Introduction: American Football places considerable demands on an athlete’s skill at identifying cues and probabilistic patterns that emerge during play and requires reactions to these patterns.This ability relies on implicit learning systems in frontal-basal ganglia circuitry that form stimulus-action-outcome associations.These systems are vulnerable to neurological injury. Given the risks of football athletes to concussions and to repetitive sub-concussive head blows in a game, we expect to see differences in implicit action learning skills among football athletes compared to controls, and position specific differences based on impact exposure.
Methods: 294 National Collegiate Athletic Association Division 1 football players and 39 non-athlete student controls participated in a Action Learning task that quantified forming action-outcome associations. Participants were presented a design on a screen and instructed to selecting a left or right button in response. Upon selecting, feedback stating correct or incorrect was presented. Participants reacted to 3 different designs, which were presented randomly and several times across the task. Each design was assigned an optimal button that produced a correct outcome most of the time, and the participant’s goal was to discover the optimal response to each design.
Results: We found that Defensive Linemen as a group performed significantly worse at the task compared to controls (p=0.023).The Defensive Line is composed of two positions, Defensive tackles and Defensive ends. DTs performed worse overall at the AL task(p=0.007) compared to DEs. There were no significant differences in reaction time between the DT group and other positions.All players exhibited faster reaction times than controls (p<0.001).
Conclusions: Players in the DT position experience a high rate of head collisions compared to other positions.Data suggests that DTs respond as quickly as other athletes, but DTs are less accurate.An interpretation of this result is that it may be caused by the accumulation of head impacts over the course of their careers.
Patient Care: Repeated concussions and the subsequent diagnosis of Chronic traumatic encephalopathy is an emerging problem in medicine, therefore it is critical for physicians in the sports realm to appropriately manage athletes who are subjected to repeated head trauma. We hope that our research can help set the foundation for establishing a cognitive marker for detecting if players are accumulating head impacts that may lead to neurodegenerative disease later in their lives.
Learning Objectives: The goal of this initial study was to determine if implicit learning skills among collegiate football athletes differ from the general student population and if these skills vary by positions that are associated with high versus low rates of repetitive sub-concussive blows in game. This work would then be foundational for investigating the impact of concussions and the impact of repetitive sub-concussive blows.