Even after symptoms disappear, a concusson still is dangerous stuff

If you thought that once the "symptoms" of a concussion disappear, you are fine, think again. 

A new study in the Journal Neurosurgery adds further evidence of the lingering effects of the invisible injury better known as traumatic brain injury or TBI

In a study of athletes who were recovering from a concussion, the researchers found that even after there was full recovery from the symptoms of a concussion, the athletes still had difficulty processing sound.  The authors conclude that the return to play decisions that are routinely made based upon the lack of physical symptoms following a concussion needs to be reconsidered.