A Functional MRI Study of Subjects Recovered From Hemiparetic Stroke

TLDR: Recovered finger-tapping by stroke subjects activated the same motor regions as controls but to a larger extent, particularly in the unaffected hemisphere, which indicates increased reliance on these motor areas may represent an important component of motor recovery.

Abstract: Background and Purpose Stroke recovery mechanisms remain incompletely understood, particularly for subjects with cortical stroke, in whom limited data are available. We used functional magnetic resonance imaging to compare brain activations in normal controls and subjects who recovered from hemiparetic stroke. Methods Functional magnetic resonance imaging was performed in ten stroke subjects with good recovery, five with deep, and five with cortical infarcts. Brain activation was achieved by index finger-tapping. Statistical parametric activation maps were obtained using a t test and a threshold of P<.001. In five bilateral motor regions, the volume of activated brain for each stroke subject was compared with the distribution of activation volumes among nine controls. Results Control subjects activated several motor regions. During recovered hand finger-tapping, stroke subjects activated the same regions as controls, often in a larger brain volume. In the unaffected hemisphere, sensorimotor cortex activat...