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1.
PLoS One ; 16(4): e0249326, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33905429

RESUMO

We created a novel social feedback paradigm to study how motivation for potential social links is influenced in adolescents and adults. 88 participants (42F/46M) created online posts and then expended physical effort to show their posts to other users, who varied in number of followers and probability of positive feedback. We focused on two populations of particular interest from a social feedback perspective: adolescents relative to young adults (13-17 vs 18-24 years of age), and participants with social anxiety symptoms. Individuals with higher self-reported symptoms of social anxiety did not follow the typical pattern of increased effort to obtain social feedback from high status peers. Adolescents were more willing to exert physical effort on the task than young adults. Overall, participants were more likely to exert physical effort for high social status users and for users likely to yield positive feedback, and men were more likely to exert effort than women, findings that parallel prior results in effort-based tasks with financial rather than social rewards. Together the findings suggest social motivation is malleable, driven by factors of social status and the likelihood of a positive social outcome, and that age, sex, and social anxiety significantly impact patterns of socially motivated decision-making.


Assuntos
Ansiedade/psicologia , Retroalimentação Psicológica , Motivação , Adolescente , Feminino , Humanos , Masculino , Adulto Jovem
2.
Neurosci Biobehav Rev ; 120: 249-261, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33246019

RESUMO

Deficiencies in Theory of Mind (ToM) are consistently found in individuals with schizophrenia (SZ), major depressive disorder (MDD), and bipolar disorder (BD). However, the character of these deficits and their role in the pathogenesis of mental illness remains poorly understood. This systematic review synthesizes the available secondary literature pertaining to ToM functioning in individuals with MDD, BD, or SZ, and their respective spectrum disorders in order to delineate disorder or symptom specific patterns of ToM impairment. Literature suggests that ToM deficits increase in severity along the affective-psychotic spectrum, with mild deficits in patients with MDD, and severe deficits in patients with mania or psychosis. Furthermore, ToM deficits appear to be part of a broader developmental phenotype associated with SZ and BD, as suggested by findings of attenuated impairments in ToM in remitted patients with SZ or BD, unaffected first-degree relatives of patients, and clinical high-risk groups. Future psychiatric research on ToM should aim to disentangle relationships between ToM deficits and specific symptom dimensions transdiagnostically, and employ standardized, construct-specific ToM tasks.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Esquizofrenia , Teoria da Mente , Humanos , Testes Neuropsicológicos , Esquizofrenia/complicações
3.
Dev Cogn Neurosci ; 45: 100829, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32738778

RESUMO

Self-regulation is the ability to monitor and modulate emotions, behaviour, and cognition in order to adapt to changing circumstances. Developing adequate self-regulation is associated with better social coping and higher educational achievement later in life; poor self-regulation has been linked to a variety of detrimental developmental outcomes. Here, we focus on the development of neurocognitive processes essential for self-regulation. We outline a conceptual framework emphasizing that this is inherently an integrated, dynamic process involving interactions between brain maturation, child characteristics (genetic makeup, temperament, and pre- and perinatal factors) and environmental factors (family characteristics, parents and siblings, peers, and broader societal influences including media development). We introduce the Consortium of Individual Development (CID), which combines a series of integrated large-scale, multi-modal, longitudinal studies to take essential steps towards the ultimate goal of understanding and supporting this process.


Assuntos
Terapia Combinada/métodos , Transtornos Neurocognitivos/psicologia , Autocontrole/psicologia , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino
4.
Dev Psychobiol ; 62(5): 591-599, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31802483

