Soccer,

Consider the issue of second impact syndrome. There is plenty of information about NFL football players who have lifelong problems.

Issues to consider,
Does ImPACT test for physiological condition of brain recovery
or just neuropsychological performance?

Is it used to limit the school's liability from law suits?

Is it an aid to tell coaches, parents and the athlete to withhold returning to play? rather than the common need to have 5 to 7 days without a head ache as used in the past.

Historically, coaches, parents, and the player have wanted to hurry back to play for the benefit of the team and player.

A simple statistic for you. Soccer players who routinely head the ball have a 10 point lower IQ on average.

Is the ImPACT test specific enough to diagnose a drop in intelligence?

If you can find it, there are two fantastic books written by Dorothy Gronwall, Ph.D. One is expensive to buy but may be in a good main library. Mild Head Injury and Head Injury, the Facts. Dr Gronwall and Dr. Phillip Wrightson are the pioneers of the concussion industry.

Coping with Mild Traumatic Head Injury by Diane Stoler is an encyclopedia of information about the physiology and other symptoms of concussion but weak on recover therapies.

Good luck with your essay. You sound like you can grasp the information well.