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1.
PLoS Comput Biol ; 19(1): e1010750, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36602968

RESUMO

Open, reproducible, and replicable research practices are a fundamental part of science. Training is often organized on a grassroots level, offered by early career researchers, for early career researchers. Buffet style courses that cover many topics can inspire participants to try new things; however, they can also be overwhelming. Participants who want to implement new practices may not know where to start once they return to their research team. We describe ten simple rules to guide participants of relevant training courses in implementing robust research practices in their own projects, once they return to their research group. This includes (1) prioritizing and planning which practices to implement, which involves obtaining support and convincing others involved in the research project of the added value of implementing new practices; (2) managing problems that arise during implementation; and (3) making reproducible research and open science practices an integral part of a future research career. We also outline strategies that course organizers can use to prepare participants for implementation and support them during this process.

2.
Eur J Neurosci ; 50(11): 3855-3872, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31344285

RESUMO

Older adults display difficulties in encoding and retrieval of information, resulting in poorer memory. This may be due to an inability of older adults to engage elaborative encoding strategies during learning. This study examined behavioural and electrophysiological effects of explicit cues to self-initiate learning during encoding and subsequent recognition of words in younger adults (YA), older control adults (OA) and older adults with relative memory impairment (OD). The task was a variation of the old/new paradigm, some study items were preceded by a cue to learn the word (L) while others by a do not learn cue (X). Behaviourally, YA outperformed OA and OD on the recognition task, with no significant difference between OA and OD. Event-related potentials at encoding revealed enhanced early visual processing (70-140 ms) for L- versus X-words in young and old. Only YA exhibited a greater late posterior positivity (LPP; 200-500 ms) for all words during encoding perhaps reflecting superior encoding strategy. During recognition, only YA differentiated L- versus X-words with enhanced frontal P200 (150-250 ms) suggesting impaired early word selection for retrieval in older groups; however, OD had enhanced P200 activity compared to OA during L-word retrieval. The LPP (250-500 ms) was reduced in amplitude for L-words compared to both X- and new words. However, YA showed greater LPP amplitude for all words compared to OA. For older groups, we observed reduced left parietal hemispheric asymmetry apparent in YA during encoding and recognition, especially for OD. Findings are interpreted in the light of models of compensation and dedifferentiation associated with age-related changes in memory function.


Assuntos
Eletroencefalografia/métodos , Aprendizagem/fisiologia , Transtornos da Memória/fisiopatologia , Desempenho Psicomotor/fisiologia , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Memória/fisiologia , Transtornos da Memória/diagnóstico , Tempo de Reação/fisiologia , Reconhecimento Psicológico/fisiologia , Adulto Jovem
3.
Exp Brain Res ; 216(4): 621-33, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22143870

RESUMO

The current study examined the EEG of young, old and old declined adults performing a visual paired associate task. In order to examine the effects of encoding context and stimulus repetition, target pairs were presented on either detailed or white backgrounds and were repeatedly presented during both early and late phases of encoding. Results indicated an increase in P300 amplitude in the right parietal cortex from early to late stages of encoding in older declined adults, whereas both younger adults and older controls showed a reduction in P300 amplitude in this same area from early to late phase encoding. In the right hemisphere, stimuli encoded with a white background had larger P300 amplitudes than stimuli presented with a detailed background; however, in the left hemisphere, in the later stages of encoding, stimuli presented with a detailed background had larger amplitudes than stimuli presented with a white background. Behaviourally, there was better memory for congruent stimuli reinstated with a detailed background, but this finding was for older controls only. During recognition, there was a general trend for congruent stimuli to elicit a larger amplitude response than incongruent stimuli, suggesting a distinct effect of context reinstatement on underlying patterns of physiological responding. However, behavioural data suggest that older declined adults showed no memory benefits associated with context reinstatement. When compared with older declined adults, younger adults had larger P100 amplitude responses to stimuli presented during recognition, and overall, younger adults had faster recognition reaction times than older control and older declined adults. Further analysis of repetition effects and context-based hemispheric asymmetry may prove informative in identifying declining memory performance in the elderly, potentially before it becomes manifested behaviourally.


Assuntos
Envelhecimento/fisiologia , Aprendizagem por Associação/fisiologia , Transtornos Cognitivos/fisiopatologia , Potenciais Evocados/fisiologia , Transtornos da Memória/fisiopatologia , Reconhecimento Visual de Modelos/fisiologia , Idoso , Envelhecimento/psicologia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/psicologia , Diagnóstico Precoce , Humanos , Transtornos da Memória/diagnóstico , Transtornos da Memória/psicologia , Adulto Jovem
4.
Neuroimage Clin ; 34: 102983, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35287090

RESUMO

It is important to identify accurate markers of psychiatric illness to aid early prediction of disease course. Subclinical psychotic experiences (PEs) are important risk factors for later mental ill-health and suicidal behaviour. This study used machine learning to investigate neuroanatomical markers of PEs in early and later stages of adolescence. Machine learning using logistic regression using Elastic Net regularization was applied to T1-weighted and diffusion MRI data to classify adolescents with subclinical psychotic experiences vs. controls across 3 timepoints (Time 1:11-13 years, n = 77; Time 2:14-16 years, n = 56; Time 3:18-20 years, n = 40). Neuroimaging data classified adolescents aged 11-13 years with current PEs vs. controls returning an AROC of 0.62, significantly better than a null model, p = 1.73e-29. Neuroimaging data also classified those with PEs at 18-20 years (AROC = 0.59;P = 7.19e-10) but performance was at chance level at 14-16 years (AROC = 0.50). Left hemisphere frontal regions were top discriminant classifiers for 11-13 years-old adolescents with PEs, particularly pars opercularis. Those with future PEs at 18-20 years-old were best distinguished from controls based on left frontal regions, right-hemisphere medial lemniscus, cingulum bundle, precuneus and genu of the corpus callosum (CC). Deviations from normal adolescent brain development in young people with PEs included an acceleration in the typical pattern of reduction in left frontal thickness and right parietal curvature, and accelerated progression of microstructural changes in right white matter and corpus callosum. These results emphasise the importance of multi-modal analysis for understanding adolescent PEs and provide important new insights into early phenotypes for psychotic experiences.


