Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Behav Brain Sci ; 47: e92, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38770864

RESUMO

By examining the shared neuro-cognitive correlates of curiosity and creativity, we better understand the brain basis of creativity. However, by only examining shared components, important neuro-cognitive correlates are overlooked. Here, we argue that any comprehensive brain model of creativity should consider multiple cognitive processes and, alongside the interplay between brain networks, also the neurochemistry and neural oscillations that underly creativity.


Assuntos
Encéfalo , Cognição , Criatividade , Humanos , Encéfalo/fisiologia , Cognição/fisiologia , Comportamento Exploratório/fisiologia , Rede Nervosa/fisiologia , Vias Neurais/fisiologia
2.
Infant Child Dev ; 27(2): e2067, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29780286

RESUMO

For parents, online platforms where their children interact with others often feel like a "black box" in terms of what exactly is happening. In this study, we developed an ecologically valid online computer game in which a (computer-generated) peer teammate tried to provoke frustration, in order to examine (a) adolescents' responses and (b) how indices of self-evaluation (i.e., sense of coherence and self-esteem) and demographic variables (i.e., gender and ethnicity) matter to these responses. Like gender, being a member of a minority or majority group may influence how provocations by peers are interpreted, influencing how one responds. Fifteen-year-old Dutch and Moroccan-Dutch adolescents (N = 167) completed self-reports and played the online computer game. The game indeed elicited frustration, with increased self-reported anger. Moreover, expressions of displeasure were much more common during and after provocation than before provocation. Crucially, perceived self-evaluation mattered; higher levels of sense of coherence but lower levels of self-esteem (only in Moroccan-Dutch group) contributed to fewer expressions of displeasure. Gender did not play a moderating role. Our findings provide initial insights into individual differences in adolescents' responses in an online peer-conflict situation. HIGHLIGHTS: We studied Dutch and Moroccan-Dutch adolescents' responses during online peer provocation and how self-evaluation and demographic variables matter.Provocation by the (computer-generated) peer teammate increased expressions of displeasure.More sense of coherence but less self-esteem was associated with fewer expressions of displeasure, but ethnicity moderated the effect with self-esteem.

3.
Neuroimage ; 120: 75-87, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26169324

RESUMO

Large-scale networks support the dynamic integration of information across multiple functionally specialized brain regions. Network analyses of haemodynamic modulations have revealed such functional brain networks that show high consistency across subjects and different cognitive states. However, the relationship between the slowly fluctuating haemodynamic responses and the underlying neural mechanisms is not well understood. Resting state studies have revealed spatial similarities in the estimated network hub locations derived using haemodynamic and electrophysiological recordings, suggesting a direct neural basis for the widely described functional magnetic resonance imaging (fMRI) resting state networks. To truly understand the nature of the relationship between electrophysiology and haemodynamics it is important to move away from a task absent state and to establish if such networks are differentially modulated by cognitive processing. The present parallel fMRI and magnetoencephalography (MEG) experiment investigated the structural similarities between haemodynamic networks and their electrophysiological counterparts when either the stimulus or the task was varied. Connectivity patterns underlying action vs. object naming (task-driven modulations), and action vs. object images (stimulus-driven modulations) were identified in a data driven all-to-all connectivity analysis, with cross spectral coherence adopted as a metric of functional connectivity in both MEG and fMRI. We observed a striking difference in functional connectivity between conditions. The spectral profiles of the frequency-specific network similarity differed significantly for the task-driven vs. stimulus-driven connectivity modulations. While the greatest similarity between MEG and fMRI derived networks was observed at neural frequencies below 30 Hz, haemodynamic network interactions could not be attributed to a single frequency band. Instead, the entire spectral profile should be taken into account when assessing the correspondence between MEG and fMRI networks. Task-driven network hubs, evident in both MEG and fMRI, were found in cortical regions previously associated with language processing, including the posterior temporal cortex and the inferior frontal cortex. Network hubs related to stimulus-driven modulations, however, were found in regions related to object recognition and visual processing, including the lateral occipital cortex. Overall, the results depict a shift in network structure when moving from a task dependent modulation to a stimulus dependent modulation, revealing a reorganization of large-scale functional connectivity during task performance.


