-specific brain areas in newborns and the relevance of an early vocal exposure on these networks have not been defined. This study investigates voice perception in newborns and the impact of prematurity on the cerebral processes. Functional magnetic resonance imaging (fMRI) and high-density electroencephalography (EEG) were used to explore the brain responses to maternal and stranger female voices in full-term newborns and preterm infants at term-equivalent age (TEA). fMRI results and the EEG oddball paradigm showed enhanced processing for voices in preterms at TEA than in full-term infants. Preterm infants showed additional cortical regions involved in voice processing in fMRI and a late mismatch response for maternal voice, considered as a first trace of a recognition process based on memory representation. Full-term newborns showed increased cerebral activity to the stranger voice. Results from fMRI, oddball, and standard auditory EEG paradigms highlighted important change detection responses to novelty after birth. These findings suggest that the main components of the adult voice-processing networks emerge early in development. Moreover, an early postnatal exposure to voices in premature infants might enhance their capacity to process voices.


Assuntos
Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Recém-Nascido Prematuro/fisiologia , Reconhecimento Psicológico/fisiologia , Voz , Mapeamento Encefálico/métodos , Eletroencefalografia/métodos , Feminino , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética/métodos , Masculino , Nascimento Prematuro
4.
Brain Topogr ; 31(3): 419-429, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29218677

RESUMO

The 40 Hz auditory steady-state response (ASSR) is a periodic response to a periodic stimulation. Its sources are located in the primary auditory cortex and the asymmetry of the planum temporale has previously been associated with hand preference and gender-related differences; thus subject's handedness and gender could potentially influence ASSRs. Nevertheless, electrophysiological studies of ASSRs are mainly dominated by right-handed participants and the observed findings can only be generalized to the right-handed populations. However, for a potential use of 40 Hz ASSR as a translational biomarker of neuropsychiatric disorders, it is important to investigate the response in association to handedness and gender. We included an equal number of left-handed and right-handed males and females and recorded EEG responses during left-ear, right-ear and both ears stimulation. The results of the study suggest that the processing of 40 Hz auditory stimulation depends on the subjects' gender and handedness: significantly lower phase-locking and strength of 40 Hz ASSRs were observed in left-handed females as compared to left-handed males, but right-handers did not differ in 40 Hz ASSRs. Our observation of the opposite impact of gender in the examined handedness groups stresses the importance of careful consideration of handedness and gender factors when evaluating the determinants of inter individual variability of 40 Hz ASSRs. This finding is of particular importance for clinical studies in psychiatry and neurology.


Assuntos
Potenciais Evocados Auditivos/fisiologia , Lateralidade Funcional/fisiologia , Lobo Temporal/fisiologia , Estimulação Acústica , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Fatores Sexuais , Adulto Jovem
5.
Exp Brain Res ; 232(4): 1267-81, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24496490

RESUMO

We investigate the contribution of both hemispheres in a lateralised lexical decision paradigm with emotional and neutral words in healthy volunteers. In a first experiment, high-density EEG analysis using source imaging methods revealed early specific participation of the temporoparietal junctions (TPJ) in both hemispheres for the detection of words. Then, in an event-related transcranial magnetic stimulation experiment with the same task, the disruption of left or right TPJ compared with a control stimulation over the vertex showed a slowing that is more pronounced when words are emotional and presented in the left visual field (LVF). This indicates that interference with both left and right TPJ results in impaired processing of words that were presented to the LVF. In addition, these results point to a specific cooperative contribution of the right hemisphere in the processing of words with emotional content compared with neutral words at very early stages. Results from the two experiments can be integrated in a brain-based spatiotemporal model of the early detection of written words.


