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1.
medRxiv ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38826357

RESUMO

Our genetic makeup, together with environmental and social influences, shape our brain's development. Yet, the imaging genetics field has struggled to integrate all these modalities to investigate the interplay between genetic blueprint, environment, human health, daily living skills and outcomes. Hence, we interrogated the Adolescent Brain Cognitive Development (ABCD) cohort to outline the effects of rare high-effect genetic variants on brain architecture and corresponding implications on cognitive, behavioral, psychosocial, and socioeconomic traits. Specifically, we designed a holistic pattern-learning algorithm that quantitatively dissects the impacts of copy number variations (CNVs) on brain structure and 962 behavioral variables spanning 20 categories in 7,657 adolescents. Our results reveal associations between genetic alterations, higher-order brain networks, and specific parameters of the family well-being (increased parental and child stress, anxiety and depression) or neighborhood dynamics (decreased safety); effects extending beyond the impairment of cognitive ability or language capacity, dominantly reported in the CNV literature. Our investigation thus spotlights a far-reaching interplay between genetic variation and subjective life quality in adolescents and their families.

2.
Dev Cogn Neurosci ; 65: 101340, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38218015

RESUMO

Previous brain imaging studies have identified three brain regions that selectively respond to visual scenes, the parahippocampal place area (PPA), the occipital place area (OPA), and the retrosplenial cortex (RSC). There is growing evidence that these visual scene-sensitive regions process different types of scene information and may have different developmental timelines in supporting scene perception. How these scene-sensitive regions support memory functions during child development is largely unknown. We investigated PPA, OPA and RSC activations associated with episodic memory formation in childhood (5-7 years of age) and young adulthood, using a subsequent scene memory paradigm and a functional localizer for scenes. PPA, OPA, and RSC subsequent memory activation and functional connectivity differed between children and adults. Subsequent memory effects were found in activations of all three scene regions in adults. In children, however, robust subsequent memory effects were only found in the PPA. Functional connectivity during successful encoding was significant among the three regions in adults, but not in children. PPA subsequently memory activations and PPA-RSC subsequent memory functional connectivity correlated with accuracy in adults, but not children. These age-related differences add new evidence linking protracted development of the scene-sensitive regions to the protracted development of episodic memory.


Assuntos
Mapeamento Encefálico , Memória Episódica , Adulto , Criança , Humanos , Adulto Jovem , Mapeamento Encefálico/métodos , Desenvolvimento Infantil , Imageamento por Ressonância Magnética/métodos , Estimulação Luminosa , Reconhecimento Visual de Modelos/fisiologia
3.
Cereb Cortex ; 33(10): 6028-6037, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-36520501

RESUMO

Recollection of past events has been associated with the core recollection network comprising the posterior medial temporal lobe and parietal regions, as well as the medial prefrontal cortex (mPFC). The development of the brain basis for recollection is understudied. In a sample of adults (n = 22; 18-25 years) and children (n = 23; 9-13 years), the present study aimed to address this knowledge gap using a cued recall paradigm, known to elicit recollection experience. Successful recall was associated with activations in regions of the core recollection network and frontoparietal network. Adults exhibited greater successful recall activations compared with children in the precuneus and right angular gyrus. In contrast, similar levels of successful recall activations were observed in both age groups in the mPFC. Group differences were also seen in the hippocampus and lateral frontal regions. These findings suggest that the engagement of the mPFC in episodic retrieval may be relatively early maturing, whereas the contribution to episodic retrieval of more posterior regions such as the precuneus and angular gyrus undergoes more protracted maturation.


Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Adulto , Criança , Humanos , Rememoração Mental , Encéfalo/diagnóstico por imagem , Lobo Parietal
4.
PLoS One ; 17(7): e0271143, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35788573

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0248044.].

5.
Child Dev ; 93(6): 1848-1859, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35841288

RESUMO

Information learned in relation to oneself is typically better remembered, termed the self-reference effect (SRE). This study aimed to elucidate the developmental trajectory of the SRE in recollection and source memory from mid-childhood to young adulthood. In 2018-2019 in Baltimore, Maryland, 136 seven- to thirty-year-olds (77 female; approximately 80% White, 15% Asian American, 5% Black) viewed objects on one of two backgrounds and answered a self-referential or semantic question for each. A recognition test probed memory for objects and source details (inherent: question type; peripheral: background image). SRE increased with age for detailed recollection (r = .189), but not familiarity, and extended to inherent source memory. This suggests that self-referencing promotes richer memory in children and develops into young adulthood.


