Article

Bilaterally asymmetric stepping during walking is common to a number of
pathological gaits (e.g., hemiplegia, limping). In the present work, the
attention level of asymmetric stepping was studied by having subjects walk on a
split-belt treadmill with symmetric (2 km/h) and asymmetric (2 km/h vs 4 km/h and
2 km/h vs 6 km/h) belt speeds both with and without a dual auditory Stroop task.
There was no significant change in response reaction times across walking
conditions or between walking and standing. The proportion of stance phase was
unchanged by the dual task during symmetric walking. Stance phase proportions,
however, significantly increased during dual tasking for the limb on the faster
belt for both asymmetric conditions, while they decreased for the limb on the
slower belt for the most asymmetric condition. There were also small
modifications to double support proportions and a main effect of dual tasking to
double support proportion variability. Observed dual task changes showed
interference by the cognitive task with asymmetric gait performance, suggesting
that asymmetric stepping, such as seen in limping gaits, requires more attention
than symmetric walking. Such attention may, in part, be due to the dynamic
balance required in asymmetric limb loading and unloading.

Langue : ANGLAIS