Age-related Increase in brain reserve in HIV subject during attention tasks
Yakupov R, Girton L, Nash T, Nakama H, Ernst T, Chang L
University of Hawaii, John A. Burns School of Medicine
Aging and HIV-infection both may lead to decreased ability to attend. Functional MRI was performed in 39 HIV-subjects [17 with cognitive deficits (HIV-CD) and 22 neuroasymptomatic (HIV-NA)] and 19 seronegative controls (SN) during visual attention tasks to evaluate possible interactive effects of aging and HIV. Age-dependent increases in activation were greater in the parietal regions of HIV-NA, but in the prefrontal regions of HIV-CD. These findings suggest, with aging, HIV may cause even less efficient usage of the normal network, but greater usage of the reserve regions. Cognitive deficits ensued in HIV-CD when the reserve capacity was exhausted on more difficult tasks.