title: Parkinson's disease: increased motor network activity in the absence of movement.
abstract: We used a network approach to assess systems-level abnormalities in motor activation in humans with Parkinson's disease (PD). This was done by measuring the expression of the normal movement-related activation pattern (NMRP), a previously validated activation network deployed by healthy subjects during motor performance. In this study, NMRP expression was prospectively quantified in (15)O-water PET scans from a PD patient cohort comprised of a longitudinal early-stage group (n = 12) scanned at baseline and at two or three follow-up visits two years apart, and a moderately advanced group scanned on and off treatment with either subthalamic nucleus deep brain stimulation (n = 14) or intravenous levodopa infusion (n = 14). For each subject and condition, we measured NMRP expression during both movement and rest. Resting expression of the abnormal PD-related metabolic covariance pattern was likewise determined in the same subjects. NMRP expression was abnormally elevated (p < 0.001) in PD patients scanned in the nonmovement rest state. By contrast, network activity measured during movement did not differ from normal (p = 0.34). In the longitudinal cohort, abnormal increases in resting NMRP expression were evident at the earliest clinical stages (p < 0.05), which progressed significantly over time (p = 0.003). Analogous network changes were present at baseline in the treatment cohort (p = 0.001). These abnormalities improved with subthalamic nucleus stimulation (p < 0.005) but not levodopa (p = 0.25). In both cohorts, the changes in NMRP expression that were observed did not correlate with concurrent PD-related metabolic covariance pattern measurements (p > 0.22). Thus, the resting state in PD is characterized by changes in the activity of normal as well as pathological brain networks.
authors: Center for Neurosciences, Feinstein Institute for Medical Research, Manhasset, New York 11030, USA.
authors: Ji Hyun
authors: JH
authors: Ko
authors: Hideo
authors: H
authors: Mure
authors: Chris C
authors: CC
authors: Tang
authors: Yilong
authors: Y
authors: Ma
authors: Vijay
authors: V
authors: Dhawan
authors: Phoebe
authors: P
authors: Spetsieris
authors: David
authors: D
authors: Eidelberg
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000627:therapeutic use; D001921:Brain / Q000000981:diagnostic imaging / Q000187:drug effects / Q000503:physiopathology*; D001931:Brain Mapping; D002560:Cerebrovascular Circulation; D015331:Cohort Studies; D046690:Deep Brain Stimulation / Q000379:methods*; D017666:Deuterium Oxide; D005260:Female; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology*; D009434:Neural Pathways / Q000187:drug effects / Q000502:physiology; D010300:Parkinson Disease / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology* / Q000628:therapy; D049268:Positron-Emission Tomography; D020531:Subthalamic Nucleus / Q000502:physiology
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa; D017666:Deuterium Oxide