Structural connectivity of the default mode network and cognition in Alzheimer's disease

Autor(es)

Weiler, Marina ^[1] ; de Campos, Brunno Machado ^[1] ; Nogueira, Mateus Henrique ^[1] ; Damasceno, Benito Pereira ^[2] ; Cendes, Fernando ^[1] ; Balthazar, Marcio L. F. ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Univ Campinas Unicamp, Dept Neurol, Neuroimaging Lab, Campinas, SP - Brazil

^[2] Univ Campinas Unicamp, Unit Neuropsychol & Neurolinguist, Depat intent Neurol, Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PSYCHIATRY RESEARCH-NEUROIMAGING; v. 223, n. 1, p. 15-22, JUL 30 2014.
• Citações Web of Science: 13

Resumo

Disconnectivity between the Default Mode Network (DMN) nodes can cause clinical symptoms and cognitive deficits in Alzheimer's disease (AD). We aimed to examine the structural connectivity between DMN nodes, to verify the extent in which white matter disconnection affects cognitive performance. MRI data of 76 subjects (25 mild AD, 21 amnestic Mild Cognitive Impairment subjects and 30 controls) were acquired on a 3.0 T scanner. ExploreDTI software (fractional Anisotropy threshold = 0.25 and the angular threshold = 60 degrees) calculated axial, radial, and mean diffusivities, fractional anisotropy and streamline count. AD patients showed lower fractional anisotropy (P=0.01) and streamline count (P=0.029), and higher radial diffusivity (P=0.014) than controls in the cingulum. After correction for white matter atrophy, only fractional anisotropy and radial diffusivity remained significantly lower in AD compared to controls (P=0.003 and P=0.05). In the parahippocampal bundle, AD patients had lower mean and radial diffusivities (P=0.048 and P=0.013) compared to controls, from which only radial diffusivity survived for white matter adjustment (P=0.05). Regression models revealed that cognitive performance is also accounted for by white matter microstructural values. Structural connectivity within the DMN is important to the execution of high-complexity tasks, probably due to its relevant role in the integration of the network. (C) 2014 Elsevier Ireland Ltd. All rights reserved. (AU)

• Processo FAPESP: 11/17092-0 - Biomarcadores na Doença de Alzheimer e comprometimento cognitivo leve: estudo de métodos de ressonância magnética funcional e marcadores liquóricos e plasmáticos
• Beneficiário: Marcio Luiz Figueredo Balthazar
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 13/10431-9 - Avaliação da conectividade anatômica e funcional nas redes Default Mode e Salience na demência da Doença de Alzheimer leve e comprometimento cognitivo leve amnéstico
• Beneficiário: Marina Weiler
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto