Article

Reactive balance recovery strategies following an unexpected loss of balance are
crucial to the prevention of falls, head trauma and other major injuries in older
adults. While a longstanding focus has been on understanding lower limb recovery
responses, the upper limbs also play a critical role. However, when a fall
occurs, little is known about the role of memory and attention shifting on the
reach to grasp recovery strategy and what factors determine the speed and
precision of this response beyond simple reaction time.
The objective of this
study was to compare response time and accuracy of a stabilizing grasp following
a balance perturbation in older adult fallers compared to non-fallers and younger
adults while loading the processing demands of non-spatial, verbal working
memory. Working memory was engaged with a progressively challenging
verb-generation task that was interrupted by an unexpected sideways platform
perturbation and a pre-instructed reach to grasp response. Results revealed that
the older adults, particularly those at high fall risk, demonstrated
significantly increased movement time to handrail contact and grasping errors
during conditions in which non-spatial memory was actively engaged. These
findings provide preliminary evidence of the cognitive deficit in attention
shifting away from an ongoing working memory task that underlies delayed and
inaccurate protective reach to grasp responses in older adult fallers.
CI - Copyright (c) 2016 Elsevier B.V. All rights reserved.

Langue : ANGLAIS