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1.
Cereb Cortex ; 33(9): 5218-5227, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-36376964

RESUMO

Boys with fragile X syndrome (FXS), the leading known genetic cause of autism spectrum disorder (ASD), demonstrate significant impairments in social gaze and associated weaknesses in communication, social interaction, and other areas of adaptive functioning. Little is known, however, concerning the impact of behavioral treatments for these behaviors on functional brain connectivity in this population. As part of a larger study, boys with FXS (mean age 13.23 ± 2.31 years) and comparison boys with ASD (mean age 12.15 ± 2.76 years) received resting-state functional magnetic resonance imaging scans prior to and following social gaze training administered by a trained behavior therapist in our laboratory. Network-agnostic connectome-based predictive modeling of pretreatment resting-state functional connectivity data revealed a set of positive (FXS > ASD) and negative (FXS < ASD) edges that differentiated the groups significantly and consistently across all folds of cross-validation. Following administration of the brief training, the FXS and ASD groups demonstrated reorganization of connectivity differences. The divergence in the spatial pattern of reorganization response, based on functional connectivity differences pretreatment, suggests a unique pattern of response to treatment in the FXS and ASD groups. These results provide further support for implementing targeted behavioral treatments to ameliorate syndrome-specific behavioral features in FXS.


Assuntos
Transtorno do Espectro Autista , Síndrome do Cromossomo X Frágil , Masculino , Humanos , Criança , Adolescente , Encéfalo , Comunicação
2.
Mol Psychiatry ; 27(3): 1542-1551, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35087195

RESUMO

Mounting evidence supports the role of the Ras/mitogen-activated protein kinase (Ras/MAPK) pathway in neurodevelopmental disorders. Here, the authors used a genetics-first approach to examine how Ras/MAPK pathogenic variants affect the functional organization of the brain and cognitive phenotypes including weaknesses in attention and inhibition. Functional MRI was used to examine resting state functional connectivity (RSFC) in association with Ras/MAPK pathogenic variants in children with Noonan syndrome (NS). Participants (age 4-12 years) included 39 children with NS (mean age 8.44, SD = 2.20, 25 females) and 49 typically developing (TD) children (mean age 9.02, SD = 9.02, 33 females). Twenty-eight children in the NS group and 46 in the TD group had usable MRI data and were included in final analyses. The results indicated significant hyperconnectivity for the NS group within canonical visual, ventral attention, left frontoparietal and limbic networks (p < 0.05 FWE). Higher connectivity within canonical left frontoparietal and limbic networks positively correlated with cognitive function within the NS but not the TD group. Further, the NS group demonstrated significant group differences in seed-based striatal-frontal connectivity (Z > 2.6, p < 0.05 FWE). Hyperconnectivity within canonical brain networks may represent an intermediary phenotype between Ras/MAPK pathogenic variants and cognitive phenotypes, including weaknesses in attention and inhibition. Altered striatal-frontal connectivity corresponds with smaller striatal volume and altered white matter connectivity previously documented in children with NS. These results may indicate delayed maturation and compensatory mechanisms and they are important for understanding the pathophysiology underlying cognitive phenotypes in NS and in the broader population of children with neurodevelopmental disorders.


Assuntos
Sistema de Sinalização das MAP Quinases , Proteínas Quinases Ativadas por Mitógeno , Substância Branca , Proteínas ras , Atenção/fisiologia , Encéfalo/enzimologia , Encéfalo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Substância Branca/enzimologia , Substância Branca/patologia , Proteínas ras/metabolismo
3.
Mol Psychiatry ; 27(9): 3768-3776, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35595977