Assuntos
Córtex Cerebral/fisiologia , Conectoma/métodos , Fenômenos Eletrofisiológicos/fisiologia , Rede Nervosa/fisiologia , Acoplamento Neurovascular/fisiologia , Desempenho Psicomotor/fisiologia , Comportamento Verbal/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Magnetoencefalografia/métodos , Masculino , Adulto Jovem
4.
Hum Brain Mapp ; 36(3): 1202-16, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25413681

RESUMO

Language production is a complex neural process that requires the interplay between multiple specialized cortical regions. We investigated modulations in large-scale cortical networks underlying preparation for speech production by contrasting cortico-cortical coherence for overt and silent picture naming in an all-to-all connectivity analysis. To capture transient, frequency-specific changes in functional connectivity we analyzed the magnetoencephalography data in two consecutive 300-ms time windows. Within the first 300 ms following picture onset beta frequency coherence was increased for overt naming in a network of regions comprising the bilateral parieto-temporal junction and medial cortices, suggesting that overt articulation modifies selection processes involved in speech planning. In the late time window (300-600 ms after picture onset) beta-range coherence was enhanced in a network that included the ventral sensorimotor and temporal cortices. Coherence in the gamma band was simultaneously reduced between the ventral motor cortex and supplementary motor area, bilaterally. The results suggest functionally distinct roles for beta (facilitatory) and gamma (suppressive) band interactions in speech production, with strong involvement of the motor cortex in both frequency bands. Overall, a striking difference in functional connectivity between the early and late time windows was observed, revealing the dynamic nature of large-scale cortical networks that support language and speech. Our results demonstrate that as the naming task evolves in time, the global connectivity patterns change, and that these changes occur (at least) on the time-scale of a few hundred milliseconds. More generally, these results bear implications for how we view large-scale neural networks underlying task performance.


Assuntos
Ondas Encefálicas/fisiologia , Córtex Cerebral/fisiologia , Conectoma , Magnetoencefalografia/métodos , Fala/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Fatores de Tempo , Adulto Jovem
5.
Hum Brain Mapp ; 36(7): 2455-69, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25760689

RESUMO

Electrophysiological oscillatory coherence between brain regions has been proposed to facilitate functional long-range connectivity within neurocognitive networks. This notion is supported by intracortical recordings of coherence in singled-out corticocortical connections in the primate cortex. However, the manner in which this operational principle manifests in the task-sensitive connectivity that supports human naturalistic performance remains undercharacterized. Here, we demonstrate task-sensitive reconfiguration of global patterns of coherent connectivity in association with a set of easier and more demanding naturalistic tasks, ranging from picture comparison to speech comprehension and object manipulation. Based on whole-cortex neuromagnetic recording in healthy behaving individuals, the task-sensitive component of long-range corticocortical coherence was mapped at spectrally narrow-band oscillatory frequencies between 6 and 20 Hz (theta to alpha and low-beta bands). This data-driven cortical mapping unveiled markedly distinct and topologically task-relevant spatiospectral connectivity patterns for the different tasks. The results demonstrate semistable oscillatory states relevant for neurocognitive processing. The present findings decisively link human behavior to corticocortical coherence at oscillatory frequencies that are widely thought to convey long-range, feedback-type neural interaction in cortical functional networks.


Assuntos
Mapeamento Encefálico/métodos , Ondas Encefálicas/fisiologia , Córtex Cerebral/fisiologia , Sincronização Cortical/fisiologia , Magnetoencefalografia/métodos , Rede Nervosa/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
6.
Neuroimage ; 94: 89-95, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24636880

RESUMO

There are now a number of non-invasive methods to image human brain function in-vivo. However, the accuracy of these images remains unknown and can currently only be estimated through the use of invasive recordings to generate a functional ground truth. Neuronal activity follows grey matter structure and accurate estimates of neuronal activity will have stronger support from accurate generative models of anatomy. Here we introduce a general framework that, for the first time, enables the spatial distortion of a functional brain image to be estimated empirically. We use a spherical harmonic decomposition to modulate each cortical hemisphere from its original form towards progressively simpler structures, ending in an ellipsoid. Functional estimates that are not supported by the simpler cortical structures have less inherent spatial distortion. This method allows us to compare directly between magnetoencephalography (MEG) source reconstructions based upon different assumption sets without recourse to functional ground truth.


