DECISION-MAKING SPEED IN HIV-1 INFECTION - A PRELIMINARY-REPORT

Objectives: To test the efficacy of reaction time measures derived from cognitive psychology as measures of subclinical cognitive slowing in individuals with HIV-1 infection. Design: Cognitive slowing is the primary deficit in AIDS dementia. One measure of cognitive slowing is decision-making speed, the discrepancy between simple and choice reaction times, which represents an index of central information processing time. Methods: Nineteen HIV-seropositive and 13 control subjects performed a detection and decision task in a reaction time procedure. All subjects were administered measures of simple and choice reaction time, a control measure of rate of verbral encoding, and measures of psychological distress. Results: Compared with controls, both symptomatic and asymptomatic HIV-seropositive subjects had significantly longer decision times, but performed the control task of rate of encoding normally. Simple reaction times correlated significantly with depression scores, but choice reaction times were unrelated to psychological distress. Conclusions: The results support mental slowing as the initial cognitive disturbance of HIV-1 infection and emphasize potential use of reaction times as markers of central nervous system involvement in HIV-1 infection.