RESUMO

Girls with fragile X syndrome (FXS) often manifest significant symptoms of avoidance, anxiety, and arousal, particularly in the context of social interaction. However, little is currently known about the associations among neurobiological, biobehavioral such as eye gaze pattern, and social-cognitive dysfunction in real-world settings. In this study, we sought to characterize brain network properties and eye gaze patterns in girls with FXS during natural social interaction. Participants included 42 girls with FXS and 31 age- and verbal IQ-matched girls (control). Portable functional near-infrared spectroscopy (fNIRS) and an eye gaze tracker were used to investigate brain network alterations and eye gaze patterns associated with social-cognitive dysfunction in girls with FXS during a structured face-to-face conversation. Compared to controls, girls with FXS showed significantly increased inter-regional functional connectivity and greater excitability within the prefrontal cortex (PFC), frontal eye field (FEF) and superior temporal gyrus (STG) during the conversation. Girls with FXS showed significantly less eye contact with their conversational partner and more unregulated eye gaze behavior compared to the control group. We also demonstrated that a machine learning approach based on multimodal data, including brain network properties and eye gaze patterns, was predictive of multiple domains of social-cognitive behaviors in girls with FXS. Our findings expand current knowledge of neural mechanisms and eye gaze behaviors underlying naturalistic social interaction in girls with FXS. These results could be further evaluated and developed as intermediate phenotypic endpoints for treatment trial evaluation in girls with FXS.


Assuntos
Síndrome do Cromossomo X Frágil , Feminino , Humanos , Fixação Ocular , Interação Social , Encéfalo , Cognição
4.
Dev Med Child Neurol ; 65(11): 1520-1529, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37130201

RESUMO

AIM: We investigated neuropsychiatric outcomes in children with Noonan syndrome and addressed limitations in previous research with a focus on prepubertal children, comparison to typically developing children, comprehensive neuropsychiatric evaluation, and controlling for overall cognitive abilities. METHOD: Forty-five children with Noonan syndrome (mean = 8 years 6 months, SD = 2 years 2 months; 29 females) and 40 typically developing children (mean = 8 years 9 months, SD = 2 years; 22 females) were evaluated with objective, parent-report, and psychiatric interview measures. RESULTS: Children with Noonan syndrome demonstrated elevated symptoms across attention-deficit/hyperactivity disorder (ADHD) (attention, hyperactivity, and inhibition), autism spectrum disorder (ASD) (maintaining social relationships, behavioral rigidity, and sensory sensitivity), and oppositional defiant disorder (ODD) (aggression) symptom clusters relative to typically developing children (all p < 0.05). Group differences in nearly all parent-report measures were significant after accounting for variations in intellectual functioning, suggesting that increased neurodevelopmental symptoms are not simply driven by overall intelligence. Twenty out of 42 children with Noonan syndrome met criteria for ADHD, eight out of 42 for ODD, and 11 out of 43 demonstrated clinically significant symptoms seen in children with ASD. INTERPRETATION: Children with Noonan syndrome are at increased risk for a range of ADHD, ASD, and ODD associated symptoms. A dimensional approach reveals significant ASD symptoms in Noonan syndrome that do not emerge when using the currently accepted categorical diagnostic approach. WHAT THIS PAPER ADDS: Neuropsychiatric disorders occur in more than half of children with Noonan syndrome. Children with Noonan syndrome demonstrate highly variable neurodevelopmental symptom profiles. Children with Noonan syndrome display variable impairments in attention, hyperactivity, and inhibition. Specific social concerns include behavioral rigidity, transitions, and difficulties maintaining social relationships. Children with Noonan syndrome display variably elevated levels of aggression and emotional dysregulation.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Síndrome de Noonan , Feminino , Humanos , Criança , Síndrome de Noonan/complicações , Síndrome de Noonan/genética , Transtorno do Espectro Autista/psicologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Atenção , Fenótipo
5.
Cereb Cortex ; 32(11): 2310-2320, 2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34546362

RESUMO

Fragile X syndrome is a genetic condition associated with alterations in brain and subsequent cognitive development. However, due to a milder phenotype relative to males, females with fragile X syndrome are underrepresented in research studies. In the current study, we investigate neuroanatomical differences in young females (age range: 6.03-16.32 years) with fragile X syndrome (N = 46) as compared to age-, sex-, and verbal abilities-matched participants (comparison group; N = 35). Between-group analyses of whole-brain and regional brain volumes were assessed using voxel-based morphometry. Results demonstrate significantly larger total gray and white matter volumes in girls with fragile X syndrome compared to a matched comparison group (Ps < 0.001). In addition, the fragile X group showed significantly larger gray matter volume in a bilateral parieto-occipital cluster and a right parieto-occipital cluster (Ps < 0.001). Conversely, the fragile X group showed significantly smaller gray matter volume in the bilateral gyrus rectus (P < 0.03). Associations between these regional brain volumes and key socio-emotional variables provide insight into gene-brain-behavior relationships underlying the fragile X syndrome phenotype in females. These findings represent the first characterization of a neuroanatomical phenotype in a large sample of girls with fragile X syndrome and expand our knowledge about potential neurodevelopmental mechanisms underlying cognitive-behavioral outcomes in this condition.


