Wa. Law et al., REACTION-TIME SLOWING IN HIV-1-INFECTED INDIVIDUALS - ROLE OF THE PREPARATORY INTERVAL, Neuropsychology, development, and cognition. Section A, Journal of clinical and experimental neuropsychology, 17(1), 1995, pp. 122-133
Psychomotor speed and directed attention were evaluated in 83 human im
munodeficiency virus-1-infected individuals (HIV+) and 50 HIV-1 serone
gative (HIV-) control participants using simple and choice reaction ti
me (RT) tasks. The simple RT task included 1- and 3-s, irregularly var
ied preparatory intervals (PI) between the warning and target lights.
Relative to the HIV- group, simple and choice RT were significantly sl
owed 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 HI
V+ subjects who did not have psychomotor slowing. These findings sugge
st that RT performance in HIV-1-infected individuals may reflect separ
ate processes associated with psychomotor slowing and impaired ability
to direct attention. Possible neural mechanisms associated with contr
ol of these processes are discussed.