Gazing into Thin Air: The Dual-Task Costs of Movement Planning and Execution during Adaptive Gait.
We examined the effect of increased cognitive load on visual search behavior and measures of gait performance during locomotion. Also, we investigated how personality traits, specifically the propensity to consciously control or monitor movements (trait movement 'reinvestment'), impacted the ability to maintain effective gaze under conditions of cognitive load. Healthy young adults traversed a novel adaptive walking path while performing a secondary serial subtraction task. Performance was assessed using correct responses to the cognitive task, gaze behavior, stepping accuracy, and time to complete the walking task. When walking while simultaneously carrying out the secondary serial subtraction task, participants visually fixated on task-irrelevant areas 'outside' the walking path more often and for longer durations of time, and fixated on task-relevant areas 'inside' the walkway for shorter durations. These changes were most pronounced in high-trait-reinvesters. We speculate that reinvestment-related processes placed an additional cognitive demand upon working memory. These increased task-irrelevant 'outside' fixations were accompanied by slower completion rates on the walking task and greater gross stepping errors. Findings suggest that attention is important for the maintenance of effective gaze behaviors, supporting previous claims that the maladaptive changes in visual search observed in high-risk older adults may be a consequence of inefficiencies in attentional processing. Identifying the underlying attentional processes that disrupt effective gaze behaviour during locomotion is an essential step in the development of rehabilitation, with this information allowing for the emergence of interventions that reduce the risk of falling.
Department of Life Sciences, Brunel University London, Uxbridge, United Kingdom.
Toby J
TJ
Ellmers
Department of Life Sciences, Brunel University London, Uxbridge, United Kingdom.
Adam J
AJ
Cocks
School of Psychology, Queen's University Belfast, Belfast, United Kingdom.
Michail
M
Doumas
College of Heath, University of Utah, Salt Lake City, Utah, United States of America.
A Mark
AM
Williams
Department of Life Sciences, Brunel University London, Uxbridge, United Kingdom.|Centre for Cognitive Neuroscience, College of Health and Life Sciences, Brunel University London, Uxbridge, United Kingdom.|Institute of Environment, Health and Societies, Brunel University London, Uxbridge, United Kingdom.
William R
WR
Young
D000328:Adult; D003071:Cognition / Q000502:physiology; D005260:Female; D005403:Fixation, Ocular / Q000502:physiology; D005684:Gait / Q000502:physiology*; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology*