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Salience and Default Mode Network Coupling Predicts Cognition in Aging and Parkinson’s Disease

Published online by Cambridge University Press:  18 February 2016

Deepti Putcha ,
Robert S. Ross ,
Alice Cronin-Golomb ,
Amy C. Janes  and
Chantal E. Stern
Deepti Putcha*
Affiliation:
Department of Psychological and Brain Sciences, Boston University, Boston, Massachusetts Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, Massachusetts
Robert S. Ross
Affiliation:
Department of Psychological and Brain Sciences, Boston University, Boston, Massachusetts Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, Massachusetts Department of Psychology, University of New Hampshire, Durham, New Hampshire
Alice Cronin-Golomb
Affiliation:
Department of Psychological and Brain Sciences, Boston University, Boston, Massachusetts
Amy C. Janes
Affiliation:
Brain Imaging Center, McLean Hospital, Department of Psychiatry, Harvard Medical School, Belmont, Massachusetts
Chantal E. Stern
Affiliation:
Department of Psychological and Brain Sciences, Boston University, Boston, Massachusetts Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, Massachusetts
*
Correspondence and reprint requests to: Deepti Putcha, 2 Cummington Mall, Center for Memory and Brain, Boston University, Boston, MA 02215. E-mail: [email protected]
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Abstract

Objectives: Cognitive impairment is common in Parkinson’s disease (PD). Three neurocognitive networks support efficient cognition: the salience network, the default mode network, and the central executive network. The salience network is thought to switch between activating and deactivating the default mode and central executive networks. Anti-correlated interactions between the salience and default mode networks in particular are necessary for efficient cognition. Our previous work demonstrated altered functional coupling between the neurocognitive networks in non-demented individuals with PD compared to age-matched control participants. Here, we aim to identify associations between cognition and functional coupling between these neurocognitive networks in the same group of participants. Methods: We investigated the extent to which intrinsic functional coupling among these neurocognitive networks is related to cognitive performance across three neuropsychological domains: executive functioning, psychomotor speed, and verbal memory. Twenty-four non-demented individuals with mild to moderate PD and 20 control participants were scanned at rest and evaluated on three neuropsychological domains. Results: PD participants were impaired on tests from all three domains compared to control participants. Our imaging results demonstrated that successful cognition across healthy aging and Parkinson’s disease participants was related to anti-correlated coupling between the salience and default mode networks. Individuals with poorer performance scores across groups demonstrated more positive salience network/default-mode network coupling. Conclusions: Successful cognition relies on healthy coupling between the salience and default mode networks, which may become dysfunctional in PD. These results can help inform non-pharmacological interventions (repetitive transcranial magnetic stimulation) targeting these specific networks before they become vulnerable in early stages of Parkinson’s disease. (JINS, 2016, 22, 205–215)

Keywords

Cognitive impairmentFunctional magnetic resonance imagingIntrinsic connectivity networksNeurodegenerationDefault mode networkSalience network
Type
Research Articles
Information
Journal of the International Neuropsychological Society , Volume 22 , Special Issue 2: Human Brain Connectivity in the Modern Era: Relevance to Understanding Health and Disease , February 2016 , pp. 205 - 215
Copyright
Copyright © The International Neuropsychological Society 2016 

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