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1.
Sci Rep ; 11(1): 17595, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34475457

RESUMO

Pandemics such as the Covid-19 pandemic have shown to impact our physical and mental well-being, with particular challenges for children and families. We describe data from 43 adults (31♀, ages = 22-51; 21 mothers) and 26 children (10♀, ages = 7-17 years) including pre-pandemic brain function and seven assessment points during the first months of the pandemic. We investigated (1) changes in child and adult well-being, (2) mother-child associations of mental well-being, and (3) associations between pre-pandemic brain activation during mentalizing and later fears or burden. In adults the prevalence of clinically significant anxiety-levels was 34.88% and subthreshold depression 32.56%. Caregiver burden in parents was moderately elevated. Overall, scores of depression, anxiety, and caregiver burden decreased across the 11 weeks after Covid-19-onset. Children's behavioral and emotional problems during Covid-19 did not significantly differ from pre-pandemic levels and decreased during restrictions. Mothers' subjective burden of care was associated with children's emotional and behavioral problems, while depression levels in mothers were related to children's mood. Furthermore, meeting friends was a significant predictor of children's mood during early restrictions. Pre-pandemic neural correlates of mentalizing in prefrontal regions preceded later development of fear of illnesses and viruses in all participants, while temporoparietal activation preceded higher subjective burden in mothers.


Assuntos
Ansiedade , COVID-19 , Depressão , Imageamento por Ressonância Magnética , Saúde Mental , Pandemias , SARS-CoV-2 , Estresse Psicológico , Adolescente , Adulto , Ansiedade/diagnóstico por imagem , Ansiedade/epidemiologia , Ansiedade/psicologia , COVID-19/diagnóstico por imagem , COVID-19/epidemiologia , COVID-19/psicologia , Criança , Depressão/diagnóstico por imagem , Depressão/epidemiologia , Depressão/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estresse Psicológico/diagnóstico por imagem , Estresse Psicológico/epidemiologia , Estresse Psicológico/psicologia
2.
Eur Neuropsychopharmacol ; 49: 40-53, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33813055

RESUMO

Conduct Disorder (CD) is characterized by severe aggressive and antisocial behavior. The stress hormone system has frequently been investigated as a neurobiological correlate of CD, while other interacting neuroendocrine biomarkers of sex hormone or neuropeptide systems have rarely been studied, especially in females. We examined multiple basal neuroendocrine biomarkers in female and male adolescents with CD compared to healthy controls (HCs), and explored whether they mediate effects of environmental risk factors on CD. Within the FemNAT-CD study, salivary cortisol, alpha-amylase, testosterone, dehydroepiandrosterone-sulfate (DHEA-S), estradiol, progesterone, oxytocin, and arginine-vasopressin were measured under basal conditions in 166 pubertal adolescents with CD, and 194 sex-, age-, and puberty-matched HCs (60% females, 9-18 years). Further, environmental risk factors were assessed. Single hormone analyses showed higher DHEA-S, and lower estradiol and progesterone levels in both females and males with CD relative to HCs. When accounting for interactions between neuroendocrine systems, a male-specific sex hormone factor (testosterone/DHEA-S) predicted male CD, while estradiol and a stress-system factor (cortisol/alpha-amylase) interacting with oxytocin predicted female CD. Estradiol, progesterone, and oxytocin partly explained associations between early environmental risk and CD. Findings provide evidence for sex-specific associations between basal neuroendocrine measures and CD. Especially altered sex hormones (androgen increases in males, estrogen reductions in females) robustly related to CD, while basal stress-system measures did not. Early environmental risk factors for CD may act partly through their effects on the neuroendocrine system, especially in females. Limitations (e.g., basal neuroendocrine assessment, different sample sizes per sex, pubertal participants, exploratory mediation analyses) are discussed.

