A study published in the Journal of Head Trauma Rehabilitation analyzed results from almost 400 high school and college football players during the 2008-2009 playing season in Milwaukee, WI. A total of 28 players sustained concussions during the playing season. and were monitored using Quantitative EEG (qEEG) recording, balanced & body control systems, and cognitive testing.

The qEEG results showed that abnormal readings in the concussed players continued long after more traditional tests (balance testing and cognitive testing) for concussions came back "clean," These results point to more evidence that there is a "recovery window" in the brain as it heals from a concussion that might be significantly longer than most athletic trainers and physicians have traditionally assumed.

Here is a link to the abstract: http://journals.lww.com/headtraumare...Related.6.aspx