The effect of HIV infection on frontostriatal inhibitory control in the era of combined antiretroviral therapy

Keywords
No Thumbnail Available
Issue Date
2016-07-01
Language
en
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Studies on brain activity and connectivity in Human Immunodeficiency Virus (HIV) suggest that frontostriatal dysfunction plays a role in HIV-associated cognitive deficits. However, almost no research has been done to investigate frontostriatal functioning in a HIV population that is virally suppressed with combined antiretroviral therapy (cART). In this study, 27 HIV-positive participants, stable on cART and with an undetectable viral load, performed a stop signal anticipation task (SSAT) while being scanned with functional MRI (fMRI). This task activates the striatum during reactive inhibition (i.e. outright stopping of a response) and engages the frontostriatal network during proactive inhibition (i.e. anticipation of stopping). Results showed normal striatal activity in HIV+ participants during both reactive and proactive inhibition. During proactive inhibition, HIV+ participants showed less reaction time slowing during anticipation of a stop signal. This was paralleled in the brain by decreased dynamic activation in the right inferior frontal gyrus (IFG) with increased stop-signal probability, as well as decreased functional connectivity between the right striatum and the right IFG. These results suggest normal striatal functioning in a virally suppressed HIV population, but dysfunctional frontal activity and decreased frontostriatal connectivity. These findings serve as a stepping stone to research that distinguishes between the effects of HIV-infection and cART on frontostriatal functioning.
Description
Citation
Faculty
Faculteit der Sociale Wetenschappen