Each year, over 150,000 sports- and recreation-related traumatic brain injuries (TBIs), including concussions, are treated in children under 19 years old (Gilchrist, Thomas, Xu, McGuire, & Coronado, 2011). Children and adolescents have an increased risk for such injuries, with increased severity and prolonged recovery. Even a relatively minor head trauma can result in physical, cognitive, behavioral, and social consequences (Laforce & Martin-MacLeod, 2001).  The cognitive and behavioral symptoms generally dissipate with time, such that it is commonly accepted that individuals fully recover all cognitive function (for review,seeCarroll et al., 2004).  However, people who experience repeated closed head injuries over time, such as professional boxers and football players, may develop severe cognitive deficits as a result of cumulative trauma (McKee et al., 2009; Uryu et al., 2002).  Yet these two observations appear to conflict.  How can a person completely recover from each injury, yet still experience a severe deficit after multiple injuries?  One possible explanation is that the available and widely used tools for assessment are not sufficiently sensitive to capture gradual cognitive changes from mild injuries that aggregate over time.  The current studies investigate whether subtle measures of language processing might provide a better indicator of the effects of concussion in teenagers, and seek to create a language-based assessment that could be used to identify concussion in still younger children.