HIV-associated neurocognitive disorders remain prevalent despite effective anti-retroviral treatments, and numerous studies indicate that these cognitive impairments impact everyday functioning. Since HIV-infected individuals can now anticipate a normal lifespan, the question arises as to whether real-world functioning in individuals with HIV-related cognitive deficits can be improved via behavioral interventions, with the goal of minimizing disability and enhancing quality of life. Reduced processing speed (PS) is a hallmark change associated with HIV-associated neurocognitive disorders (HAND). We have shown that such deficits are associated with poor driving performance as assessed on driving simulators and during on-road drives, and that impairments in the Useful Field of View (UFOV) predict on-road crashes beyond the information provided by standard neuropsychological (NP) testing. Individuals with PS deficits also have greater difficulty in multi tasking various activities associated with everyday functioning.
The specific aims for this revised project are: 1) to develop a protocol for, and determine the feasibility of, implementing a computer-based visual PS training program for individuals with HAND and PS deficits, 2) to determine whether visual PS training improves performance on related cognitive measures (including UFOV), driving simulations, and multi-tasking, and 3) to examine the possible mechanisms of such improvements via eye tracking technology. Fifty HIV+ drivers with HAND and established PS deficits will be randomized to either a) computerized visual PS training or b) a control condition. Both groups will complete the training or control task twice weekly for 8 weeks. Participants will then be evaluated on cognitive measures assessing PS and other cognitive abilities, driving simulations previously shown to be predictive of on-road performance, and a multi-tasking test of everyday functioning. Assessments will take place at baseline, following the intervention/control phase, and then 6 months following treatment termination to determine whether any improvements in performance persist. To better understand the mechanisms behind any improvement, we will utilize an eye-tracking system to assess visual scanning patterns while participants are engaged in an in-vehicle information system simulation (pre- and post-intervention). These will then be analyzed in relation to absolute performance and treatment effects. The results of this project will provide preliminary evidence regarding the feasibility and possible efficacy and mechanisms of improving PS-related deficits at a time when HIV-associated cognitive disorders appear unresolvable via pharmaceutical treatments alone, and lay the foundation for future studies to examine these issues in a more definitive manner.
HIV-related problems with thinking and memory continue despite effective medical treatments for disease- related complications, and these problems affect a person's ability to carryout daily activities. This project examines whether training to improve how quickly a person can think also improves his/her performance on real-world tasks, such as driving an automobile or doing more than one task at a time.