Assuntos
Algoritmos , Mapeamento Encefálico/métodos , Substância Cinzenta/anatomia & histologia , Substância Cinzenta/fisiologia , Magnetoencefalografia/métodos , Modelos Anatômicos , Modelos Neurológicos , Simulação por Computador , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Annu Rev Biomed Eng ; 14: 295-323, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22809139

RESUMO

Achieving control over cell behavior and pattern formation requires molecular-level understanding of regulatory mechanisms. Alongside transcriptional networks and biochemical gradients, there functions an important system of cellular communication and control: transmembrane voltage gradients (V(mem)). Bioelectrical signals encoded in spatiotemporal changes of V(mem) control cell proliferation, migration, and differentiation. Moreover, endogenous bioelectrical gradients serve as instructive cues mediating anatomical polarity and other organ-level aspects of morphogenesis. In the past decade, significant advances in molecular physiology have enabled the development of new genetic and biophysical tools for the investigation and functional manipulation of bioelectric cues. Recent data implicate V(mem) as a crucial epigenetic regulator of patterning events in embryogenesis, regeneration, and cancer. We review new conceptual and methodological developments in this fascinating field. Bioelectricity offers a novel way of quantitatively understanding regulation of growth and form in vivo, and it reveals tractable, powerful control points that will enable truly transformative applications in bioengineering, regenerative medicine, and synthetic biology.


Assuntos
Engenharia Biomédica/métodos , Engenharia Biomédica/tendências , Animais , Fontes de Energia Bioelétrica , Comunicação Celular , Diferenciação Celular , Movimento Celular , Proliferação de Células , Impedância Elétrica , Epigênese Genética , Junções Comunicantes/fisiologia , Humanos , Neoplasias/terapia , Regeneração/fisiologia , Engenharia Tecidual/métodos
8.
J Exp Psychol Learn Mem Cogn ; 49(6): 849-865, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36326653

RESUMO

When producing creative ideas (i.e., ideas that are original and useful) two main processes occur: ideation, where people brainstorm ideas, and evaluation, where they decide if the ideas are creative or not. While much is known about the ideation phase, the cognitive processes involved in creativity evaluation are less clear. In this article, we present a novel modeling approach for the evaluation phase of creativity. We apply the drift diffusion model (DDM) to the Creative-or-Not task (CON-task) to study the cognitive basis of evaluation and to examine individual differences in the extent to which people take originality and utility into account when evaluating creative ideas. The CON-task is a timed decision-making task where participants indicate whether they find uses for certain objects creative or not (e.g., using a book as a buoy). The different uses vary on the two creativity dimensions "originality" and "utility." In two studies (n = 293, 17,806 trials; n = 152, 9,291 trials), we found that stimulus originality was strongly related to participants' drift rates but found only weak evidence for an association between stimulus utility and the drift rate. However, participants differed substantially in the effects of originality and utility. Furthermore, the implicit weights assigned to originality and utility on the CON-task were associated with self-reported importance ratings of originality and utility and with divergent thinking performance in the Alternative Uses task (AUT). This research provides a cognitive modeling approach to creativity evaluation and underlines the importance of communicating rating criteria in divergent thinking tasks to ensure a fair assessment of creative ability. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Criatividade , Individualidade , Humanos
9.
Neuroimage ; 55(4): 1804-15, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21044687

RESUMO

In this study, we elucidate the changes in neural oscillatory processes that are induced by simple working memory tasks. A group of eight subjects took part in modified versions of the N-back and Sternberg working memory paradigms. Magnetoencephalography (MEG) data were recorded, and subsequently processed using beamformer based source imaging methodology. Our study shows statistically significant increases in θ oscillations during both N-back and Sternberg tasks. These oscillations were shown to originate in the medial frontal cortex, and further to scale with memory load. We have also shown that increases in θ oscillations are accompanied by decreases in ß and γ band oscillations at the same spatial coordinate. These decreases were most prominent in the 20-40 Hz frequency range, although spectral analysis showed that γ band power decrease extends up to at least 80 Hz. ß/γ Power decrease also scales with memory load. Whilst θ increases were predominately observed in the medial frontal cortex, ß/γ decreases were associated with other brain areas, including nodes of the default mode network (for the N-back task) and areas associated with language processing (for the Sternberg task). These observations are in agreement with intracranial EEG and fMRI studies. Finally, we have shown an intimate relationship between changes in ß/γ band oscillatory power at spatially separate network nodes, implying that activity in these nodes is not reflective of uni-modal task driven changes in spatially separate brain regions, but rather represents correlated network activity. The utility of MEG as a non-invasive means to measure neural oscillatory modulation has been demonstrated and future studies employing this technology have the potential to gain a better understanding of neural oscillatory processes, their relationship to functional and effective connectivity, and their correspondence to BOLD fMRI.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Magnetoencefalografia/métodos , Memória de Curto Prazo/fisiologia , Rede Nervosa/fisiologia , Plasticidade Neuronal/fisiologia , Adaptação Fisiológica/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
10.
Neuroimage ; 56(3): 1082-104, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21352925

