Project 461382

After a mild traumatic brain injury (mTBI), or concussion, patients can suffer with symptoms such as nausea, headache, fatigue, and other changes that affect their quality of life. Changes in the brain associated with concussion are difficult to study since there is often a lot of variability between individuals in terms of how the injury is sustained, the resulting symptoms and the unpredictable occurrence of the injury. In recent years, snipers in the Canadian Special Operations Forces Command (CANSOFCOM) have presented with concussion-like symptoms after repeated exposure to impacts as a result of recoil of their weapon during training and deployment. These exposures do not result in immediate symptoms and because of this, are called sub-concussive. However, over longer periods of these exposures as their careers progress, these impacts can become symptomatic. Since the members of this military population all receive similar exposure to sub-concussive forces, this group is ideal for studying neurological health. Our proposal will evaluate a cohort of 55 military special-forces members, who are regularly exposed to significant sub-concussive impacts as they experience several rounds of training and deployment, along with 55 controls. During the study period, over four years at multiple time points, we will quantify the amount of force that each sniper is exposed to using blast sensors and modelling and relate this exposure to markers of injury in the brain and determine if there is any effect on behavior or cognitive function. We will characterize structure and physiology in the brain using MRI. Our goal is to improve detection, and monitoring of these injuries as an initial step in the development of targeted prevention and treatment strategies for all forms of mTBI.