RESUMO

Adolescence is a developmental period of increased sensitivity to social emotional cues, but it is less known whether young adults demonstrate similar social emotional sensitivity. The current study tested variation in reaction times to emotional face cues during different phases of emotional development. Ex-Gaussian parameters mu, sigma, and tau were computed, in addition to mean, median and standard deviation (SD) in reaction times (RT) during an emotional go/nogo-paradigm with fearful, happy, and calm facial expressions in 377 participants, 6-30 years of age. Across development, mean RT showed slowing to fearful facial expressions relative to both calm and happy facial cues, but mu revealed that this pattern was specific to adolescence. In young adulthood, increased variability to fearful expressions relative to both happy and calm ones was captured by SD and tau. The findings that adolescents had longer response latencies to fearful faces, whereas young adults demonstrated greater response variability to fearful faces, together reflect how social emotional processing continues to evolve from adolescence into early adulthood. The findings suggest that young adulthood is also a vulnerable period for processing social emotional cues that ultimately may be important to better understand why different psychopathologies emerge in early adulthood.


Assuntos
Emoções/fisiologia , Adolescente , Adulto , Comportamento/fisiologia , Criança , Sinais (Psicologia) , Expressão Facial , Reconhecimento Facial/fisiologia , Medo , Feminino , Felicidade , Humanos , Masculino , Tempo de Reação , Autocontrole/psicologia , Adulto Jovem
5.
J Autism Dev Disord ; 50(1): 364-372, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31625010

RESUMO

Differences in motivation during adolescence relative to childhood and adulthood in autism was tested in a cross-sectional study. 156 Typically developing individuals and 79 individuals with autism ages 10-30 years of age completed a go/nogo task with social and non-social cues. To assess age effects, linear and quadratic models were used. Consistent with prior studies, typically developing adolescents and young adults demonstrated more false alarms for positive relative to neutral social cues. In autism, there were no changes in attention across age for social or non-social cues. Findings suggest reduced orienting to motivating cues during late adolescence and early adulthood in autism. The findings provide a unique perspective to explain the challenges for adolescents with autism transitioning to adulthood.


Assuntos
Desenvolvimento do Adolescente , Atenção , Transtorno Autístico/psicologia , Motivação , Adolescente , Adulto , Criança , Estudos Transversais , Sinais (Psicologia) , Feminino , Humanos , Modelos Lineares , Masculino , Orientação , Análise e Desempenho de Tarefas , Adulto Jovem
6.
J Abnorm Psychol ; 128(5): 431-441, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31045398

RESUMO

The present study tested whether salient affective cues would negatively influence cognitive control in children with and without autism spectrum disorder (ASD). One hundred children aged 6-12 years who were either typically developing or had ASD performed a novel go/no-go task to cues of their interest versus cues of noninterest. Linear mixed-effects (LME) models for hit rate, false alarms, and the sensitivity index d' were used to test for group differences. Caregivers completed the Repetitive Behavior Scale-Revised to test associations between repetitive behaviors and task performance. Children with ASD had reduced cognitive control toward their interests compared with typically developing children. Further, children with ASD showed reduced cognitive control to interests compared with noninterests, a pattern not observed in typically developing children. Decreased cognitive control toward interests was associated with higher insistence on sameness behavior in ASD, but there was no association between sameness behavior and cognitive control for noninterests. Together, children with ASD demonstrated decreased cognitive flexibility in the context of increased affective salience related to interests. These results provide a mechanism for how salient affective cues, such as interests, interfere with daily functioning and social communication in ASD. Further, the findings have broader clinical implications for understanding how affective cues can drive interactions between restricted patterns of behavior and cognitive control. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Sinais (Psicologia) , Emoções/fisiologia , Função Executiva/fisiologia , Criança , Feminino , Humanos , Masculino
7.
Neuroimage ; 189: 141-149, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30639840