Assuntos
Síndrome do Cromossomo X Frágil , Substância Branca , Encéfalo/diagnóstico por imagem , Feminino , Síndrome do Cromossomo X Frágil/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Substância Branca/diagnóstico por imagem
6.
Dev Psychopathol ; : 1-12, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37185087

RESUMO

Children with fragile X syndrome (FXS) often avoid eye contact, a behavior that is potentially related to hyperarousal. Prior studies, however, have focused on between-person associations rather than coupling of within-person changes in gaze behaviors and arousal. In addition, there is debate about whether prompts to maintain eye contact are beneficial for individuals with FXS. In a study of young females (ages 6-16), we used eye tracking to assess gaze behavior and pupil dilation during social interactions in a group with FXS (n = 32) and a developmentally similar comparison group (n = 23). Participants engaged in semi-structured conversations with a female examiner during blocks with and without verbal prompts to maintain eye contact. We identified a social-behavioral and psychophysiological profile that is specific to females with FXS; this group exhibited lower mean levels of eye contact, significantly increased mean pupil dilation during conversations that included prompts to maintain eye contact, and showed stronger positive coupling between eye contact and pupil dilation. Our findings strengthen support for the perspective that gaze aversion in FXS reflects negative reinforcement of social avoidance behavior. We also found that behavioral skills training may improve eye contact, but maintaining eye contact appears to be physiologically taxing for females with FXS.

7.
Cereb Cortex ; 31(12): 5570-5578, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34313731

RESUMO

Aging is the major risk factor for neurodegenerative diseases and affects neurite distributions throughout the brain, yet underlying neurobiological mechanisms remain unclear. Multi-shell diffusion-weighted imaging and neurite orientation dispersion and density imaging (NODDI) now provide in vivo biophysical measurements that explain these biological processes in the cortex and white matter. In this study, neurite distributions were evaluated in the cortex and white matter in healthy older adults and patients with amnestic mild cognitive impairment (aMCI) that provides fundamental contributions regarding healthy aging and neurodegeneration. Older age was associated with reduced neurite density and neurite orientation dispersion (ODI) in widespread cortical regions. In contrast, increased ODI was only observed in the right thalamus and hippocampus with age. For the first time, we also reported a widespread age-associated decrease in neurite density along major white matter tracts correlated with decreased cortical neurite density in the tract endpoints in healthy older adults. We further examined alterations in cortical and white matter neurite microstructures in aMCI patients and found significant neurite morphology deficits in memory networks correlated with memory performance. Our findings indicate that neurite parameters provide valuable information regarding cortical and white matter microstructure and complement myeloarchitectural information in healthy aging and aMCI.


Assuntos
Disfunção Cognitiva , Envelhecimento Saudável , Substância Branca , Idoso , Encéfalo , Disfunção Cognitiva/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Substância Cinzenta/diagnóstico por imagem , Humanos , Neuritos , Substância Branca/diagnóstico por imagem
8.
Environ Res ; 212(Pt C): 113461, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35550812

