Heading Soccer Balls Tied to Damaging Brain Changes
Doing it a lot may increase risk of memory problems in adult soccer players, study says
For the current study, Lipton and his colleagues recruited 37 adult amateur soccer players. Their ages ranged from 21 to 44 years old, and the average age was nearly 31. Twenty-eight of the volunteers were men. They played at least one competitive game of soccer each week, and practiced an average of two times a week, according to Lipton. Most had been playing since they were kids.
All underwent a special imaging technique called diffusion tensor magnetic resonance imaging that produces detailed images that show microscopic changes in the white matter of the brain.
The players also filled out a questionnaire about such factors as frequency of heading and prior concussions, and completed a number of tests to measure their thinking and memory skills.
The researchers found that there appears to be a threshold for harm from heading. Below that threshold, there wasn't as much risk, but there was significantly more risk of brain changes above it. In this study, the threshold was between 885 and 1,550 headers a year for brain changes, and higher than 1,800 headings a year for changes in memory scores.
Lipton said these findings were independent of past concussions.
"People can take some degree of trauma. Not everyone who bumps their head on a cabinet will have concussion symptoms. The question is how much does it take to have a lasting injury? And, that remains an open question, especially in children," said Lipton.
Because kids' brains are developing, they might be more susceptible to injuries, noted Lipton. But, on the other hand, he pointed out, children's brains are also quite adaptable and can recover more easily from conditions such as stroke than adult brains can.
One expert noted that the study showed that even minor insults to the brain can have lasting effects.
"This study shows that even if you don't have a concussion or a noticeable injury, if you look close enough at the brain, you can see changes. The evidence from these adults seems reasonably compelling that these minor heading events accumulate over time," said Dr. Michael Bell, director of pediatric neurocritical care at Children's Hospital of Pittsburgh.