In a new study, researchers examined a link between memory performance with hippocampal volume and history of concussion, which led some former NFL players to impaired memory problems in later life.

During the study, published in JAMA Neurology, researchers examined 28 retired athletes. Out of them, about eight athletes were diagnosed with mild cognitive impairment (MCI). The researchers also observed 21 cognitively healthy control group participants who didn’t have any history of concussion. In addition, six control participants, who were with MCI but no concussion history, were also a part of the study.

According to the study, for former athletes with concussion history without MCI, even they had normal verbal memory scores, they were found lower than people who did not have concussion history. The study also suggested that the scores were poor for people who suffering from MCI and concussion. As per the study, the scores were worse than the aforementioned group and the health controls.

Former players without a concussion demonstrated same hippocampal volumes compared with control participants. The study stated that former athletes who had at least one concussion with loss of consciousness had smaller hippocampal volumes compared with control subjects. The former athletes’, who were with MCI and concussion, left hippocampal volume was smaller than control participants with MCI.

The study stated that it has found a link between history of concussion with loss of consciousness and later-in-life decreases in hippocampal volume and memory performance in former athletes. “A history of G3 concussion in athletes with MCI was associated with greater hippocampal volume loss compared with control participants with MCI. Prospective longitudinal studies after a G3 concussion would add further insight to the mechanism of MCI development,” the study stated.