RESUMO

BACKGROUND: Epidemiological studies suggest that exposure to p,p'-dichloro-diphenyl-trichloroethane (p,p'-DDT) is associated with poorer cognitive function in children and adolescents, but the neural mechanisms underlying this association remain unclear. OBJECTIVE: We investigated associations of prenatal and childhood exposure to p,p'-DDT and its metabolite p,p'-dichloro-diphenyl-dichloroethylene (p,p'-DDE) with cortical activation in adolescents using functional near-infrared spectroscopy (fNIRS). METHODS: We administered fNIRS to 95 adolescents from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) aged 15-17 years. We assessed cortical activity in the frontal, temporal, and parietal brain regions while participants completed tasks of executive function, language comprehension, and social cognition. We measured serum p,p'-DDT and -DDE concentrations at age 9 years and then estimated exposure-outcome associations using linear regression models adjusted for sociodemographic characteristics. In secondary analyses, we back-extrapolated prenatal concentrations using prediction models and examined their association with cortical activation. RESULTS: Median (P25-P75) p,p'-DDT and -DDE concentrations in childhood were 1.4 (1-2.3) and 141.5 (75.0-281.3) ng/g lipid, respectively. We found that childhood exposure to p,p'-DDT and -DDE was associated with altered patterns of brain activation during tasks of cognition and executive functions. For example, we observed increased activity in the left frontal lobe during a language comprehension task (ß per 10 ng/g lipid increase of serum p,p'-DDE at age 9 years = 3.4; 95% CI: 0.0, 6.9 in the left inferior frontal lobe; and ß = 4.2; 95% CI: 0.9, 7.5 in the left superior frontal lobe). We found no sex differences in the associations of childhood p,p'-DDT and -DDE concentrations with neural activity. Associations between prenatal p,p'-DDT and p,p'-DDE concentrations and brain activity were similar to those observed for child p,p'-DDT and -DDE concentrations. CONCLUSIONS: Childhood p,p'-DDT and -DDE exposure may impact cortical brain activation, which could be an underlying mechanism for its previously reported associations with poorer cognitive function.


Assuntos
DDT , Diclorodifenil Dicloroetileno , Adolescente , Criança , Estudos de Coortes , DDT/toxicidade , Diclorodifenil Dicloroetileno/toxicidade , Feminino , Neuroimagem Funcional , Humanos , Lipídeos , Gravidez
9.
Proc Natl Acad Sci U S A ; 116(37): 18347-18356, 2019 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-31451641

RESUMO

We have reported consistent associations of prenatal organophosphate pesticide (OP) exposure with poorer cognitive function and behavior problems in our Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS), a birth cohort of Mexican American youth in California's agricultural Salinas Valley. However, there is little evidence on how OPs affect neural dynamics underlying associations. We used functional near-infrared spectroscopy (fNIRS) to measure cortical activation during tasks of executive function, attention, social cognition, and language comprehension in 95 adolescent CHAMACOS participants. We estimated associations of residential proximity to OP use during pregnancy with cortical activation in frontal, temporal, and parietal regions using multiple regression models, adjusting for sociodemographic characteristics. OP exposure was associated with altered brain activation during tasks of executive function. For example, with a 10-fold increase in total OP pesticide use within 1 km of maternal residence during pregnancy, there was a bilateral decrease in brain activation in the prefrontal cortex during a cognitive flexibility task (ß = -4.74; 95% CI: -8.18, -1.31 and ß = -4.40; 95% CI: -7.96, -0.84 for the left and right hemispheres, respectively). We also found that prenatal OP exposure was associated with sex differences in brain activation during a language comprehension task. This first functional neuroimaging study of prenatal OP exposure suggests that pesticides may impact cortical brain activation, which could underlie previously reported OP-related associations with cognitive and behavioral function. Use of fNIRS in environmental epidemiology offers a practical alternative to neuroimaging technologies and enhances our efforts to assess the impact of chemical exposures on neurodevelopment.


Assuntos
Neuroimagem Funcional , Inseticidas/efeitos adversos , Exposição Materna , Compostos Organofosforados/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Adolescente , Adulto , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , California , Exposição Ambiental , Feminino , Humanos , Testes de Linguagem , Masculino , Americanos Mexicanos , Pessoa de Meia-Idade , Transtornos do Neurodesenvolvimento/induzido quimicamente , Transtornos do Neurodesenvolvimento/epidemiologia , Praguicidas , Gravidez , Análise de Regressão , Caracteres Sexuais , Adulto Jovem
10.
Neuroimage ; 237: 118161, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34000394

