title: Metabolic resting-state brain networks in health and disease.
abstract: The delineation of resting state networks (RSNs) in the human brain relies on the analysis of temporal fluctuations in functional MRI signal, representing a small fraction of total neuronal activity. Here, we used metabolic PET, which maps nonfluctuating signals related to total activity, to identify and validate reproducible RSN topographies in healthy and disease populations. In healthy subjects, the dominant (first component) metabolic RSN was topographically similar to the default mode network (DMN). In contrast, in Parkinson's disease (PD), this RSN was subordinated to an independent disease-related pattern. Network functionality was assessed by quantifying metabolic RSN expression in cerebral blood flow PET scans acquired at rest and during task performance. Consistent task-related deactivation of the "DMN-like" dominant metabolic RSN was observed in healthy subjects and early PD patients; in contrast, the subordinate RSNs were activated during task performance. Network deactivation was reduced in advanced PD; this abnormality was partially corrected by dopaminergic therapy. Time-course comparisons of DMN loss in longitudinal resting metabolic scans from PD and Alzheimer's disease subjects illustrated that significant reductions appeared later for PD, in parallel with the development of cognitive dysfunction. In contrast, in Alzheimer's disease significant reductions in network expression were already present at diagnosis, progressing over time. Metabolic imaging can directly provide useful information regarding the resting organization of the brain in health and disease.
authors: Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030.
authors: Phoebe G
authors: PG
authors: Spetsieris
authors: Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030.
authors: Ji Hyun
authors: JH
authors: Ko
authors: Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030.
authors: Chris C
authors: CC
authors: Tang
authors: Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030.
authors: Amir
authors: A
authors: Nazem
authors: Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030.
authors: Wataru
authors: W
authors: Sako
authors: Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030.
authors: Shichun
authors: S
authors: Peng
authors: Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030.
authors: Yilong
authors: Y
authors: Ma
authors: Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030.
authors: Vijay
authors: V
authors: Dhawan
authors: Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030 david1@nshs.edu.
authors: David
authors: D
authors: Eidelberg
mesh_terms: D000544:Alzheimer Disease / Q000378:metabolism / Q000503:physiopathology*; D001921:Brain / Q000378:metabolism* / Q000503:physiopathology*; D001931:Brain Mapping; D004194:Disease; D005260:Female; D006262:Health; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D009415:Nerve Net / Q000503:physiopathology*; D010300:Parkinson Disease / Q000378:metabolism / Q000503:physiopathology*; D049268:Positron-Emission Tomography; D025341:Principal Component Analysis; D012146:Rest; D013647:Task Performance and Analysis
keywords: PET; default mode network; neurodegeneration; principal component analysis; resting state networks