Fatigue 

Fatigue is a prevalent symptom in work settings and often found in the older population. It negatively impacts the quality of life and associates with elevated mortality rates in the older population. Given that fatigue can interfere with functional activities and lead to serious consequences, special attention should be paid.

Investigating the effect of fatigue on gait balance control is crucial, as it has been related to high fall risks. Studies on standing balance have shown deterioration in the balance after fatigue, further reinforcing the impact of fatigue-induced impairments and its potential hindrances to real-life performances. However, few studies investigated the effect of fatigue on dynamic balance control during level and perturbed walking, where falls occur most often. A disturbed cognitive function is another important intrinsic factor of fall accidents. Using dual-task paradigms, researchers have shown the interaction between performance fatigability and cognitive functions.

Therefore, this project proposes to examine effects of fatigue, induced by a laboratory-based fatigue protocol and an occupational activity, on balance control, cognitive performance, and their interaction. We will validate the use of whole-body fatigue protocol, establish biomechanical parameters used to indicate fatigue-induced balance deficits, compare these parameters before and after work in older male and female workers, and lastly, seek to establish a connection between differences in parameters and mechanisms induced by the laboratory-based fatigue protocol and occupational activity. Project outcome will identify the impact of fatigue as a risk factor for movement-related accidents, form a solid basis for future studies examining how biomechanical screening and assessment may preemptively identify individuals at risk, and help develop effective interventions to prevent fatigue-related injuries.

Concussion

The purpose of this study is to examine the effects of concussion on gait stability when either a cognitive or motor perturbation is imposed. The hope for this investigation is to identify biomechanical, cognitive, and other measurements which can assist clinicians in their ability to determine whether an individual is ready to return to everyday or sport activities following concussion.

The primary questions which are being investigated currently include:
What is the cost of imposing a secondary task while walking following concussion?
How does concussion affect different age groups? Are recovery patterns similar between adolescent and adult brains?
What can computerized cognitive tests tell us about an individual’s motor performance and prevention of recurrent injury?

Attention and Gait

The main purpose of the study is to investigate the role of visuospatial attention during walking. We use obstacle avoidance as a model to examine how humans allocate and use visual information from the environment while walking, and how the body interacts with the object while planning and executing an obstacle crossing. We invent a visuospatial attention task that provides access to examine how visuospatial attention interacts with obstacle crossing during walking. In particular, by manipulating where one is paying attention in space, we are able to probe how attention and the stepping response interact. Furthermore, we apply transcranial direct current stimulation (tDCS) in several brain sites to investigate the cortical control driven by visual attention during locomotion.