Assuntos
Eletroencefalografia/métodos , Emoções/fisiologia , Lobo Parietal/fisiologia , Desempenho Psicomotor/fisiologia , Lobo Temporal/fisiologia , Estimulação Magnética Transcraniana/métodos , Adulto , Humanos , Masculino , Estimulação Luminosa/métodos , Adulto Jovem
6.
Brain Topogr ; 27(2): 258-70, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24026809

RESUMO

Several studies showed that in the human brain specific premotor and parietal areas are activated during the execution and observation of motor acts. The activation of this premotor-parietal network displaying the so-called Mirror Mechanism (MM) was proposed to underpin basic forms of action understanding. However, the functional properties of the MM in children are still largely unknown. In order to address this issue, we recorded high-density EEG from 12 children (6 female, 6 male; average age 10.5, SD ±2.15). Data were collected when children observed video clips showing hands grasping objects in two different experimental conditions: (1) Full Vision, in which the motor act was fully visible; (2) Hidden, in which the interaction between the hand and the object was not visible. Event-related potentials (ERPs) and topographic map analyses were used to investigate the temporal pattern of the ERPs and their brain source of localization, employing a children template of the Montreal Neurological Institute. Results showed that two different parieto-premotor circuits are activated by the observation of object-related hand reaching-to-grasping motor acts in children. The first circuit comprises the ventral premotor and the inferior parietal cortices. The second one comprises the dorsal premotor and superior parietal cortices. The activation of both circuits is differently lateralized and modulated in time, and influenced by the amount of visual information available about the hand grasping-related portion of the observed motor acts.


Assuntos
Potenciais Evocados Visuais , Lobo Frontal/fisiologia , Atividade Motora , Lobo Parietal/fisiologia , Criança , Eletroencefalografia , Feminino , Humanos , Masculino
7.
Biol Psychiatry ; 92(5): 407-418, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35550793

RESUMO

BACKGROUND: Numerous behavioral studies have highlighted the contribution of visual perceptual deficits to the nonverbal cognitive profile of individuals with 22q11.2 deletion syndrome. However, the neurobiological processes underlying these widespread behavioral alterations are yet to be fully understood. Thus, in this paper, we investigated the role of neural oscillations toward visuoperceptual deficits to elucidate the neurobiology of sensory impairments in deletion carriers. METHODS: We acquired 125 high-density electroencephalography recordings during a visual grating task in a group of 62 deletion carriers and 63 control subjects. Stimulus-elicited oscillatory responses were analyzed with 1) time-frequency analysis using wavelets decomposition at sensor and source level, 2) intertrial phase coherence, and 3) Granger causality connectivity in source space. Additional analyses examined the development of neural oscillations across age bins. RESULTS: Deletion carriers had decreased theta-band (4-8 Hz) and gamma-band (58-68 Hz) spectral power compared with control subjects in response to the visual stimuli, with an absence of age-related increase of theta- and gamma-band responses. Moreover, adult deletion carriers had decreased gamma- and theta-band responses but increased alpha/beta desynchronization (10-25 Hz) that correlated with behavioral performance. Granger causality estimates reflected an increased frontal-occipital connectivity in the beta range (22-40 Hz). CONCLUSIONS: Deletion carriers exhibited decreased theta- and gamma-band responses to visual stimuli, while alpha/beta desynchronization was preserved. Overall, the lack of age-related changes in deletion carriers implicates developmental impairments in circuit mechanisms underlying neural oscillations. The dissociation between the maturation of theta/gamma- and alpha/beta-band responses may indicate a selective impairment in supragranular cortical layers, leading to compensatory top-down connectivity.