3.
Neuroimage Clin ; 29: 102519, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33316763

RESUMO

BACKGROUND: Conduct disorder (CD) is characterized by severe aggressive and antisocial behavior. Initial evidence suggests neural deficits and aberrant eye gaze pattern during emotion processing in CD; both concepts, however, have not yet been studied simultaneously. The present study assessed the functional brain correlates of emotional face processing with and without consideration of concurrent eye gaze behavior in adolescents with CD compared to typically developing (TD) adolescents. METHODS: 58 adolescents (23CD/35TD; average age = 16 years/range = 14-19 years) underwent an implicit emotional face processing task. Neuroimaging analyses were conducted for a priori-defined regions of interest (insula, amygdala, and medial orbitofrontal cortex) and using a full-factorial design assessing the main effects of emotion (neutral, anger, fear), group and the interaction thereof (cluster-level, p < .05 FWE-corrected) with and without consideration of concurrent eye gaze behavior (i.e., time spent on the eye region). RESULTS: Adolescents with CD showed significant hypo-activations during emotional face processing in right anterior insula compared to TD adolescents, independent of the emotion presented. In-scanner eye-tracking data revealed that adolescents with CD spent significantly less time on the eye, but not mouth region. Correcting for eye gaze behavior during emotional face processing reduced group differences previously observed for right insula. CONCLUSIONS: Atypical insula activation during emotional face processing in adolescents with CD may partly be explained by attentional mechanisms (i.e., reduced gaze allocation to the eyes, independent of the emotion presented). An increased understanding of the mechanism causal for emotion processing deficits observed in CD may ultimately aid the development of personalized intervention programs.


Assuntos
Transtorno da Conduta , Reconhecimento Facial , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Transtorno da Conduta/diagnóstico por imagem , Emoções , Expressão Facial , Fixação Ocular , Humanos , Imageamento por Ressonância Magnética , Adulto Jovem
4.
Artigo em Inglês | MEDLINE | ID: mdl-31311717

RESUMO

BACKGROUND: Conduct disorder (CD), which is characterized by severe aggressive and antisocial behavior, is linked to emotion processing and regulation deficits. However, the neural correlates of emotion regulation are yet to be investigated in adolescents with CD. Furthermore, it remains unclear whether CD is associated with deficits in emotional reactivity, emotion regulation, or both. METHODS: We used functional magnetic resonance imaging to study effortful emotion regulation by cognitive reappraisal in 59 female adolescents 15 to 18 years of age (30 with a CD diagnosis and 29 typically developing (TD) control adolescents). RESULTS: Behaviorally, in-scanner self-report ratings confirmed successful emotion regulation within each group individually but significant group differences in emotional reactivity and reappraisal success when comparing the groups (CD < TD). Functional magnetic resonance imaging results revealed significantly lower activation in left dorsolateral prefrontal cortex and angular gyrus in CD compared with TD adolescents during emotion regulation, but no group differences for emotional reactivity. Furthermore, connectivity between left dorsolateral prefrontal cortex and the bilateral putamen, right prefrontal cortex, and amygdala was reduced in CD compared with TD adolescents during reappraisal. Callous-unemotional traits were unrelated to neural activation, but these traits correlated negatively with behavioral reports of emotional reactivity. CONCLUSIONS: Our results demonstrate reduced prefrontal brain activity and functional connectivity during effortful emotion regulation in female adolescents with CD. This sheds light on the neural basis of the behavioral deficits that have been reported previously. Future studies should investigate whether cognitive interventions are effective in enhancing emotion-regulation abilities and/or normalizing prefrontal and temporoparietal activity in female adolescents with CD.


Assuntos
Transtorno da Conduta/fisiopatologia , Conectoma , Regulação Emocional/fisiologia , Córtex Pré-Frontal/fisiopatologia , Adolescente , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiopatologia , Transtorno da Conduta/diagnóstico por imagem , Feminino , Hipocampo/diagnóstico por imagem , Hipocampo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Lobo Occipital/diagnóstico por imagem , Lobo Occipital/fisiopatologia , Córtex Pré-Frontal/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Tálamo/fisiopatologia
5.
Dev Cogn Neurosci ; 34: 82-91, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30103188

RESUMO

Phonological processing has been postulated as a core area of deficit among children with dyslexia. Reduced brain activation during phonological processing in children with dyslexia has been observed in left-hemispheric temporoparietal regions. Musical training has shown positive associations with phonological processing abilities, but the neural mechanisms underlying this relationship remain unspecified. The present research aims to distinguish neural correlates of phonological processing in school-age typically developing musically trained children, musically untrained children, and musically untrained children with dyslexia utilizing fMRI. A whole-brain ANCOVA, accounting for gender and nonverbal cognitive abilities, identified a main effect of group in bilateral temporoparietal regions. Subsequent region-of-interest analyses replicated temporoparietal hypoactivation in children with dyslexia relative to typically developing children. By contrast, musically trained children showed greater bilateral activation in temporoparietal regions when compared to each musically untrained group. Therefore, musical training shows associations with enhanced bilateral activation of left-hemispheric regions known to be important for reading. Findings suggest that engagement of these regions through musical training may underlie the putative positive effects of music on reading development. This supports the hypothesis that musical training may facilitate the development of a bilateral compensatory neural network, which aids children with atypical function in left-hemispheric temporoparietal regions.


