Grant: Discovery Grants Program - Individual

Maintaining upright balance is a complex skill for humans that is essential for walking, activities of daily life, and the ability to skillfully perform recreational and athletic activities. Healthy adults maintain upright balance so easily and automatically the underlying control appears deceptively simple. In reality, the challenge of maintaining upright balance requires sophisticated ongoing control from the nervous system. The long term objective of this program of research to develop new understanding that will help develop a comprehensive model of how the nervous system controls balance. The focus of this work is on balance reactions that occur when one becomes unstable. They are extremely rapid which is necessary because delays in onset and execution will increase the risk of falls and injury. In addition, in spite of the speed, the reactions are remarkably adaptable to ensure they are effective given the circumstances of the moment. To better reveal the underlying control this work addresses three main objectives: 1) determine what nervous system network serves these balance reactions 2) determine the factors that lead to such rapid reaction times, and 3) understand the influence and mechanisms of the state of the nervous system at the time of instability on balance reactions. For objective 1 we will use brain imaging and brain stimulation techniques to explore the cortical contributions to balance reactions caused by instability. For objective 2 we will explore the link between the autonomic nervous system, the excitability of the nervous system and associated reaction times. For objective 3 we will explore: 1) anticipation of potential instability and 2) the visual representation of the surrounding environment as two important factors that define reactions at the time of instability. We will use brain imaging, eye tracking and movement analysis to explore these relationships. Overall this work will build better understanding of the complex control of balance that will eventually help us understand age-related changes in balance control (among children and older adults), recovery of balance after injury and the training of skills that are dependent on dynamic stability control.