Assuntos
Síndrome de DiGeorge , Ritmo Gama , Adulto , Eletroencefalografia , Ritmo Gama/fisiologia , Humanos , Percepção Visual/fisiologia
8.
Am J Psychiatry ; 179(3): 204-215, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35236117

RESUMO

OBJECTIVE: Brain oscillations play a pivotal role in synchronizing responses of local and global ensembles of neurons. Patients with schizophrenia exhibit impairments in oscillatory response, which are thought to stem from abnormal maturation during critical developmental stages. Studying individuals at genetic risk for psychosis, such as 22q11.2 deletion carriers, from childhood to adulthood may provide insights into developmental abnormalities. METHODS: The authors acquired 106 consecutive T1-weighted MR images and 40-Hz auditory steady-state responses (ASSRs) with high-density (256 channel) EEG in a group of 58 22q11.2 deletion carriers and 48 healthy control subjects. ASSRs were analyzed with 1) time-frequency analysis using Morlet wavelet decomposition, 2) intertrial phase coherence (ITPC), and 3) theta-gamma phase-amplitude coupling estimated in the source space between brain regions activated by the ASSRs. Additionally, volumetric analyses were performed with FreeSurfer. Subanalyses were conducted in deletion carriers who endorsed psychotic symptoms and in subgroups with different age bins. RESULTS: Deletion carriers had decreased theta and late-latency 40-Hz ASSRs and phase synchronization compared with control subjects. Deletion carriers with psychotic symptoms displayed a further reduction of gamma-band response, decreased ITPC, and decreased top-down modulation of gamma-band response in the auditory cortex. Reduced gamma-band response was correlated with the atrophy of auditory cortex in individuals with psychotic symptoms. In addition, a linear increase of theta and gamma power from childhood to adulthood was found in control subjects but not in deletion carriers. CONCLUSIONS: The results suggest that while all deletion carriers exhibit decreased gamma-band response, more severe local and long-range communication abnormalities are associated with the emergence of psychotic symptoms and gray matter loss. Additionally, the lack of age-related changes in deletion carriers indexes a potential developmental impairment in circuits underlying the maturation of neural oscillations during adolescence. The progressive disruption of gamma-band response in 22q11.2 deletion syndrome supports a developmental perspective toward understanding and treating psychotic disorders.


Assuntos
Córtex Auditivo , Síndrome de DiGeorge , Transtornos Psicóticos , Esquizofrenia , Adolescente , Criança , Eletroencefalografia , Humanos , Transtornos Psicóticos/genética , Esquizofrenia/diagnóstico , Adulto Jovem
9.
Schizophr Bull ; 47(1): 189-196, 2021 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-32747926

RESUMO

The 22q11.2 deletion syndrome (22q11.2 DS), one of the highest genetic risk for the development of schizophrenia, offers a unique opportunity to understand neurobiological and functional changes preceding the onset of the psychotic illness. Reduced auditory mismatch negativity response (MMN) has been proposed as a promising index of abnormal sensory processing and brain pathology in schizophrenia. However, the link between the MMN response and its underlying cerebral mechanisms in 22q11.2 DS remains unexamined. We measured auditory-evoked potentials to frequency deviant stimuli with high-density electroencephalogram and volumetric estimates of cortical and thalamic auditory areas with structural T1-weighted magnetic resonance imaging in a sample of 130 individuals, 70 with 22q11.2 DS and 60 age-matched typically developing (TD) individuals. Compared to TD group, the 22q11.2 deletion carriers reveal reduced MMN response and significant changes in topographical maps and decreased gray matter volumes of cortical and subcortical auditory areas, however, without any correlations between MMN alteration and structural changes. Furthermore, exploratory research on the presence of hallucinations (H+\H-) reveals no change in MMN response in 22q11.2DS (H+ and H-) as compared to TD individuals. Nonetheless, we observe bilateral volume reduction of the superior temporal gyrus and left medial geniculate in 22q11.2DSH+ as compared to 22q11.2DSH- and TD participants. These results suggest that the mismatch response might be a promising neurophysiological marker of functional changes within the auditory pathways that might underlie elevated risk for the development of psychotic symptoms.


