Posted by Brigham and Women's Hospital January 16, 2013
Soccer, popular throughout the world, is the only sport where the unprotected head is a primary point of contact for the ball during play. While such contact, known as “heading,” may not cause the traumatic brain injury seen in other contact sports, the effect of repeated, minor blows to the head is unclear. (These minor blows to the head are call sub-concussive, meaning that they are not strong enough to result in a concussion.) Newly published research, conducted by scientists at Brigham and Women’s Hospital (BWH) and Ludwig-Maximilians-University in Munich, Germany, may help shed light on whether sub-concussive blows can cause brain injury among soccer players and other athletes.
Using a high-resolution magnetic resonance imaging (MRI) technique called diffusion tensor imaging, the researchers studied the brains of 12 male soccer players from elite soccer clubs in Germany and compared their MRI scans to eight competitive swimmers, a sport with few head injuries. Study participants in both groups were similar in age and gender. The researchers specifically looked for changes in the white matter areas of the brain. The white matter regions are known to be responsible for attention, visual processing, higher order thinking, and memory.
“Our study found differences in integrity of the white matter of the brains of soccer players compared with swimmers,” said Inga Katharina Koerte, MD, lead author and a neuroradiologist in the Psychiatric Neuroimaging Laboratory at BWH. “Although only participants without previous symptomatic self-reported concussion or physician diagnosed concussion were included, we found changes in the brain that are consistent with findings observed in patients with mild traumatic brain injury.”
While the researchers observed clear differences in the brain structure between soccer players and swimmers, the reason for these differences is still not clear. Martha Shenton, PhD, senior author and a researcher at BWH and the VA Boston Healthcare System observed that blows to the head from the soccer ball may be one reason, though she notes that other factors, such as incidental contact resulting during normal soccer play or even lifestyle behaviors could contribute. “Additional research is needed to confirm these results we observed in this small sample of soccer players and to help clarify the effects that alterations of white matter have on behavior and health.