title: Cortical changes underlying balance recovery in patients with hemiplegic stroke.
abstract: Balance problems are a major sequelae of stroke and are implicated in poor recovery of activities of daily living. In a cross-sectional study, using 50-channel event-related functional near-infrared spectroscopy we previously reported a significant correlation between individual balance ability after stroke and postural perturbation-related cortical activation in the supplementary motor area (SMA) and the prefrontal cortex. However, the neural mechanisms underlying balance recovery after stroke remain unclear. Herein, we examined the cortical involvement in balance recovery after stroke by determining longitudinal regional cortical activation changes in patients with hemiplegic stroke. Twenty patients with subcortical stroke admitted to our hospital for post-acute inpatient rehabilitation participated in this study. Before and after intensive inpatient physical and occupational therapy rehabilitation, we evaluated cortical activation associated with external postural perturbations induced by combined brisk forward and backward movement on a platform. Postural perturbation-related cortical activation in the SMA of the affected and unaffected hemispheres was significantly increased after intensive rehabilitation. The increment of the postural-perturbation-related oxygenated hemoglobin signals in the SMA of the unaffected hemisphere was significantly correlated with the gain in balance function measured by the Berg Balance Scale. These findings support the conclusion that the SMA plays an important role in postural balance control, and suggest that the SMA is a crucial area for balance recovery after hemiplegic stroke.
authors.affiliation: Department of Neurology, Graduate School of Medicine, Osaka University, Japan; Neurorehabilitation Research Institute, Morinomiya Hospital, Osaka, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Fujimoto
authors.forename: Masahito
authors.initials: M
authors.lastname: Mihara
authors.forename: Noriaki
authors.initials: N
authors.lastname: Hattori
authors.forename: Megumi
authors.initials: M
authors.lastname: Hatakenaka
authors.forename: Teiji
authors.initials: T
authors.lastname: Kawano
authors.forename: Hajime
authors.initials: H
authors.lastname: Yagura
authors.forename: Ichiro
authors.initials: I
authors.lastname: Miyai
authors.forename: Hideki
authors.initials: H
authors.lastname: Mochizuki
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D002540:Cerebral Cortex / Q000502:physiology*; D003430:Cross-Sectional Studies; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D059907:Functional Neuroimaging; D006429:Hemiplegia / Q000209:etiology / Q000534:rehabilitation*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000503:physiopathology; D004856:Postural Balance / Q000502:physiology*; D011187:Posture / Q000502:physiology; D020127:Recovery of Function / Q000502:physiology*; D019265:Spectroscopy, Near-Infrared; D000071939:Stroke Rehabilitation
keywords: ADL; BBS; Balance recovery; Berg Balance Scale; FIM; FMA; Fugl-Meyer Assessment scale; Functional Independence Measure; Functional near-infrared spectroscopy; PET; Rehabilitation; SMA; Stroke; Supplementary motor area; activities of daily living; fNIRS; functional near-infrared spectroscopy; positron emission tomography; supplementary motor area