Assuntos
Córtex Auditivo , Percepção Auditiva/fisiologia , Síndrome de DiGeorge , Potenciais Evocados Auditivos/fisiologia , Corpos Geniculados , Alucinações , Adolescente , Adulto , Córtex Auditivo/diagnóstico por imagem , Córtex Auditivo/patologia , Córtex Auditivo/fisiopatologia , Criança , Síndrome de DiGeorge/diagnóstico por imagem , Síndrome de DiGeorge/patologia , Síndrome de DiGeorge/fisiopatologia , Eletroencefalografia , Feminino , Corpos Geniculados/diagnóstico por imagem , Corpos Geniculados/patologia , Corpos Geniculados/fisiopatologia , Alucinações/diagnóstico por imagem , Alucinações/patologia , Alucinações/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
10.
Commun Biol ; 4(1): 968, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34400754

RESUMO

Autism spectrum disorders (ASD) are associated with disruption of large-scale brain network. Recently, we found that directed functional connectivity alterations of social brain networks are a core component of atypical brain development at early developmental stages in ASD. Here, we investigated the spatio-temporal dynamics of whole-brain neuronal networks at a subsecond scale in 113 toddlers and preschoolers (66 with ASD) using an EEG microstate approach. We first determined the predominant microstates using established clustering methods. We identified five predominant microstate (labeled as microstate classes A-E) with significant differences in the temporal dynamics of microstate class B between the groups in terms of increased appearance and prolonged duration. Using Markov chains, we found differences in the dynamic syntax between several maps in toddlers and preschoolers with ASD compared to their TD peers. Finally, exploratory analysis of brain-behavioral relationships within the ASD group suggested that the temporal dynamics of some maps were related to conditions comorbid to ASD during early developmental stages.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Mapeamento Encefálico , Encéfalo/fisiopatologia , Vias Neurais/fisiopatologia , Pré-Escolar , Feminino , Humanos , Lactente , Masculino
11.
Lancet Reg Health Eur ; 8: 100167, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34557855

RESUMO

BACKGROUND: To inform the on-going debate about the use of universal prescriptive versus national intrauterine growth charts, we compared perinatal mortality for small and large-for-gestational-age (SGA/LGA) infants according to international and national charts in Europe. METHODS: We classified singleton births from 33 to 42 weeks of gestation in 2010 and 2014 from 15 countries (N = 1,475,457) as SGA (birthweight <10th percentile) and LGA (>90th percentile) using the international Intergrowth-21st newborn standards and national charts based on the customised charts methodology. We computed sex-adjusted odds ratios (aOR) for stillbirth, neonatal and extended perinatal mortality by this classification using multilevel models. FINDINGS: SGA and LGA prevalence using national charts were near 10% in all countries, but varied according to international charts with a north to south gradient (3.0% to 10.1% and 24.9% to 8.0%, respectively). Compared with appropriate for gestational age (AGA) infants by both charts, risk of perinatal mortality was increased for SGA by both charts (aOR[95% confidence interval (CI)]=6.1 [5.6-6.7]) and infants reclassified by international charts from SGA to AGA (2.7 [2.3-3.1]), but decreased for those reclassified from AGA to LGA (0.6 [0.4-0.7]). Results were similar for stillbirth and neonatal death. INTERPRETATION: Using international instead of national charts in Europe could lead to growth restricted infants being reclassified as having normal growth, while infants with low risks of mortality could be reclassified as having excessive growth. FUNDING: InfAct Joint Action, CHAFEA Grant n°801,553 and EU/EFPIA Innovative Medicines Initiative 2 Joint Undertaking ConcePTION grant n°821,520. AH received a PhD grant from EHESP.

