Article

The purpose of this study was to investigate the effects of cognitive and
visuomotor tasks on gait control in terms of the magnitude and temporal structure
of the variability in stride time and lower-limb kinematics measured using
inertial sensors. Fourteen healthy young subjects walked on a treadmill for 15min
at a self-selected gait speed in the three conditions: normal walking without a
concurrent task; walking while performing a cognitive task; and walking while
performing a visuomotor task. The time series data of stride time and peak shank
angular velocity were generated from acceleration and angular velocity data
recorded from both shanks. The mean, coefficient of variation, and fractal
scaling exponent alpha of the time series of these variables and the standard
deviation of shank angular velocity over the entire stride cycle were calculated.
The cognitive task had an effect on long-range correlations in stride time but
not on lower-limb kinematics. The temporal structure of variability in stride
time became more random in the cognitive task. The visuomotor task had an effect
on lower-limb kinematics. Subjects controlled their swing limb with greater
variability and had a more complex adaptive lower-limb movement pattern in the
visuomotor task. The effects of the dual tasks on gait control were different for
stride time and lower-limb kinematics. These findings suggest that the temporal
structure of variability and lower-limb kinematics are useful parameters to
detect a change in gait pattern and provide further insight into gait control.
CI - Copyright (c) 2016 Elsevier B.V. All rights reserved.

Langue : ANGLAIS