Researchers are calling recent findings the tip of the iceberg.

MedPage Today reports on a paper from Brain, showing that players who suffered a single concussion playing college-level sports had “greater declines in attention and memory and a slowing of some movements more than 30 years later compared with those who never had a concussion.”

The National Football League is currently conducting its own study, looking at the long-term effects of concussions in professional football players. The preliminary findings confirm the increased risk of long-term neurological damage from concussions.

The next step, says the author, is whether there is an increased risk of Alzheimer’s dementia after suffering a concussion earlier in life.

I wouldn’t bet against it.