12.
Wellcome Open Res ; 6: 21, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722933

RESUMO

Preterm birth is the leading cause of infant death worldwide, but the causes of preterm birth are largely unknown. During the early COVID-19 lockdowns, dramatic reductions in preterm birth were reported; however, these trends may be offset by increases in stillbirth rates. It is important to study these trends globally as the pandemic continues, and to understand the underlying cause(s). Lockdowns have dramatically impacted maternal workload, access to healthcare, hygiene practices, and air pollution - all of which could impact perinatal outcomes and might affect pregnant women differently in different regions of the world. In the international Perinatal Outcomes in the Pandemic (iPOP) Study, we will seize the unique opportunity offered by the COVID-19 pandemic to answer urgent questions about perinatal health. In the first two study phases, we will use population-based aggregate data and standardized outcome definitions to: 1) Determine rates of preterm birth, low birth weight, and stillbirth and describe changes during lockdowns; and assess if these changes are consistent globally, or differ by region and income setting, 2) Determine if the magnitude of changes in adverse perinatal outcomes during lockdown are modified by regional differences in COVID-19 infection rates, lockdown stringency, adherence to lockdown measures, air quality, or other social and economic markers, obtained from publicly available datasets. We will undertake an interrupted time series analysis covering births from January 2015 through July 2020. The iPOP Study will involve at least 121 researchers in 37 countries, including obstetricians, neonatologists, epidemiologists, public health researchers, environmental scientists, and policymakers. We will leverage the most disruptive and widespread "natural experiment" of our lifetime to make rapid discoveries about preterm birth. Whether the COVID-19 pandemic is worsening or unexpectedly improving perinatal outcomes, our research will provide critical new information to shape prenatal care strategies throughout (and well beyond) the pandemic.

13.
Neuroimage ; 44(1): 190-9, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18793732

RESUMO

Voluntarily directing visual attention to a cued position in space leads to improved processing of forthcoming visual stimuli at the attended position, and attenuated processing of competing stimuli elsewhere, due to anticipatory tuning of visual cortex activity. In EEG, recent evidence points to a determining role of modulations of posterior alpha-band activity (8-14 Hz) in such anticipatory facilitation (alpha-power decreases) versus inhibition (alpha-power increases). Yet, while such alpha-modulations are a common finding, the direction of modulation varies to a great extent across studies implying dependence on task demands. Here, we reveal opposite modulation of posterior alpha-power with early/initiation versus later/sustained processes of anticipatory attention orienting. Marked alpha-decreases were observed during shifting of attention (initial 700 ms) over occipito-parietal areas processing to-be-attended visual space, while alpha-increases dominated in the subsequent maintenance phase (>700 ms) over occipito-parietal cortex tuned to unattended positions. Notably, the presence of alpha-modulation strongly depended on individual resting alpha-power. Overall, this provides further support to an active facilitative versus inhibitory role of alpha-power decreases and increases and suggests that these attention-related changes are differentially deployed during anticipatory attention orienting to prepare versus maintain the cortex for optimal target processing.


Assuntos
Ritmo alfa , Atenção/fisiologia , Mapeamento Encefálico , Encéfalo/fisiologia , Percepção Espacial/fisiologia , Adulto , Sinais (Psicologia) , Eletroculografia , Potenciais Evocados Visuais/fisiologia , Feminino , Humanos , Masculino , Estimulação Luminosa
14.
Front Psychiatry ; 10: 582, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507462

RESUMO

Background: Atypical neural processing of social visual information contributes to impaired social cognition in autism spectrum disorder. However, evidence for early developmental alterations in neural processing of social contingencies is scarce. Most studies in the literature have been conducted in older children and adults. Here, we aimed to investigate alterations in neural processing of social visual information in children with autism spectrum disorder compared to age-matched typically developing peers. Methods: We used a combination of 129-channel electroencephalography and high-resolution eye-tracking to study differences in the neural processing of dynamic cartoons containing human-like social interactions between 14 male children with autism spectrum disorder and 14 typically developing male children, aged 2-5 years. Using a microstate approach, we identified four prototypical maps in both groups and compared the temporal characteristics and inverse solutions (activation of neural sources) of these maps between groups. Results: Inverse solutions of the group maps that were most dominant during free viewing of the dynamic cartoons indicated decreased prefrontal and cingulate activation, impaired activation of the premotor cortex, and increased activation of parietal, temporal, occipital, and cerebellar regions in children with autism spectrum disorder compared to their typically developing peers. Conclusions: Our findings suggest that impairments in brain regions involved in processing social contingencies embedded in dynamic cartoons are present from an early age in autism spectrum disorder. To the best of our knowledge, this is the first study to investigate neural processing of social interactions of children with autism spectrum disorder using dynamic semi-naturalistic stimuli.

