Cognitive-motor integration deficits in young adult athletes following concussion

Abstract

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.

A History of Concussion Does Not Lead to an Increase in Ocular Near Point of Convergence

“…A history of previous concussion has been shown to alter a variety of behavioral, structural, and functional measurements in young adults. Behaviorally, changes have been demonstrated in reaching movements requiring complex visuomotor transformations [5], measurements of executive function and processing speed [9], tests of attention and concentration [38], and tasks probing verbal fluency function [34]. The functional alterations associated with a history of concussion may be related to corresponding changes occurring in brain structure and physiology [7,11,12,34,41,51].…”

Development of rule-based eye-hand-decoupling in children and adolescents

“…This finding suggests that including a feedback reversal in addition to a plane change in the current study may have increased the sensitivity of our measures to detect age-related differences. A future study including a plane change only condition and a feedback reversal only condition (Brown et al, 2015; could be helpful in elucidating the interplay between these different levels of visual-motor dissociation and developmental changes.…”

“…One might argue that the first half of this U-shaped function comprises the results presented here, at least for movement planning (cf., Figure 2(a)). The eye-hand-decoupled task in combination with the direct interaction task used in the present study has been proven to be an effective and sensitive assessment tool in detecting performance declines in neurological disorder populations, e.g., in participants with high Alzheimer's risk, mild cognitive impairment, and a history of concussion (Brown et al, 2015;Salek et al, 2011). Therefore, the present task might be able to provide timely knowledge about potential developmental delays and dysfunction and issues related to complex eye-hand coordination performance in youth populations (Piek et al, 2006).…”

“…All participants performed two visuomotor transformation tasks, similar to those previously used in eye-hand-decoupled studies of adult and elderly populations (Brown et al, 2015;. Participants sat on a chair at a desk where the experimental task was presented on an Acer Iconia 6120 dual-touchscreen laptop, with a touch screen (14ʹ LCD display, 1366 × 768 pixel resolution) in the vertical plane and one in the horizontal plane (i.e., where a keyboard would usually be found).…”

“…Eye-hand-decoupling is crucial for many every day and sport-related activities (Brown, Dalecki, Hughes, Macpherson, & Sergio, 2015). Thus, the development of eyehand-decoupling in childhood or adolescence provides an important foundation for complex rule-based eye-hand coordination later on in life that goes beyond fundamental motor functions such as direct grasping, reaching, walking and running (Lubans et al, 2010).…”