Grant: Discovery Grants Program - Individual

This ongoing research program will provide a better understanding of how sensory information about contact with the environment is realized and utilized into functional balance reactions during locomotion. The long term objectives include substantial contributions to the understanding of the mechanisms of plantar-surface sensation use within human movement and also to inform the design of footwear, flooring and walking aids that involve, either directly or indirectly, plantar-surface sensation. The short term objectives of this proposal are 1) to determine the effects of reduced foot sensation states upon plantar pressure changes, the associated generation of lower limb muscle activity and joint moment/movement production during perturbed gait; 2) to determine the effect of facilitating plantar-surface sensation on plantar-pressure, the associated generation of lower limb muscle activity and joint moment/movement production during perturbed gait and 3) to model the mechanism of sensation/input of plantar pressure to functional responses using data from the two aforementioned objectives and data previously collected for the existing NSERC Discovery grant. Using synchronized measurement of pressure, force, motion and electromyographical data will investigate the effects of the loss of foot sensation and the potential for facilitation of foot sensation on dynamic balance during gait perturbations. The use of individual pressure measurement, electromyography and inverse dynamics to associate pressure to functional output (joint moments/movements) will greatly enhance the understanding of how contact pressure is utilized by the central nervous system. Secondly, the use of plantar-surface reduction/facilitation methods will permit identification of changes, due to reduction/facilitation in plantar-surface sensation, in muscular activity that produces functional balance reactions (joint moments/movements) to perturbations. These synchronized measurements of plantar pressure, muscle activity and joint kinetics will provide insight into how the CNS utilizes plantar-surface sensation information. These results will be used as the basis for potential interventions (facilitation insoles, predictive modeling (objective #3), footwear, flooring, etc.) to address the problem of falls in older adults (age-related) and patient populations (disease-related) due to their foot insensitivity.