Article

Studies in arm motor adaptation suggest that introducing small errors during the
adaptation period may lead to a longer retention of the aftereffect than
introducing large errors. However, it is unclear whether this notion can be
generalized to locomotor adaptation in patients with incomplete spinal cord
injury (SCI). We hypothesized that a smaller error size may lead to longer
retention of the aftereffect in patients with SCI. We recruited 12 subjects with
incomplete SCI for this study. They were instructed to walk on a treadmill while
light-, medium-, and heavy-resistance loads were applied to the right ankle to
perturb leg swing. Each of the three resistance-load conditions were specific to
the subject and determined by each subject's maximum voluntary contraction of the
hip flexors. We observed that subjects tended to make larger errors when the
resistance-load condition was greater. Following resistance load release,
subjects showed an aftereffect consisting of an increase in stride length.
Further, the aftereffect was retained longer in the medium-resistance load
condition than in the heavy- and light-resistance load conditions. This finding
suggests that a patient-specific resistance load may be needed to facilitate
retention of locomotor adaptation in patients with incomplete SCI.

Langue : ANGLAIS