RESUMO
INTRODUCTION: Low birth weight is associated with obesity and an increased risk for metabolic/cardiovascular diseases in later life. RESULTS: The results of the snack delay test, which encompassed four distinct trials, indicated that the gender × intrauterine growth restriction (IUGR) × trial interaction was a predictor of the ability to delay the food reward (P = 0.002). Among children with normal birth weights, girls showed a greater ability to delay food rewards than did boys (P = 0.014).In contrast, among children with IUGR, there was no such differential ability between girls and boys. Furthermore, in girls, impulsive responding predicted both increased consumption of palatable fat (P = 0.007) and higher BMIs (P = 0.020) at 48 mo of age, although there was no such association with BMI at 36 mo. DISCUSSION: In girls, the quality of fetal growth may contribute to impulsive eating, which may promote an increased intake of fats and consequently higher BMIs. As with the original thrifty phenotype, such a mechanism would be adaptive when food supplies are sparse, but would be problematic in societies with ample access to calorically rich foods. METHODS: We examined whether the quality of intrauterine growth programs obesogenic eating behaviors, by investigating (i) the relationship between birth weight and impulsive eating in 3-year-old children (using the snack delay test), and (ii) whether impulsive eating predicts fat intake and/or BMI at 4 years of age (using a laboratory-based test meal).
Assuntos
Peso ao Nascer/fisiologia , Comportamento Alimentar/fisiologia , Retardo do Crescimento Fetal/fisiopatologia , Comportamento Impulsivo/fisiopatologia , Fenótipo , Envelhecimento/fisiologia , Índice de Massa Corporal , Pré-Escolar , Estudos de Coortes , Gorduras na Dieta , Ingestão de Alimentos/fisiologia , Feminino , Seguimentos , Humanos , Masculino , Obesidade/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Caracteres SexuaisRESUMO
INTRODUCTION: N200 (N2) is an electrophysiological component related with the analysis of perceptual disruptions and with the recognition of a stop signal (inhibitory control); neuroanatomically, it has been associated with right-hand orbitofrontal structures. Its modulation has been studied with go/no go-type tasks and the Stop Signal Task (SST). DEVELOPMENT: While the SST is being carried out in subjects with attention deficit hyperactivity disorder (ADHD), differences in the amplitude of the N2 have been observed in comparison to control subjects. Moreover, a number of studies have reported that ADHD has a high degree of inheritability, with linkages to several susceptibility loci. From all this, it is acknowledged that inhibitory control, and more particularly N2 modulation, is a quantitative trait that may be expressed in different ways in the members of families with and without ADHD, as well as in unaffected subjects from the general population, while also being a candidate as an endophenotype of the disorder. This hypothesis has been confirmed in 141 families with the genetic isolate of Antioquia, in which differences have been identified in this electrical signal on comparing the members of affected and unaffected families and these two groups with unaffected members of the general population. CONCLUSIONS: These findings suggest that N2 is an electrophysiological signal that is modulated by faulty inhibitory control in subjects with ADHD and, in this respect, could be used as a candidate in the search for endophenotypes in the familial form of this disorder.
Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Eletroencefalografia , Fenômenos Eletrofisiológicos/fisiologia , Endofenótipos , Comportamento Impulsivo/fisiopatologia , Inibição Psicológica , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Humanos , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologiaRESUMO
OBJECTIVE: Cannabis is the most used illicit drug worldwide, however only a few studies have examined cognitive deficits related to its use. Clinical manifestations associated with those deficits include a motivational syndrome, impairment in cognitive flexibility, inattention, deficits in abstract reasoning and concept formation, aspects intimately related to the executive functions, which potentially exert a central role in substance dependence. The objective was to make a review about consequences of cannabis use in executive functioning. METHOD: This review was carried out on reports drawn from MedLine, SciELO, and Lilacs. DISCUSSION: In studies investigating acute use effects, higher doses of tetrahydrocannabinol are associated to impairments in performance of nonsevere users in planning and control impulse tasks. However, chronic cannabis users do not show those impairments. Although demonstration of residual effects of cannabis in the executive functioning is controversial, persistent deficits seem to be present at least in a subgroup of chronic users after 28 days of abstinence. CONCLUSIONS: The neuropsychological studies found did not have as a main aim the evaluation of executive functioning. A criterial selection of standardized neuropsychological tests, more appropriate study designs as well as concomitant investigations with structural and functional neuroimaging techniques may improve the understanding of eventual neurotoxicity associated with cannabis use.
