Canadd/ld/adhd become a more probable concern with a series of concussion like head injuries w/ trauma. stage 3 concussions, i've had 5 in within 4yrs?

Yes: Head injuries can result in a drop in the function of your prefrontal cortex. That is the area of the brain that controls your impulses and helps attention span (the area already affected by adhd). It can also lead to word-finding and short-term memory problems, issues already present in people with adhd and ld's. Be very careful and always give your brain a rest after a head injury.