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چکیده
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Introduction: The effects of HIV virus on the brain can be seen, even after antiretroviral treatment. These have been shown using brain imaging methods such as resting-state fMRI (rs-fMRI) and Volumetric Brain Morphometry (VBM). Our aim in this study was to replicate previous findings, and provide evidence for a lateralized reduction in functional connectivity and volumetric measures in this population. Method: We acquired structural and functional images (5 minute resting state) from 25 individuals, 12 HIV-infected patients and 13 non-clinical ones, using an Avanto Siemens 1.5t MR scanner. All images were preprocessed (i.e., spatial normalization with modulation, segmentation, and smoothing, with DARTEL) using SPM12 and relevant toolboxes under Matlab software. The structural MRI images (axial, T1-weighted) were analyzed using VBM and LI toolbox (for anatomical lateralization). The BOLD images were analyzed for functional connectivities and lateralization using CONN toolbox. The pre-processed functional data were de-noised and checked for quality assurance. Results: A second-level analysis was done using VBM analysis (t-test) on gray matter (p < 0.001, corrected) and white matter (0.001, uncorrected), revealing a decreased volume in HIV-infected patients compared to Control, with a stronger left-lateralized, especially in white matter. The ROI-to- ROI and seed-to-voxel maps (ALFF and fALFF, < 0.1 Hz frequency band) were compared between HIV-infected patients and the control group (applying p < 0.001, corrected). The results revealed decreases in functional connectivity especially from seed in right-lateralized frontoparietal connections in patients compared to control group. Also, lower connectivity was found in the patient group, mainly in default mode network. Conclusion: The results of HIV-infected patients showed a decrease in brain volume which was mainly left-lateralized, and involved white matter. On the other hand, the functional connectivity results also r
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