A study involving 30 children (aged 8-10), of whom 15 had experienced a sports-related concussion two years earlier, and all of whom were athletically active, found that those with a history of concussion performed worse on tests of working memory, attention and impulse control, compared to the controls. This impaired performance was also reflected in differences in brain activity. Additionally, those who were injured at a younger age had the largest cognitive deficits.
All of this points to a need for focused and perhaps prolonged interventions, especially for younger children.
(2016). The persistent influence of concussion on attention, executive control and neuroelectric function in preadolescent children.
International Journal of Psychophysiology. 99, 85 - 95.