Assuntos
Rememoração Mental , Autoimagem , Feminino , Humanos , Adulto Jovem , Adulto , Criança , Reconhecimento Psicológico , Semântica
6.
PLoS One ; 16(4): e0248044, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33857141

RESUMO

Information that is encoded in relation to the self has been shown to be better remembered, yet reports have disagreed on whether the memory benefit from self-referential encoding extends to source memory (the context in which information was learned). In this study, we investigated the self-referential effect on source memory in recollection and familiarity-based memory. Using a Remember/Know paradigm, we compared source memory accuracy under self-referential encoding and semantic encoding. Two types of source information were included, a "peripheral" source which was not inherent to the encoding activity, and a source information about the encoding context. We observed the facilitation in item memory from self-referential encoding compared to semantic encoding in recollection but not in familiarity-based memory. The self-referential benefit to source accuracy was observed in recollection memory, with source memory for the encoding context being stronger in the self-referential condition. No significant self-referential effect was observed with regards to peripheral source information (information not required for the participant to focus on), suggesting not all source information benefit from self-referential encoding. Self-referential encoding also resulted in a higher ratio of "Remember/Know" responses rate than semantically encoded items, denoting stronger recollection. These results suggest self-referential encoding creates a richer, more detailed memory trace which can be recollected later on.


Assuntos
Memória/fisiologia , Rememoração Mental/fisiologia , Adulto , Emoções/fisiologia , Feminino , Humanos , Masculino , Reconhecimento Psicológico/fisiologia , Autoimagem
7.
Neuroimage Clin ; 27: 102266, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32408198

RESUMO

Emotional dysregulation symptoms in youth frequently predispose individuals to increased risk for mood disorders and other mental health difficulties. These symptoms are also known as a behavioral risk marker in predicting pediatric mood disorders. The underlying neural mechanism of emotional dysregulation, however, remains unclear. This study used the diffusion tensor imaging (DTI) technique to identify anatomically specific variation in white-matter microstructure that is associated with pediatric emotional dysregulation severity. Thirty-two children (mean age 9.53 years) with varying levels of emotional dysregulation symptoms were recruited by the Massachusetts General Hospital and underwent the DTI scans at Massachusetts Institute of Technology. Emotional dysregulation severity was measured by the empirically-derived Child Behavior Checklist Emotional Dysregulation Profile that includes the Attention, Aggression, and Anxiety/Depression subscales. Whole-brain voxel-wise regression tests revealed significantly increased radial diffusivity (RD) and decreased fractional anisotropy (FA) in the cingulum-callosal regions linked to greater emotional dysregulation in the children. The results suggest that microstructural differences in cingulum-callosal white-matter pathways may manifest as a neurodevelopmental vulnerability for pediatric mood disorders as implicated in the clinical phenotype of pediatric emotional dysregulation. These findings may offer clinically and biologically relevant neural targets for early identification and prevention efforts for pediatric mood disorders.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Imagem de Tensor de Difusão , Emoções/fisiologia , Adolescente , Anisotropia , Criança , Corpo Caloso/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Substância Branca/diagnóstico por imagem
8.
Brain Lang ; 196: 104645, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31284145

RESUMO

Given the ubiquity of noisy environments and increasing globalization, the necessity to perceive speech in noise in a non-native language is common and necessary for successful communication. In the current investigation, bilingual individuals who learned their non-native language at different ages underwent magnetic resonance imaging while listening to sentences in both of their languages, in quiet and in noise. Sentence context was varied such that the final word could be of high or low predictability. Results show that early non-native language learning is associated with superior ability to benefit from contextual information behaviourally, and a pattern of neural recruitment in the left inferior frontal gyrus that suggests easier processing when perceiving non-native speech in noise. These findings have implications for our understanding of speech processing in non-optimal listening conditions and shed light on how individuals navigate every day complex communicative environments, in a native and non-native language.


