The following is excerpted from an online article posted by ScienceDaily.
Experiencing three or more concussions is linked with worsened brain function in later life, according to major new research.
The study — the largest of its kind — also found having just one moderate-to-severe concussion, or traumatic brain injury (TBI), can have a long-term impact on brain function, including memory.
Led by teams at the University of Oxford and the University of Exeter, the research included data from more than 15,000 participants of the online PROTECT study, who were aged between 50 and 90 and based in the UK. They reported the severity and frequency of concussions they had experienced throughout their lives and completed annual, computerized tests for brain function.
Published in the Journal of Neurotrauma, the paper found that people who reported three or more concussions had significantly worse cognitive function, which got successively worse with each subsequent concussion after that. Attention and completion of complex tasks were particularly affected.
Lead investigator Dr. Vanessa Raymont, from the University of Oxford, said: “We know that head injuries are a major risk factor for dementia, and this large-scale study gives the greatest detail to date on a stark finding — the more times you injure your brain in life, the worse your brain function could be as you age.
“Our research indicates that people who have experienced three or more even mild episodes of concussion should be counseled on whether to continue high-risk activities. We should also encourage organizations operating in areas where head impact is more likely to consider how they can protect their athletes or employees.”
The team found that participants who reported three episodes of even mild concussion throughout their lives had significantly worse attention and ability to complete complex tasks. Those who had four or more mild concussion episodes also showed worsened processing speed and working memory. Each additional reported concussion was linked to progressively worse cognitive function.