RESUMO

Functional connectivity (FC) between brain regions is thought to be central to the way in which the brain processes information. Abnormal connectivity is thought to be implicated in a number of diseases. The ability to study FC is therefore a key goal for neuroimaging. Functional connectivity (fc) MRI has become a popular tool to make connectivity measurements but the technique is limited by its indirect nature. A multimodal approach is therefore an attractive means to investigate the electrodynamic mechanisms underlying hemodynamic connectivity. In this paper, we investigate resting state FC using fcMRI and magnetoencephalography (MEG). In fcMRI, we exploit the advantages afforded by ultra high magnetic field. In MEG we apply envelope correlation and coherence techniques to source space projected MEG signals. We show that beamforming provides an excellent means to measure FC in source space using MEG data. However, care must be taken when interpreting these measurements since cross talk between voxels in source space can potentially lead to spurious connectivity and this must be taken into account in all studies of this type. We show good spatial agreement between FC measured independently using MEG and fcMRI; FC between sensorimotor cortices was observed using both modalities, with the best spatial agreement when MEG data are filtered into the ß band. This finding helps to reduce the potential confounds associated with each modality alone: while it helps reduce the uncertainties in spatial patterns generated by MEG (brought about by the ill posed inverse problem), addition of electrodynamic metric confirms the neural basis of fcMRI measurements. Finally, we show that multiple MEG based FC metrics allow the potential to move beyond what is possible using fcMRI, and investigate the nature of electrodynamic connectivity. Our results extend those from previous studies and add weight to the argument that neural oscillations are intimately related to functional connectivity and the BOLD response.


Assuntos
Imageamento por Ressonância Magnética/métodos , Magnetoencefalografia/métodos , Vias Neurais/anatomia & histologia , Algoritmos , Encéfalo/anatomia & histologia , Mapeamento Encefálico/métodos , Circulação Cerebrovascular/fisiologia , Interpretação Estatística de Dados , Vias Eferentes/anatomia & histologia , Vias Eferentes/fisiologia , Campos Eletromagnéticos , Fenômenos Eletrofisiológicos , Dedos/inervação , Dedos/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Córtex Motor/anatomia & histologia , Córtex Motor/fisiologia , Movimento/fisiologia , Oxigênio/sangue
11.
Hum Brain Mapp ; 32(2): 182-97, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21229612

RESUMO

Oscillatory activity in the ß-band (15-30 Hz) has been studied in detail in the sensorimotor cortex. It has been postulated that ß-activity acts as a localized gating of cortical activity. Here, the induced oscillatory response in the ß-band is measured by magnetoencephalography, and the hemodynamic response is measured by fMRI. We assess the linearity of the responses to stimuli of varying duration in the primary motor cortex and to a sinusoidal drifting grating of varying contrast amplitude and drift frequency in the visual cortex. In this way, we explore the nature of ß-oscillations and their relationship with hemodynamic effects. Excellent spatial colocalization of BOLD and ß-activity in both central and lateral (MT) visual areas and sensorimotor areas suggests that the two are intimately related. In contrast to the BOLD response, the level of ß-desynchronization is not modulated by stimulus contrast or by stimulus duration, consistent with a gating role. The amplitude of ß-desynchronization in the central visual area is however modulated by drift frequency, and this seems to parallel the modulation in BOLD amplitude at the same location.


Assuntos
Ritmo beta/fisiologia , Mapeamento Encefálico , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/fisiologia , Imageamento por Ressonância Magnética , Estatística como Assunto , Adulto , Biofísica , Sensibilidades de Contraste/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Magnetoencefalografia , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Oxigênio/sangue , Estimulação Luminosa/métodos , Fatores de Tempo , Adulto Jovem
12.
J Intell ; 9(1)2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33669216

RESUMO

Despite decades of extensive research on creativity, the field still combats psychometric problems when measuring individual differences in creative ability and people's potential to achieve real-world outcomes that are both original and useful. We think these seemingly technical issues have a conceptual origin. We therefore propose a minimal theory of creative ability (MTCA) to create a consistent conceptual theory to guide investigations of individual differences in creative ability. Building on robust theories and findings in creativity and individual differences research, our theory argues that creative ability, at a minimum, must include two facets: intelligence and expertise. So, the MTCA simply claims that whenever we do something creative, we use most of our cognitive abilities combined with relevant expertise to be creative. MTCA has important implications for creativity theory, measurement, and practice. However, the MTCA isn't necessarily true; it is a minimal theory. We discuss and reject several objections to the MTCA.