Assuntos
Encéfalo/fisiologia , Dislexia/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Música/psicologia , Fonética , Adolescente , Criança , Feminino , Humanos , Masculino
6.
Neuroimage Clin ; 17: 856-864, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29527490

RESUMO

Callous-unemotional traits are characterized by a lack of empathy, a disregard for others' feelings and shallow or deficient affect, such as a lack of remorse or guilt. Neuroanatomical correlates of callous-unemotional traits have been demonstrated in clinical samples (i.e., adolescents with disruptive behavior disorders). However, it is unknown whether callous-unemotional traits are associated with neuroanatomical correlates within normative populations without clinical levels of aggression or antisocial behavior. Here we investigated the relationship between callous-unemotional traits and gray matter volume using voxel-based morphometry in a large sample of typically-developing boys and girls (N = 189). Whole-brain multiple regression analyses controlling for site, total intracranial volume, and age were conducted in the whole sample and in boys and girls individually. Results revealed that sex and callous-unemotional traits interacted to predict gray matter volume when considering the whole sample. This interaction was driven by a significant positive correlation between callous-unemotional traits and bilateral anterior insula volume in boys, but not girls. Insula gray matter volume explained 19% of the variance in callous-unemotional traits for boys. Our results demonstrate that callous-unemotional traits are related to variations in brain structure beyond psychiatric samples. This association was observed for boys only, underlining the importance of considering sex as a factor in future research designs. Future longitudinal studies should determine whether these findings hold over childhood and adolescence, and whether the neuroanatomical correlates of callous-unemotional traits are predictive of future psychiatric vulnerability. General scientific summary: This study suggests that callous-unemotional traits have a neuroanatomical correlate within typically developing boys, but not girls. Bilateral anterior insula volume explains up to 19% of the variance in callous-unemotional traits in boys.


Assuntos
Transtorno da Personalidade Antissocial/patologia , Encéfalo/patologia , Transtorno da Conduta/patologia , Emoções , Empatia , Caracteres Sexuais , Adolescente , Transtorno da Personalidade Antissocial/diagnóstico por imagem , Transtorno da Personalidade Antissocial/psicologia , Encéfalo/diagnóstico por imagem , Criança , Transtorno da Conduta/diagnóstico por imagem , Transtorno da Conduta/psicologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Escalas de Graduação Psiquiátrica , Psicometria , Análise de Regressão
7.
J Am Acad Child Adolesc Psychiatry ; 56(3): 258-265.e1, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28219492

RESUMO

OBJECTIVE: Diffusion tensor imaging (DTI) studies in adolescent conduct disorder (CD) have demonstrated white matter alterations of tracts connecting functionally distinct fronto-limbic regions, but only in boys or mixed-gender samples. So far, no study has investigated white matter integrity in girls with CD on a whole-brain level. Therefore, our aim was to investigate white matter alterations in adolescent girls with CD. METHOD: We collected high-resolution DTI data from 24 girls with CD and 20 typically developing control girls using a 3T magnetic resonance imaging system. Fractional anisotropy (FA) and mean diffusivity (MD) were analyzed for whole-brain as well as a priori-defined regions of interest, while controlling for age and intelligence, using a voxel-based analysis and an age-appropriate customized template. RESULTS: Whole-brain findings revealed white matter alterations (i.e., increased FA) in girls with CD bilaterally within the body of the corpus callosum, expanding toward the right cingulum and left corona radiata. The FA and MD results in a priori-defined regions of interest were more widespread and included changes in the cingulum, corona radiata, fornix, and uncinate fasciculus. These results were not driven by age, intelligence, or attention-deficit/hyperactivity disorder comorbidity. CONCLUSION: This report provides the first evidence of white matter alterations in female adolescents with CD as indicated through white matter reductions in callosal tracts. This finding enhances current knowledge about the neuropathological basis of female CD. An increased understanding of gender-specific neuronal characteristics in CD may influence diagnosis, early detection, and successful intervention strategies.