Assuntos
Aprendizagem , Multilinguismo , Ruído , Percepção da Fala , Adulto , Compreensão , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
9.
Neuroradiology ; 61(9): 1047-1054, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31222381

RESUMO

PURPOSE: Developmental in nature, brain arteriovenous malformations (AVM) have the potential to affect whole brain organization. Here we investigated the impact of AVM on functional and structural brain organization using resting-state functional MRI (rsfMRI) and cortical thickness measures. METHODS: We investigated brain functional organization and structure using rsfMRI in conjunction with cortical thickness analyses in 23 patients with cerebral arteriovenous malformations (AVMs) and 20 healthy control subjects. RESULTS: Healthy controls showed the expected anti-correlation between activity in the default mode network (DMN) and frontal areas that are part of the attentional control network. By contrast, patients demonstrated a disruption of this anti-correlation. Disruptions to this anti-correlation were even observed in a subgroup of patients with lesions remote from the main nodes of the DMN and were unrelated to differences in perfusion. Functional connectivity differences were accompanied by reduced cortical thickness in frontal attentional areas in patients compared to the controls. CONCLUSIONS: These results contribute to the discussion that AVMs affect whole brain networks and not simply the area surrounding the lesion.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adolescente , Adulto , Estudos de Casos e Controles , Córtex Cerebral/fisiopatologia , Circulação Cerebrovascular , Feminino , Humanos , Malformações Arteriovenosas Intracranianas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Descanso , Adulto Jovem
10.
Brain Connect ; 9(5): 388-398, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30848160

RESUMO

Children with familial risk for major depressive disorder (MDD) have elevated risk for developing depression as adolescents. Here, we investigated longitudinally whether resting-state functional connectivity (RSFC) could predict the onset of MDD. In this pilot study, we followed a group of never-depressed children with familial risk for MDD and a group of age-matched controls without familial risk who had undergone an MRI study at 8-14 years of age. Participants were reassessed 3-4 years later with diagnostic interviews. We first investigated group differences in RSFC from regions in the emotion regulation, cognitive control, and default mode networks in the children who later developed MDD (converted), the children who did not develop MDD (nonconverted), and the control group. We then built a prediction model based on baseline RSFC that was independent of the group differences to classify the individuals who later developed MDD. Compared with the nonconverted group, the converted group exhibited hypoconnectivity between subgenual anterior cingulate cortex (sgACC) and inferior parietal lobule (IPL) and between left and right dorsolateral prefrontal cortices. The nonconverted group exhibited higher sgACC-IPL connectivity than did both the converted and control groups, suggesting a possible resilience factor to MDD. Classification between converted and nonconverted individuals based on baseline RSFC yielded high predictive accuracy with high sensitivity and specificity that was superior to classification based on baseline clinical rating scales. Intrinsic brain connectivity measured in healthy children with familial risk for depression has the potential to predict MDD onset, and it can be a useful neuromarker in early identification of children for preventive treatment.


Assuntos
Mapeamento Encefálico/métodos , Transtorno Depressivo Maior/diagnóstico por imagem , Vias Neurais/fisiopatologia , Adolescente , Encéfalo/fisiopatologia , Criança , Simulação por Computador , Transtorno Depressivo Maior/metabolismo , Feminino , Giro do Cíngulo/fisiopatologia , Humanos , Sistema Límbico/fisiopatologia , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Masculino , Vias Neurais/metabolismo , Lobo Parietal/fisiopatologia , Projetos Piloto , Córtex Pré-Frontal/fisiopatologia , Prognóstico , Descanso
11.
Psychiatry Res Neuroimaging ; 285: 31-39, 2019 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-30716688

RESUMO

Although research highlights neural correlates of Major Depressive Disorder (MDD), it is unclear whether these correlates reflect the state of depression or a pre-existing risk factor. The current study examined whether baseline differences in brain activations, resting-state connectivity, and brain structural differences between non-symptomatic children at high- and low-risk for MDD based on familial depression prospectively predict the onset of a depressive episode or increases in depressive symptomatology. We re-assessed 44 participants (28 high-risk; 16 low-risk) who had undergone neuroimaging in a previous study 3-4 years earlier (Mean age at follow-up = 14.3 years, SD = 1.9 years; 45% females; 70% Caucasian). We investigated whether baseline brain imaging data (including an emotional face match task fMRI, resting-state fMRI and structural MRI) that differentiated the risk groups also predicted the onset of depression. Resting-state functional connectivity abnormalities in the default mode and cognitive control network that differentiated high-risk from low-risk youth at baseline predicted the onset of MDD during adolescence, after taking risk status into account. Increased functional activation to both happy and fearful faces was associated with greater decreases in self-reported depression symptoms at follow-up. This preliminary evidence could be used to identify youth at-risk for depression and inform early intervention strategies.


