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1.
JAMA Netw Open ; 7(2): e2355901, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38349653

RESUMO

Importance: Few investigations have evaluated rates of brain-based magnetic resonance imaging (MRI) incidental findings (IFs) in large lifespan samples, their stability over time, or their associations with health outcomes. Objectives: To examine rates of brain-based IFs across the lifespan, their persistence, and their associations with phenotypic indicators of behavior, cognition, and health; to compare quantified motion with radiologist-reported motion and evaluate its associations with IF rates; and to explore IF consistency across multiple visits. Design, Setting, and Participants: This cross-sectional study included participants from the Nathan Kline Institute-Rockland Sample (NKI-RS), a lifespan community-ascertained sample, and the Healthy Brain Network (HBN), a cross-sectional community self-referred pediatric sample focused on mental health and learning disorders. The NKI-RS enrolled participants (ages 6-85 years) between March 2012 and March 2020 and had longitudinal participants followed up for as long as 4 years. The HBN enrolled participants (ages 5-21 years) between August 2015 and October 2021. Clinical neuroradiology MRI reports were coded for radiologist-reported motion as well as presence, type, and clinical urgency (category 1, no abnormal findings; 2, no referral recommended; 3, consider referral; and 4, immediate referral) of IFs. MRI reports were coded from June to October 2021. Data were analyzed from November 2021 to February 2023. Main Outcomes and Measures: Rates and type of IFs by demographic characteristics, health phenotyping, and motion artifacts; longitudinal stability of IFs; and Euler number in projecting radiologist-reported motion. Results: A total of 1300 NKI-RS participants (781 [60.1%] female; mean [SD] age, 38.9 [21.8] years) and 2772 HBN participants (976 [35.2%] female; mean [SD] age, 10.0 [3.5] years) had health phenotyping and neuroradiology-reviewed MRI scans. IFs were common, with 284 of 2956 children (9.6%) and 608 of 1107 adults (54.9%) having IFs, but rarely of clinical concern (category 1: NKI-RS, 619 [47.6%]; HBN, 2561 [92.4%]; category 2: NKI-RS, 647 [49.8%]; HBN, 178 [6.4%]; category 3: NKI-RS, 79 [6.1%]; HBN, 30 [1.1%]; category 4: NKI-RS: 12 [0.9%]; HBN, 6 [0.2%]). Overall, 46 children (1.6%) and 79 adults (7.1%) required referral for their IFs. IF frequency increased with age. Elevated blood pressure and BMI were associated with increased T2 hyperintensities and age-related cortical atrophy. Radiologist-reported motion aligned with Euler-quantified motion, but neither were associated with IF rates. Conclusions and Relevance: In this cross-sectional study, IFs were common, particularly with increasing age, although rarely clinically significant. While T2 hyperintensity and age-related cortical atrophy were associated with BMI and blood pressure, IFs were not associated with other behavioral, cognitive, and health phenotyping. Motion may not limit clinical IF detection.


Assuntos
Encéfalo , Achados Incidentais , Adulto , Feminino , Humanos , Criança , Masculino , Estudos Transversais , Encéfalo/diagnóstico por imagem , Atrofia , Imageamento por Ressonância Magnética
2.
Sci Data ; 9(1): 300, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35701428

RESUMO

Most psychiatric disorders are chronic, associated with high levels of disability and distress, and present during pediatric development. Scientific innovation increasingly allows researchers to probe brain-behavior relationships in the developing human. As a result, ambitions to (1) establish normative pediatric brain development trajectories akin to growth curves, (2) characterize reliable metrics for distinguishing illness, and (3) develop clinically useful tools to assist in the diagnosis and management of mental health and learning disorders have gained significant momentum. To this end, the NKI-Rockland Sample initiative was created to probe lifespan development as a large-scale multimodal dataset. The NKI-Rockland Sample Longitudinal Discovery of Brain Development Trajectories substudy (N = 369) is a 24- to 30-month multi-cohort longitudinal pediatric investigation (ages 6.0-17.0 at enrollment) carried out in a community-ascertained sample. Data include psychiatric diagnostic, medical, behavioral, and cognitive phenotyping, as well as multimodal brain imaging (resting fMRI, diffusion MRI, morphometric MRI, arterial spin labeling), genetics, and actigraphy. Herein, we present the rationale, design, and implementation of the Longitudinal Discovery of Brain Development Trajectories protocol.


