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1.
Psychiatry Res ; 202(3): 239-44, 2012 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-22819939

RESUMO

Youths with conduct disorder or oppositional defiant disorder and psychopathic traits (CD/ODD+PT) are at high risk of adult antisocial behavior and psychopathy. Neuroimaging studies demonstrate functional abnormalities in orbitofrontal cortex and the amygdala in both youths and adults with psychopathic traits. Diffusion tensor imaging in psychopathic adults demonstrates disrupted structural connectivity between these regions (uncinate fasiculus). The current study examined whether functional neural abnormalities present in youths with CD/ODD+PT are associated with similar white matter abnormalities. Youths with CD/ODD+PT and comparison participants completed 3.0 T diffusion tensor scans and functional magnetic resonance imaging scans. Diffusion tensor imaging did not reveal disruption in structural connections within the uncinate fasiculus or other white matter tracts in youths with CD/ODD+PT, despite the demonstration of disrupted amygdala-prefrontal functional connectivity in these youths. These results suggest that disrupted amygdala-frontal white matter connectivity as measured by fractional anisotropy is less sensitive than imaging measurements of functional perturbations in youths with psychopathic traits. If white matter tracts are intact in youths with this disorder, childhood may provide a critical window for intervention and treatment, before significant structural brain abnormalities solidify.


Assuntos
Transtornos de Deficit da Atenção e do Comportamento Disruptivo/patologia , Mapeamento Encefálico , Transtorno da Conduta/patologia , Sistema Límbico/patologia , Fibras Nervosas Mielinizadas/patologia , Adolescente , Análise de Variância , Anisotropia , Transtorno da Personalidade Antissocial/complicações , Transtorno da Personalidade Antissocial/patologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/complicações , Estudos de Casos e Controles , Criança , Transtorno da Conduta/complicações , Imagem de Tensor de Difusão , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Escalas de Graduação Psiquiátrica
2.
Am J Psychiatry ; 168(2): 152-62, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21078707

RESUMO

OBJECTIVE: Dysfunction in the amygdala and orbitofrontal cortex has been reported in youths and adults with psychopathic traits. The specific nature of the functional irregularities within these structures remains poorly understood. The authors used a passive avoidance task to examine the responsiveness of these systems to early stimulus-reinforcement exposure, when prediction errors are greatest and learning maximized, and to reward in youths with psychopathic traits and comparison youths. METHOD: While performing the passive avoidance learning task, 15 youths with conduct disorder or oppositional defiant disorder plus a high level of psychopathic traits and 15 healthy subjects completed a 3.0-T fMRI scan. RESULTS: Relative to the comparison youths, the youths with a disruptive behavior disorder plus psychopathic traits showed less orbitofrontal responsiveness both to early stimulus-reinforcement exposure and to rewards, as well as less caudate response to early stimulus-reinforcement exposure. There were no group differences in amygdala responsiveness to these two task measures, but amygdala responsiveness throughout the task was lower in the youths with psychopathic traits. CONCLUSIONS: Compromised sensitivity to early reinforcement information in the orbitofrontal cortex and caudate and to reward outcome information in the orbitofrontal cortex of youths with conduct disorder or oppositional defiant disorder plus psychopathic traits suggests that the integrated functioning of the amygdala, caudate, and orbitofrontal cortex may be disrupted. This provides a functional neural basis for why such youths are more likely to repeat disadvantageous decisions. New treatment possibilities are raised, as pharmacologic modulations of serotonin and dopamine can affect this form of learning.


Assuntos
Transtorno da Personalidade Antissocial/fisiopatologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/fisiopatologia , Núcleo Caudado/fisiopatologia , Transtorno da Conduta/fisiopatologia , Lobo Frontal/fisiopatologia , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Consumo de Oxigênio/fisiologia , Transdução de Sinais/fisiologia , Adolescente , Tonsila do Cerebelo/fisiopatologia , Transtorno da Personalidade Antissocial/diagnóstico , Transtorno da Personalidade Antissocial/psicologia , Aprendizagem por Associação/fisiologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/diagnóstico , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/psicologia , Aprendizagem da Esquiva/fisiologia , Mapeamento Encefálico , Transtorno da Conduta/diagnóstico , Transtorno da Conduta/psicologia , Tomada de Decisões/fisiologia , Retroalimentação Psicológica , Feminino , Humanos , Masculino , Motivação , Rede Nervosa/fisiopatologia , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Valores de Referência
3.
Arch Gen Psychiatry ; 65(5): 586-94, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18458210

