THURSDAY, Oct. 17 (HealthDay News) -- Adding new insight to the debate over harm from football-related concussions, researchers say they see unusual activity in the brains of former National Football League players.
These traits were observed during brain scans and were most common among players whose careers were marked by frequent head injuries requiring them to leave the field.
"The NFL alumni showed some of the most pronounced abnormalities in brain activity that I have ever seen, and I have processed a lot of patient data sets in the past," study lead author Dr. Adam Hampshire, of the department of medicine at Imperial College London, in the United Kingdom, said in a college statement.
The study authors examined brain scans taken from 13 former NFL players who suspected they were having neurological problems due to injuries suffered while playing football. The men believed these neurological issues were interfering with their day-to-day activities.
Prior research has linked playing football to higher rates of brain diseases such as Alzheimer's disease and Parkinson's disease.
The study compared functional magnetic resonance imaging (fMRI) scans -- which track the brain's activity in real time -- of the players and 60 healthy volunteers after they took a test in which they were told to quickly rearrange balls in a series of tubes.
Although the healthy volunteers performed modestly better than the ex-players on the test, the scans revealed unusual activity in the frontal lobes of the players. The frontal lobe manages higher-level brain activity known as "executive function."
"The critical fact is that the level of brain abnormality correlates strongly with the measure of head impacts of great enough severity to warrant being taken out of play," Hampshire said. "This means that it is highly likely that damage caused by blows to the head accumulate toward an executive impairment in later life."
The researchers believe that brain scans could help physicians reveal neurological problems in football players that aren't otherwise obvious to observers.
"Researchers have put a lot of time into developing tests to pick up on executive dysfunction, but none of them work at all well," Hampshire said. "It's not unusual for an individual who has had a blow to the head to perform relatively well on a neuropsychological testing battery, and then go on to struggle in everyday life."
He also called for more research. "This is a relatively preliminary study," he said. "We really need to test more players and to track players across seasons using brain imaging."
The study was published Oct. 17 in the journal Scientific Reports.
There's more on concussions at the U.S. National Library of Medicine.