Assuntos
Transtorno da Conduta/diagnóstico por imagem , Corpo Caloso/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adolescente , Criança , Imagem de Tensor de Difusão , Feminino , Humanos
8.
Cereb Cortex ; 27(1): 764-776, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26585334

RESUMO

Early language delay has often been associated with atypical language/literacy development. Neuroimaging studies further indicate functional disruptions during language and print processing in school-age children with a retrospective report of early language delay. Behavioral data of 114 5-year-olds with a retrospective report of early language delay in infancy (N = 34) and those without (N = 80) and with a familial risk for dyslexia and those without are presented. Behaviorally, children with a retrospective report of early language delay exhibited reduced performance in language/reading-related measures. A voxel-based morphometry analysis in a subset (N = 46) demonstrated an association between reduced gray matter volume and early language delay in left-hemispheric middle temporal, occipital, and frontal regions. Alterations in middle temporal cortex in children with a retrospective report of early language delay were observed regardless of familial risk for dyslexia. Additionally, while children with isolated familial risk for dyslexia showed gray matter reductions in temporoparietal and occipitotemporal regions, these effects were most profound in children with both risk factors. An interaction effect of early language delay and familial risk was revealed in temporoparietal, occipital, and frontal cortex. Our findings support a cumulative effect of early behavioral and genetic risk factors on brain development and may ultimately inform diagnosis/treatment.


Assuntos
Encéfalo/diagnóstico por imagem , Dislexia/genética , Predisposição Genética para Doença , Transtornos do Desenvolvimento da Linguagem/diagnóstico por imagem , Pré-Escolar , Família , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Testes de Linguagem , Estudos Longitudinais , Masculino , Análise Multivariada , Tamanho do Órgão , Estudos Retrospectivos
9.
Cereb Cortex ; 26(3): 1138-1148, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25576531

RESUMO

Developmental dyslexia (DD) is highly heritable and previous studies observed reduced cortical volume, white matter integrity, and functional alterations in left posterior brain regions in individuals with DD. The primary sulcal pattern has been hypothesized to relate to optimal organization and connections of cortical functional areas. It is determined during prenatal development and may reflect early, genetically influenced, brain development. We characterize the sulcal pattern using graph-based pattern analysis and investigate whether sulcal patterns in parieto-temporal and occipito-temporal regions are atypical in elementary school-age children with DD and pre-readers/beginning readers (preschoolers/kindergarteners) with a familial risk (elementary school-age children: n [males/females], age range = 17/11, 84-155 months; preschoolers/kindergarteners: 16/15, 59-84 months). The pattern of sulcal basin area in left parieto-temporal and occipito-temporal regions was significantly atypical (more sulcal basins of smaller size) in children with DD and further correlated with reduced reading performance on single- and nonword reading measures. A significantly atypical sulcal area pattern was also confirmed in younger preschoolers/kindergarteners with a familial risk of DD. Our results provide further support for atypical early brain development in DD and suggest that DD may originate from altered organization or connections of cortical areas in the left posterior regions.


Assuntos
Córtex Cerebral/patologia , Dislexia/patologia , Córtex Cerebral/crescimento & desenvolvimento , Criança , Pré-Escolar , Família , Feminino , Predisposição Genética para Doença , Humanos , Imageamento por Ressonância Magnética , Masculino
10.
PLoS One ; 10(9): e0136553, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26339798