Assuntos
Encéfalo , Conectoma , Saúde Mental , Adolescente , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Criança , Imagem de Difusão por Ressonância Magnética , Humanos
3.
Neurology ; 92(9): e905-e916, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30700591

RESUMO

OBJECTIVE: To determine efficacy of aerobic exercise for cognitive function in younger healthy adults. METHODS: In a randomized, parallel-group, observer-masked, community-based clinical trial, 132 cognitively normal individuals aged 20-67 with below median aerobic capacity were randomly assigned to one of two 6-month, 4-times-weekly conditions: aerobic exercise and stretching/toning. Efficacy measures included aerobic capacity; cognitive function in several domains (executive function, episodic memory, processing speed, language, and attention), everyday function, body mass index (BMI), and cortical thickness. RESULTS: Aerobic capacity increased significantly (ß = 2.718; p = 0.003), and BMI decreased significantly (ß = -0.596; p = 0.013) in the aerobic exercise but not in the stretching/toning condition. Executive function improved significantly in the aerobic exercise condition; this effect was moderated by age (ß = 0.018 SD/y; p = 0.028). At age 40, the executive function measure increased by 0.228 SD (95% confidence interval [CI] 0.007-0.448), and by 0.596 SD (95% CI 0.219-0.973) at age 60. Cortical thickness increased significantly in the aerobic exercise group in a left frontal region and did not interact with age. Controlling for age and baseline performance, individuals with at least one APOE ε4 allele showed less improvement in executive function with aerobic exercise (ß = 0.5129, 95% CI 0.0381-0.988; p = 0.0346). CONCLUSIONS: This randomized clinical trial demonstrates the efficacy of aerobic exercise for cognition in adults age 20-67. The effect of aerobic exercise on executive function was more pronounced as age increased, suggesting that it may mitigate age-related declines. Increased cortical thickness suggests that aerobic exercise contributes to brain health in individuals as young as age 20. CLINICALTRIALSGOV IDENTIFIER: NCT01179958. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for adults age 20-67 with below median aerobic capacity, aerobic exercise significantly improves executive function but not other measures of cognitive function.


Assuntos
Cognição , Função Executiva , Exercício Físico , Adulto , Fatores Etários , Idoso , Apolipoproteína E4/genética , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/diagnóstico por imagem , Tolerância ao Exercício , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tamanho do Órgão , Consumo de Oxigênio , Adulto Jovem
4.
J Int Neuropsychol Soc ; 24(5): 498-510, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29400264

RESUMO

OBJECTIVES: Emerging work reveals the neuroanatomic changes that compromise metacognition; however, little is known about the impact of premorbid factors. Research suggests that psychological variables influence the perception of cognition, but whether they influence the accuracy of those perceptions (i.e., metacognition) has not been directly examined. PARTICIPANTS AND METHODS: Using Latent Class Analysis (LCA), we tested for discrete personality (NEOFFI) and mood (STAI, BDI-II, and GDS) classes among a community-based cohort of 151 older adults, enrolled in the NKI-Rockland study. Metamemory was calculated by comparing subjective memory ratings (modified Cognitive Failures Questionnaire) to objective memory (Rey Auditory Verbal Learning Test) to determine the degree to which individuals were overconfident, underconfident, or accurate in their self-assessment. A generalized linear model was used to examine whether metamemory differed across the emergent classes. A one sample t test was used to determine whether the metamemory scores of the emergent classes were statistically significantly different from zero, that is, over or under confident. RESULTS: Two discrete classes emerged in the LCA: Class 1 was characterized predominantly by high extraversion and conscientiousness and low neuroticism and anxiety; Class 2 was characterized predominantly by low extraversion and conscientiousness and high neuroticism and anxiety. Metamemory differed significantly as a function of Class Membership (F(4,151)=5.42; p<.001), with Class 1 demonstrating accurate metamemory (M=0.21; SD=1.31) and Class 2 demonstrating under-confidence (M=-0.59; SD=1.39) in their memory. CONCLUSIONS: The significant association between psychological factors and metamemory knowledge accuracy suggests that such characteristics may be important to consider in the conceptualization, assessment, and treatment of metacognitive disturbances. (JINS, 2018, 24, 498-510).


