The dangers of untreated concussions are increasingly reported in the news, but have you heard of subconcussions?  They are mild brain injuries that, over time, may result in an accumulation of damage to the brain.  Researchers from Indiana University recently published work in NeuroImage: Clinical in which they found that there are distinct differences between the brains of athletes who participate and non-contact sports and those who participate in contact sports.  They cautiously note that the differences could be normal differences that occur in brains but call for further investigation of what may be deeply concerning results.  Read a summary of the study at Science Daily:  https://www.sciencedaily.com/releases/2018/04/180405120319.htm.