This JAMA article is from 2003, but it does well to expose what we are currently seen with the concussion. It is good to note that this study was with college aged individuals with a developed brain. This study did not deal with the developing brain of adolescents.
Conclusions Collegiate football players may require several days for recovery of symptoms, cognitive dysfunction, and postural instability after concussion. Further research is required to determine factors that predict variability in recovery time after concussion. Standardized measurement of postconcussive symptoms, cognitive functioning, and postural stability may enhance clinical management of athletes recovering from concussion.