Peter Diana, Post-Gazette Steelers team physician Dr. Anthony Yates checks Ben Roethlisberger on the sideline after he was knocked out of the game against Atlanta midway through the third quarter when he took a hit to the head on a sack. Click photo for larger image.

Concussions are not new in football and other contact sports, but team doctors and athletic trainers have been getting better at recognizing the problem and intervening before more harm is done.

In Sunday's game against the Atlanta Falcons, Steelers quarterback Ben Roethlisberger lay motionless on the field for several minutes after being tackled in the third quarter. His doctors haven't said whether he suffered a concussion, but he did not return to play after the injury.

A concussion occurs when a blow to the head makes the brain shake inside the skull, explained Dr. Mark Lovell, director of the sports medicine concussion program at the University of Pittsburgh Medical Center and director of neurocognitive testing for the NFL and NHL.

Concussions don't always lead to a loss of consciousness. Symptoms can include temporary confusion, vision changes and dizziness, but the injury doesn't damage the brain's anatomy.

So, "if you do a CAT scan or an MRI, it's almost always normal," Dr. Lovell said. "It's such a tricky injury because you do not have to be knocked out. You don't have to be stumbling around on the field. You can have subtle signs of injury."

Because of federal health privacy laws, he cannot comment specifically on Roethlisberger's case. His UPMC colleague, Dr. Joseph Maroon, is the team's neurosurgeon.

Not so long ago, when athletes got knocked out they might be asked "How many fingers do you see?" before they resumed play, Dr. Lovell noted. Now, doctors and trainers on the sideline repeatedly check the injured player's level of alertness and awareness and discourage a potentially harmful return to the game.

Dr. Lovell and his colleagues have spearheaded the use of ImPACT, which stands for Immediate Postconcussion Assessment and Cognitive Testing system. It's a 20-minute computerized evaluation of the player's memory, reaction time and other parameters.

"The issue is to make sure you diagnose [concussion] properly so that you're not putting someone back out to get reinjured while they're still healing," he said. "It's used throughout almost all the high schools in the area, all the colleges, and throughout most of the NFL."

As many as 100 concussed high school athletes are assessed every week at UPMC's Center for Sports Medicine during football season. Some young football players appear to be more susceptible to concussions if they've already had three or four, Dr. Lovell said.

But, "Professional athletes tend to recover quicker ... even though they're bigger, stronger and hit harder," he noted. "It's like a natural selection process. You don't make it to the NFL if you have a real concussion problem."

There is no "concussion pill," as he put it, to treat the injury. If headaches, confusion or other neurological symptoms persist or return, seek a doctor's help. In general, concussed patients should steadily improve.

Typically, though, "What you see is that they might not feel very good for a day or two and then they start to get better," Dr. Lovell said. "Each athlete recovers at their own rate. We've found in a study we published on NFL athletes that most of them were better within a week or so."