[1] Georgetown Univ, Med Ctr, Dept Neurosci, Washington, DC 20057 USA
[2] Univ Maryland, Dept Microbiol & Immunol, Inst Human Virol, Baltimore, MD 21201 USA
[3] NINDS, Lab Mol Med & Neurosci, NIH, Bethesda, MD 20892 USA
[4] Univ Illinois, Dept Psychiat, Chicago, IL 60612 USA
[5] Univ Illinois, Dept Psychol, Chicago, IL 60680 USA
[6] Georgetown Univ, Med Ctr, Dept Neurol, Washington, DC 20057 USA
[7] Georgetown Univ, Med Ctr, Dept Med, Washington, DC 20057 USA