RESUMO

Head motion causes artifacts in functional magnetic resonance imaging (fMRI) scans, a problem especially relevant for task-free resting state paradigms and for developmental, aging, and clinical populations. In a cohort spanning 7-28 years old (mean age 15) we produced customized head-anatomy-specific Styrofoam molds for each subject that inserted into an MRI head coil. We scanned these subjects under two conditions: using our standard procedure of packing the head coil with foam padding about the head to reduce head motion, and using the customized molds to reduce head motion. In 12 of 13 subjects, the molds reduced head motion throughout the scan and reduced the fraction of a scan with substantial motion (i.e., volumes with motion notably above baseline levels of motion). Motion was reduced in all 6 head position estimates, especially in rotational, left-right, and superior-inferior directions. Motion was reduced throughout the full age range studied, including children, adolescents, and young adults. In terms of the fMRI data itself, quality indices improved with the head mold on, scrubbing analyses detected less distance-dependent artifact in scans with the head mold on, and distant-dependent artifact was less evident in both the entire scan and also during only low-motion volumes. Subjects found the molds comfortable. Head molds are thus effective tools for reducing head motion, and motion artifacts, during fMRI scans.


Assuntos
Neuroimagem Funcional/normas , Movimentos da Cabeça , Imageamento por Ressonância Magnética/normas , Restrição Física/instrumentação , Adolescente , Adulto , Criança , Desenho de Equipamento/normas , Feminino , Humanos , Masculino , Poliestirenos , Adulto Jovem
8.
Dev Cogn Neurosci ; 36: 100602, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30559053

RESUMO

Repetitive behaviors are among the core symptoms of both Autism Spectrum Disorder (ASD) and Obsessive-Compulsive Disorder (OCD) and are thought to be associated with impairments in cognitive control. However, it is still unknown how deficits in cognitive control and associated neural circuitry relate to the quality or severity of repetitive behavior in children with these disorders. Therefore, we investigated the behavioral and neural correlates of cognitive control using a modified stop-signal task in a multicenter study of children (aged 8-12 years) with ASD, OCD and typically developing (TD) children (N = 95). As both ASD and OCD have high levels of comorbidity with Attention Deficit/Hyperactivity Disorder (ADHD), we did an exploratory analysis addressing ADHD-symptoms. We found that children with ASD and OCD did not show deficits in cognitive control or changes in brain activity in task-relevant neural networks when compared to TD children. However, increased activity in prefrontal brain areas was associated with increased symptoms of comorbid ADHD. As such, this study does not support differences in cognitive control or associated neural circuitry in children with ASD and OCD, but rather suggests that changes in cognitive control in these disorders may be related to symptoms of comorbid ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtorno do Espectro Autista/psicologia , Cognição/fisiologia , Transtorno Obsessivo-Compulsivo/psicologia , Criança , Comorbidade , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
9.
Soc Cogn Affect Neurosci ; 12(12): 1890-1901, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29077964

RESUMO

The activities we choose to spend our leisure time with are intrinsically motivating and vary across individuals. Yet it is unknown how impulse control or neural activity changes when processing a preferred stimulus related to a hobby or interest. Developing a task that assesses the response to preferred interests is of importance as it would be relevant to a range of psychiatric disorders that have hyper- or hypo-arousal to such cues. During functional Magnetic Resonance Imaging (fMRI), 39 healthy adults completed a novel task to test approach behavior and cognitive control to cues that were personalized to the participants' interests compared to stimuli the participants identified as being of non-interest and colored shapes. fMRI results showed that cues of one's interest elicited activation in the anterior insula compared to colored shapes. Interests did not change inhibition compared to non-interests and colored shapes and all stimuli equally engaged a frontostriatal circuit. Together the results suggest that adults were sensitive to their interests but were effective at regulating their impulses towards these cues, a skill that is critical for navigating the temptations and distractions in our daily environment.