Assuntos
Transtornos Mentais , Transtornos Psicóticos , Substância Branca , Adolescente , Biomarcadores , Encéfalo/diagnóstico por imagem , Humanos , Aprendizado de Máquina , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/psicologia
5.
Psychol Aging ; 36(2): 252-267, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33539151

RESUMO

The consistently observed age-accompanied diminution in mind-wandering stands seemingly opposed to accounts that present mind-wandering as a failure of executive control. This study examined the impact of aging on the frequency and phenomenology of mind-wandering and investigated distinct variables mediating age-related differences in unintentional and intentional mind-wandering. Thirty-four younger and 34 healthy older adults completed a neuropsychological test battery and contrast change detection task embedded with experience sampling probes asking participants to discriminate the nature of their thoughts. Results revealed age-related decreases in unintentional and intentional mind-wandering, but equivalent task accuracy. Parallel mediations demonstrated that older adults reduced their unintentional mind-wandering through having less anxiety and greater task engagement than younger adults. Despite the evidence of age-related decline on cognitive function tests, neither executive function nor task demand variables further contributed to the model. Our results adjudicate between competing theories, highlighting the roles of affective and motivational factors in unintentional mind-wandering. Intentional mind-wandering showed no significant associations with the neuropsychological measures; however, intentional mind-wandering was associated with more false alarms, which was mediated by greater reaction time variability (RTV). In the context of the exploitation/exploration framework, we suggest that younger adults were more inclined to intentionally mind-wander, indexed by increased RTV, while preserving comparable performance accuracy to older adults. Conversely, older adults exploited greater task focus, marked by reduced RTV, with less bias toward, or resources for, exploration of the mind-wandering space. Therefore, dispositional and strategic factors should be considered in future investigations of mind-wandering across the lifespan. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Envelhecimento/psicologia , Atenção/fisiologia , Adolescente , Adulto , Idoso , Função Executiva/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tempo de Reação/fisiologia , Adulto Jovem
6.
J Psychiatr Res ; 130: 137-151, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32818662

RESUMO

The location, extent and progression of longitudinal morphometric changes after first-episode of psychosis (FEP) remains unclear. We investigated ventricular and cortico-subcortical regions over a 3-year period in FEP patients compared with healthy controls. High resolution 1.5T T1-weighted MR images were obtained at baseline from 28 FEP patients at presentation and 28 controls, and again after 3-years. The longitudinal FreeSurfer pipeline (v.5.3.0) was used for regional volumetric and cortical reconstruction image analyses. Repeated-measures ANCOVA and vertex-wise linear regression analyses compared progressive changes between groups in subcortical structures and cortical thickness respectively. Compared with controls, patients displayed progressively reduced volume of the caudate [F (1,51)=5.86, p=0.02, Hedges' g=0.66], putamen [F (1,51)=6.06, p=0.02, g=0.67], thalamus [F (1,51)=6.99, p=0.01, g=0.72] and increased right lateral ventricular volume [F (1, 51)=4.03, p=0.05], and significantly increased rate of cortical thinning [F (1,52)=5.11, p=0.028)] at a mean difference of 0.84% [95% CI (0.10, 1.59)] in the left lateral orbitofrontal region over the 3-year period. In patients, greater reduction in putamen volume over time was associated with lower cumulative antipsychotic medication dose (r=0.49, p=0.01), and increasing lateral ventricular volume over time was associated with worsening negative symptoms (r=0.41, p=0.04) and poorer global functioning (r= -0.41, p=0.04). This study demonstrates localised progressive structural abnormalities in the cortico-striato-thalamo-cortical circuit after the onset of psychosis, with increasing ventricular volume noted as a neuroanatomical marker of poorer clinical and functional outcome.


Assuntos
Antipsicóticos , Transtornos Psicóticos , Antipsicóticos/uso terapêutico , Humanos , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Imageamento por Ressonância Magnética , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/tratamento farmacológico
7.
Transl Neurosci ; 8: 117-126, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29662701

RESUMO

BACKGROUND: Verbal learning (VL) and fluency (VF) are prominent cognitive deficits in psychosis, of which the precise neuroanatomical contributions are not fully understood. We investigated the arcuate fasciculus (AF) and its associated cortical regions to identify structural abnormalities contributing to these verbal impairments in early stages of psychotic illness. METHODS: Twenty-six individuals with recent-onset psychosis and 27 healthy controls underwent cognitive testing (MATRICS Consensus Cognitive Battery) and structural/diffusion-weighted MRI. Bilaterally, AF anisotropy and cortical thickness, surface area and volume of seven cortical regions were investigated in relation to VL and VF performance in both groups. RESULTS: Reduced right superior temporal gyrus surface area and volume related to better VF in controls. In psychosis, greater right pars opercularis volume and reduced left lateralization of this region related to better VL, while greater right long AF fractional anisotropy and right pars orbitalis volume related to better VF, these findings not present in controls. Psychosis had reduced right pars orbitalis thickness compared to controls. CONCLUSION: Anatomical substrates for normal processing of VL and VF appear altered in recent-onset psychosis. A possible aberrant role of the right hemisphere arcuate fasciculus and fronto-temporal cortical regions in psychosis may contribute to deficits in VL and VF.

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