Evaluating military personnel with blast-related mild traumatic brain injuries, researchers have found that early symptoms of post-traumatic stress, such as anxiety, emotional numbness, flashbacks and irritability, are the strongest predictors of later disability. The results were surprising because mental health more closely correlated with disability than assessments typically made after concussions, such as tests of memory, thinking, balance, coordination and severity of headaches and dizziness, according to the study.