Article

The present study examined the effects of cerebellar disease on the organization
and execution of obstacle avoidance tasks. To this end, we characterized how
variations in the execution demands of the subsequent obstacles in multiple
obstacle crossing tasks influenced the stepping performance of the initial
obstacle in patients with cerebellar degeneration (CD) by manipulating the height
(6 cm and 16 cm) and distance (1 m and 2 m) of the second obstacle. Nine patients
with bilateral cerebellar atrophy and nine age-matched normal controls were
instructed to walk along an 8 m long pathway and step over two obstacles without
contacting them. The primary finding indicated that CD patients exhibited an
elevated foot clearance over the initial obstacle when the height demand of the
second obstacle was increased. Such abnormal step-height adjustments in CD
patients are considered as an adaptive avoidance strategy to diminish the
execution demands of complex obstacle tasks and to enhance safe performance.
These results suggest that the cerebellum is important for the implementation of
optimal stepping strategies to be used during multiple obstacle crossings in
which the obstacles have different execution demands.
CI - Copyright (c) 2012 Elsevier B.V. All rights reserved.

Langue : ANGLAIS