A study of the brains of 40 retired NFL players has found evidence that damage and impairment is widespread in those who have played the game professionally.
The study is small, but nonetheless one of the largest to examine the brains of former players while they're alive. The new research, to be presented today at the annual meeting of the American Academy of Neurology, looked at the retired players, most for less than five years, with an average age of 36.
Even among such young retirees, researchers from Florida State University's School of Medicine found that 43 percent, or 17 of the former players, had structural abnormalities in the connective tissue of their brains — the white matter that speeds signals among cells — that is considered reliable evidence of traumatic brain injury. Brain scans showed that 30 percent, or 12, had disruption of the nerve axons — the protuberances that extend from one brain cell to another to transmit electrical impulses — consistent with brain injury.
And in tests of cognitive performance, roughly half of the former players showed significant problems of executive function — a measure of a person's ability to maintain attention, plan and organize. Specifically, 45 percent had measurable problems with learning and memory, 42 percent had problems with attention and concentration, and 24 percent had problems with spatial and perceptual function.
The retired players ranged in age from 27 to 56, and had played in the NFL anywhere from two to 17 years. (The average was seven years.) The study's lead author, FSU's Dr. Francis X. Conidi, called it "one of the largest studies to date in living retired NFL players and one of the first to demonstrate significant objective evidence for traumatic brain injury in these former players."
There was no control group, which would give experts a clear basis for comparison among similar-aged men who had not engaged in contact sports. And it was not clear how the study's participants were recruited, and whether they had sought treatment for neurological problems in advance of their recruitment into the study. Those factors, in addition to the study's relatively small size, make it difficult to drawer larger conclusions.