title: Cognitive stimulation of the default-mode network modulates functional connectivity in healthy aging.
abstract: A cognitive-stimulation tool was created to regulate functional connectivity within the brain Default-Mode Network (DMN). Computerized exercises were designed based on the hypothesis that repeated task-dependent coactivation of multiple DMN regions would translate into regulation of resting-state network connectivity. Forty seniors (mean age: 65.90 years; SD: 8.53) were recruited and assigned either to an experimental group (n=21) who received one month of intensive cognitive stimulation, or to a control group (n=19) who maintained a regime of daily-life activities explicitly focused on social interactions. An MRI protocol and a battery of neuropsychological tests were administered at baseline and at the end of the study. Changes in the DMN (measured via functional connectivity of posterior-cingulate seeds), in brain volumes, and in cognitive performance were measured with mixed models assessing group-by-timepoint interactions. Moreover, regression models were run to test gray-matter correlates of the various stimulation tasks. Significant associations were found between task performance and gray-matter volume of multiple DMN core regions. Training-dependent up-regulation of functional connectivity was found in the posterior DMN component. This interaction was driven by a pattern of increased connectivity in the training group, while little or no up-regulation was seen in the control group. Minimal changes in brain volumes were found, but there was no change in cognitive performance. The training-dependent regulation of functional connectivity within the posterior DMN component suggests that this stimulation program might exert a beneficial impact in the prevention and treatment of early AD neurodegeneration, in which this neurofunctional pathway is progressively affected by the disease.
authors.affiliation: IRCCS Fondazione Ospedale San Camillo, Venice, Italy; Department of Neuroscience, University of Sheffield, Sheffield, UK.
authors.forename: Matteo
authors.initials: M
authors.lastname: De Marco
authors.affiliation: IRCCS Fondazione Ospedale San Camillo, Venice, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Meneghello
authors.affiliation: IRCCS Fondazione Ospedale San Camillo, Venice, Italy; Department of Biomedical Sciences, Metabolic and Neuroscience, University of Modena and Reggio Emilia, Modena, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Duzzi
authors.affiliation: IRCCS Fondazione Ospedale San Camillo, Venice, Italy.
authors.forename: Jessica
authors.initials: J
authors.lastname: Rigon
authors.affiliation: IRCCS Fondazione Ospedale San Camillo, Venice, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Pilosio
authors.affiliation: IRCCS Fondazione Ospedale San Camillo, Venice, Italy; Department of Neuroscience, University of Sheffield, Sheffield, UK. Electronic address: a.venneri@sheffield.ac.uk.
authors.forename: Annalena
authors.initials: A
authors.lastname: Venneri
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology*; D001921:Brain / Q000000981:diagnostic imaging / Q000502:physiology*; D001931:Brain Mapping; D003071:Cognition / Q000502:physiology*; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D008959:Models, Neurological; D009434:Neural Pathways / Q000000981:diagnostic imaging; D009483:Neuropsychological Tests; D013663:Teaching
keywords: Alzheimer’s disease; Brain networks; Mild cognitive impairment; Resting state; fMRI