Assuntos
Comportamento Impulsivo , Atividades de Lazer/psicologia , Adolescente , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtorno do Espectro Autista/psicologia , Cognição , Sinais (Psicologia) , Expressão Facial , Feminino , Lobo Frontal/fisiologia , Passatempos/psicologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Neostriado/fisiologia , Vias Neurais/fisiologia , Testes Neuropsicológicos , Estimulação Luminosa , Reprodutibilidade dos Testes , Adulto Jovem
10.
J Child Psychol Psychiatry ; 58(7): 810-818, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28295280

RESUMO

BACKGROUND: Attention deficit/hyperactivity disorder (ADHD) has frequently been associated with changes in resting-state functional connectivity, and decreased white matter (WM) integrity. In the current study, we investigated functional connectivity within Default Mode and frontal control resting-state networks (RSNs) in children with and without ADHD. We hypothesized the RSNs of interest would show a pattern of impaired functional integration and segregation and corresponding changes in WM structure. METHODS: Resting-state fMRI and diffusion-weighted imaging data were acquired from 35 participants with ADHD and 36 matched typically developing peers, aged 6 through 18 years. Functional connectivity was assessed using independent component analysis. Network topology and WM connectivity were further investigated using graph theoretical measures and tract-based spatial statistics (TBSS). RESULTS: Resting-state fMRI analyses showed increased functional connectivity in right inferior frontal gyrus (IFG), and bilateral medial prefrontal cortex (mPFC) within the Default Mode and frontal control networks. Furthermore, a more diffuse spatial pattern of functional connectivity was found in children with ADHD. We found no group differences in structural connectivity as assessed with TBSS or graph theoretical measures. CONCLUSIONS: Resting-state networks show a more diffuse pattern of connectivity in children with ADHD. The increases in functional connectivity in right IFG and bilateral mPFC in children with ADHD may reflect reduced or delayed functional segregation of prefrontal brain regions. As these functional changes were not accompanied by changes in WM, they may precede the development of the frequently reported changes in WM structure.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Conectoma/métodos , Córtex Pré-Frontal/fisiopatologia , Substância Branca/diagnóstico por imagem , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Criança , Imagem de Tensor de Difusão , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem
11.
J Child Psychol Psychiatry ; 58(2): 206-214, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27678006

RESUMO

BACKGROUND: Changes in reward processing are thought to be involved in the etiology of attention-deficit/hyperactivity disorder (ADHD), as well as other developmental disorders. In addition, different forms of therapy for ADHD rely on reinforcement principles. As such, improved understanding of reward processing in ADHD could eventually lead to more effective treatment options. However, differences in reward processing may not be specific to ADHD, but may be a trans-diagnostic feature of disorders that involve ADHD-like symptoms. METHODS: In this event-related fMRI study, we used a child-friendly version of the monetary incentive delay task to assess performance and brain activity during reward anticipation. Also, we collected questionnaire data to assess reward sensitivity in daily life. For final analyses, data were available for 27 typically developing children, 24 children with ADHD, and 25 children with an autism spectrum disorder (ASD) and ADHD symptoms. RESULTS: We found decreased activity in ventral striatum during anticipation of reward in children with ADHD symptoms, both for children with ADHD as their primary diagnosis and in children with autism spectrum disorder and ADHD symptoms. We found that higher parent-rated sensitivity to reward was associated with greater anticipatory activity in ventral striatum for children with ADHD symptoms. In contrast, there was no relationship between the degree of ADHD symptoms and activity in ventral striatum. CONCLUSIONS: We provide evidence of biological and behavioral differences in reward sensitivity in children with ADHD symptoms, regardless of their primary diagnosis. Ultimately, a dimensional brain-behavior model of reward sensitivity in children with symptoms of ADHD may be useful to refine treatment options dependent on reward processing.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Transtorno do Espectro Autista/fisiopatologia , Comportamento Infantil/fisiologia , Recompensa , Estriado Ventral/fisiopatologia , Antecipação Psicológica , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Espectro Autista/epidemiologia , Mapeamento Encefálico , Criança , Comorbidade , Humanos , Imageamento por Ressonância Magnética , Masculino
12.
Eur Neuropsychopharmacol ; 26(3): 546-61, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26742901