Assuntos
Afeto , Metacognição , Personalidade , Autoavaliação (Psicologia) , Idoso , Idoso de 80 Anos ou mais , Envelhecimento Cognitivo/psicologia , Estudos de Coortes , Feminino , Humanos , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Inventário de Personalidade , Inquéritos e Questionários
5.
J Gerontol B Psychol Sci Soc Sci ; 73(6): 954-963, 2018 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-27633612

RESUMO

Objectives: Recent work has identified different aspects of executive function that may underlie cognitive changes associated with age. The current study used a multifactorial design to investigate age sensitivity in the ability to shift between different task sets and the interaction of this ability with several specific aspects of executive control. Method: A large, well-characterized sample of younger (n = 40) and clinically healthy older (n = 51) adults completed a task switching paradigm in which 3 aspects of executive control were manipulated between subjects: a) sensorimotor demand (the number of distinct stimulus-response options); b) stimulus-level interference (i.e., flanker effects); and c) updating/monitoring (the frequency of task switches). Results: Unique age-related deficits were observed for different aspects of local task switching performance costs and updating/monitoring, but not for interference. Sensorimotor demand was also an important additional factor that interacted with task switching performance. Discussion: Our findings suggest that task switching, coupled with infrequent and unexpected transitions from one task set to another, in the context of high motoric demands, is particularly difficult for older adults.


Assuntos
Função Executiva , Desempenho Psicomotor , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Envelhecimento/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Reação , Adulto Jovem
6.
Neuroimage ; 146: 157-170, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27836708

RESUMO

This data descriptor describes a repository of openly shared data from an experiment to assess inter-individual differences in default mode network (DMN) activity. This repository includes cross-sectional functional magnetic resonance imaging (fMRI) data from the Multi Source Interference Task, to assess DMN deactivation, the Moral Dilemma Task, to assess DMN activation, a resting state fMRI scan, and a DMN neurofeedback paradigm, to assess DMN modulation, along with accompanying behavioral and cognitive measures. We report technical validation from n=125 participants of the final targeted sample of 180 participants. Each session includes acquisition of one whole-brain anatomical scan and whole-brain echo-planar imaging (EPI) scans, acquired during the aforementioned tasks and resting state. The data includes several self-report measures related to perseverative thinking, emotion regulation, and imaginative processes, along with a behavioral measure of rapid visual information processing. Technical validation of the data confirms that the tasks deactivate and activate the DMN as expected. Group level analysis of the neurofeedback data indicates that the participants are able to modulate their DMN with considerable inter-subject variability. Preliminary analysis of behavioral responses and specifically self-reported sleep indicate that as many as 73 participants may need to be excluded from an analysis depending on the hypothesis being tested. The present data are linked to the enhanced Nathan Kline Institute, Rockland Sample and builds on the comprehensive neuroimaging and deep phenotyping available therein. As limited information is presently available about individual differences in the capacity to directly modulate the default mode network, these data provide a unique opportunity to examine DMN modulation ability in relation to numerous phenotypic characteristics.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiopatologia , Bases de Dados Factuais , Imageamento por Ressonância Magnética , Transtornos Mentais/fisiopatologia , Neurorretroalimentação , Adulto , Imagem Ecoplanar , Feminino , Humanos , Individualidade , Disseminação de Informação , Armazenamento e Recuperação da Informação , Masculino , Pessoa de Meia-Idade , Vias Neurais , Neuroimagem , Fenótipo , Adulto Jovem
7.
J Psychiatr Res ; 79: 21-27, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27131617

RESUMO

Impairment in social cognition, including emotion recognition, has been extensively studied in both Autism Spectrum Disorders (ASD) and Schizophrenia (SZ). However, the relative patterns of deficit between disorders have been studied to a lesser degree. Here, we applied a social cognition battery incorporating both auditory (AER) and visual (VER) emotion recognition measures to a group of 19 high-functioning individuals with ASD relative to 92 individuals with SZ, and 73 healthy control adult participants. We examined group differences and correlates of basic auditory processing and processing speed. Individuals with SZ were impaired in both AER and VER while ASD individuals were impaired in VER only. In contrast to SZ participants, those with ASD showed intact basic auditory function. Our finding of a dissociation between AER and VER deficits in ASD relative to Sz support modality-specific theories of emotion recognition dysfunction. Future studies should focus on visual system-specific contributions to social cognitive impairment in ASD.


