Declined neural efficiency in cognitively stable human immunodeficiency virus patients

Area of Science:

• Neuroscience
• Neuroimaging
• Infectious Diseases

Background:

• Human immunodeficiency virus (HIV) infection can affect brain function.
• Assessing long-term neurological changes in HIV patients on treatment is crucial.
• Neurocognitively normal HIV-infected individuals require continued monitoring for brain changes.

Purpose of the Study:

• To compare brain activation changes over one year in HIV-infected and HIV-seronegative individuals.
• To investigate if stable neurocognition in HIV patients correlates with brain activity patterns.
• To determine the impact of HIV on the neural attention network over time.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used to measure brain activity.
• Participants (HIV-infected and HIV-seronegative controls) performed visual attention tasks with varying difficulty.
• Neuropsychological function and fMRI were assessed at baseline and after one year.

Main Results:

• HIV patients showed increased fMRI signal in prefrontal and parietal regions for difficult tasks.
• HIV-seronegative controls showed decreased brain activation in these regions over time.
• Significant interactions between HIV status and time were observed in frontal, parietal, and temporal regions.

Conclusions:

• HIV patients may compensate for potential neural decline by increasing attention network engagement.
• HIV-seronegative participants demonstrated increased neural efficiency or practice effects.
• Findings suggest potential ongoing brain injury in HIV patients, impacting neural efficiency despite clinical stability.