Assuntos
Encéfalo/diagnóstico por imagem , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/psicologia , Imageamento por Ressonância Magnética/métodos , Autorrelato , Adolescente , Encéfalo/fisiopatologia , Criança , Transtorno Depressivo Maior/fisiopatologia , Emoções/fisiologia , Feminino , Seguimentos , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
12.
Neuropsychologia ; 117: 123-134, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29727624

RESUMO

We investigated the independent contributions of second language (L2) age of acquisition (AoA) and social diversity of language use on intrinsic brain organization using seed-based resting-state functional connectivity among highly proficient French-English bilinguals. There were two key findings. First, earlier L2 AoA related to greater interhemispheric functional connectivity between homologous frontal brain regions, and to decreased reliance on proactive executive control in an AX-Continuous Performance Task completed outside the scanner. Second, greater diversity in social language use in daily life related to greater connectivity between the anterior cingulate cortex and the putamen bilaterally, and to increased reliance on proactive control in the same task. These findings suggest that early vs. late L2 AoA links to a specialized neural framework for processing two languages that may engage a specific type of executive control (e.g., reactive control). In contrast, higher vs. lower degrees of diversity in social language use link to a broadly distributed set of brain networks implicated in proactive control and context monitoring.


Assuntos
Encéfalo/fisiologia , Desenvolvimento da Linguagem , Multilinguismo , Vias Neurais/fisiologia , Descanso , Fatores Sociológicos , Adolescente , Adulto , Fatores Etários , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Função Executiva/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Adulto Jovem
13.
Brain Cogn ; 117: 49-56, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28648285

RESUMO

This study explores the effect of individual differences in the age of acquisition of a second language using resting-state functional magnetic resonance imaging (rs-fMRI) to examine functional connectivity and its relation with cognitive control within bilinguals. We compared simultaneous bilinguals, who learned two languages from birth, to sequential bilinguals, who learned a second language following mastery of their first language. Results show an effect of language experience on the strength of anticorrelation between the default mode network and the task-positive attention network and on cognitive control, with simultaneous bilinguals demonstrating stronger anticorrelations between the two networks, as well as superior cognitive control compared to sequential bilinguals. These findings demonstrate that the timing of language learning may have an impact on cognitive control, with the simultaneous learning of two languages being associated with more optimal brain connectivity for cognitive control compared to sequential language learning.


Assuntos
Encéfalo/fisiologia , Cognição/fisiologia , Função Executiva/fisiologia , Idioma , Multilinguismo , Rede Nervosa/fisiologia , Adulto , Atenção/fisiologia , Mapeamento Encefálico/métodos , Feminino , Humanos , Individualidade , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto Jovem
14.
Neuropsychologia ; 98: 169-176, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27725166

RESUMO

Research to date suggests that second language acquisition results in functional and structural changes in the bilingual brain, however, in what way and how quickly these changes occur remains unclear. To address these questions, we studied fourteen English-speaking monolingual adults enrolled in a 12-week intensive French language-training program in Montreal. Using functional MRI, we investigated the neural changes associated with new language acquisition. The participants were scanned before the start of the immersion program and at the end of the 12 weeks. The fMRI scan aimed to investigate the brain regions recruited in a sentence reading task both in English, their first language (L1), and in French, their second language (L2). For the L1, fMRI patterns did not change from Time 1 to Time 2, while for the L2, the brain response changed between Time 1 and Time 2 in language-related areas. Of note, for the L2, there was higher activation at Time 2 compared to Time 1 in the left inferior parietal lobule (IPL) including the supramarginal gyrus. At Time 2 this higher activation in the IPL correlated with faster L2 reading speed. Moreover, higher activation in the left IPL at Time 1 predicted improvement in L2 reading speed from Time 1 to Time 2. Our results suggest that learning-induced plasticity occurred as early as 12 weeks into immersive second-language training, and that the IPL appears to play a special role in language learning.


Assuntos
Mapeamento Encefálico , Lateralidade Funcional/fisiologia , Imageamento por Ressonância Magnética , Multilinguismo , Lobo Parietal/diagnóstico por imagem , Aprendizagem Verbal/fisiologia , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Oxigênio/sangue , Lobo Parietal/fisiologia , Análise de Regressão , Fatores de Tempo , Adulto Jovem
15.
Cereb Cortex ; 27(9): 4478-4491, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27578495