15.
Transl Psychiatry ; 9(1): 138, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30992427

RESUMO

The 22q11.2 Deletion Syndrome (22q11.2 DS) is one of the highest genetic risk factors for the development of schizophrenia spectrum disorders. In schizophrenia, reduced amplitude of the frequency mismatch negativity (fMMN) has been proposed as a promising neurophysiological marker for progressive brain pathology. In this longitudinal study in 22q11.2 DS, we investigate the progression of fMMN between childhood and adolescence, a vulnerable period for brain maturation. We measured evoked potentials to auditory oddball stimuli in the same sample of 16 patients with 22q11.2 DS and 14 age-matched controls in childhood and adolescence. In addition, we cross-sectionally compared an increased sample of 51 participants with 22q11.2 DS and 50 controls divided into two groups (8-14 and 14-20 years). The reported results are obtained using the fMMN difference waveforms. In the longitudinal design, the 22q11.2 deletion carriers exhibit a significant reduction in amplitude and a change in topographic patterns of the mismatch negativity response from childhood to adolescence. The same effect, reduced mismatch amplitude in adolescence, while preserved during childhood, is observed in the cross-sectional study. These results point towards functional changes within the brain network responsible for the fMMN. In addition, the adolescents with 22q11.2 DS displayed a significant increase in amplitude over central electrodes during the auditory N1 component. No such differences, reduced mismatch response nor increased N1, were observed in the typically developing group. These findings suggest different developmental trajectories of early auditory sensory processing in 22q11.2 DS and functional changes that emerge during the critical period of increased risk for schizophrenia spectrum disorders.


Assuntos
Síndrome de DiGeorge/complicações , Síndrome de DiGeorge/patologia , Potenciais Evocados Auditivos , Lobo Frontal/fisiopatologia , Lateralidade Funcional , Estimulação Acústica , Adolescente , Criança , Estudos Transversais , Progressão da Doença , Eletroencefalografia , Feminino , Humanos , Estudos Longitudinais , Masculino , Esquizofrenia/etiologia
16.
Neuroreport ; 19(2): 203-8, 2008 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-18185109

RESUMO

Variations of oscillatory brain activity have been related to distinct functional states depending on the frequency of oscillations. In the alpha-band (about 8-14 Hz), decreased oscillatory activity is thought to reflect a state of enhanced cortical excitability, and increased activity to reflect a state of cortical idling or inhibition in which excitability is reduced, but the alpha/excitability link has not been probed directly. Here, we studied the relationship between resting oscillatory activity and visual cortex excitability across participants using electroencephalography and transcranial magnetic stimulation to the occipital pole. We found individual posterior alpha-band power to correlate with the individual threshold for eliciting illusory, transcranial magnetic stimulation-induced visual percepts. This provides direct support for an alpha/excitability link and for baseline states of the visual brain to vary across individuals.


Assuntos
Ritmo alfa , Relógios Biológicos/fisiologia , Potenciais Evocados Visuais/fisiologia , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Adulto , Mapeamento Encefálico , Eletroencefalografia , Feminino , Humanos , Ilusões/fisiologia , Masculino , Testes Neuropsicológicos , Estimulação Luminosa , Limiar Sensorial/fisiologia , Estimulação Magnética Transcraniana , Córtex Visual/anatomia & histologia
17.
Neuroimage Clin ; 17: 976-986, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29527499

