Event-related potentials as indices of subclinical neurological differences in HIV patients during rapid decision making.

The authors examined decision making in HIV patients under slow and rapid information deliveries. Thirteen asymptomatic, HIV-infected (HIV+) subjects with known seroconversion dates and 13 healthy control subjects were instructed to detect the "oddball" target tones among nontarget tones during single-channel (slow) and dual-channel (rapid) deliveries. Event-related potentials (ERPs) from midline scalp sites, reaction time, and "hits" were recorded. Behaviorally, the two groups performed similarly, and during single-channel delivery they produced similar ERPs indexing target detection. However, during dual-channel delivery the HIV+ group showed atypical morphology in the region of the P300 cognitive decision-making component compared with the control group. Auditory ERPs elicited by rapid, dichotic stimulus presentations appeared sensitive to subclinical effects of HIV-related neuropathology in individuals who had been HIV-positive for 3 months to 8 years.