BackgroundThe ability to perform visually-guided motor tasks requires the transformation of visual information into programmed motor outputs. When the guiding visual information does not align spatially with the motor output, the brain processes rules to integrate the information for an appropriate motor response. Here, we look at how performance on such tasks is affected in young adult athletes with concussion history.MethodsParticipants displaced a cursor from a central to peripheral targets on a vertical display by sliding their finger along a touch sensitive screen in one of two spatial planes. The addition of a memory component, along with variations in cursor feedback increased task complexity across conditions.ResultsSignificant main effects between participants with concussion history and healthy controls without concussion history were observed in timing and accuracy measures. Importantly, the deficits were distinctly more pronounced for participants with concussion history compared to healthy controls, especially when the brain had to control movements having two levels of decoupling between vision and action. A discriminant analysis correctly classified athletes with a history of concussion based on task performance with an accuracy of 94 %, despite the majority of these athletes being rated asymptomatic by current standards.ConclusionsThese findings correspond to our previous work with adults at risk of developing dementia, and support the use of cognitive motor integration as an enhanced assessment tool for those who may have mild brain dysfunction. Such a task may provide a more sensitive metric of performance relevant to daily function than what is currently in use, to assist in return to play/work/learn decisions.

ObjectiveTo investigate the use of the Sport Concussion Assessment Tool 3 (SCAT3) as an assessment tool in the varsity population, as well as the effects of sex and concussion history on both baseline and postconcussion scores.MethodsA comparison between baseline and postconcussion SCAT3 scores of varsity level athletes was conducted through retrospective chart review. Differences in both baseline and postconcussion scores were further analysed by sex and history of concussion.ResultsThe only clinically significant change on the SCAT3 elicited by a concussion was that of self-reported symptoms. There were no clinically significant differences based on sex or history of concussion.ConclusionThe SCAT3 in its entirety may not be useful in this population. Additional research on sociocultural and sport aspects that may be affecting symptom reporting in this population is needed.

ObjectiveThere is a higher risk of re-injury for athletes with concussion history when returning to play, despite being asymptomatic and cleared for activity. One possible explanation is that current return to play assessments test thinking and moving separately, but sport activities often require their concurrent processing (cognitive-motor integration, CMI). The aim of this research is to characterize CMI performance across a range of ages and skill levels following concussion. We hypothesize that there will be CMI impairment, even when cognition and motor action measured separately are deemed recovered, and that impairment level is affected by age and skill level.Methods133 participants with concussion history (mix of youth, adolescent, university, and elite athletes) and 130 no-concussion controls (age/sex/skill matched) performed two eye-hand coordination tasks. Participants displaced a cursor from a central to peripheral targets by either sliding their finger on a vertically-oriented touchscreen or with decoupled eye-hand coordination (targets/cursor viewed on vertical screen but finger slid on second horizontal touchscreen with 180° cursor feedback rotation).ResultsChildren, young adult, and elite athletes with concussion history all had CMI performance deficits in movement planning, timing and execution, despite being asymptomatic and returned to play. Younger and less skilled athletes were more impaired relative to older/elite performers.ConclusionsCognitive-motor integration tasks are successful in detecting performance post-concussion relative to established assessment tools that test these domains separately. We propose that testing CMI performance, a skill crucial in sport, is important to comprehensively assess function post-concussion and to prevent re-injury.Competing interestsNone.

ObjectiveCognitive-motor integration (CMI) is required in sport when performing movements where a rule is used to align the required motor output and the guiding visual information. Previous research has shown CMI declines in young athletes with a concussion history, deemed recovered at the time of evaluation. The purpose of this study was to characterise differences in symptoms, CMI, and white matter integrity (fractional anisotropy, FA) in those with post-concussion syndrome (PCS) and healthy controls. We hypothesised that those with PCS would have decreased FA and CMI performance, with increased symptom scores.ParticipantsTwelve females were included; 6 with PCS for 6 months or more, and 6 age-matched healthy controls with no concussion history.MethodsParticipants were administered the SCAT3, four visuomotor CMI tasks, and diffusion weighted images were acquired. Participants displaced a cursor from a central target to peripheral targets by sliding their finger on a horizontally placed tablet either directly to the viewed target or with decoupled eye-hand coordination (targets viewed on a vertical monitor, 180° feedback rotation, or both).ResultsWe observed worse symptom scores and impaired performance in CMI tasks, as well as decreased mean FA in bilateral corticospinal tracts beneath the premotor and primary motor cortices and in the white matter underlying the right superior parietal lobule, in those with PCS compared to healthy controls.ConclusionsCMI decline may be related to decreased FA within the frontal-parietal-subcortical network. Measuring CMI, a skill crucial to athletes, provides an effective behavioural means for detection of brain alterations associated with concussion.Competing interestsNone.