Assuntos
Percepção Auditiva , Transtorno do Espectro Autista/psicologia , Reconhecimento Facial , Transtornos Psicóticos/psicologia , Psicologia do Esquizofrênico , Percepção Social , Adulto , Análise de Variância , Cognição , Feminino , Humanos , Masculino , Testes Psicológicos , Reconhecimento Psicológico
8.
Psychol Aging ; 30(4): 863-880, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26523693

RESUMO

The objective of the study was to examine variability across multiple prospective cohort studies in level and rate of cognitive decline by race/ethnicity and years of education. We compare data across studies, we harmonized estimates of common latent factors representing overall or general cognitive performance, memory, and executive function derived from the: (a) Washington Heights, Hamilton Heights, Inwood Columbia Aging Project (N = 4,115), (b) Spanish and English Neuropsychological Assessment Scales (N = 525), (c) Duke Memory, Health, and Aging study (N = 578), and (d) Neurocognitive Outcomes of Depression in the Elderly (N = 585). We modeled cognitive change over age for cognitive outcomes by race, education, and study. We adjusted models for sex, dementia status, and study-specific characteristics. The results found that for baseline levels of overall cognitive performance, memory, and executive function, differences in race and education tended to be larger than between-study differences and consistent across studies. This pattern did not hold for rate of cognitive decline: effects of education and race/ethnicity on cognitive change were not consistently observed across studies, and when present were small, with racial/ethnic minorities and those with lower education declining at faster rates. In this diverse set of datasets, non-Hispanic Whites and those with higher education had substantially higher baseline cognitive test scores. However, differences in the rate of cognitive decline by race/ethnicity and education did not follow this pattern. This study suggests that baseline test scores and longitudinal change have different determinants, and future studies to examine similarities and differences of causes of cognitive decline in racially/ethnically and educationally diverse older groups is needed.


Assuntos
Envelhecimento , Transtornos Cognitivos/psicologia , Escolaridade , Testes Neuropsicológicos , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/etnologia , Envelhecimento/fisiologia , Envelhecimento/psicologia , Cognição , Transtornos Cognitivos/etnologia , Etnicidade/psicologia , Etnicidade/estatística & dados numéricos , Função Executiva , Feminino , Hispânico ou Latino/psicologia , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos/estatística & dados numéricos , Estudos Prospectivos , Washington , População Branca/psicologia
9.
J Gerontol B Psychol Sci Soc Sci ; 70(4): 519-31, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24389122

RESUMO

OBJECTIVES: Poor quality of early life conditions has been associated with poorer late life cognition and increased risk of dementia. Early life physical development can be captured using adult measures of height and head circumference. Availability of resources may be reflected by socioeconomic indicators, such as parental education and family size. We sought to determine the association between early life development and experience and late life semantic memory, episodic memory, and executive functioning abilities, as well as rate of cognitive decline. METHOD: This study was conducted using the UC Davis Aging Diversity cohort, an ethnically diverse sample of Caucasian, African American, and Hispanic individuals from northern California. We used latent variable modeling to measure growth and childhood socioeconomic environment (SES) and examine their associations with longitudinal cognitive outcomes using mixed effects modeling. RESULTS: Growth was positively related to higher childhood SES. Higher childhood SES was associated with better semantic memory. Both low growth and low SES were associated with increased rate of cognitive decline. DISCUSSION: These findings demonstrate that early life experiences influence the trajectory of cognitive aging. Early life development and experience appears to provide a distal basis upon which additional risk and protective factors interact in the development of dementia.


Assuntos
Envelhecimento/etnologia , Desenvolvimento Infantil/fisiologia , Transtornos Cognitivos/etnologia , Função Executiva/fisiologia , Memória/fisiologia , Classe Social , Idoso , Idoso de 80 Anos ou mais , California/etnologia , Criança , Humanos , Acontecimentos que Mudam a Vida , Masculino , Memória Episódica
10.
Neuropsychology ; 28(6): 846-58, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24933483

