Our brains may be a bit more deserving of gentle care than most assume. According to a new study, a mild to moderate concussion may have more long-term effects on cognitive function than generally thought. These new findings have implications on how safe contact athletics really are, especially for youth.

Researchers at Newcastle and Aberdeen Universities in the U.K. compared brain images and cognition test results from people with mild concussions to those from healthy people. What they found is that the recovery of cognition, or thinking activities, takes longer than long assumed.

Concussions are injuries involving bruising of the brain when the brain is bounced off of the inside of the skull’s brain case as a result of sudden impact or jarring. Some experiences that commonly cause mild concussions include falls on ice, bicycle crashes, being in a low-speed car accident, and getting punched in the face or head during a fist fight.

The new study revealed that individuals who were tested shortly after their concussive injuries scored 25 percent lower on cognition tasks compared with healthy subjects. A year later, the test results were similar but the comparisons of brain images showed that alterations were still evident, both in terms of structure and in function.

“[I]t’s really good for people to know—those who are suffering with school performance, physical performance and even social issues—the fact that there is actual structural damage, even a year after the injury,” remarked Dr. Michael O’Brien of Boston Children’s Hospital. O’Brien is director of the Hospital’s sports concussion clinic and was not involved with the study.

The report, which is published online ahead of print this week in the journal Neurology, comes precisely when debate is heating up over the concussions suffered during this year’s World Cup play.