RESUMO

Recent neuroimaging work has suggested that aggressive behaviour (AB) is associated with structural and functional brain abnormalities in processes subserving emotion processing and regulation. However, most neuroimaging studies on AB to date only contain relatively small sample sizes. To objectively investigate the consistency of previous structural and functional research in adolescent AB, we performed a systematic literature review and two coordinate-based activation likelihood estimation meta-analyses on eight VBM and nine functional neuroimaging studies in a total of 783 participants (408 [224AB/184 controls] and 375 [215 AB/160 controls] for structural and functional analysis respectively). We found 19 structural and eight functional foci of significant alterations in adolescents with AB, mainly located within the emotion processing and regulation network (including orbitofrontal, dorsomedial prefrontal and limbic cortex). A subsequent conjunction analysis revealed that functional and structural alterations co-localize in right dorsomedial prefrontal cortex and left insula. Our results are in line with meta-analytic work as well as structural, functional and connectivity findings to date, all of which make a strong point for the involvement of a network of brain areas responsible for emotion processing and regulation, which is disrupted in AB. Increased knowledge about the behavioural and neuronal underpinnings of AB is crucial for the development of novel and implementation of existing treatment strategies. Longitudinal research studies will have to show whether the observed alterations are a result or primary cause of the phenotypic characteristics in AB.


Assuntos
Agressão/psicologia , Mapeamento Encefálico/estatística & dados numéricos , Lobo Límbico/fisiopatologia , Vias Neurais/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Adolescente , Estudos de Casos e Controles , Feminino , Neuroimagem Funcional , Humanos , Funções Verossimilhança , Lobo Límbico/patologia , Masculino , Vias Neurais/patologia , Córtex Pré-Frontal/patologia
11.
Neuroimage Clin ; 8: 230-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26110110

RESUMO

BACKGROUND: Individuals with at-risk mental state for psychosis (ARMS) often suffer from depressive and anxiety symptoms, which are clinically similar to the negative symptomatology described for psychosis. Thus, many ARMS individuals are already being treated with antidepressant medication. OBJECTIVES: To investigate clinical and structural differences between psychosis high-risk individuals with or without antidepressants. METHODS: We compared ARMS individuals currently receiving antidepressants (ARMS-AD; n = 18), ARMS individuals not receiving antidepressants (ARMS-nonAD; n = 31) and healthy subjects (HC; n = 24), in terms of brain structure abnormalities, using voxel-based morphometry. We also performed region of interest analysis for the hippocampus, anterior cingulate cortex, amygdala and precuneus. RESULTS: The ARMS-AD had higher 'depression' and lower 'motor hyperactivity' scores than the ARMS-nonAD. Compared to HC, there was significantly less GMV in the middle frontal gyrus in the whole ARMS cohort and in the superior frontal gyrus in the ARMS-AD subgroup. Compared to ARMS-nonAD, the ARMS-AD group showed more gray matter volume (GMV) in the left superior parietal lobe, but less GMV in the left hippocampus and the right precuneus. We found a significant negative correlation between attenuated negative symptoms and hippocampal volume in the whole ARMS cohort. CONCLUSION: Reduced GMV in the hippocampus and precuneus is associated with short-term antidepressant medication and more severe depressive symptoms. Hippocampal volume is further negatively correlated with attenuated negative psychotic symptoms. Longitudinal studies are needed to distinguish whether hippocampal volume deficits in the ARMS are related to attenuated negative psychotic symptoms or to antidepressant action.


Assuntos
Antidepressivos/uso terapêutico , Depressão/fisiopatologia , Hipocampo/patologia , Lobo Parietal/patologia , Transtornos Psicóticos/fisiopatologia , Adulto , Depressão/tratamento farmacológico , Feminino , Humanos , Masculino , Transtornos Psicóticos/tratamento farmacológico , Adulto Jovem
12.
PLoS One ; 9(12): e115549, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25532132

RESUMO

Studies in sleeping newborns and infants propose that the superior temporal sulcus is involved in speech processing soon after birth. Speech processing also implicitly requires the analysis of the human voice, which conveys both linguistic and extra-linguistic information. However, due to technical and practical challenges when neuroimaging young children, evidence of neural correlates of speech and/or voice processing in toddlers and young children remains scarce. In the current study, we used functional magnetic resonance imaging (fMRI) in 20 typically developing preschool children (average age  = 5.8 y; range 5.2-6.8 y) to investigate brain activation during judgments about vocal identity versus the initial speech sound of spoken object words. FMRI results reveal common brain regions responsible for voice-specific and speech-sound specific processing of spoken object words including bilateral primary and secondary language areas of the brain. Contrasting voice-specific with speech-sound specific processing predominantly activates the anterior part of the right-hemispheric superior temporal sulcus. Furthermore, the right STS is functionally correlated with left-hemispheric temporal and right-hemispheric prefrontal regions. This finding underlines the importance of the right superior temporal sulcus as a temporal voice area and indicates that this brain region is specialized, and functions similarly to adults by the age of five. We thus extend previous knowledge of voice-specific regions and their functional connections to the young brain which may further our understanding of the neuronal mechanism of speech-specific processing in children with developmental disorders, such as autism or specific language impairments.