RESUMO

Healthy and pathological aging influence brain microstructure via complex processes. Discerning these processes requires measurements that are sensitive to specific biological properties of brain tissue. We integrated a novel quantitative R1 measure with multi-shell diffusion weighted imaging to map age-associated changes in macromolecular tissue volume (MTV) along major white matter tracts in healthy older adults and patients with amnestic Mild Cognitive Impairment (aMCI). Reduced MTV in association tracts was associated with older age in healthy aging, was correlated with memory performance, and distinguished aMCI from controls. We also mapped changes in gray matter tissue properties using quantitative R1 measurements. We documented a widespread decrease in R1 with advancing age across the cortex and decreased R1 in aMCI compared with controls in regions implicated in episodic memory. Our data are the first to characterize MTV loss along major white matter tracts in aMCI and suggest that qMRI is a sensitive measure for detecting subtle degeneration of white and gray matter tissue that cannot be detected by conventional MRI and diffusion measures.


Assuntos
Envelhecimento , Córtex Cerebral/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Substância Cinzenta/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/patologia , Córtex Cerebral/patologia , Disfunção Cognitiva/patologia , Feminino , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória Episódica , Substância Branca/patologia
11.
Proc Natl Acad Sci U S A ; 114(40): 10767-10772, 2017 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-28923933

RESUMO

Fragile X syndrome (FXS), due to mutations of the FMR1 gene, is the most common known inherited cause of developmental disability. The cognitive, behavioral, and neurological phenotypes observed in affected individuals can vary considerably, making it difficult to predict outcomes and determine the need for interventions. We sought to examine early structural brain growth as a potential marker for identification of clinically meaningful subgroups. Participants included 42 very young boys with FXS who completed a T1-weighted anatomical MRI and cognitive/behavioral assessment at two longitudinal time points, with mean ages of 2.89 y and 4.91 y. Topological data analysis (TDA), an unsupervised approach to multivariate pattern analysis, was applied to the longitudinal anatomical data to identify coherent but heretofore unknown subgroups. TDA revealed two large subgroups within the study population based solely on longitudinal MRI data. Post hoc comparisons of cognition, adaptive functioning, and autism severity scores between these groups demonstrated that one group was consistently higher functioning on all measures at both time points, with pronounced and significant unidirectional differences (P < 0.05 for time point 1 and/or time point 2 for each measure). These results support the existence of two longitudinally defined, neuroanatomically distinct, and clinically relevant phenotypes among boys with FXS. If confirmed by additional analyses, such information may be used to predict outcomes and guide design of targeted therapies. Furthermore, TDA of longitudinal anatomical MRI data may represent a useful method for reliably and objectively defining subtypes within other neuropsychiatric disorders.


Assuntos
Encéfalo/patologia , Desenvolvimento Infantil , Cognição , Síndrome do Cromossomo X Frágil/patologia , Imageamento por Ressonância Magnética/métodos , Pré-Escolar , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Masculino , Testes Neuropsicológicos , Fenótipo
12.
Hum Brain Mapp ; 39(10): 3915-3927, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29885097

RESUMO

Improvements in vehicle safety require understanding of the neural systems that support the complex, dynamic task of real-world driving. We used functional near infrared spectroscopy (fNIRS) and pupilometry to quantify cortical and physiological responses during a realistic, simulated driving task in which vehicle dynamics were manipulated. Our results elucidate compensatory changes in driver behavior in response to changes in vehicle handling. We also describe associated neural and physiological responses under different levels of mental workload. The increased cortical activation we observed during the late phase of the experiment may indicate motor learning in prefrontal-parietal networks. Finally, relationships among cortical activation, steering control, and individual personality traits suggest that individual brain states and traits may be useful in predicting a driver's response to changes in vehicle dynamics. Results such as these will be useful for informing the design of automated safety systems that facilitate safe and supportive driver-car communication.


