[1] Johns Hopkins Univ, Sch Med, Dept Neurol, Baltimore, MD 21205 USA
[2] Johns Hopkins Bloomberg Sch Publ Hlth, Johns Hopkins Biostat Ctr, Baltimore, MD USA
[3] Johns Hopkins Univ, Sch Med, Dept Med, Baltimore, MD 21205 USA
[4] Johns Hopkins Bloomberg Sch Publ Hlth, Dept Epidemiol, Baltimore, MD USA
[5] Johns Hopkins Bloomberg Sch Publ Hlth, Welch Ctr Prevent Epidemiol & Clin Res, Baltimore, MD USA
[6] Georgetown Univ, Med Ctr, Cognit Neuropsychol Lab, Ctr Aphasia Res & Rehabil, Washington, DC 20007 USA
[7] Johns Hopkins Univ, Sch Med, Dept Phys Med & Rehabil, Baltimore, MD USA
[8] Johns Hopkins Univ, Dept Cognit Sci, Baltimore, MD 21218 USA
[9] Johns Hopkins Univ, Sch Med, Dept Otolaryngol Head & Neck Surg, 601 N Caroline St,6th Floor, Baltimore, MD 21287 USA