Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Hum Brain Mapp ; 40(14): 4026-4037, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31179609

RESUMO

Head motion is a common problem in clinical as well as empirical (functional) magnetic resonance imaging applications, as it can lead to severe artefacts that reduce image quality. The scanned individuals themselves, however, are often not aware of their head motion. The current study explored whether providing subjects with this information using tactile feedback would reduce their head motion and consequently improve image quality. In a single session that included six runs, 24 participants performed three different cognitive tasks: (a) passive viewing, (b) mental imagery, and (c) speeded responses. These tasks occurred in two different conditions: (a) with a strip of medical tape applied from one side of the magnetic resonance head coil, via the participant's forehead, to the other side, and (b) without the medical tape being applied. Results revealed that application of medical tape to the forehead of subjects to provide tactile feedback significantly reduced both translational as well as rotational head motion. While this effect did not differ between the three cognitive tasks, there was a negative quadratic relationship between head motion with and without feedback. That is, the more head motion a subject produced without feedback, the stronger the motion reduction given the feedback. In conclusion, the here tested method provides a simple and cost-efficient way to reduce subjects' head motion, and might be especially beneficial when extensive head motion is expected a priori.


Assuntos
Artefatos , Retroalimentação Sensorial , Movimentos da Cabeça , Imageamento por Ressonância Magnética/métodos , Adolescente , Feminino , Humanos , Masculino , Movimento (Física) , Tato , Adulto Jovem
2.
Child Psychiatry Hum Dev ; 44(6): 709-16, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23378186

RESUMO

The present research expands our understanding of cognitive and affective morality by exploring associations with callous-unemotional (CU) traits and externalizing symptoms. Participants were 46 8- to 12-year-old boys from the community who completed the Affective Morality Index, the Youth Self-Report, and the Inventory of Callous-Unemotional Traits. A pattern of results was found indicating that in particular the combination of high CU traits and high externalizing symptoms was associated with lack of affective morality, and an increased perceived likelihood of recommitting antisocial acts (recidivism). The implications of these findings and suggestions for future research are discussed.


Assuntos
Afeto/fisiologia , Transtorno da Personalidade Antissocial/fisiopatologia , Transtorno da Conduta/fisiopatologia , Julgamento/fisiologia , Princípios Morais , Bélgica , Criança , Humanos , Masculino
3.
J Nerv Ment Dis ; 197(3): 166-71, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19282682

RESUMO

The aim of this study was to examine whether self-esteem mediates the relationship between family factors and depressive symptoms in young adults. Participants completed self-report questionnaires about overall family environment, conflict with mother or father, parental rearing, self esteem, and depressive symptoms. Self-esteem was found to mediate the relationship between the combined family factors and depressive symptoms. When examined simultaneously, none of the individual family variables uniquely predicted depressive symptoms or self-esteem. However, separate analysis of each of the three family factors provided evidence for self-esteem mediating the relationship between parental conflict and depressive symptoms, and the relationship between parental care and depressive symptoms. Self-esteem may play a role in the mechanism underlying the link between parent-offspring relationship factors and depressive symptoms.


Assuntos
Depressão/psicologia , Conflito Familiar/psicologia , Autoimagem , Adulto , Depressão/diagnóstico , Feminino , Humanos , Masculino , Apego ao Objeto , Poder Familiar/psicologia , Inventário de Personalidade/estatística & dados numéricos , Projetos Piloto , Psicometria , Fatores de Risco , Meio Social , Estudantes/psicologia , Adulto Jovem
4.
Brain Behav ; 8(8): e01034, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29934977

RESUMO

BACKGROUND: Linking individual task performance to preceding, regional brain activation is an ongoing goal of neuroscientific research. Recently, it could be shown that the activation and connectivity within large-scale brain networks prior to task onset influence performance levels. More specifically, prestimulus default mode network (DMN) effects have been linked to performance levels in sensory near-threshold tasks, as well as cognitive tasks. However, it still remains uncertain how the DMN state preceding cognitive tasks affects performance levels when the period between task trials is long and flexible, allowing participants to engage in different cognitive states. METHODS: We here investigated whether the prestimulus activation and within-network connectivity of the DMN are predictive of the correctness and speed of task performance levels on a cognitive (match-to-sample) mental rotation task, employing a sparse event-related functional magnetic resonance imaging (fMRI) design. RESULTS: We found that prestimulus activation in the DMN predicted the speed of correct trials, with a lower amplitude preceding correct fast response trials compared to correct slow response trials. Moreover, we found higher connectivity within the DMN before incorrect trials compared to correct trials. CONCLUSION: These results indicate that pre-existing activation and connectivity states within the DMN influence task performance on cognitive tasks, both effecting the correctness and speed of task execution. The findings support existing theories and empirical work on relating mind-wandering and cognitive task performance to the DMN and expand these by establishing a relationship between the prestimulus DMN state and the speed of cognitive task performance.


Assuntos
Encéfalo/fisiologia , Cognição/fisiologia , Imageamento por Ressonância Magnética/métodos , Estimulação Luminosa/métodos , Análise e Desempenho de Tarefas , Percepção Visual/fisiologia , Adulto , Mapeamento Encefálico/métodos , Feminino , Humanos , Masculino , Valores de Referência
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA