A new study found concussions that cause one to lose consciousness could be linked to Alzheimer's down the road.

A research team found serious concussions could lead to a buildup of "Alzheimer's-associated" plaque in the brain, an American Academy of Neurology news release reported.

"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," study author Michelle Mielke, PhD, with Mayo Clinic, said in the news release.

Researchers performed brain scans on 448 people who had no sign of memory problems and 141 individuals struggling with mild cognitive impairment. All of the participants were over the age of 70; the researchers recorded whether or not the study subjects had ever received a serious head injury.

About 17 percent of the participants with no thinking or memory problems had suffered a brain injury, 18 percent of those with memory problems had sustained one.

The researchers did not find a difference in brain scan measurements between the participants without memory problems who has sustained a brain injury and those who had not.

In the group that suffered from mild cognitive impairment, the patients who had received brain injuries had an 18 percent higher level of amyloid plaques than those who had not suffered a brain injury.

"Our results add merit to the idea that concussion and Alzheimer's disease brain pathology may be related," Mielke said. "However, the fact that we did not find a relationship in those without memory and thinking problems suggests that any association between head trauma and amyloid is complex."

Symptoms of Alzheimer's include problems with memory, disorientation, misinterpretation of spatial relationships, trouble making decisions, personality changes, and trouble performing everyday familiar tasks. It can also cause psychological symptoms such as depression.