Brain injury ranges from minor and temporary to severe and permanent. Many forms of very real brain injury are not observable on formal diagnostic tests like CT scans. Forgetfulness, unusual behavior, and changes in personality can be caused by head trauma. Trained professionals like neurologists and neuropsychologists can use scientifically accepted methods to diagnose brain injuries that aren't showing up on "routine" x-ray tests. But you'll probably have to fight to get the tests paid for, and the negligent party's insurer will likely challenge the validity of the results, anyway. The Zajac & Arias Law Firm, L.L.C. has successfully represented many victims of brain injury, including multi-million dollar recoveries."