Explaining the NFL's latest concussion controversy and policy change

It's a serious problem. TBI can result from multiple or severe concussions...also a risk for Parkinson's

PO1 William "Chip" Nagel
..."The other major variable is around-the-clock access to medical care. "They have certified athletic trainers, they have doctors, they have physical therapists who are monitoring them and progressing them through the protocol at an appropriate rate," he said.

Returning to the field too soon after a concussion can be dangerous. Research has shown that people who experience a concussion are more likely to have a future concussion, and some studies of people with multiple concussions have found that the subsequent injuries can cause worse symptoms.

While medical professionals have made major strides in identifying concussions, diagnosis can still be a challenge, D'Lauro added. There is no single test that can unequivocally identify concussions, unlike infections like strep throat. "You go take your kids to the pediatrician, and they do the rapid strep [test], it's like — you're good or you're not," he said. "There's nothing like that for concussions. It's all clinician judgment, so it is pretty hard."

Research shows that even a single concussion is associated with an increased risk of brain disorders like Parkinson's disease and dementia.

And research shows that repeated hits to the head — not just concussions – can increase the risk of developing the degenerative brain condition CTE, which has been found in many former NFL players."