RESUMO

Public opinion and media coverage suggest that there are benefits of long-chain ω-3 polyunsaturated fatty acid (LC-PUFA) intake on brain functioning. However, it is an open question whether this is indeed the case. Therefore, we reviewed the evidence for effects of ω-3 LC-PUFA on human brain morphology and function. We included studies on (1) naturalistic long-term ω-3 LC-PUFA intake during life (2) the effects of short-term ω-3 LC-PUFA supplementation in healthy subjects and (3) the effects of ω-3 LC-PUFA supplementation as alternative or add-on treatment for psychiatric or neurological disorders. To date, 24 studies have been published on the effect of ω-3 LC-PUFA on brain function and structure. Findings from naturalistic studies and clinical trials in healthy individuals indicate that ω-3 LC-PUFA intake may be associated with increased functional activation of the prefrontal cortex in children, and greater gray matter volume and white matter integrity during aging. However, most naturalistic studies were cross-sectional or did not find any effect on cognition. As such, it is hard to estimate the magnitude of any beneficial effects. Furthermore, there is only limited evidence to support that ω-3 LC-PUFA supplementation is beneficial in brain disorders, such as Alzheimer's Disease, Attention Deficit/Hyperactivity Disorder, Major Depressive Disorder and schizophrenia. Overall, the literature suggests that sensitivity to supplementation may vary over development, and as a consequence of brain disorders. The biological mechanisms underlying any (beneficial) effects ω-3 LC-PUFAs on the brain are currently unknown and need to be investigated.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Ácidos Graxos Ômega-3/metabolismo , Encefalopatias/patologia , Encefalopatias/fisiopatologia , Encefalopatias/prevenção & controle , Bases de Dados Bibliográficas/estatística & dados numéricos , Suplementos Nutricionais , Feminino , Humanos , Masculino
13.
PLoS One ; 10(11): e0142413, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26599542

RESUMO

Reward processing has been implicated in developmental disorders. However, the classic task to probe reward anticipation, the monetary incentive delay task, has an abstract coding of reward and no storyline and may therefore be less appropriate for use with developmental populations. We modified the task to create a version appropriate for use with children. We investigated whether this child-friendly version could elicit ventral striatal activation during reward anticipation in typically developing children and young adolescents (aged 9.5-14.5). In addition, we tested whether our performance-based measure of reward sensitivity was associated with anticipatory activity in ventral striatum. Reward anticipation was related to activity in bilateral ventral striatum. Moreover, we found an association between individual reward sensitivity and activity in ventral striatum. We conclude that this task assesses ventral striatal activity in a child-friendly paradigm. The combination with a performance-based measure of reward sensitivity potentially makes the task a powerful tool for developmental imaging studies of reward processing.


Assuntos
Imageamento por Ressonância Magnética , Recompensa , Estriado Ventral/patologia , Adolescente , Antecipação Psicológica/fisiologia , Mapeamento Encefálico/métodos , Criança , Feminino , Humanos , Masculino , Motivação , Projetos Piloto , Tempo de Reação/fisiologia , Estriado Ventral/fisiologia
14.
J Am Acad Child Adolesc Psychiatry ; 54(8): 668-76, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26210336

RESUMO

OBJECTIVE: Autism spectrum disorders (ASD) have been associated with atypical cortical gray and subcortical white matter development. Neurodevelopmental theories postulate that a relation between cortical maturation and structural brain connectivity may exist. We therefore investigated the development of gyrification and white matter connectivity and their relationship in individuals with ASD and their typically developing peers. METHOD: T1- and diffusion-weighted images were acquired from a representative sample of 30 children and adolescents with ASD (aged 8-18 years), and 29 typically developing children matched for age, sex, hand preference, and socioeconomic status. The FreeSurfer suite was used to calculate cortical volume, surface area, and gyrification index. Measures of structural connectivity were estimated using probabilistic tractography and tract-based spatial statistics (TBSS). RESULTS: Left prefrontal and parietal cortex showed a relative, age-dependent decrease in gyrification index in children and adolescents with ASD compared to typically developing controls. This result was replicated in an age-and IQ-matched sample provided by the Autism Brain Imaging Data Exchange (ABIDE) initiative. Furthermore, tractography and TBSS showed a complementary pattern in which left prefrontal gyrification was negatively related to radial diffusivity in the forceps minor in participants with ASD. CONCLUSION: The present study builds on earlier findings of abnormal gyrification and structural connectivity in the prefrontal cortex in ASD. It provides a more comprehensive neurodevelopmental characterization of ASD, involving interdependent changes in microstructural white and cortical gray matter. The findings of related abnormal patterns of gyrification and white matter connectivity support the notion of the intertwined development of 2 major morphometric domains in ASD.