RESUMO

Carriers of the rare 22q11.2 microdeletion present with a high percentage of positive and negative symptoms and a high genetic risk for schizophrenia. Visual processing impairments have been characterized in schizophrenia, but less so in 22q11.2 Deletion Syndrome (DS). Here, we focus on visual processing using high-density EEG and source imaging in 22q11.2DS participants (N = 25) and healthy controls (N = 26) with an illusory contour discrimination task. Significant differences between groups emerged at early and late stages of visual processing. In 22q11.2DS, we first observed reduced amplitudes over occipital channels and reduced source activations within dorsal and ventral visual stream areas during the P1 (100-125 ms) and within ventral visual cortex during the N1 (150-170 ms) visual evoked components. During a later window implicated in visual completion (240-285 ms), we observed an increase in global amplitudes in 22q11.2DS. The increased surface amplitudes for illusory contours at this window were inversely correlated with positive subscales of prodromal symptoms in 22q11.2DS. The reduced activity of ventral and dorsal visual areas during early stages points to an impairment in visual processing seen both in schizophrenia and 22q11.2DS. During intervals related to perceptual closure, the inverse correlation of high amplitudes with positive symptoms suggests that participants with 22q11.2DS who show an increased brain response to illusory contours during the relevant window for contour processing have less psychotic symptoms and might thus be at a reduced prodromal risk for schizophrenia.


Assuntos
Síndrome de DiGeorge/complicações , Transtornos da Visão/etiologia , Adolescente , Adulto , Análise de Variância , Mapeamento Encefálico , Correlação de Dados , Eletroencefalografia , Potenciais Evocados Visuais/fisiologia , Feminino , Humanos , Masculino , Estimulação Luminosa , Sintomas Prodrômicos , Tempo de Reação/fisiologia , Índice de Gravidade de Doença , Fatores de Tempo , Transtornos da Visão/diagnóstico , Percepção Visual/fisiologia , Adulto Jovem
18.
Elife ; 72018 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-29482718

RESUMO

Social impairments are a hallmark of Autism Spectrum Disorders (ASD), but empirical evidence for early brain network alterations in response to social stimuli is scant in ASD. We recorded the gaze patterns and brain activity of toddlers with ASD and their typically developing peers while they explored dynamic social scenes. Directed functional connectivity analyses based on electrical source imaging revealed frequency specific network atypicalities in the theta and alpha frequency bands, manifesting as alterations in both the driving and the connections from key nodes of the social brain associated with autism. Analyses of brain-behavioural relationships within the ASD group suggested that compensatory mechanisms from dorsomedial frontal, inferior temporal and insular cortical regions were associated with less atypical gaze patterns and lower clinical impairment. Our results provide strong evidence that directed functional connectivity alterations of social brain networks is a core component of atypical brain development at early stages of ASD.


Newborns are attracted to voices, faces and social gestures. Paying attention to these social cues in everyday life helps infants and young children learn how to interact with others. During this period of development, a network of connections forms between different parts of the brain that helps children to understand other people's social behaviors. During their first year of life, infants who later develop autism spectrum disorders (ASD) pay less attention to social cues. This early indifference to these important signals leads to social deficits in children with ASD. They are less able to understand other people's behaviors or engage in typical social interactions. It's not yet clear why children with ASD are less attuned to social cues. But is likely that the development of brain networks essential for understanding social behavior suffers as a result. Studying how such networks develop in typical very young children and those with ASD may help scientist learn more. Now, Sperdin et al. confirm there are differences in the social brain-networks of very young children with ASD compared with their typical peers. In the experiment, 3-year-old children with ASD and without watched videos of other children playing, while Sperdin et al. recorded what they looked at and what happened in their brains. Eyemovements were measured with a tracker, and the brain activity was recorded using an electroencephalogram (EEG), which uses sensors placed on the scalp to measure electrical signals. What children with ASD looked at was different than their typical peers, and these differences corresponded with alterations in the brain networks that process social information. Children with ASD who had less severe symptoms had stronger activity in these brain networks. What they looked at also was more similar to typical children. This suggests less severely affected children with ASD may be able to compensate that way. Identifying ASD-like behaviors and brain differences early in life may help scientists to better understand what causes the condition. It may also help clinicians provide more individualized therapies early in life when the brain is most adaptable. Long-term studies of these brain-network differences in children with ASD are necessary to better understand how therapies can influence these changes.


