A new study suggests that a history of concussion involving at least a momentary loss of consciousness may be related to the buildup of Alzheimer’s-associated plaques in the brain. The research is published in the Dec. 26, 2013, online issue of Neurology®, the medical journal of the American Academy of Neurology. “Interestingly, in people with a history of concussion, a difference in the amount of brain plaques was found only in those with memory and thinking problems, not in those who were cognitively normal,” says study author Michelle Mielke, Ph.D., a Mayo Clinic researcher.