Parietal intrahemispheric source connectivity of resting-state electroencephalographic alpha rhythms is abnormal in Naïve HIV patients.

Previous evidence showed abnormal parietal sources of resting-state electroencephalographic (EEG) delta (< 4 Hz) and alpha (8-12 Hz) rhythms in treatment-Naïve HIV (Naïve HIV) subjects, as cortical neural synchronization markers in quiet wakefulness. Here, we tested the hypothesis that these local abnormalities may be related to functional cortical dysconnectivity as an oscillatory brain network disorder. The present EEG database regarded 128 Naïve HIV and 60 Healthy subjects. The eLORETA freeware estimated lagged linear EEG source connectivity (LLC). The area under receiver operating characteristic (AUROC) curve indexed the accuracy in the classification between Healthy and HIV individuals. Parietal intrahemispheric LLC solutions in alpha sources were abnormally lower in the Naïve HIV than in the control group. Furthermore, those abnormalities were greater in the Naïve HIV subgroup with executive and visuospatial deficits than the Naïve HIV subgroup with normal cognition. AUROC curves of those LLC solutions exhibited moderate/good accuracies (0.75-0.88) in the discrimination between the Naïve HIV individuals with executive and visuospatial deficits vs. Naïve HIV individuals with normal cognition and control individuals. In quiet wakefulness, Naïve HIV subjects showed clinically relevant abnormalities in parietal alpha source connectivity. HIV may alter a parietal "hub" oscillating at the alpha frequency in quiet wakefulness as a brain network disorder.

Cortical sources of resting state electroencephalographic rhythms probe brain function in naïve HIV individuals.

OBJECTIVE: Here we evaluated the hypothesis that resting state electroencephalographic (EEG) cortical sources correlated with cognitive functions and discriminated asymptomatic treatment-naïve HIV subjects (no AIDS). METHODS: EEG, clinical, and neuropsychological data were collected in 103 treatment-naïve HIV subjects (88 males; mean age 39.8 years ±â€¯1.1 standard error of the mean, SE). An age-matched group of 70 cognitively normal and HIV-negative (Healthy; 56 males; 39.0 years ±â€¯2.0 SE) subjects, selected from a local university archive, was used for control purposes. LORETA freeware was used for EEG source estimation in fronto-central, temporal, and parieto-occipital regions of interest. RESULTS: Widespread sources of delta (<4 Hz) and alpha (8-12 Hz) rhythms were abnormal in the treatment-naïve HIV group. Fronto-central delta source activity showed a slight but significant (p < 0.05, corrected) negative correlation with verbal and semantic test scores. So did parieto-occipital delta/alpha source ratio with memory and composite cognitive scores. These sources allowed a moderate classification accuracy between HIV and control individuals (area under the ROC curves of 70-75%). CONCLUSIONS: Regional EEG abnormalities in quiet wakefulness characterized treatment-naïve HIV subjects at the individual level. SIGNIFICANCE: This EEG approach may contribute to the management of treatment-naïve HIV subjects at risk of cognitive deficits.