Locomotion supraspinal control assessment in healthy people and stroke patients with the use of passive motor fMRI paradigm

Abstract

Functional magnetic resonance imaging (fMRI) is widelyapplicable for sensorimotor cortex mapping in human. Themost challenging fMRI task for researchers is the assessment oflocomotion. The aim of our study was to design of a passivemotor fMRI paradigm for assess supraspinal control of the skillof walking in normal subjects and in patients with motor neurologicdeficit after ischemic stroke. We conducted fMRI intwo groups of human subjects: first group 19 healthy subjects(10 females and 9 males, mean age = 38 [31,5; 60] years), secondgroup 18 ischemic stroke patients in early recovery period(first 6 months) (6 females, 12 males, mean age = 55,5[45,5; 64,5] years) with severe and moderate (mean Fugl-Meyer scale score = 22 [15; 28]).The protocol consisted ofblocked-design paradigm: plantar stimulation by imitation ofslow walking vs rest. Individual and group activation patternswere analyzed using statistical package SPM5. A significantactivation (pcorrect0.05 at cluster level) in first group wasobserved in the primary and secondary sensorimotor cortex,premotor and dorsolateral prefrontal cortex, in insula. Due tolesion localization second group was subdivided into corticalsubcotrical(CS) and subcortical (S) subgroups. In CS subgroupthere was reduce of activation size, more prominent inthe affected hemisphere, whereas in S subgroup the extensionof activation regions in both hemispheres was revealed, comparingto group 1. It was demonstrated that our passive motorfMRI paradigm of walking imitation with the use of plantarload imitator Korvit can be used to localize the ensorimotorbrain areas involved in locomotion in both healthy people andpatients. Concerning stroke patients, such an approach canhelp in understanding the mechanisms of supraspinal controlof the skill walking and optimal rehabilitation strategy.

Keywords

• fmri
• paradigm
• locomotion
• stroke