title: Decreased Default Mode Network connectivity correlates with age-associated structural and cognitive changes.
abstract: Ageing entails cognitive and motor decline as well as brain changes such as loss of gray (GM) and white matter (WM) integrity, neurovascular and functional connectivity alterations. Regarding connectivity, reduced resting-state fMRI connectivity between anterior and posterior nodes of the Default Mode Network (DMN) relates to cognitive function and has been postulated to be a hallmark of ageing. However, the relationship between age-related connectivity changes and other neuroimaging-based measures in ageing is fragmentarily investigated. In a sample of 116 healthy elders we aimed to study the relationship between antero-posterior DMN connectivity and measures of WM integrity, GM integrity and cerebral blood flow (CBF), assessed with an arterial spin labeling sequence. First, we replicated previous findings demonstrating DMN connectivity decreases in ageing and an association between antero-posterior DMN connectivity and memory scores. The results showed that the functional connectivity between posterior midline structures and the medial prefrontal cortex was related to measures of WM and GM integrity but not to CBF. Gray and WM correlates of anterio-posterior DMN connectivity included, but were not limited to, DMN areas and cingulum bundle. These results resembled patterns of age-related vulnerability which was studied by comparing the correlates of antero-posterior DMN with age-effect maps. These age-effect maps were obtained after performing an independent analysis with a second sample including both young and old subjects. We argue that antero-posterior connectivity might be a sensitive measure of brain ageing over the brain. By using a comprehensive approach, the results provide valuable knowledge that may shed further light on DMN connectivity dysfunctions in ageing.
authors.affiliation: Departament de Psiquiatria i Psicobiologica Clinica, Facultat de Medicina, Universitat de Barcelona Barcelona, Spain.
authors.forename: Didac
authors.initials: D
authors.lastname: Vidal-Piñeiro
authors.affiliation: Unitat de Lípids, Servei Endicronologia i Nutrició, Hospital Clínic Barcelona, Spain.
authors.forename: Cinta
authors.initials: C
authors.lastname: Valls-Pedret
authors.affiliation: Departament de Psiquiatria i Psicobiologica Clinica, Facultat de Medicina, Universitat de Barcelona Barcelona, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Fernández-Cabello
authors.affiliation: Departament de Psiquiatria i Psicobiologica Clinica, Facultat de Medicina, Universitat de Barcelona Barcelona, Spain ; Laboratoire de neuropsychologie, INSERM U1077 Caen, France.
authors.forename: Eider M
authors.initials: EM
authors.lastname: Arenaza-Urquijo
authors.affiliation: Departament de Psiquiatria i Psicobiologica Clinica, Facultat de Medicina, Universitat de Barcelona Barcelona, Spain ; Institut d'Investigacions Biomédiques August Pi i Sunyer (IDIBAPS) Barcelona, Spain.
authors.forename: Roser
authors.initials: R
authors.lastname: Sala-Llonch
authors.affiliation: Departament de Psiquiatria i Psicobiologica Clinica, Facultat de Medicina, Universitat de Barcelona Barcelona, Spain.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Solana
authors.affiliation: Institut d'Investigacions Biomédiques August Pi i Sunyer (IDIBAPS) Barcelona, Spain ; Servei de Radiologia, Hospital Clínic de Barcelona Barcelona, Spain.
authors.forename: Núria
authors.initials: N
authors.lastname: Bargalló
authors.affiliation: Departament de Psiquiatria i Psicobiologica Clinica, Facultat de Medicina, Universitat de Barcelona Barcelona, Spain ; Institut d'Investigacions Biomédiques August Pi i Sunyer (IDIBAPS) Barcelona, Spain.
authors.forename: Carme
authors.initials: C
authors.lastname: Junqué
authors.affiliation: Unitat de Lípids, Servei Endicronologia i Nutrició, Hospital Clínic Barcelona, Spain.
authors.forename: Emilio
authors.initials: E
authors.lastname: Ros
authors.affiliation: Departament de Psiquiatria i Psicobiologica Clinica, Facultat de Medicina, Universitat de Barcelona Barcelona, Spain ; Institut d'Investigacions Biomédiques August Pi i Sunyer (IDIBAPS) Barcelona, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Bartrés-Faz
keywords: Default Mode Network; aging; arterial spin labeling; connectivity; gray matter; memory; resting-state fmri; white matter