Cortical Thickness and Episodic Memory Impairment in Systemic Lupus Erythematosus.

BACKGROUND AND PURPOSE: The purpose of this study was to investigate differences in brain cortical thickness of systemic lupus erythematosus (SLE) patients with and without episodic memory impairment and healthy controls. METHODS: We studied 51 patients divided in 2 groups (SLE with episodic memory deficit, n = 17; SLE without episodic memory deficit, n = 34) by the Rey Auditory Verbal Learning Test and 34 healthy controls. Groups were paired based on sex, age, education, Mini-Mental State Examination score, and accumulation of disease burden. Cortical thickness from magnetic resonance imaging scans was determined using the FreeSurfer software package. RESULTS: SLE patients with episodic memory deficits presented reduced cortical thickness in the left supramarginal cortex and superior temporal gyrus when compared to the control group and in the right superior frontal, caudal, and rostral middle frontal and precentral gyri when compared to the SLE group without episodic memory impairment considering time since diagnosis of SLE as covaried. There were no significant differences in the cortical thickness between the SLE without episodic memory and control groups. CONCLUSIONS: Different memory-related cortical regions thinning were found in the episodic memory deficit group when individually compared to the groups of patients without memory impairment and healthy controls.

Global Cognitive Impairment in Systemic Lupus Erythematosus Patients: A Structural MRI Study.

OBJECTIVE: This study investigated differences in subcortical brain volumes of SLE patients with cognitive deficits (SLE-CD) and SLE patients with normal cognitive performance (SLE-CN), regardless of the presence of other neuropsychiatric symptoms. METHOD: We studied 40 patients divided into two-matched groups (SLE-CD n = 20; SLE-CN n = 20), with age ranging from 21 to 63 years old (100 % female) and 14.73 ± 10.18 years of diagnosis. Magnetic resonance imaging exams were performed on a 1.5 T scanner. A neuropsychological flexible battery was applied individually, including reasoning/problem-solving, praxis, episodic and working memory, processing speed, language/fluency, executive functions (inhibition and flexibility), and sustained attention. Z score ≤ - 2.0 in any dimension was considered as a cut-off for being considered to possess cognitive deficits. One-way analyses of covariance (ANCOVA) were performed to compare the brain structure volumes between groups. The analyses were controlled for the effects of lupus-related neuropsychiatric disorders. RESULTS: SLE patients with cognitive deficits had significantly smaller volumes in the left hippocampus, amygdala, and the right hippocampus than SLE patients without cognitive deficits. CONCLUSION: SLE patients with cognitive deficits appeared to have reduced temporal lobe structures when compared with SLE without cognitive deficits. These results corroborate a systems vulnerability model that investigated temporal lobe vulnerability during normal aging and in other neurological disorders.

Evaluation of white matter integrity in systemic lupus erythematosus by diffusion tensor magnetic resonance imaging: a study using tract-based spatial statistics.

INTRODUCTION: The aim of this study was to evaluate the white matter integrity in brains of patients with systemic lupus erythematosus (SLE) using a voxel-based analyses of diffusion tensor imaging (DTI) data. METHODS: Fifty-seven patients with SLE were compared to 36 control patients who were matched by gender, age, education, and Mini Mental State Examination score. DTI was performed along 30 noncollinear directions in a 1.5 Tesla scanner. For tract-based spatial statistics (TBSS), a white matter skeleton was created, and a permutation-based inference with 5000 permutations and a threshold of p < 0.05 was used to identify abnormalities in fractional anisotropy (FA). The mean (MD), radial (RD), and axial diffusivities (AD) were also projected onto the mean FA skeleton. RESULTS: We found a significant decrease of global FA in SLE patients compared to controls. The areas of reduced FA included the right superior corona radiata, the right superior longitudinal fasciculus, the body of the corpus callosum, the right inferior fronto-occipital fasciculus, the right thalamic radiation, and the right uncinate fasciculus. Patients with SLE also had increased AD and RD in several areas. Substantial overlap of areas with increased AD and RD occurred and were spatially much more extensive than the areas of reduced FA. CONCLUSION: Significant increases of AD values were concordant to those of RD and MD and more extensive than FA changes. Analyzing all diffusivity parameters, using TBSS, can detect more white matter microstructural changes in patients with SLE than analyzing FA alone.

Regional Cerebral Gray Matter Volume in HIV-Positive Patients with Executive Function Deficits.

PURPOSE: To evaluate whether human immunodeficiency virus (HIV)-positive patients with and without executive functions deficits and healthy control subjects differ on cortical thickness and subcortical brain structures volume in vivo. METHODS: In total, 34 HIV-positive patients with executive functions deficits were compared with 13 HIV-positive patients without executive functions deficits and 19 gender-, age-, and education-matched control subjects. Executive functions impairments were classified by performance on the Wisconsin card sorting test. T1 3-dimensional magnetization prepared rapid gradient echo-weighted imaging was performed using a 1.5 Tesla (magnetic resonance) MR scanner. FreeSurfer software was used to perform cortical reconstruction and volumetric segmentation of subcortical gray matter structures. RESULTS: HIV-positive patients with executive functions deficits had smaller volumes in the right and left caudate compared with the HIV-positive patients without executive functions deficits and control groups. In addition, HIV-positive patients with executive functions deficits had smaller volumes in their left accumbens, right putamen, and globus pallidum compared with the control group. No significant differences in cortical thickness were observed between the groups. CONCLUSION: HIV-positive patients with executive functions deficits have reduced volumes of several subcortical structures, primarily in the caudate nucleus.

Episodic memory impairment in systemic lupus erythematosus: involvement of thalamic structures.

Episodic memory deficits in systemic lupus erythematosus (SLE) have been frequently reported in the literature; however, little is known about the neural correlates of these deficits. We investigated differences in the volumes of different brain structures of SLE patients with and without episodic memory impairments diagnosed by the Rey Auditory Verbal Learning Test (RAVLT). Groups were paired based on age, education, sex, Mini Mental State Examination score, accumulation of disease burden (SLICC), and focused attention dimension score. Patients underwent magnetic resonance imaging (MRI). Cortical volumetric reconstruction and segmentation of the MR images were performed with the FreeSurfer software program. SLE patients with episodic memory deficits presented shorter time of diagnosis than SLE patients without episodic memory deficits. ANOVA revealed that SLE patients with episodic memory deficits had a larger third ventricle volume than SLE patients without episodic memory deficits and controls. Additionally, covariance analysis indicated group effects on the bilateral thalamus and on the third ventricle. Our findings indicate that episodic memory may be impaired in SLE patients with normal hippocampal volume. In addition, the thalamus may undergo volumetric changes associated with episodic memory loss in SLE.

Working memory training and poetry-based stimulation programs: are there differences in cognitive outcome in healthy older adults?

BACKGROUND: Neuropsychological interventions have been mainly applied with clinical populations, in spite of the need of preventing negative changes across life span. Among the few studies of cognitive stimulation in elderly, surprisingly there is no enough research comparing direct and indirect active stimulation programs. OBJECTIVE: This study aims to verify wheter there are differences between two cognitive interventions approaches in older adults: a structured Working Memory (WM) Training Program versus a Poetry-based Stimulation Program. METHODS: Fourteen older adults were randomly assigned to participate into one of the two intervention groups. The assessed neurocognitive components were attention, episodic and working memory, communicative and executive functions. WM Training activities were based on Baddeley's model; Poetry-based Stimulation Program was composed by general language activities. Data were analyzed with one-way ANCOVA with Delta scores and pre and post-training tests raw scores. RESULTS: WM group improved performance on WM, inhibition, and cognitive flexibility measures, while Poetry group improved on verbal fluency and narrative discourse tasks. DISCUSSION: Both approaches presented benefits; however WM Training improved its target function with transfer effects to executive functions, being useful for future studies with a variety of dementias. Poetry-based Stimulation also improved complex linguistic abilities. Both approaches may be helpful as strategies to prevent dysfunctional aging changes.

Efeito de um programa de treinamento da memória de trabalho em adultos idosos / Effect of a working memory training program in older adults

Este estudo objetivou examinar os efeitos de um Treinamento da Memória de Trabalho (TMT) em idosos saudáveis. Vinte participantes compuseram a amostra final, onze do grupo experimental (TMT) e nove do controle (socialização). Todos foram submetidos a uma avaliação neuropsicológica pré e pós-intervenção. Os encontros foram realizados uma vez por semana, durante três meses. Houve melhora significativa, no grupo experimental, em atenção concentrada, aprendizagem, memória de curto prazo e episódica, e no grupo controle, em um menor número de variáveis, na atenção concentrada e memória episódica. O TMT parece ter promovido efeito de transferência, principalmente na memória episódica, que é relacionada diretamente aos subsistemas da memória de trabalho (MT), sugerindo que o TMT pode ser útil no contexto da neuropsicologia do envelhecimento.

