title: Reaction time slowing in HIV-1-infected individuals: role of the preparatory interval.
abstract: Psychomotor speed and directed attention were evaluated in 83 human immunodeficiency virus-1-infected individuals (HIV+) and 50 HIV-1 seronegative (HIV-) control participants using simple and choice reaction time (RT) tasks. The simple RT task included 1- and 3-s, irregularly varied preparatory intervals (PI) between the warning and target lights. Relative to the HIV- group, simple and choice RT were significantly slowed in the HIV+ group. Further, again relative to the HIV- controls, the HIV+ group did not show expected faster RT with increased response preparation time in the simple RT task. This also occurred in some HIV+ subjects who did not have psychomotor slowing. These findings suggest that RT performance in HIV-1-infected individuals may reflect separate processes associated with psychomotor slowing and impaired ability to direct attention. Possible neural mechanisms associated with control of these processes are discussed.
authors.affiliation: Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, Maryland, USA.
authors.forename: W A
authors.initials: WA
authors.lastname: Law
authors.forename: R L
authors.initials: RL
authors.lastname: Mapou
authors.forename: T L
authors.initials: TL
authors.lastname: Roller
authors.forename: A
authors.initials: A
authors.lastname: Martin
authors.forename: E D
authors.initials: ED
authors.lastname: Nannis
authors.forename: L R
authors.initials: LR
authors.lastname: Temoshok
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000175:diagnosis* / Q000523:psychology; D000328:Adult; D000339:Affect; D001288:Attention; D018023:HIV Seronegativity; D015497:HIV-1; D006801:Humans; D008297:Male; D011597:Psychomotor Performance; D011930:Reaction Time; D013997:Time Factors