RESUMO

OBJECTIVE: We examined the influence of a broad spectrum of life experiences on longitudinal cognitive trajectories in a demographically diverse sample of older adults. METHOD: Participants were 333 educationally, ethnically, and cognitively diverse older adults enrolled in a longitudinal aging study. Mixed-effects regression was used to measure baseline status in episodic memory, executive functioning, and semantic memory and change in a global cognition factor defined by change in these 3 domain-specific measures. We examined effects of life experience variables (literacy, childhood socioeconomic status, morphometric measures of physical development, life course physical and recreational activity) on longitudinal cognitive trajectories, covarying for age, apolipoprotein E (APOE) genotype and demographics (education, ethnicity, language). RESULTS: Non-Latino Whites had higher baseline cognition, but life experience variables attenuated ethnic differences in cognitive scores. Age, literacy, childhood socioeconomic status, and physical activity significantly influenced baseline cognition. Age, APOE ε4, and decline in intellectually and socially stimulating recreational activity from mid to late life were independently associated with increased late life cognitive decline. Higher literacy and late life recreational activity were associated with less decline. Literacy had similar effects for English and Spanish readers/speakers. Bilingual English and Spanish speakers did not differ from English Speakers in cognitive performance. CONCLUSIONS: Life experience variables, especially literacy level, were strongly related to baseline cognition and substantially attenuated effects of race/ethnicity and education. Cognitive change was best explained by age, APOE ε4, literacy, and current recreational activities. Literacy had robust associations with baseline cognition and cognitive change in both English and Spanish speakers.


Assuntos
Envelhecimento/psicologia , Transtornos Cognitivos/etnologia , Cognição , Função Executiva , Acontecimentos que Mudam a Vida , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Envelhecimento/etnologia , Apolipoproteína E4/genética , Transtornos Cognitivos/psicologia , Escolaridade , Feminino , Genótipo , Hispânico ou Latino/estatística & dados numéricos , Humanos , Individualidade , Idioma , Alfabetização , Estudos Longitudinais , Masculino , Memória Episódica , Pessoa de Meia-Idade , Classe Social , População Branca/psicologia , População Branca/estatística & dados numéricos
11.
Brain Behav ; 4(2): 143-57, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24683508

RESUMO

BACKGROUND: Disruption of the default-mode network (DMN) in healthy elders has been reported in many studies. METHODS: In a group of 51 participants (25 young, 26 elder) we examined DMN connectivity in subjects' native space. In the native space method, subject-specific regional masks (obtained independently for each subject) are used to extract regional fMRI times series. This approach substitutes the spatial normalization and subsequent smoothing used in prevailing methods, affords more accurate spatial localization, and provides the power to examine connectivity separately in the two hemispheres instead of averaging regions across hemispheres. RESULTS: The native space method yielded new findings which were not detectable by the prevailing methods. The most reliable and robust disruption in elders' DMN connectivity were found between supramarginal gyrus and superior-frontal cortex in the right hemisphere only. The mean correlation between these two regions in young participants was about 0.5, and dropped significantly to 0.04 in elders (P = 2.1 × 10(-5)). In addition, the magnitude of functional connectivity between these regions in the right hemisphere correlated with memory (P = 0.05) and general fluid ability (P = 0.01) in elder participants and with speed of processing in young participants (P = 0.008). These relationships were not observed in the left hemisphere. CONCLUSION: These findings suggest that analysis of DMN connectivity in subjects' native space can improve localization and power and that it is important to examine connectivity separately in each hemisphere.


Assuntos
Envelhecimento/fisiologia , Córtex Cerebral/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/fisiopatologia , Desempenho Psicomotor/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
PLoS One ; 8(9): e73645, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24023894

RESUMO

OBJECTIVE: To investigate the temporal ordering of cognitive and functional declines separately in older adults with or without Alzheimer's disease (AD). DESIGN AND SETTING: A community-based longitudinal study of aging and dementia in Northern Manhattan (Washington Heights/Hamilton Heights Inwood Columbia Aging Project) and a multicenter, clinic-based longitudinal study of prevalent AD at Columbia University Medical Center, Johns Hopkins School of Medicine, Massachusetts General Hospital, and the Hôpital de la Salpêtrière in Paris, France (the Predictors Study). PARTICIPANTS: 3,443 initially non-demented older adults (612 with eventual incident dementia) and 517 patients with AD. MAIN OUTCOME MEASURES: Cognitive measures included the modified Mini-Mental State Exam and composite scores of memory and language derived from a standardized neuropsychological battery. Function was measured with the Blessed Dementia Rating Scale, completed by the participant (in the sample of non-demented older adults) or an informant (in the sample of prevalent AD patients). Data were analyzed with autoregressive cross-lagged panel analysis. RESULTS: Cognitive scores more consistently predicted subsequent functional abilities than vice versa in non-demented older adults, participants with eventual incident dementia, and patients with prevalent AD. CONCLUSIONS: Cognitive declines appear to precede and cause functional declines prior to and following dementia diagnosis. Standardized neuropsychological tests are valid predictors of later functional changes in both non-demented and demented older adults.