Assuntos
Transtorno do Espectro Autista/patologia , Córtex Cerebral/patologia , Adolescente , Transtorno do Espectro Autista/fisiopatologia , Estudos de Casos e Controles , Córtex Cerebral/fisiopatologia , Criança , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Masculino , Vias Neurais/patologia , Vias Neurais/fisiopatologia , Neuroimagem , Lobo Parietal/patologia , Lobo Parietal/fisiopatologia , Córtex Pré-Frontal/patologia , Córtex Pré-Frontal/fisiopatologia
15.
Neuropsychopharmacology ; 40(10): 2298-306, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25790022

RESUMO

Attention deficit/hyperactivity disorder (ADHD) is one of the most common child psychiatric disorders, and is often treated with stimulant medication. Nonpharmacological treatments include dietary supplementation with omega-3 fatty acids, although their effectiveness remains to be shown conclusively. In this study, we investigated the effects of dietary omega-3 fatty acid supplementation on ADHD symptoms and cognitive control in young boys with and without ADHD. A total of 40 boys with ADHD, aged 8-14 years, and 39 matched, typically developing controls participated in a 16-week double-blind randomized placebo-controlled trial. Participants consumed 10 g of margarine daily, enriched with either 650 mg of eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA) each or placebo. Baseline and follow-up assessments addressed ADHD symptoms, fMRI of cognitive control, urine homovanillic acid, and cheek cell phospholipid sampling. EPA/DHA supplementation improved parent-rated attention in both children with ADHD and typically developing children. Phospholipid DHA level at follow-up was higher for children receiving EPA/DHA supplements than placebo. There was no effect of EPA/DHA supplementation on cognitive control or on fMRI measures of brain activity. This study shows that dietary supplementation with omega-3 fatty acids reduces symptoms of ADHD, both for individuals with ADHD and typically developing children. This effect does not appear to be mediated by cognitive control systems in the brain, as no effect of supplementation was found here. Nonetheless, this study offers support that omega-3 supplementation may be an effective augmentation for pharmacological treatments of ADHD (NCT01554462: The Effects of EPA/DHA Supplementation on Cognitive Control in Children with ADHD; http://clinicaltrials.gov/show/NCT01554462).


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/dietoterapia , Suplementos Nutricionais , Ácidos Graxos Ômega-3/uso terapêutico , Adolescente , Análise de Variância , Transtorno do Deficit de Atenção com Hiperatividade/patologia , Transtorno do Deficit de Atenção com Hiperatividade/urina , Encéfalo/irrigação sanguínea , Estudos de Casos e Controles , Criança , Ácidos Docosa-Hexaenoicos/administração & dosagem , Método Duplo-Cego , Ácido Eicosapentaenoico/administração & dosagem , Seguimentos , Ácido Homovanílico , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Margarina , Testes Neuropsicológicos , Oxigênio/sangue , Inquéritos e Questionários , Resultado do Tratamento
16.
Neuroimage Clin ; 7: 132-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25610775

