Abstract
The ability to maintain balance is critical for daily activities such as walking and fall avoidance. The contemporary models of postural control emphasize the central and somatic interactions engaged in maintaining balance; however, there is emerging evidence that the autonomic nervous system (ANS) – the sympathetic division, in particular – routinely participates in postural control. The purpose of this paper is to review the evidence demonstrating the autonomic interactions in postural control. These interactions are presented in two broad categories: those that conceptualize the maintenance of postural equilibrium as a component of bodily homeostasis and those that illustrate how changes in affective states link cognitive perceptions and physiological responses (in this case, balance). The shared commonalities between postural and autonomic pathways are presented, pointing to the areas of overlap and the potential sources of the interaction. Although the specific function of autonomic engagement in postural control remains unknown, the potential roles are explored and highlight the directions for continued study.
About the authors
Kathryn Sibley is a Post-Doctoral Fellow at the Toronto Rehabilitation Institute – University Health Network, and holds a Lecturer appointment in the Department of Physical Therapy at the University of Toronto. She completed her graduate training in Rehabilitation and Medical Sciences at the University of Toronto. Her goal is to optimize the health of older adults and people living with chronic conditions by preventing falls, with a focus on one key risk factor: balance. Her unique approach emphasizes increasing understanding of the physiological systems engaged in postural control and the impact of impairment on fall risk, and on increasing the efficacy and uptake of evidence-based interventions into health promotion and care practices.
George Mochizuki earned his PhD in Neuroscience from the University of Western Ontario in 2006. Since completing his postdoctoral training at the Toronto Rehabilitation Institute in 2009, he has been a Scientist with the Heart and Stroke Foundation Canadian Partnership for Stroke Recovery and the Brain Sciences Research Program at the Sunnybrook Research Institute. He is also an Assistant Professor in the Department of Physical Therapy at the University of Toronto. His research focuses on better understanding the contributions of the central nervous system on anticipatory and reactive balance control in healthy individuals and in the post-stroke population.
Bimal Lakhani is a post-doctoral fellow in the Department of Physical Therapy at the University of British Columbia. He completed his MSc and PhD at the University of Toronto in the Department of Rehabilitation Science. His graduate work investigated the central nervous system processes involved in the generation of rapid corrective balance recovery movements, which are typically impaired following stroke. Dr. Lakhani’s research interests are focused on improving the overall quality of life of stroke survivors by understanding the specific mechanisms that result in mobility and motor control limitations and by developing novel rehabilitation strategies that target those limitations.
William E. McIlroy received a doctorate, with specialization in neurophysiology, from the University of Guelph in 1991. He is currently Professor and Chair in the Department of Kinesiology, Faculty of Health Sciences, University of Waterloo. Dr. McIlroy is also a Senior Scientist at Sunnybrook Health Sciences Centre and the Toronto Rehabilitation Institute. His research involves developing understanding of the control of balance and mobility to lead to new treatments and technologies to maximize mobility and minimize the risk of falling among older adults and those with neurologic injury.
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