Increasing Gait Automaticity in Older Adults by Exploiting Locomotor Adaptation

Study Summary

The investigators will test the following: 1) the extent of locomotor adaptation improvement in individuals aged 65 years and older; 2) the association between initial walking automaticity (i.e. less PFC activity while walking with a cognitive load) and prefrontal-subcortical function (measured via neuropsychological testing); and 3) whether improvements in locomotor adaptability result in improvements in the Functional Gait Assessment (FGA), a clinically relevant indicator of dynamic balance and mobility in older adults. To answer these questions, the investigators will combine innovative techniques from multiple laboratories at the University of Pittsburgh. Automatic motor control (Dr. Rosso's expertise) will be assessed by wireless functional near-infrared spectroscopy (fNIRS) of the PFC during challenged walking conditions (walking on an uneven surface and walking while reciting every other letter of the alphabet). fNIRS allows for real-time assessment of cortical activity while a participant is upright and moving by way of light-based measurements of changes in oxygenated and deoxygenated hemoglobin. Locomotor adaptation (Dr. Torres-Oviedo's expertise) will be evaluated with a split-belt walking protocol (i.e., legs moving at different speeds) that the investigators and others have used to robustly quantify motor adaptation capacity in older individuals and have shown to be reliant on cerebellar and basal ganglia function. The investigators will focus on two important aspects of locomotor adaptation that the investigators have quantified before: (Aim 1) rate at which individuals adapt to the new (split) walking environment and (Aim 2) capacity to transition between distinct walking patterns (i.e., the split-belt and the overground walking patterns), defined as motor switching. Adaptation rate and motor switching are quantified using step length asymmetry, which is the difference between a step length taken with one leg vs. the other. The investigators will focu

Primary Outcome

Adaptation is measured by the mean of the first 32 strides of in adaptation. This metric approximates the rate of learning. Higher adaptation rate means better learning rate. The adaptation rate will be measured during the visits 1 week pre-intervention, during intervention and 1 week post-intervention. The changes through the process, most importantly before and after intervention, will be calculated. Larger the change, better the learning capacity.

Conditions Studied

Interventions

• OTHER Split-belt walking
• OTHER Multiple transitions between split-belt and tied-belt walking

Study Locations (1)