Overview

• Two complementary papers published in Neurology and JAMA Network Open report cross-sectional associations between higher annual heading exposure and subtle microstructural disruption near the brain’s cortical surface.
• The studies analyzed 352 adult amateur soccer players and 77 non-collision athletes, with exposure groups ranging from about 105 to more than 3,000 headers per year.
• Abnormalities localized to juxtacortical white matter in temporal, orbitofrontal and parietal regions, with the JAMA analysis showing a fuzzier gray–white transition in the orbitofrontal cortex among players exceeding roughly 1,000 headers annually.
• Players with greater disruption in these regions performed worse on verbal learning and memory tests, and mediation analysis indicated that the microstructural changes partially explained the relationship between heading frequency and cognition.
• Authors stress the findings show association rather than causation, noting self-reported exposure and single-timepoint scans as limitations and calling for longitudinal, mechanistic studies and potential imaging-based monitoring approaches.