Most daily movements involve some form of decision making under risk. For example, people do not reach as far on an elevated platform compared to level ground. Indeed, there are many behavioral examples of such risk-sensitive movement control even when the dynamics remain the same. Despite these widely observed risk-sensitive phenomena, there have been no quantitative descriptions of the underlying movement decision processes. This project aims to fill this gap, and develop dynamical models to identify the subjective costs and rationales underlying whole-body movement under risk. Movements will be analyzed under the framework of statistical decision-making under conditions of risk. Subjects will perform whole-body movements in conditions of varying postural threat. The behavioral changes observed between these conditions, in conjunction with model predictions, will be used to infer the subjective risk-sensitivity associated with the increased postural threat. This approach will inform the analysis of risk-, variability- and age-related changes in functional performance, and provide insights about the mechanisms underlying risk-seeking and risk-averse behavior in a variety of movements.
This project is expected to advance knowledge and understanding in the general area of neuromuscular dynamics and decision-making under risk; that is, how our central nervous system weighs risks and rewards when moving our bodies. Although great achievements in neuroscience have helped us to understand how our nervous system controls our movements, relatively little is known about how our sense of risk, especially as we age, influences these movements. An understanding of the effect of risk and variability on balance and falls can direct future research targeting injury prevention, identification of those at risk for falls, and the design of interventions.