RESUMO

CONTEXT: Children and adults with psychopathic traits and conduct or oppositional defiant disorder demonstrate poor decision making and are impaired in reversal learning. However, the neural basis of this impairment has not previously been investigated. Furthermore, despite high comorbidity of psychopathic traits and attention-deficit/hyperactivity disorder, to our knowledge, no research has attempted to distinguish neural correlates of childhood psychopathic traits and attention-deficit/hyperactivity disorder. OBJECTIVE: To determine the neural regions that underlie the reversal learning impairments in children with psychopathic traits plus conduct or oppositional defiant disorder. DESIGN: Case-control study. SETTING: Government clinical research institute. PARTICIPANTS: Forty-two adolescents aged 10 to 17 years: 14 with psychopathic traits and oppositional defiant disorder or conduct disorder, 14 with attention-deficit/hyperactivity disorder only, and 14 healthy controls. MAIN OUTCOME MEASURE: Blood oxygenation level-dependent signal as measured via functional magnetic resonance imaging during a probabilistic reversal task. RESULTS: Children with psychopathic traits showed abnormal responses within the ventromedial prefrontal cortex (Brodmann area 10) during punished reversal errors compared with children with attention-deficit/hyperactivity disorder and healthy children (P < .05 corrected for multiple comparisons). CONCLUSIONS: To our knowledge, this study provides the first evidence of abnormal ventromedial prefrontal cortex responsiveness in children with psychopathic traits and demonstrates this dysfunction was not attributable to comorbid attention-deficit/hyperactivity disorder. These findings suggest that reversal learning impairments in patients with developmental psychopathic traits relate to abnormal processing of reinforcement information.


Assuntos
Transtorno da Personalidade Antissocial/epidemiologia , Transtorno da Personalidade Antissocial/fisiopatologia , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Reversão de Aprendizagem , Núcleo Hipotalâmico Ventromedial/fisiopatologia , Adolescente , Transtorno da Personalidade Antissocial/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Índice de Gravidade de Doença
4.
Am J Psychiatry ; 165(6): 712-20, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18281412

RESUMO

OBJECTIVE: Extensive work implicates abnormal amygdala activation in emotional facial expression processing in adults with callous-unemotional traits. However, no research has examined amygdala response to emotional facial expressions in adolescents with disruptive behavior and callous-unemotional traits. Moreover, despite high comorbidity of callous-unemotional traits and attention deficit hyperactivity disorder (ADHD), no research has attempted to distinguish neural correlates of pediatric callous-unemotional traits and ADHD. METHOD: Participants were 36 children and adolescents (ages 10-17 years); 12 had callous-unemotional traits and either conduct disorder or oppositional defiant disorder, 12 had ADHD, and 12 were healthy comparison subjects. Functional MRI was used to assess amygdala activation patterns during processing of fearful facial expressions. Patterns in the callous-unemotional traits group were compared with those in the ADHD and comparison groups. RESULTS: In youths with callous-unemotional traits, amygdala activation was reduced relative to healthy comparison subjects and youths with ADHD while processing fearful expressions, but not neutral or angry expressions. Functional connectivity analyses demonstrated greater correlations between the amygdala and the ventromedial prefrontal cortex in comparison subjects and youths with ADHD relative to those with callous-unemotional traits. Symptom severity in the callous-unemotional traits groups was negatively correlated with connectivity between amygdala and ventromedial prefrontal cortex. CONCLUSIONS: This is the first study to demonstrate reduced amygdala responsiveness in youths with callous-unemotional traits. These findings support the contention that callous and unemotional personality traits are associated with reduced amygdala response to distress-based social cues.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/fisiopatologia , Empatia , Expressão Facial , Medo/fisiologia , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Reconhecimento Visual de Modelos/fisiologia , Adolescente , Ira/fisiologia , Nível de Alerta/fisiologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/diagnóstico , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/psicologia , Criança , Sinais (Psicologia) , Feminino , Humanos , Masculino , Vias Neurais/fisiologia , Oxigênio/sangue , Teoria da Construção Pessoal , Córtex Pré-Frontal/fisiopatologia , Valores de Referência
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