1. Functional dedifferentiation of associative resting state networks in older adults – A longitudinal study
- Author
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Lutz Jäncke, Susan Mérillat, Brigitta Malagurski, Jessica Oschwald, Franziskus Liem, University of Zurich, and Malagurski, Brigitta
- Subjects
2805 Cognitive Neuroscience ,Male ,Longitudinal study ,Brain networks ,Rest ,Cognitive Neuroscience ,UFSP13-4 Dynamics of Healthy Aging ,050105 experimental psychology ,lcsh:RC321-571 ,03 medical and health sciences ,Cognition ,0302 clinical medicine ,Salience (neuroscience) ,Control network ,Humans ,Attention ,0501 psychology and cognitive sciences ,Longitudinal Studies ,Healthy aging ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Associative property ,Default mode network ,Aged ,Aged, 80 and over ,Brain Mapping ,Resting state fMRI ,10093 Institute of Psychology ,05 social sciences ,Brain ,Default Mode Network ,Middle Aged ,Magnetic Resonance Imaging ,Cross-Sectional Studies ,Neurology ,2808 Neurology ,Female ,Functional segregation ,150 Psychology ,Psychology ,Processing speed ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Healthy aging is associated with weaker functional connectivity within resting state brain networks and stronger functional interaction between these networks. This phenomenon has been characterized as reduced functional segregation and has been investigated mainly in cross-sectional studies. Here, we used a longitudinal dataset which consisted of four occasions of resting state fMRI and psychometric cognitive ability data, collected from a sample of healthy older adults (baseline N = 232, age range: 64-87 y, age M = 70.8 y), to investigate the functional segregation of several well-defined resting state networks encompassing the whole brain. We characterized the ratio of within-network and between-network correlations via the well-established segregation index. Our findings showed a decrease over a 4-year interval in the functional segregation of the default mode, frontoparietal control and salience ventral attention networks. In contrast, we showed an increase in the segregation of the limbic network over the same interval. More importantly, the rate of change in functional segregation of the frontoparietal control network was associated with the rate of change in processing speed. These findings support the hypothesis of functional dedifferentiation in healthy aging as well as its role in cognitive function in elderly. more...
- Published
- 2020