Assuntos
Canabinoides/farmacologia , Transtornos Cognitivos/induzido quimicamente , Cognição/efeitos dos fármacos , Abuso de Maconha/psicologia , Fumar Maconha/efeitos adversos , Atenção/efeitos dos fármacos , Transtornos Cognitivos/fisiopatologia , Formação de Conceito/efeitos dos fármacos , Tomada de Decisões , Dronabinol/toxicidade , Lobo Frontal/efeitos dos fármacos , Humanos , Comportamento Impulsivo/induzido quimicamente , Comportamento Impulsivo/fisiopatologia , Comportamento Impulsivo/psicologia , Fumar Maconha/fisiopatologia , Fumar Maconha/psicologia , Testes NeuropsicológicosRESUMO
OBJETIVO: A maconha é a droga ilícita mais consumida no mundo, porém ainda existem poucos estudos examinando eventuais prejuízos cognitivos relacionados ao seu uso. As manifestações clínicas associadas a esses déficits incluem síndrome amotivacional, prejuízo na flexibilidade cognitiva, desatenção, dificuldade de raciocínio abstrato e formação de conceitos, aspectos intimamente ligados às funções executivas, as quais potencialmente exercem um papel central na dependência de substâncias. O objetivo do estudo foi fazer uma revisão a respeito das implicações do uso da maconha no funcionamento executivo. MÉTODO: Esta revisão foi conduzida utilizando-se bases de dados eletrônicas (MedLine, Pubmed, SciELO and Lilacs). DISCUSSÃO: Em estudos de efeito agudo, doses maiores de tetrahidrocanabinol encontram-se associadas a maior prejuízo no desempenho de usuários leves em tarefas de controle inibitório e planejamento; porém, este efeito dose-resposta não ocorre em usuários crônicos. Embora haja controvérsias no que se refere a efeitos residuais da maconha, déficits persistentes parecem estar presentes após 28 dias de abstinência, ao menos em um subgrupo de usuários crônicos. CONCLUSÕES: Os estudos encontrados não tiveram como objetivo principal a avaliação das funções executivas. A seleção de testes padronizados, desenhos de estudos mais apropriados e o uso concomitante com técnicas de neuroimagem estrutural e funcional podem auxiliar na melhor compreensão das conseqüências deletérias do uso crônico da maconha no funcionamento executivo.
OBJECTIVE: Cannabis is the most used illicit drug worldwide, however only a few studies have examined cognitive deficits related to its use. Clinical manifestations associated with those deficits include amotivational syndrome, impairment in cognitive flexibility, inattention, deficits in abstract reasoning and concept formation, aspects intimately related to the executive functions, which potentially exert a central role in substance dependence. The objective was to make a review about consequences of cannabis use in executive functioning. METHOD: This review was carried out on reports drawn from MedLine, SciELO, and Lilacs. DISCUSSION: In studies investigating acute use effects, higher doses of tetrahydrocannabinol are associated to impairments in performance of nonsevere users in planning and control impulse tasks. However, chronic cannabis users do not show those impairments. Although demonstration of residual effects of cannabis in the executive functioning is controversial, persistent deficits seem to be present at least in a subgroup of chronic users after 28 days of abstinence. CONCLUSIONS: The neuropsychological studies found did not have as a main aim the evaluation of executive functioning. A criterial selection of standardized neuropsychological tests, more appropriate study designs as well as concomitant investigations with structural and functional neuroimaging techniques may improve the understanding of eventual neurotoxicity associated with cannabis use.
Assuntos
Humanos , Canabinoides/farmacologia , Transtornos Cognitivos/induzido quimicamente , Cognição/efeitos dos fármacos , Abuso de Maconha/psicologia , Fumar Maconha/efeitos adversos , Atenção/efeitos dos fármacos , Transtornos Cognitivos/fisiopatologia , Formação de Conceito/efeitos dos fármacos , Tomada de Decisões , Lobo Frontal/efeitos dos fármacos , Comportamento Impulsivo/induzido quimicamente , Comportamento Impulsivo/fisiopatologia , Comportamento Impulsivo/psicologia , Fumar Maconha/fisiopatologia , Fumar Maconha/psicologia , Testes Neuropsicológicos , Dronabinol/toxicidadeRESUMO
Prefrontal cortex (PFC) dysfunction can lead to impairment in planning and behavioral inhibition, as well as personality changes. As ascending monoaminergic brainstem systems modulate PFC functioning, it is possible that lesions in the brainstem lead to symptoms similar to prefrontal dysfunction. A 29-year-old man developed several cognitive and behavioral symptoms after neurosurgery for resection of a pilocytic astrocytoma in the pontine-mesencephalic area. A careful analysis of symptoms indicated PFC dysfunction that could be attributed to lesions in the ascending monoaminergic brainstem systems. Interestingly, the cognitive symptoms improved after treatment with methylphenidate, which is a drug that modules catecholaminergic neurotransmission, thereby supporting this hypothesis. This is a unique case of PFC dysfunction that may be related to post-operative lesion of the catecholaminergic nuclei in the brainstem.
Assuntos
Astrocitoma/cirurgia , Neoplasias do Tronco Encefálico/cirurgia , Transtornos Cognitivos/fisiopatologia , Complicações Pós-Operatórias/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Adolescente , Adulto , Astrocitoma/diagnóstico , Atenção/efeitos dos fármacos , Atenção/fisiologia , Neoplasias do Tronco Encefálico/diagnóstico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/tratamento farmacológico , Escolaridade , Seguimentos , Humanos , Comportamento Impulsivo/diagnóstico , Comportamento Impulsivo/tratamento farmacológico , Comportamento Impulsivo/fisiopatologia , Inibição Psicológica , Relações Interpessoais , Deficiências da Aprendizagem/diagnóstico , Deficiências da Aprendizagem/tratamento farmacológico , Deficiências da Aprendizagem/fisiopatologia , Masculino , Metilfenidato/uso terapêutico , Testes Neuropsicológicos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/tratamento farmacológico , Resolução de Problemas/efeitos dos fármacos , Resolução de Problemas/fisiologiaRESUMO
Sydenham's chorea (SC) is a disorder of the central nervous system (CNS) characterized by sudden, involuntary, arrhythmic, clonic, and purposeless movements. SC appears to provide a model for understanding various neuropsychiatric dysfunctions. Its relationship with attentional deficits, obsessive-compulsive symptoms (OCS) as well as movement disorders provides support for the hypothesis of the involvement of the corticostriatal loops in the pathophysiology of the disorder.