title: Longitudinal changes of resting-state functional connectivity during motor recovery after stroke.
abstract: OBJECTIVE
  Functional MRI (fMRI) studies could provide crucial information on the neural mechanisms of motor recovery in patients with stroke. Resting-state fMRI is applicable to patients with stroke who are not capable of proper performance of the motor task. In this study, we explored neural correlates of motor recovery in patients with stroke by investigating longitudinal changes in resting-state functional connectivity of the ipsilesional primary motor cortex (M1).
  
  
  METHODS
  A longitudinal observational study using repeated fMRI experiments was conducted in 12 patients with stroke. Resting-state fMRI data were acquired 4 times over a period of 6 months. Patients participated in the first session of fMRI shortly after onset and thereafter in subsequent sessions at 1, 3, and 6 months after onset. Resting-state functional connectivity of the ipsilesional M1 was assessed and compared with that of healthy subjects.
  
  
  RESULTS
  Compared with healthy subjects, patients demonstrated higher functional connectivity with the ipsilesional frontal and parietal cortices, bilateral thalamus, and cerebellum. Instead, functional connectivity with the contralesional M1 and occipital cortex were decreased in patients with stroke. Functional connectivity between the ipsilesional and contralesional M1 showed the most asymmetry at 1 month after onset to the ipsilesional side. Functional connectivity of the ipsilesional M1 with the contralesional thalamus, supplementary motor area, and middle frontal gyrus at onset was positively correlated with motor recovery at 6 months after stroke.
  
  
  CONCLUSIONS
  Resting-state fMRI elicited distinctive but comparable results with previous task-based fMRI, presenting complementary and practical values for use in the study of patients with stroke.
authors: Samsung Biomedical Research Institute, Department of Physical and Rehabilitation Medicine, Stroke and Cerebrovascular Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, Seoul, 135-710, Republic of Korea.
authors: Chang-hyun
authors: CH
authors: Park
authors: Won Hyuk
authors: WH
authors: Chang
authors: Suk Hoon
authors: SH
authors: Ohn
authors: Sung Tae
authors: ST
authors: Kim
authors: Oh Young
authors: OY
authors: Bang
authors: Alvaro
authors: A
authors: Pascual-Leone
authors: Yun-Hee
authors: YH
authors: Kim
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002531:Cerebellum / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D005625:Frontal Lobe / Q000503:physiopathology; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000503:physiopathology*; D010296:Parietal Lobe / Q000503:physiopathology; D020127:Recovery of Function / Q000502:physiology*; D012146:Rest / Q000502:physiology*; D020521:Stroke / Q000503:physiopathology*; D013788:Thalamus / Q000503:physiopathology; D013997:Time Factors