RESUMO

Depression is among the most common neuropsychiatric disorders. It remains unclear whether brain abnormalities associated with depression reflect the pathological state of the disease or neurobiological traits predisposing individuals to depression. Parental history of depression is a risk factor that more than triples the risk of depression. We compared white matter (WM) microstructure cross-sectionally in 40 children ages 8-14 with versus without parental history of depression (At-Risk vs. Control). There were significant differences in age-related changes of fractional anisotropy (FA) between the groups, localized in the anterior fronto-limbic WM pathways, including the anterior cingulum and the genu of the corpus callosum. Control children exhibited typical increasing FA with age, whereas At-Risk children exhibited atypical decreasing FA with age in these fronto-limbic regions. Furthermore, dorsal cingulate FA significantly correlated with depressive symptoms for At-Risk children. The results suggest maturational WM microstructure differences in mood-regulatory neurocircuitry that may contribute to neurodevelopmental risk for depression. The study provides new insights into neurodevelopmental susceptibility to depression and related disabilities that may promote early preventive intervention approaches.


Assuntos
Corpo Caloso/patologia , Transtorno Depressivo Maior/diagnóstico por imagem , Rede Nervosa/patologia , Substância Branca/patologia , Adolescente , Afeto/fisiologia , Anisotropia , Criança , Transtorno Depressivo Maior/metabolismo , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino
16.
Soc Cogn Affect Neurosci ; 12(1): 116-127, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27798254

RESUMO

Although a growing body of literature suggests that cognitive control processes are involved in deception, much about the neural correlates of lying remains unknown. In this study, we tested whether brain activation associated with deception, as measured by functional magnetic resonance imaging (fMRI), can be detected either in preparation for or during the execution of a lie, and whether they depend on the content of the lie. We scanned participants while they lied or told the truth about either their personal experiences (episodic memories) or personal beliefs. Regions in the frontal and parietal cortex showed higher activation when participants lied compared with when they were telling the truth, regardless of whether they were asked about their past experiences or opinions. In contrast, lie-related activation in the right temporal pole, precuneus and the right amygdala differed by the content of the lie. Preparing to lie activated parietal and frontal brain regions that were distinct from those activated while participants executed lies. Our findings concur with previous reports on the involvement of frontal and parietal regions in deception, but specify brain regions involved in the preparation vs execution of deception, and those involved in deceiving about experiences vs opinions.


Assuntos
Encéfalo/fisiologia , Enganação , Adolescente , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Face , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto Jovem
17.
Biol Psychiatry ; 80(11): 849-858, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-26826874

RESUMO

BACKGROUND: Neuroimaging studies of patients with major depression have revealed abnormal intrinsic functional connectivity measured during the resting state in multiple distributed networks. However, it is unclear whether these findings reflect the state of major depression or reflect trait neurobiological underpinnings of risk for major depression. METHODS: We compared resting-state functional connectivity, measured with functional magnetic resonance imaging, between unaffected children of parents who had documented histories of major depression (at-risk, n = 27; 8-14 years of age) and age-matched children of parents with no lifetime history of depression (control subjects, n = 16). RESULTS: At-risk children exhibited hyperconnectivity between the default mode network and subgenual anterior cingulate cortex/orbital frontal cortex, and the magnitude of connectivity positively correlated with individual symptom scores. At-risk children also exhibited 1) hypoconnectivity within the cognitive control network, which also lacked the typical anticorrelation with the default mode network; 2) hypoconnectivity between left dorsolateral prefrontal cortex and subgenual anterior cingulate cortex; and 3) hyperconnectivity between the right amygdala and right inferior frontal gyrus, a key region for top-down modulation of emotion. Classification between at-risk children and control subjects based on resting-state connectivity yielded high accuracy with high sensitivity and specificity that was superior to clinical rating scales. CONCLUSIONS: Children at familial risk for depression exhibited atypical functional connectivity in the default mode, cognitive control, and affective networks. Such task-independent functional brain measures of risk for depression in children could be used to promote early intervention to reduce the likelihood of developing depression.


