[1] Univ Calif Irvine, Sch Med, Dept Neurol, Irvine, CA USA
[2] Natl Inst Neurol & Neurosurg, Expt Psychol Lab, Mexico City, DF, Mexico
[3] Univ Calif Los Angeles, Sch Med, Dept Neurol, Los Angeles, CA 90024 USA
[4] Univ Calif Los Angeles, Sch Med, Dept Psychiat & Behav Sci, Los Angeles, CA 90024 USA