Assuntos
Transtorno Autístico/fisiopatologia , Encéfalo/patologia , Rede Nervosa/patologia , Comportamento Social , Mapeamento Encefálico , Criança , Pré-Escolar , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
19.
Neuroimage Clin ; 16: 545-556, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28971006

RESUMO

Gaze conveys emotional information, and humans present sensitivity to its direction from the earliest days of life. Bipolar disorder is a disease characterized by fluctuating states of emotional and cognitive dysregulation. To explore the role of attentional control on face processing in bipolar patients (BP) we used gaze direction as an emotion modulation parameter in a two-back Working Memory (WM) task while high-density EEG data were acquired. Since gaze direction influences emotional attributions to faces with neutral expressions as well, we presented neutral faces with direct and averted gaze. Nineteen euthymic BP and a sample of age- and gender-matched controls were examined. In BP we observed diminished P200 and augmented P300 evoked responses, differentially modulated by non-repeated or repeated faces, as well as by gaze direction. BP showed a reduced P200 amplitude, significantly stronger for faces with direct gaze than averted gaze. Source localization of P200 indicated decreased activity in sensory-motor regions and frontal areas suggestive of abnormal affective processing of neutral faces. The present study provides neurophysiological evidence for abnormal gaze processing in BP and suggests dysfunctional processing of direct eye contact as a prominent characteristic of bipolar disorder.


Assuntos
Transtorno Bipolar/fisiopatologia , Encéfalo/fisiopatologia , Fixação Ocular/fisiologia , Adulto , Atenção/fisiologia , Eletroencefalografia , Emoções/fisiologia , Potenciais Evocados Visuais/fisiologia , Expressão Facial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Percepção Visual/fisiologia
20.
Psychiatry Res Neuroimaging ; 269: 62-72, 2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-28941875

RESUMO

Humans are sensitive to gaze direction from early life, and gaze has social and affective values. Borderline personality disorder (BPD) is a clinical condition characterized by emotional dysregulation and enhanced sensitivity to affective and social cues. In this study we wanted to investigate the temporal-spatial dynamics of spontaneous gaze processing in BPD. We used a 2-back-working-memory task, in which neutral faces with direct and averted gaze were presented. Gaze was used as an emotional modulator of event-related-potentials to faces. High density EEG data were acquired in 19 females with BPD and 19 healthy women, and analyzed with a spatio-temporal microstates analysis approach. Independently of gaze direction, BPD patients showed altered N170 and P200 topographies for neutral faces. Source localization revealed that the anterior cingulate and other prefrontal regions were abnormally activated during the N170 component related to face encoding, while middle temporal deactivations were observed during the P200 component. Post-task affective ratings showed that BPD patients had difficulty to disambiguate neutral gaze. This study provides first evidence for an early neural bias toward neutral faces in BPD independent of gaze direction and also suggests the importance of considering basic aspects of social cognition in identifying biological risk factors of BPD.


Assuntos
Transtorno da Personalidade Borderline/fisiopatologia , Eletroencefalografia/métodos , Expressão Facial , Fixação Ocular/fisiologia , Neuroimagem/métodos , Percepção Visual/fisiologia , Adolescente , Adulto , Transtorno da Personalidade Borderline/diagnóstico , Transtorno da Personalidade Borderline/psicologia , Mapeamento Encefálico/métodos , Emoções/fisiologia , Potenciais Evocados/fisiologia , Feminino , Giro do Cíngulo/fisiologia , Humanos , Estimulação Luminosa/métodos , Adulto Jovem
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