Assuntos
Condução de Veículo , Córtex Cerebral/fisiologia , Neuroimagem Funcional/métodos , Aprendizagem/fisiologia , Sistemas Homem-Máquina , Personalidade/fisiologia , Desempenho Psicomotor/fisiologia , Pupila/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Adolescente , Adulto , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Masculino , Adulto Jovem
13.
Dev Psychopathol ; 28(4pt2): 1457-1469, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26648140

RESUMO

Few studies have investigated developmental strengths and weaknesses within the cognitive profile of children and adolescents with fragile X syndrome (FXS), a single-gene cause of inherited intellectual impairment. With a prospective longitudinal design and using normalized raw scores (Z scores) to circumvent floor effects, we measured cognitive functioning of 184 children and adolescents with FXS (ages 6 to 16) using the Wechsler Scale of Intelligence for Children on one to three occasions for each participant. Participants with FXS received lower raw scores relative to the Wechsler Scale of Intelligence for Children normative sample across the developmental period. Verbal comprehension, perceptual organization, and processing speed Z scores were marked by a widening gap from the normative sample, while freedom from distractibility Z scores showed a narrowing gap. Key findings include a relative strength for verbal skills in comparison with visuospatial-constructive skills arising in adolescence and a discrepancy between working memory (weakness) and processing speed (strength) in childhood that diminishes in adolescence. Results suggest that the cognitive profile associated with FXS develops dynamically from childhood to adolescence. Findings are discussed within the context of aberrant brain morphology in childhood and maturation in adolescence. We argue that assessing disorder-specific cognitive developmental profiles will benefit future disorder-specific treatment research.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Desenvolvimento Infantil/fisiologia , Cognição/fisiologia , Síndrome do Cromossomo X Frágil/psicologia , Inteligência/fisiologia , Adolescente , Criança , Transtornos Cognitivos/psicologia , Compreensão/fisiologia , Feminino , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Testes Neuropsicológicos , Estudos Prospectivos , Escalas de Wechsler
14.
Neuroimage ; 120: 274-84, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26162553

RESUMO

Coordinated variations in brain morphology (e.g., cortical thickness) across individuals have been widely used to infer large-scale population brain networks. These structural correlation networks (SCNs) have been shown to reflect synchronized maturational changes in connected brain regions. Further, evidence suggests that SCNs, to some extent, reflect both anatomical and functional connectivity and hence provide a complementary measure of brain connectivity in addition to diffusion weighted networks and resting-state functional networks. Although widely used to study between-group differences in network properties, SCNs are inferred only at the group-level using brain morphology data from a set of participants, thereby not providing any knowledge regarding how the observed differences in SCNs are associated with individual behavioral, cognitive and disorder states. In the present study, we introduce two novel distance-based approaches to extract information regarding individual differences from the group-level SCNs. We applied the proposed approaches to a moderately large dataset (n=100) consisting of individuals with fragile X syndrome (FXS; n=50) and age-matched typically developing individuals (TD; n=50). We tested the stability of proposed approaches using permutation analysis. Lastly, to test the efficacy of our method, individual contributions extracted from the group-level SCNs were examined for associations with intelligence scores and genetic data. The extracted individual contributions were stable and were significantly related to both genetic and intelligence estimates, in both typically developing individuals and participants with FXS. We anticipate that the approaches developed in this work could be used as a putative biomarker for altered connectivity in individuals with neurodevelopmental disorders.


Assuntos
Encéfalo/patologia , Interpretação Estatística de Dados , Síndrome do Cromossomo X Frágil/patologia , Inteligência/fisiologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/patologia , Adolescente , Adulto , Encéfalo/anatomia & histologia , Criança , Feminino , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/fisiopatologia , Humanos , Individualidade , Masculino , Rede Nervosa/anatomia & histologia , Adulto Jovem
15.
Br J Psychiatry ; 207(2): 143-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25792692

RESUMO

BACKGROUND: Fragile-X syndrome (FXS) is a neurodevelopmental disorder associated with intellectual disability and neurobiological abnormalities including white matter microstructural differences. White matter differences have been found relative to neurotypical individuals. AIMS: To examine whether FXS white matter differences are related specifically to FXS or more generally to the presence of intellectual disability. METHOD: We used voxel-based and tract-based analytic approaches to compare individuals with FXS (n = 40) with gender- and IQ-matched controls (n = 30). RESULTS: Individuals with FXS had increased fractional anisotropy and decreased radial diffusivity values compared with IQ-matched controls in the inferior longitudinal, inferior fronto-occipital and uncinate fasciculi. CONCLUSIONS: The genetic variation associated with FXS affects white matter microstructure independently of overall IQ. White matter differences, found in FXS relative to IQ-matched controls, are distinct from reported differences relative to neurotypical controls. This underscores the need to consider cognitive ability differences when investigating white matter microstructure in neurodevelopmental disorders.


