HIV-related decreased brain activity during a semantic memory task is reflected in spontaneous brain functional connectivity

Abstract

BackgroundThe primary goal was to examine HIV-related changes in brain activation during a semantic memory task. The secondary goal was to assess whether the functional connectivity of the brain regions showing altered activity during the semantic memory task is related to HIV serostatus.Participants and procedureThe total group of 17 male subjects, aged on average 44 years, included 8 HIV+/cART+ and 9 demographically matched healthy comparators. Participants completed Famous Names Recognition task-functional magnetic resonance imaging (fMRI) and resting state fMRI.ResultsWe found an effect of HIV status on brain activation during the semantic memory task, despite comparable accuracy and reaction time across groups. Compared to healthy individuals, in HIV+ participants recognition of famous names elicited less activity in the fronto-striatal network, particularly in the left caudate nucleus (p = .049), left inferior frontal gyrus (p = .047), left thalamus (p = .031) and right thalamus (p = .047), as well as in the left middle occipital gyrus (p = .028). Although an effect of HIV status on functional connectivity of the brain regions showing altered activity during semantic memory task was not observed, resting-state activation of those regions was significantly correlated with performance on cognitive domains of attention, executive functioning, psychomotor speed and semantic skills.ConclusionsOur findings suggest the presence of functional brain network reorganization in HIV+/cART+ patients, particu-larly in subcortical regions of the fronto-striatal network, in the absence of neurocognitive decline.