A Longitudinal Evaluation of Psychophysiological and Motor Dysfunction following Concussion: Associations with Subsequent Injury - PROJECT SUMMARY: Concussions are a significant health problem, with their incidence increasing largely due to a significant rise in adolescents. While most concussions resolve within two weeks, presentation is heterogeneous, and standard clinical assessments have yet to identify a true recovery window. Psychophysiological measures have the power to elucidate lingering and subtle sensorimotor and cognitive- affective impairments. These impairments may contribute to the increased risk (~2x) of subsequent musculoskeletal (MSK) injury observed in the months following concussion. However, the underlying mechanisms of the concussion-MSK injury relationship have yet to be fully established, leaving a critical need to illuminate potential deficits. This may ultimately identify who is at risk for acute subsequent MSK injury following concussion. The long-term goal of this proposal is to simultaneously characterize the persistence of concussion-related sensorimotor and cognitive-affective deficits while laying the foundation for identifying effective, clinically feasible markers of elevated MSK injury risk following concussion. The primary objective of this NINDS R01 application is to examine the utility of psychophysiological measures for detecting lingering sensorimotor and cognitive-affective deficits following concussion. Further, we will investigate their association with future risk for subsequent acute MSK injury. The rationale behind this proposal is our preliminary data, which demonstrates a suppressed brainstem-mediated general startle (GS) response following concussion, compared to healthy athletes. This suppressed GS provides evidence of post-concussion brainstem dysfunction and may reflect the lingering sensorimotor deficits that could be driving the elevated acute MSK injury risk. Additionally, risk for injury may also be influenced by higher order brain structures that project onto the brainstem and potentiate startle (SP) in response to unpredictable, environmental threats. Our preliminary data also indicates an exaggerated SP after concussion. Given that unpredictable threats in sports often come with higher injury risk, an exaggerated response may lead to high-risk movements and behaviors. This research study will pursue three primary specific aims: to use validated NIH psychophysiological measures longitudinally to (1) examine GS as a marker for lingering sensorimotor impairment in post-concussion adolescent athletes compared to both their own premorbid GS and healthy controls, (2) examine SP during unpredictable threat as a marker for lingering cognitive-affective impairment in post-concussion adolescents compared to both their own premorbid SP and healthy controls, and (3) investigate the utility of GS and SP as moderators of the increased subsequent acute MSK injury seen following concussion. This proposal is innovative in that it will use a pre-post, longitudinal approach to elucidate psychophysiological dysfunction and risk factors for subsequent acute MSK injury following concussion. This proposal is significant as it will further aid clinicians in identifying adolescent athletes who are at increased risk of post-concussion MSK injury.