Assuntos
Encefalopatias/patologia , Proteína do X Frágil da Deficiência Intelectual/genética , Síndrome do Cromossomo X Frágil/patologia , Substância Branca/patologia , Análise de Variância , Anisotropia , Estudos de Casos e Controles , Imagem de Tensor de Difusão , Feminino , Síndrome do Cromossomo X Frágil/genética , Humanos , Inteligência/genética , Masculino , Fenótipo , Estudos Prospectivos , Adulto Jovem
16.
J Alzheimers Dis ; 97(1): 327-343, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38043011

RESUMO

BACKGROUND: Cognitive training holds potential as a non-pharmacological intervention to decrease cognitive symptoms associated with Alzheimer's disease (AD), but more research is needed to understand individual differences that may predict maximal training benefits. OBJECTIVE: We conducted a pilot study using a six-month training regimen in healthy aging adults with no cognitive decline. We investigated the effects of baseline performance and age on training and transfer improvements. METHODS: Out of 43 participants aged 65-84 years, 31 successfully completed cognitive training (BrainHQ) in one of three cognitive domains: processing speed (N = 13), inhibitory control (N = 9), or episodic memory (N = 9). We used standardized assessments to measure baseline performance and transfer effects. RESULTS: All 31 participants improved on the cognitive training regimen and age was positively associated with training improvement (p = 0.039). The processing speed group improved significantly across many near- and far-transfer tasks. In the inhibitory control group, individuals with lower baseline performance improved more on inhibitory control and cognitive flexibility tasks. In the episodic memory group, older individuals improved most on a memory task while younger individuals improved most on an executive function far-transfer task. CONCLUSIONS: Individual differences are predictive of cognitive training gains, and the impact of individual differences on training improvements is specific to the domain of training. We provide initial insight regarding how non-pharmacological interventions can be optimized to combat the onset of cognitive decline in older adults. With future research this work can inform the design of effective cognitive interventions for delaying cognitive decline in preclinical AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Idoso , Projetos Piloto , Memória de Curto Prazo , Treino Cognitivo , Função Executiva , Disfunção Cognitiva/terapia , Cognição
17.
Artigo em Inglês | MEDLINE | ID: mdl-38621478

RESUMO

BACKGROUND: RASopathies are a group of disorders characterized by pathogenic mutations in the Ras/mitogen-activated protein kinase (Ras/MAPK) signaling pathway. Distinct pathogenic variants in genes encoding proteins in the Ras/MAPK pathway cause Noonan syndrome (NS) and neurofibromatosis type 1 (NF1), which are associated with increased risk for autism spectrum disorder and attention-deficit/hyperactivity disorder. METHODS: This study examined the effect of RASopathies (NS and NF1) on human neuroanatomy, specifically on surface area (SA), cortical thickness (CT), and subcortical volumes. Using vertex-based analysis for cortical measures and Desikan region of interest parcellation for subcortical volumes, we compared structural T1-weighted images of children with RASopathies (n = 91, mean age = 8.81 years, SD = 2.12) to those of sex- and age-matched typically developing children (n = 74, mean age = 9.07 years, SD = 1.77). RESULTS: Compared with typically developing children, RASopathies had convergent effects on SA and CT, exhibiting increased SA in the precentral gyrus, decreased SA in occipital regions, and thinner CT in the precentral gyrus. RASopathies exhibited divergent effects on subcortical volumes, with syndrome-specific influences from NS and NF1. Overall, children with NS showed decreased volumes in striatal and thalamic structures, and children with NF1 displayed increased volumes in the hippocampus, amygdala, and thalamus. CONCLUSIONS: Our study reveals the converging and diverging neuroanatomical effects of RASopathies on human neurodevelopment. The convergence of cortical effects on SA and CT indicates a shared influence of Ras/MAPK hyperactivation on the human brain. Therefore, considering these measures as objective outcome indicators for targeted treatments is imperative.

