Characterization of cortical volume and whole-brain functional connectivity in Parkinson's disease patients: a MRI study combined with physiological aging brain changes

Abstract

This study employed multiple MRI features to comprehensively evaluate the abnormalities in morphology, and functionality associated with Parkinson's disease (PD) and distinguish them from normal physiological changes. For investigation purposes, three groups: 32 patients with PD, 42 age-matched healthy controls (HCg1), and 33 young and middle-aged controls (HCg2) were designed. The aim of the current study was to differentiate pathological cortical changes in PD from age-related physiological cortical volume changes. Integrating these findings with functional MRI changes to characterize the effects of PD on whole-brain networks. Cortical volumes in the bilateral temporal lobe, frontal lobe, and cerebellum were significantly reduced in HCg1 compared to HCg2. Although no significant differences in cortical volume were observed between PD patients and HCg1, the PD group exhibited pronounced abnormalities with significantly lower mean connectivity values compared to HCg1. Conversely, physiological functional changes in HCg1 showed markedly higher mean connectivity values than in HCg2. By integrating morphological and functional assessments, as well as network characterization of physiological aging, this study further delineates the distinct characteristics of pathological changes in PD.

Keywords: Parkinson’s disease; cortex; fMRI; functional connectivity; morphology.

Figure 1

(A) Illustrates a significant reduction in cortical volume in HCg1 compared to HCg2 (blue area). The areas of difference include the bilateral cerebellum, frontal lobe, temporal lobe, and insula (p < 0.05, FDR correction p < 0.01). As shown in (B), there was no significant change in the cortical volume of the PD group compared to the HCg1 group.

Figure 2

(A–C) Are the functional connectivity results for the comparison of PD with HCg1; (B) is the functional connectivity matrix plot; (C) is the histogram of the average functional connectivity values for both groups; (D–F) are the functional connectivity results for the comparison of HCg1 with HCg2; (E) is the functional connectivity matrix plot; F is a histogram of the mean connectivity values between HCg1 and HCg2. L/l, Left; R/r, Right; IPS=Intraparietal sulci; SPL, Superior Parietal Lobule; PO=Parietal Operculum Cortex; PT, Planum Temporale; CO=Central Opercular Cortex; IC, insular Cortex; aSMG, Supramarginal Gyrus, anterior division; IFG oper, Inferior Frontal Gyrus, pars percularis; IFG tri, Inferior Frontal Gyrus, pars triangularis; FOrb, Frontal Orbital Cortex; pSTG, Superior Temporal Gyrus, posterior division; pITG, Inferior Temporal Gyrus, posterior division; aITG, Inferior Temporal Gyrus, anterior division; Cereb1, Cerebelum Crus1; pMTG, Middle Temporal Gyrus, posterior division; MidFG, Middle Frontal Gyrus; SFG, Superior Frontal Gyrus; FP, Frontal Pole; sLOC, Lateral Occipital Cortex, superior division; LP=; PC, Cingulate Gyrus, posterior division; PCC, Posterior Cingulate Cortex; AG, Angular Gyrus; SMA, Supplementary Motor Area; PreCG, Precentral Gyrus; PosCG, Postcentral Gyrus; SPL, Superior Parietal Lobule; Ver6, Vermis 6; SCC, Supracalcarine Cortex.