13.
Neuroimage ; 49(2): 1479-89, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19778617

RESUMO

The exact relationship between neural activity and BOLD fMRI is unknown. However, several recent findings, recorded invasively in both humans and monkeys, show a positive correlation of BOLD to high-frequency (30-150 Hz) oscillatory power changes and a negative correlation to low-frequency (8-30 Hz) power changes arising from cortical areas. In this study, we computed the time series correlation between BOLD GE-EPI fMRI at 7 T and neural activity measures from noninvasive MEG, using a time-frequency beam former for source localisation. A sinusoidal drifting grating was presented visually for 4 s followed by a 20 s rest period in both recording modalities. The MEG time series were convolved with either a measured or canonical haemodynamic response function (HRF) for comparison with the measured BOLD data, and the BOLD data were deconvolved with either a measured or a canonical HRF for comparison with the measured MEG. In the visual cortex, the higher frequencies (mid-gamma=52-75 Hz and high-gamma=75-98 Hz) were positively correlated with BOLD whilst the lower frequencies (alpha=8-12 Hz and beta=12-25 Hz) were negatively correlated with BOLD. Furthermore, regression including all frequency bands predicted BOLD better than stimulus timing alone, although no individual frequency band predicted BOLD as well as stimulus timing. For this paradigm, there was, in general, no difference between using the SPM canonical HRF compared to the subject-specific measured HRF. In conclusion, MEG replicates findings from invasive recordings with regard to time series correlations with BOLD data. Conversely, deconvolution of BOLD data provides a neural estimate which correlates well with measured neural effects as a function of neural oscillation frequency.


Assuntos
Modelos Lineares , Imageamento por Ressonância Magnética/métodos , Magnetoencefalografia/métodos , Oxigênio/sangue , Periodicidade , Córtex Visual/fisiologia , Humanos , Estimulação Luminosa , Análise de Regressão , Processamento de Sinais Assistido por Computador , Fatores de Tempo , Córtex Visual/irrigação sanguínea , Percepção Visual/fisiologia
14.
Neuroimage ; 49(1): 525-38, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19635575

RESUMO

This study shows that the spatial specificity of MEG beamformer estimates of electrical activity can be affected significantly by the way in which covariance estimates are calculated. We define spatial specificity as the ability to extract independent timecourse estimates of electrical brain activity from two separate brain locations in close proximity. Previous analytical and simulated results have shown that beamformer estimates are affected by narrowing the time frequency window in which covariance estimates are made. Here we build on this by both experimental validation of previous results, and investigating the effect of data averaging prior to covariance estimation. In appropriate circumstances, we show that averaging has a marked effect on spatial specificity. However the averaging process results in ill-conditioned covariance matrices, thus necessitating a suitable matrix regularisation strategy, an example of which is described. We apply our findings to an MEG retinotopic mapping paradigm. A moving visual stimulus is used to elicit brain activation at different retinotopic locations in the visual cortex. This gives the impression of a moving electrical dipolar source in the brain. We show that if appropriate beamformer optimisation is applied, the moving source can be tracked in the cortex. In addition to spatial reconstruction of the moving source, we show that timecourse estimates can be extracted from neighbouring locations of interest in the visual cortex. If appropriate methodology is employed, the sequential activation of separate retinotopic locations can be observed. The retinotopic paradigm represents an ideal platform to test the spatial specificity of source localisation strategies. We suggest that future comparisons of MEG source localisation techniques (e.g. beamformer, minimum norm, Bayesian) could be made using this retinotopic mapping paradigm.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Magnetoencefalografia/estatística & dados numéricos , Algoritmos , Simulação por Computador , Eletrofisiologia , Humanos , Distribuição Normal , Estimulação Luminosa , Retina/fisiologia , Córtex Visual/anatomia & histologia , Campos Visuais/fisiologia
15.
MAGMA ; 23(5-6): 339-49, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20625794