The present study examined the effects of a Working Memory Training (WMT) in healthy elderly. Twenty participants comprised the final sample, eleven from the experimental group (WMT) and nine from the control group (socialization). Every subject underwent a neuropsychological evaluation pre and post-intervention. The meetings were held once a week, for three months. Results indicated that subjects in the experimental group improved cognitive functions related to concentrated attention, learning, short-term and episodic memory. Subjects in the control group also demonstrated, in a smaller number of variables, improvement in concentrated attention and episodic memory. WMT seems to have generated a transfer effect, especially to episodic memory, which is directly related to the subsystem of working memory (WM), suggesting that WMT may be useful in the context of the neuropsychology of aging.

Correlação entre espessura cortical frontal e desempenho de funções executivas em pacientes com infecção pelo vírus da imunodeficiência humana / Correlation between frontal cortical thickness and executive functions performance in patients with human immunodeficiency virus infection

OBJETIVO: Investigar a relação entre a espessura cortical medida pela ressonância magnética em regiões frontais e o desempenho em instrumentos que avaliam funções executivas em pacientes com HIV positivo. MATERIAIS E MÉTODOS: Participaram deste estudo 22 pacientes HIV-positivos, com déficits em funções executivas, sob terapia antirretroviral, idades entre 45 e 65 anos e escolaridade entre 3 e 20 anos. Foi realizada ressonância magnética com sequências convencionais, T1 3D, processado pelo Freesurfer para verificar espessura cortical. Instrumentos de avaliação das funções executivas: Teste de Trilhas, Wisconsin, Hayling, Dígitos (WAIS-III), fluência verbal ortográfica e Stroop. Para análise da relação espessura versus cognição, utilizou-se coeficiente de correlação de Pearson. RESULTADOS: Correlações significativas foram encontradas entre escores de: Wisconsin e espessura das regiões pré-central e orbitofrontal lateral à direita e pré-central esquerda; Teste de Trilhas e espessura da área pré-central direita e cíngulo anterior caudal esquerdo; e Teste Hayling e espessura da área lateral orbitofrontal esquerda. CONCLUSÃO: As correlações existentes entre medidas de espessura cortical pela ressonância magnética e desempenho cognitivo sugerem que os déficits executivos em pacientes HIV-positivos relacionam-se a uma redução da espessura cortical das regiões frontais.

OBJECTIVE: To investigate the correlation between frontal regions cortical thickness measured by magnetic resonance imaging of HIV-positive patients and their performance on instruments for assessing executive functions. MATERIALS AND METHODS: The present study included 22 HIV-positive patients in the age range from 45 to 65, schooling ranging between three and 20 years, with executive functions deficit and undergoing antiretroviral therapy. Magnetic resonance imaging was performed with conventional T1-weighted, 3D sequences and the images were processed with the Freesurfer software to measure cortical thickness. The following instruments were utilized to evaluate the patients' executive functions: Trail Making, Wisconsin, Hayling, working memory (WAIS-III), verbal fluency and Stroop tests. The Pearson's correlation coefficient was utilized in the data statistical analysis. RESULTS: Significant correlations were found between: Wisconsin scores and the thickness of the right pre-central, lateral and left pre-central orbitofrontal regions; Trail Making scores and thickness of right pre-central and left anterior caudal cingulate areas; and Hayling Test scores and thickness of the left lateral orbitofrontal area. CONCLUSION: Correlations between cortical thickness measurements by magnetic resonance imaging and cognitive performance suggest that the executive function deficit in HIV-positive patients are related to a reduction in the thickness of the frontal cortex.

Theoretical, behavioral and neuroimage evidence on discourse processing aging

A growing interest in cognition in aging has been observed because of both the epidemiologic factor of an increase in the lifespan of the world's population and the cognitive changes behaviorally and biologically detectable in this population. The most complex of language components and fundamental in social interaction, discourse production and comprehension are among the most scarcely explored cognitive functions in this context. This review presents and discusses discourse processing in healthy aging with regard to theoretical, behavioral, and neuroimaging evidence. Cognitive and neurobiological models are reviewed, such as the Hemispheric Asymmetry Reduction in Older Adults (HAROLD) model and the Posterior-Anterior Shift in Aging (PASA) model. Among the neuropsycholinguistic research developed to characterize discourse processing in aging individuals, which has contributed to the prevention and treatment of language impairment and the maintenance of communicative competence in aging, studies on the relationship between discourse and working memory, attention, and some executive components are discussed. Regarding neuroimaging data, very few studies that have included cognitive tasks and discourse stimuli were found. Such studies suggest that discourse processing requires not only the participation of both brain hemispheres, but also a more prominent activation of frontal regions. Considering the great complexity and usefulness of discourse in elderly adults' daily communication and the emergence of cognitive deficits related to aging in complex information processing, the necessity of further behavioral and neuroimaging studies, including discourse processing tasks, comparing tasks involving executive, attentional, and mnemonic demands becomes evident.