Neurobiology of Disease (Aug 2016)
Prefrontal cortical volume loss is associated with stress-related deficits in verbal learning and memory in HIV-infected women
Abstract
Deficits in verbal learning and memory are a prominent feature of neurocognitive function in HIV-infected women, and are associated with high levels of perceived stress. To understand the neurobiological factors contributing to this stress-related memory impairment, we examined the association between stress, verbal memory, and brain volumes in HIV-infected women. Participants included 38 HIV-infected women (Mean age = 43.9 years) from the Chicago Consortium of the Women's Interagency HIV Study (WIHS). Participants underwent structural magnetic resonance imaging (MRI) and completed standardized measures of verbal learning and memory and stress (Perceived Stress Scale-10; PSS-10). Brain volumes were evaluated in a priori regions of interest, including the medial temporal lobe (MTL) and prefrontal cortex (PFC). Compared to HIV-infected women with lower stress (PSS-10 scores in lower two tertiles), HIV-infected women with higher stress (scores in the top tertile), performed worse on measures of verbal learning and memory and showed smaller volumes bilaterally in the parahippocampal gyrus, superior frontal gyrus, middle frontal gyrus, and inferior frontal gyrus (p's < 0.05). Reduced volumes in the inferior frontal gyrus, middle frontal gyrus, and superior frontal gyrus (all right hemisphere) were negatively associated with verbal learning and memory performance. Prefrontal cortical atrophy is associated with stress-related deficits in verbal learning and memory in HIV-infected women. The time course of these volume losses in relation to memory deficits has yet to be elucidated, but the magnitude of the volumetric differences between women with higher versus lower stress suggests a prolonged vulnerability due to chronic stress and/or early life trauma.