RESUMO

OBJECT: The objective of this work was to assess functional connectivity measurements at ultra-high field (7T), given BOLD contrast to noise ratio increases with magnetic field strength but physiological noise also increases. MATERIALS AND METHODS: Resting state BOLD data were acquired at 3 and 7T to assess connectivity in the sensorimotor network (SMN) and default mode network (DMN) at different spatial smoothing levels. RESULTS: At 3 and 7T positive correlation is observed between a right sensorimotor seed and left sensorimotor cortex. For the DMN, a seed in posterior cingulate cortex results in a high correlation in inferior parietal lobes and medial prefrontal cortex. We show higher temporal correlation coefficients for both the SMN and DMN at 7T compared to 3T for all smoothing levels. A spatial correlation between connectivity maps revealed no significant differences for the SMN, whilst the DMN showed increased spatial correlation dependent on SNR. The maximum physiological noise contribution was found to be higher at 7T, but noise in both seed and network nodes was not significantly increased, as shown by no significant difference in the spatial correlation of maps following physiological correction. CONCLUSION: 7T can improve spatial specificity of connectivity maps and facilitate measurement of connectivity in areas of lower intrinsic network correlation.


Assuntos
Imageamento por Ressonância Magnética/métodos , Vias Neurais/fisiopatologia , Desempenho Psicomotor/fisiologia , Córtex Cerebral/fisiopatologia , Giro do Cíngulo/fisiopatologia , Humanos , Limiar Sensorial/fisiologia
16.
J Forensic Nurs ; 16(3): 169-178, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32195758

RESUMO

BACKGROUND: The therapeutic relationship is synonymous with mental health nursing and fundamental to the provision of nursing care, regardless of the setting in which care is provided. This literature review examines, from a nursing perspective, factors influencing the formation and maintenance of therapeutic relationships in forensic mental health settings. METHODS: A systematic search of the literature, using a range of electronic databases, focusing on nurse-patient therapeutic relationships in forensic settings was conducted. Articles were Critical Appraisal Skills Programme quality appraised, followed by a meta-aggregative thematic approach to data analysis and synthesis to identify themes and, finally, a production of an "action" policy statement. FINDINGS AND IMPLICATION FOR PRACTICE: Eight articles met the criteria for review inclusion. Nine themes were identified; seven were categorized as internal/interpersonal factors, and two were categorized as external/environmental factors (with some themes interconnected). Synthesis of findings resulted in the production of a policy statement encouraging forensic mental health nurses to be aware of intrapersonal influences on therapeutic relationships and the need to provide a safe and supportive clinical environment for these relationships to form.


Assuntos
Relações Enfermeiro-Paciente , Enfermagem Psiquiátrica , Atitude do Pessoal de Saúde , Transtorno da Personalidade Borderline/psicologia , Comunicação , Empatia , Medo , Hospitais Psiquiátricos , Humanos , Relações Interprofissionais , Resiliência Psicológica , Medidas de Segurança , Confiança , Violência no Trabalho/psicologia
17.
Neuroimage ; 45(2): 440-52, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19049883

RESUMO

This paper investigates the application of source reconstruction methodologies to EEG data recorded in concurrent EEG/fMRI experiments at 7T. An EEG phantom containing a dipolar current source is described and used to investigate the accuracy of source localisation. Both dipole fitting and beamformer algorithms are shown to yield accurate locations for the dipole within the phantom. Source reconstruction methodologies are also shown to reduce significantly the level of interference in the recorded EEG, caused by the MR scanner. A comparison between beamformer and dipole fitting approaches is made and it is shown that, due to its adaptive weighting parameters, the beamformer provides better suppression of interference when compared to the dipole fit. In addition it is shown that, in the case of the beamformer, use of a high EEG channel density improves the level of interference reduction, and the ratio of measured signal to interference can be improved by a factor of approximately 1.6 if the number of EEG electrodes is increased from 32 to 64. The interference reduction properties of source localisation are shown theoretically, in simulation, and in phantom data. Finally, in-vivo experiments conducted at 7T show that effects in the gamma band can be recorded using simultaneous EEG/fMRI. These results are achieved by application of beamformer methodology to 64 channel EEG data.