RESUMO

ADHD is characterized by increased intra-individual variability in response times during the performance of cognitive tasks. However, little is known about developmental changes in intra-individual variability, and how these changes relate to cognitive performance. Twenty subjects with ADHD aged 7-24 years and 20 age-matched, typically developing controls participated in an fMRI-scan while they performed a go-no-go task. We fit an ex-Gaussian distribution on the response distribution to objectively separate extremely slow responses, related to lapses of attention, from variability on fast responses. We assessed developmental changes in these intra-individual variability measures, and investigated their relation to no-go performance. Results show that the ex-Gaussian measures were better predictors of no-go performance than traditional measures of reaction time. Furthermore, we found between-group differences in the change in ex-Gaussian parameters with age, and their relation to task performance: subjects with ADHD showed age-related decreases in their variability on fast responses (sigma), but not in lapses of attention (tau), whereas control subjects showed a decrease in both measures of variability. For control subjects, but not subjects with ADHD, this age-related reduction in variability was predictive of task performance. This group difference was reflected in neural activation: for typically developing subjects, the age-related decrease in intra-individual variability on fast responses (sigma) predicted activity in the dorsal anterior cingulate gyrus (dACG), whereas for subjects with ADHD, activity in this region was related to improved no-go performance with age, but not to intra-individual variability. These data show that using more sophisticated measures of intra-individual variability allows the capturing of the dynamics of task performance and associated neural changes not permitted by more traditional measures.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Encéfalo/fisiopatologia , Individualidade , Adolescente , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
17.
Neuroimage Clin ; 4: 820-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24936432

RESUMO

OBJECTIVE: Autism Spectrum Disorder (ASD) has been associated with a complex pattern of increases and decreases in resting-state functional connectivity. The developmental disconnection hypothesis of ASD poses that shorter connections become overly well established with development in this disorder, at the cost of long-range connections. Here, we investigated resting-state connectivity in relatively young boys with ASD and typically developing children. We hypothesized that ASD would be associated with reduced connectivity between networks, and increased connectivity within networks, reflecting poorer integration and segregation of functional networks in ASD. METHODS: We acquired resting-state fMRI from 27 boys with ASD and 29 age- and IQ-matched typically developing boys between 6 and 16 years of age. Functional connectivity networks were identified using Independent Component Analysis (ICA). Group comparisons were conducted using permutation testing, with and without voxel-wise correction for grey matter density. RESULTS: We found no between-group differences in within-network connectivity. However, we did find reduced functional connectivity between two higher-order cognitive networks in ASD. Furthermore, we found an interaction effect with age in the DMN: insula connectivity increased with age in ASD, whereas it decreased in typically developing children. CONCLUSIONS: These results show subtle changes in between network connectivity in relatively young boys with ASD. However, the global architecture of resting-state networks appeared to be intact. This argues against recent suggestions that changes in connectivity in ASD may be the most prominent during development.


Assuntos
Encéfalo/patologia , Transtornos Globais do Desenvolvimento Infantil/complicações , Transtornos Globais do Desenvolvimento Infantil/patologia , Deficiências do Desenvolvimento/etiologia , Vias Neurais/patologia , Descanso , Adolescente , Encéfalo/irrigação sanguínea , Mapeamento Encefálico , Criança , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/patologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/irrigação sanguínea , Rede Nervosa/patologia , Vias Neurais/irrigação sanguínea , Oxigênio/sangue , Análise de Componente Principal
18.
Biol Psychiatry ; 76(5): 405-11, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-24090791