Assuntos
Córtex Cerebral/fisiopatologia , Filho de Pais com Deficiência , Conectoma , Transtorno Depressivo Maior/fisiopatologia , Rede Nervosa/fisiopatologia , Adolescente , Criança , Feminino , Predisposição Genética para Doença , Humanos , Imageamento por Ressonância Magnética , Masculino , Risco
18.
J Neurosci ; 36(3): 755-61, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26791206

RESUMO

There is considerable variability in an individual's ability to acquire a second language (L2) during adulthood. Using resting-state fMRI data acquired before training in English speakers who underwent a 12 week intensive French immersion training course, we investigated whether individual differences in intrinsic resting-state functional connectivity relate to a person's ability to acquire an L2. We focused on two key aspects of language processing--lexical retrieval in spontaneous speech and reading speed--and computed whole-brain functional connectivity from two regions of interest in the language network, namely the left anterior insula/frontal operculum (AI/FO) and the visual word form area (VWFA). Connectivity between the left AI/FO and left posterior superior temporal gyrus (STG) and between the left AI/FO and dorsal anterior cingulate cortex correlated positively with improvement in L2 lexical retrieval in spontaneous speech. Connectivity between the VWFA and left mid-STG correlated positively with improvement in L2 reading speed. These findings are consistent with the different language functions subserved by subcomponents of the language network and suggest that the human capacity to learn an L2 can be predicted by an individual's intrinsic functional connectivity within the language network. Significance statement: There is considerable variability in second-language learning abilities during adulthood. We investigated whether individual differences in intrinsic functional connectivity in the adult brain relate to success in second-language learning, using resting-state functional magnetic resonance imaging in English speakers who underwent a 12 week intensive French immersion training course. We found that pretraining functional connectivity within two different language subnetworks correlated strongly with learning outcome in two different language skills: lexical retrieval in spontaneous speech and reading speed. Our results suggest that the human capacity to learn a second language can be predicted by an individual's intrinsic functional connectivity within the language network.


Assuntos
Encéfalo/fisiologia , Compreensão/fisiologia , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética/métodos , Multilinguismo , Rede Nervosa/fisiologia , Adulto , Fatores Etários , Mapeamento Encefálico/métodos , Feminino , Humanos , Masculino , Adulto Jovem
19.
Addict Biol ; 21(4): 972-81, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-25990865

RESUMO

Although nicotine addiction is characterized by both structural and functional abnormalities in brain networks involved in salience and cognitive control, few studies have integrated these data to understand how these abnormalities may support addiction. This study aimed to (1) evaluate gray matter density and functional connectivity of the anterior insula in cigarette smokers and never smokers and (2) characterize how differences in these measures were related to smoking behavior. We compared structural magnetic resonance imaging (MRI) (gray matter density via voxel-based morphometry) and seed-based functional connectivity MRI data in 16 minimally deprived smokers and 16 matched never smokers. Compared with controls, smokers had lower gray matter density in left anterior insula extending into inferior frontal and temporal cortex. Gray matter density in this region was inversely correlated with cigarettes smoked per day. Smokers exhibited negative functional connectivity (anti-correlation) between the anterior insula and regions involved in cognitive control (left lPFC) and semantic processing/emotion regulation (lateral temporal cortex), whereas controls exhibited positive connectivity between these regions. There were differences in the anterior insula, a central region in the brain's salience network, when comparing both volumetric and functional connectivity data between cigarette smokers and never smokers. Volumetric data, but not the functional connectivity data, were also associated with an aspect of smoking behavior (daily cigarettes smoked).


Assuntos
Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Fumantes/estatística & dados numéricos , Tabagismo/patologia , Tabagismo/fisiopatologia , Adolescente , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
Neuroimage Clin ; 8: 398-407, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26106565

RESUMO

Despite growing evidence for atypical amygdala function and structure in major depression, it remains uncertain as to whether these brain differences reflect the clinical state of depression or neurobiological traits that predispose individuals to major depression. We examined function and structure of the amygdala and associated areas in a group of unaffected children of depressed parents (at-risk group) and a group of children of parents without a history of major depression (control group). Compared to the control group, the at-risk group showed increased activation to fearful relative to neutral facial expressions in the amygdala and multiple cortical regions, and decreased activation to happy relative to neutral facial expressions in the anterior cingulate cortex and supramarginal gyrus. At-risk children also exhibited reduced amygdala volume. The extensive hyperactivation to negative facial expressions and hypoactivation to positive facial expressions in at-risk children are consistent with behavioral evidence that risk for major depression involves a bias to attend to negative information. These functional and structural brain differences between at-risk children and controls suggest that there are trait neurobiological underpinnings of risk for major depression.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Córtex Cerebral/fisiopatologia , Filho de Pais com Deficiência , Transtorno Depressivo Maior/fisiopatologia , Adolescente , Tonsila do Cerebelo/patologia , Córtex Cerebral/patologia , Criança , Transtorno Depressivo Maior/patologia , Expressão Facial , Feminino , Humanos , Masculino , Risco
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