Assuntos
Encéfalo/fisiologia , Fonética , Percepção da Fala/fisiologia , Voz/fisiologia , Adulto , Mapeamento Encefálico , Criança , Pré-Escolar , Feminino , Seguimentos , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino
13.
Proc Natl Acad Sci U S A ; 109(6): 2156-61, 2012 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-22308323

RESUMO

Individuals with developmental dyslexia (DD) show a disruption in posterior left-hemispheric neural networks during phonological processing. Additionally, compensatory mechanisms in children and adults with DD have been located within frontal brain areas. However, it remains unclear when and how differences in posterior left-hemispheric networks manifest and whether compensatory mechanisms have already started to develop in the prereading brain. Here we investigate functional networks during phonological processing in 36 prereading children with a familial risk for DD (n = 18, average age = 66.50 mo) compared with age and IQ-matched controls (n = 18; average age = 65.61 mo). Functional neuroimaging results reveal reduced activation in prereading children with a family-history of DD (FHD(+)), compared with those without (FHD(-)), in bilateral occipitotemporal and left temporoparietal brain regions. This finding corresponds to previously identified hypoactivations in left hemispheric posterior brain regions for school-aged children and adults with a diagnosis of DD. Furthermore, left occipitotemporal and temporoparietal brain activity correlates positively with prereading skills in both groups. Our results suggest that differences in neural correlates of phonological processing in individuals with DD are not a result of reading failure, but are present before literacy acquisition starts. Additionally, no hyperactivation in frontal brain regions was observed, suggesting that compensatory mechanisms for reading failure are not yet present. Future longitudinal studies are needed to determine whether the identified differences may serve as neural premarkers for the early identification of children at risk for DD.


Assuntos
Cérebro/fisiologia , Dislexia/fisiopatologia , Leitura , Adulto , Comportamento/fisiologia , Mapeamento Encefálico , Criança , Demografia , Humanos , Imageamento por Ressonância Magnética
14.
Neuroimage ; 57(3): 742-9, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20884362

RESUMO

Functional magnetic resonance imaging studies have reported reduced activation in parietotemporal and occipitotemporal areas in adults and children with developmental dyslexia compared to controls during reading and reading related tasks. These patterns of regionally reduced activation have been linked to behavioral impairments of reading-related processes (e.g., phonological skills and rapid automatized naming). The observed functional and behavioral differences in individuals with developmental dyslexia have been complemented by reports of reduced gray matter in left parietotemporal, occipitotemporal areas, fusiform and lingual gyrus and the cerebellum. An important question for education is whether these neural differences are present before reading is taught. Developmental dyslexia can only be diagnosed after formal reading education starts. However, here we investigate whether the previously detected gray matter alterations in adults and children with developmental dyslexia can already be observed in a small group of pre-reading children with a family-history of developmental dyslexia compared to age and IQ-matched children without a family-history (N = 20/mean age: 5:9 years; age range 5:1-6:5 years). Voxel-based morphometry revealed significantly reduced gray matter volume indices for pre-reading children with, compared to children without, a family-history of developmental dyslexia in left occipitotemporal, bilateral parietotemporal regions, left fusiform gyrus and right lingual gyrus. Gray matter volume indices in left hemispheric occipitotemporal and parietotemporal regions of interest also correlated positively with rapid automatized naming. No differences between the two groups were observed in frontal and cerebellar regions. This discovery in a small group of children suggests that previously described functional and structural alterations in developmental dyslexia may not be due to experience-dependent brain changes but may be present at birth or develop in early childhood prior to reading onset. Further studies using larger sample sizes and longitudinal analyses are needed in order to determine whether the identified structural alterations may be utilized as structural markers for the early identification of children at risk, which may prevent the negative clinical, social and psychological outcome of developmental dyslexia.


Assuntos
Encéfalo/patologia , Dislexia/patologia , Pré-Escolar , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Leitura
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