Abstract: ObjectiveTo measure cortical areas involved ankle dorsiflexion and planter flexion.MethodsSix-health subjects performed ankle dorsiflexion and planter flexion. While, functional MRI at 1.5 T was made.ResultsWhen ankle dorsiflexion, the excited cortical areas included bilateral primary motor cortex (MⅠ) and primary somatosensory cortex (SⅠ), but area on contralateral side bigger than that on ipsilateral side, as well as chief visual cortexes and vermis of cerebellum. Inhibited areas included area 19, area 20 and area 39. When ankle planter flexion, the excited areas included contralateral secondary motor area (MⅡ) and striate body, ipsilateral supplementary motor area (SMA) and limbic system. Inhibited areas included bilateral upper middle precentral gyrus and postcentral gyrus, superior parietal lobule, inferior parietal lobule and prefrontal cortex.ConclusionThere is a great difference in the brain function images respectively in ankle dorsiflexion and planter flexion.

Key words: ankle, functional magnetic resonance imaging (fMRI), rehabilitation, brain function, hemiplegia, pyramidal tract