Article

Dual-tasking can lead to falls, as does a deterioration of obstacle avoidance
(OA) skills. Hence, it is expected that a combination of both would be even more
detrimental, especially when OA is time-critical. Previous studies confirmed this
expectation, however, due to several limitations in their design it is yet too
early to draw any definitive conclusions on the allocation of attentional
resources in OA under dual-task conditions. Therefore, attentionally demanding
primary and secondary tasks were used with the instruction to perform as well as
possible on both tasks. Nineteen healthy senior individuals (60+/-4.7 years, 8
females) performed an OA task on a treadmill while walking at 3 km/h as a single
task and combined with an auditory Stroop task.
Biceps femoris (BF) muscle
response times, OA failure rates and composite scores were used to evaluate the
data. Increased OA failure rates (3%, p=0.03) and delayed BF response times (21
ms, p<0.001) were found under dual-task conditions. Composite scores were reduced
during (p<0.001) and just after obstacle crossing (p=0.003). In conclusion,
dual-tasking during time-critical OA affects the motor as well as the cognitive
task when subjects are instructed to keep up performance on both tasks.
This adds
to the evidence indicating an increased risk of tripping or falling when
attention is divided during walking in the presence of unexpected obstacles.
CI - Copyright (c) 2012 Elsevier B.V. All rights reserved.

Langue : ANGLAIS