18.
Artigo em Inglês | MEDLINE | ID: mdl-34555563

RESUMO

BACKGROUND: Children and adolescents with fragile X syndrome (FXS) manifest significant symptoms of anxiety, particularly in response to face-to-face social interaction. In this study, we used functional near-infrared spectroscopy to reveal a specific pattern of brain activation and habituation in response to face stimuli in young girls with FXS, an important but understudied clinical population. METHODS: Participants were 32 girls with FXS (age: 11.8 ± 2.9 years) and a control group of 28 girls without FXS (age: 10.5 ± 2.3 years) matched for age, general cognitive function, and autism symptoms. Functional near-infrared spectroscopy was used to assess brain activation during a face habituation task including repeated upright/inverted faces and greeble (nonface) objects. RESULTS: Compared with the control group, girls with FXS showed significant hyperactivation in the frontopolar and dorsal lateral prefrontal cortices in response to all face stimuli (upright + inverted). Lack of neural habituation (and significant sensitization) was also observed in the FXS group in the frontopolar cortex in response to upright face stimuli. Finally, aberrant frontopolar sensitization in response to upright faces in girls with FXS was significantly correlated with notable cognitive-behavioral and social-emotional outcomes relevant to this condition, including executive function, autism symptoms, depression, and anxiety. CONCLUSIONS: These findings strongly support a hypothesis of neural hyperactivation and accentuated sensitization during face processing in FXS, a phenomenon that could be developed as a biomarker end point for improving treatment trial evaluation in girls with this condition.


Assuntos
Reconhecimento Facial , Síndrome do Cromossomo X Frágil , Criança , Feminino , Adolescente , Humanos , Síndrome do Cromossomo X Frágil/psicologia , Encéfalo , Córtex Cerebral , Biomarcadores
19.
J Appl Biomech ; 28(3): 343-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21908899

RESUMO

The goal of this study was to evaluate the performance of a single video camera system for measuring shoulder rotation during computer work, and to quantify the work and postural space within which the system performs optimally. Shoulder rotation angles calculated using the video system were compared with angles calculated using an active infrared LED three-dimensional motion analysis system while 10 adult volunteers simulated postures for two different trials: typical of normal computer work (freestyle) and with forced shoulder abduction (constrained). Average and absolute errors were calculated to determine the accuracy and precision of the system, respectively, for each trial, for each position, and for both the right and left hands. For the right hand, mean values for the average and absolute errors were -1 and 0 degrees, respectively. Only the absolute error increased significantly to 12 degrees for the constrained posture compared with freestyle. During normal computer work, the video system provided shoulder rotation angle values similar to those of a three-dimensional system, thus making it a viable and simple instrument to use in field studies.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Movimento/fisiologia , Fotografação/métodos , Postura/fisiologia , Amplitude de Movimento Articular/fisiologia , Articulação do Ombro/fisiologia , Gravação em Vídeo/métodos , Adulto , Feminino , Humanos , Masculino
20.
J Autism Dev Disord ; 52(5): 2213-2223, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34081299

RESUMO

We tested whether empathy is impaired and associated with anxiety in girls with fragile X syndrome (FXS). We measured parent-reported empathy and self-reported anxiety in young girls with FXS and in a developmentally-matched comparison group. Girls with FXS received higher parent-reported scores on cognitive and affective empathy but also self-reported more severe anxiety symptoms, particularly separation anxiety and phobia symptoms, than girls in the comparison group. Girls with FXS who received higher cognitive empathy scores, however, appeared buffered against risk for separation anxiety and phobia symptoms. Girls with FXS experience elevated empathy and anxiety relative to their developmentally-matched peers. Higher cognitive empathy in girls with FXS may indicate resilience against specific forms of anxiety that are commonly observed in FXS.


Assuntos
Transtorno do Espectro Autista , Síndrome do Cromossomo X Frágil , Ansiedade , Transtornos de Ansiedade/psicologia , Transtorno do Espectro Autista/complicações , Empatia , Feminino , Síndrome do Cromossomo X Frágil/psicologia , Humanos
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