Assuntos
Algoritmos , Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Imageamento por Ressonância Magnética/métodos , Modelos Neurológicos , Simulação por Computador , Humanos
18.
Magn Reson Imaging ; 26(7): 968-77, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18508217

RESUMO

The increased blood oxygenation level-dependent contrast available at high field makes the implementation of combined EEG/fMRI experiments at 7 T highly worthwhile from the point of view of fMRI data quality, but the higher field poses greater technical challenges for achieving good quality EEG data. A study of the feasibility of recording EEG signals from human subjects at 7 T using a commercially available, MR-compatible EEG system has therefore been carried out. This involved systematic measurement of the sources of noise in EEG recordings made in the 7 T scanner and measurement of RF heating effects on a gel phantom in the presence of a 32-electrode EEG cap. Having found no significant safety concerns and identified a set-up (involving switching off the magnet's cryo-cooler pumps and mounting the EEG amplifier on a cantilever) that limited scanner-induced noise, combined EEG/fMRI experiments employing visual stimulation were then successfully carried out on two human subjects. With the use of beamformer-based analysis of the EEG data, driven responses and alpha-band, event-related desynchronisation were identified in both subjects.


Assuntos
Mapeamento Encefálico/métodos , Eletroencefalografia/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Artefatos , Estudos de Viabilidade , Humanos , Processamento de Imagem Assistida por Computador , Estimulação Luminosa , Processamento de Sinais Assistido por Computador , Temperatura
19.
Read Writ ; 31(3): 627-648, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29456292

RESUMO

The technical adequacy of CBM maze-scores as indicators of reading level and growth for seventh-grade secondary-school students was examined. Participants were 452 Dutch students who completed weekly maze measures over a period of 23 weeks. Criterion measures were school level, dyslexia status, scores and growth on a standardized reading test. Results supported the technical adequacy of maze scores as indicators of reading level and growth. Alternate-form reliability coefficients were significant and intermediate to high. Mean maze scores showed significant increase over time, students' growth trajectories differed, and students' initial performance levels (intercepts) and growth rates (slopes) were not correlated. Maze reading level and growth were related to reading level and/or growth on criterion measures. A nonlinear model provided a better fit for the data than a linear model. Implications for use of CBM maze-scores for data-based decision-making are discussed.

20.
Peptides ; 100: 165-172, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29412816

RESUMO

Dipeptidyl peptidase type 4 (DPP-4) inhibitors represent an important class of glucose-lowering drug for type 2 diabetes. DPP-4 enzyme activity has been observed to be significantly altered in type 2 diabetes. Here, the role of DPP-4 was examined in a high fat fed (HFF) mouse model of insulin resistance. HFF mice had an increased bodyweight (p < .01), were hyperglycaemic (p < .01) and hyperinsulinaemic (p < .05). Compared to normal diet, HFF mice exhibited increased plasma DPP-4 activity (p < .01). Tissue distribution patterns in lean and HFF mice demonstrated highest levels of DPP-4 activity in lung (20-26 µmol/min/mg protein) and small intestine (13-14 µmol/min/mg protein), and lowest activity in the spleen (3.8 µmol/min/mg protein). Modulation of DPP-4 activity by high fat feeding was observed in several tissues with increases in the lung (p < .05), liver (p < .05), kidney (p < .05) and pancreas (p < .05). With a high fat diet, DPP-4 gene expression was upregulated in the liver (p < .001) and downregulated in the pancreas (p < 0.001) and small intestine (p < .001). Immunohistochemical analysis revealed increased DPP-4 immunostaining localised primarily in the pancreatic islets of HFF mice (p < .01) with no change in islet GLP-1 expression. Treatment of HFF mice with metformin for 21-days resulted in inhibition of circulating DPP-4 activity (p < .05), decreased blood glucose (p < .05) and increased GLP-1 gene expression (p < .001). These data indicate that DPP-4 is modulated in a tissue specific manner and is dependent on physiological conditions such as hyperglycaemia and insulin resistance, suggesting a significant role in disorders such as diabetes.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Dipeptidil Peptidase 4/genética , Resistência à Insulina/genética , Obesidade/tratamento farmacológico , Animais , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Dieta Hiperlipídica/efeitos adversos , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/administração & dosagem , Regulação da Expressão Gênica/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/genética , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Glucose/metabolismo , Humanos , Hipoglicemiantes/administração & dosagem , Insulina/genética , Insulina/metabolismo , Secreção de Insulina/efeitos dos fármacos , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/patologia , Metformina/administração & dosagem , Camundongos , Obesidade/etiologia , Obesidade/metabolismo , Obesidade/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA