Simple and choice reaction time in patients with human immunodeficiency virus infection.

The performance of 56 homosexual men infected with human immunodeficiency virus (HIV) was compared to that of 23 HIV antibody-seronegative controls on simple (SRT) and choice (CRT) reaction time tasks. Patients were classified into 3 groups according to Centers for Disease Control clinical criteria. There were 18 patients who had acquired immunodeficiency syndrome (AIDS), 18 who had AIDS-related complex (ARC), and 20 who were HIV antibody-seropositive but otherwise asymptomatic (HIV-Ab+). The SRT task consisted of 5 trials, each containing 10 target stimuli. The CRT task consisted of 10 trials, each containing 5 target stimuli randomly interspersed with 5 nontarget stimuli. The mean response latency of each of the patient groups on the SRT task was not significantly different from that of controls. However, the performance of patients with AIDS or ARC on the CRT task was significantly lower than that of controls, whereas that of HIV-Ab+ patients was not. Analysis of the quality of RT task performance also indicated that the impairment of processing efficiency at higher levels of task difficulty reflected a disruption of processing prior to the response selection stage.