Accepted for Publication: February 12, 2015.
Published Online: May 18, 2015. doi:10.1001/jamaneurol.2015.0206.
Study concept and design: Strain, Womack, Conover, Hart, Kraut, Cullum.
Acquisition, analysis, or interpretation of data: Strain, Womack, Didehbani, Spence, Hart, Kraut, Cullum.
Drafting of the manuscript: Strain, Hart, Kraut, Cullum.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Strain, Spence, Hart.
Obtained funding: Hart.
Administrative, technical, or material support: Didehbani, Conover, Hart,
Study supervision: Womack, Spence, Hart, Kraut, Cullum.
Conflict of Interest Disclosures: None reported.
Funding/Support: This project was supported by the BrainHealth Institute for Athletes at the Center for BrainHealth, a research center at The University of Texas at Dallas, and grant P30Ag12300-19 from the National Institute on Aging.
Role of the Funder/Sponsor: The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
Additional Contributions: We thank the retired National Football League athletes who participated in the study and David Kennedy, PhD, the Center for Morphometric Analysis, for training data for the Functional Magnetic Resonance Imaging of the Brain integrated registration and segmentation tool. None of the individuals received financial compensation for their contributions.