We continue our special look at athletes and injuries. Doctors say they're seeing an increase in concussions involving high school athletes. FOX17's Eric Alvarez and Erika Kurre join us with an EXCLUSIVE look at one woman's struggle to cope with the long term effects. Doctors say concussions can affect a person's ability to process and remember information. The good news though: a single concussion usually doesn't have long-term symptoms. Doctors say multiple concussions can have severe and irreversible effects, and that's why they want to find better ways to diagnose them. Tonight we meet 2 doctors and a former athlete on a mission to make changes. Every time 2 football players collide, there's a risk of a concussion.

"A concussion is a brain injury, there is no structural injury, so you don't see a tear of blood or anything like that if you do a CAT scan or an MRI," says Vanderbilt Concussion Center's Dr. Andrew Gregory. "What it does, it affects the ability of the nerves in the brain to communicate back and forth, and so processing is affected."

"What the doctor had told me about 10 years ago was that I should never get another concussion, that the way the fluid was around my brain, that if I got another one that I could possibly die," says Barkley.

Barkley has suffered close to 20 concussions in her lifetime, but now doctors tell her the damage may be irreversible.

"What they let us know is that I have a 98% chance of getting early onset Alzheimer's," says Barkley.

Barkley is only 38 years old but says she's already losing tracks of time, with growing gaps in her short-term memory.

"It scares me for my children," says Barkley. "I just have this image that keeps popping into my mind of one of my children, you know, getting ready for prom and people telling me to take pictures or to be in a picture and me not to know why. Not to know who the person is."

So how do concussions happen? A Brentwood Academy kick returner runs a 40-yard dash in 4.5 seconds reaching a top speed of about 18mph. The guy trying to bring him down also has a top speed of 18mph, which means if both players break clean through the pack, heads can collide at 36mph, causing severe deceleration and movement of the brain.

"They're faster and they're bigger and so when they collide it's a more severe collision," says Sports Radio Host and Football Gear Distributor to schools all across the state Tate Mathews.

Mathews says newer helmets with redesigned shells help reduce concussions by allowing head to head collisions to glance to the side instead of absorbing the impact head on.

"This is something that's important and we need to get the kids in the most up to date helments that they can and the good thing is the administrators, the principals and the headmasters, they're more willing to release the funds to purchase new helments now than they used to be because they understand the importance of it," says Mathews.

Dr. Gregory says even the most cutting edge technology can't stop them altogether.

"Doesn't matter how good we get the helmet, it will not prevent concussion and the reason is concussion really shaking up the brain, which the helmet doesn't prevent," says Dr. Gregory. "What helmets do prevent is they prevent skull damage."

So it's important to know how to diagnose them and keep players off the field until their symptoms are completely gone. That's why Vancerbilt Medical Center launched its Sports Concussion Center last summer and tested thousands of student athletes before the season started.

"The point of doing the preseason testing is to have what is called a baseline so you know what their neuropsych testing looks like before they're injured so if they're then injured you can compare it back to their pre-injury baseline," says Dr. Gregory.

Dr. Gregory says the tests aren't fool proof, and a player that really wants back in the game could lie about the symptoms. Barkley draws on personal experience when she says it's better to play it safe.

"If you have any of those symptoms, that means you still need to lay off, your brain is probably still a little swollen and you can get a concussion with the next hit," says Barkley.

Doctors at the Vanderbilt Concussion Center say many high school football coaches are being trained to recognize concussions but also urge parents of student athletes to continue monitoring after the final whistle blows. Doctors say parents should be on alert for severe confusion, headaches, vision problems, persistent vomiting, numbness in the arms or legs and difficulty waking the athlete. We have additional information on these special reports here on our website. Just click on FOX LINKS.Concussions