Assuntos
Envelhecimento/fisiologia , Doença de Alzheimer/fisiopatologia , Cognição , Adulto , Doença de Alzheimer/diagnóstico , Feminino , Humanos , Estudos Longitudinais , Masculino
13.
J Anxiety Disord ; 27(6): 559-66, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23602352

RESUMO

Recent evidence supports a negative association between anxiety and cognitive control. Given age-related reductions in some cognitive abilities and the relation of late life anxiety to cognitive impairment, this negative association may be particularly relevant to older adults. This critical review conceptualizes anxiety and cognitive control from cognitive neuroscience and cognitive aging theoretical perspectives and evaluates the methodological approaches and measures used to assess cognitive control. Consistent with behavioral investigations of young adults, the studies reviewed implicate specific and potentially negative effects of anxiety on cognitive control processes in older adults. Hypotheses regarding the role of both aging and anxiety on cognitive control, the bi-directionality between anxiety and cognitive control, and the potential for specific symptoms of anxiety (particularly worry) to mediate this association, are specified and discussed.


Assuntos
Ansiedade/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Cognição/fisiologia , Inibição Psicológica , Envelhecimento , Ansiedade/complicações , Ansiedade/psicologia , Transtornos Cognitivos/complicações , Transtornos Cognitivos/psicologia , Humanos , Testes Neuropsicológicos , Neurociências
14.
Artigo em Inglês | MEDLINE | ID: mdl-21728889

RESUMO

Recent research has demonstrated benefits for older adults from training attentional control using a variable priority strategy, but the construct validity of the training task and the degree to which benefits of training transfer to other contexts are unclear. The goal of this study was to characterize baseline performance on the training task in a sample of 105 healthy older adults and to test for transfer of training in a subset (n = 21). Training gains after 5 days and extent of transfer was compared to another subset (n = 20) that served as a control group. Baseline performance on the training task was characterized by a two-factor model of working memory and processing speed. Processing speed correlated with the training task. Training gains in speed and accuracy were reliable and robust (ps <.001, η(2) = .57 to .90). Transfer to an analogous task was observed (ps <.05, η(2) = .10 to .17). The beneficial effect of training did not translate to improved performance on related measures of processing speed. This study highlights the robust effect of training and transfer to a similar context using a variable priority training task. Although processing speed is an important aspect of the training task, training benefit is either related to an untested aspect of the training task or transfer of training is limited to the training context.


Assuntos
Atenção/fisiologia , Avaliação Geriátrica , Ensino , Transferência de Experiência/fisiologia , Idoso , Análise Fatorial , Feminino , Humanos , Inibição Psicológica , Masculino , Memória de Curto Prazo/fisiologia , Processos Mentais/fisiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologia , Reprodutibilidade dos Testes , Estatística como Assunto
15.
IEEE Trans Vis Comput Graph ; 15(6): 1433-40, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19834218

RESUMO

Visual exploration is essential to the visualization and analysis of densely sampled 3D DTI fibers in biological specimens, due to the high geometric, spatial, and anatomical complexity of fiber tracts. Previous methods for DTI fiber visualization use zooming, color-mapping, selection, and abstraction to deliver the characteristics of the fibers. However, these schemes mainly focus on the optimization of visualization in the 3D space where cluttering and occlusion make grasping even a few thousand fibers difficult. This paper introduces a novel interaction method that augments the 3D visualization with a 2D representation containing a low-dimensional embedding of the DTI fibers. This embedding preserves the relationship between the fibers and removes the visual clutter that is inherent in 3D renderings of the fibers. This new interface allows the user to manipulate the DTI fibers as both 3D curves and 2D embedded points and easily compare or validate his or her results in both domains. The implementation of the framework is GPU based to achieve real-time interaction. The framework was applied to several tasks, and the results show that our method reduces the user's workload in recognizing 3D DTI fibers and permits quick and accurate DTI fiber selection.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Modelos Biológicos , Miofibrilas , Fibras Nervosas , Interface Usuário-Computador , Algoritmos , Animais , Encéfalo/anatomia & histologia , Análise por Conglomerados , Gráficos por Computador , Coração/anatomia & histologia , Membro Posterior , Suínos
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