RESUMO

BACKGROUND: Repetitive behavior is a core feature of autism and has been linked to differences in striatum. In addition, the brain changes associated with autism appear to vary with age. However, most studies investigating striatal differences in autism are cross-sectional, limiting inferences on development. In this study, we set out to 1) investigate striatal development in autism, using a longitudinal design; and 2) examine the relationship between striatal development and repetitive behavior. METHODS: We acquired longitudinal structural magnetic resonance imaging scans from 86 individuals (49 children with autism, 37 matched control subjects). Each individual was scanned twice, with a mean scan interval time of 2.4 years. Mean age was 9.9 years at time 1 and 12.3 years at time 2. Striatal structures were traced manually with high reliability. Multivariate analyses of variance were used to investigate differences in brain development between diagnostic groups. To examine the relationship with behavior, correlations between changes in brain volumes and clinical measures were calculated. RESULTS: Our results showed an increase in the growth rate of striatal structures for individuals with autism compared with control subjects. The effect was specific to caudate nucleus, where growth rate was doubled. Second, faster striatal growth was correlated with more severe repetitive behavior (insistence on sameness) at the preschool age. CONCLUSIONS: This longitudinal study of brain development in autism confirms the involvement of striatum in repetitive behavior. Furthermore, it underscores the significance of brain development in autism, as the severity of repetitive behavior was related to striatal growth, rather than volume per se.


Assuntos
Transtorno Autístico/patologia , Corpo Estriado/crescimento & desenvolvimento , Corpo Estriado/patologia , Comportamento Estereotipado , Adolescente , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Criança , Feminino , Lateralidade Funcional , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Análise Multivariada , Tamanho do Órgão
19.
Biol Psychiatry ; 68(12): 1114-9, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20926067

RESUMO

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is characterized by poor optimization of behavior in the face of changing demands. Theoretical accounts of ADHD have often focused on higher-order cognitive processes and typically assume that basic processes are unaffected. It is an open question whether this is indeed the case. METHOD: We explored basic cognitive processing in 25 subjects with ADHD and 30 typically developing children and adolescents with a perceptual decision-making paradigm. We investigated whether individuals with ADHD were able to balance the speed and accuracy of decisions. RESULTS: We found impairments in the optimization of the speed-accuracy tradeoff. Furthermore, these impairments were directly related to the hyperactive and impulsive symptoms that characterize the ADHD-phenotype. CONCLUSIONS: These data suggest that impairments in basic cognitive processing are central to the disorder. This calls into question conceptualizations of ADHD as a "higher-order" deficit, as such simple decision processes are at the core of almost every paradigm used in ADHD research.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Tomada de Decisões/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Criança , Feminino , Humanos , Masculino , Modelos Psicológicos
20.
Biol Psychiatry ; 66(4): 327-33, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19423078

RESUMO

BACKGROUND: Repetitive and stereotyped behavior has been associated with striatum in various neuropsychiatric disorders. However, striatal involvement has not yet been shown conclusively in autism. Issues include the use of neuroleptic medication and differences in mean age between samples, where conflicting results may reflect differences in developmental stage between samples. The objective was to examine brain development in a homogeneous sample of subjects with high-functioning autism. METHODS: Magnetic resonance measures of brain structure of 188 individuals (99 subjects with high-functioning autism and 89 typically developing, matched control subjects) aged between 6 years and 25 years were compared. Measurements included the volume of brain structures, including striatum, as well as voxel-based assessment of gray matter density. RESULTS: Developmental trajectories of the caudate nucleus, putamen, and nucleus accumbens differed between subjects with autism and control subjects. Results were not accounted for by overall changes in brain volume or neuroleptic medication. The development of the caudate nucleus differed from typical most, as its volume increased with age in autism, while it decreased for control subjects. Voxel-based analysis showed that changes in striatum localized to the head of the caudate nucleus. Overall, caudate nucleus volume was associated with repetitive behavior in autism. CONCLUSIONS: We report changes in striatal development in autism, while caudate volume is associated with repetitive behaviors. This emphasizes the importance of striatum in the etiology of autism, in particular in the development of repetitive behavior that characterizes the disorder.


Assuntos
Envelhecimento , Transtorno Autístico/patologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Corpo Estriado/crescimento & desenvolvimento , Corpo Estriado/patologia , Adolescente , Adulto , Transtorno Autístico/fisiopatologia , Encéfalo/fisiopatologia , Estudos de Casos e Controles , Criança , Corpo Estriado/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Tamanho do Órgão , Comportamento Estereotipado/fisiologia
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