Differentially disrupted functional connectivity of the subregions of the inferior parietal lobule in Alzheimer’s disease
Recent research on Alzheimer’s disease (AD) has shown that the altered structure and function of the inferior parietal lobule (IPL) provides a promising indicator of AD. However, little is known about the functional connectivity of the IPL subregions in AD subjects. In this study, we collected resting-state functional magnetic resonance imaging data from 32 AD patients and 38 healthy controls. We defined seven subregions of the IPL according to probabilistic cytoarchitectonic atlases and mapped the whole-brain resting-state functional connectivity for each subregion. Using hierarchical clustering analysis, we identified three distinct functional connectivity patterns of the IPL subregions: the anterior IPL connected with the sensorimotor network (SMN) and salience network (SN); the central IPL had connectivity with the executive-control network (ECN); and the posterior IPL exhibited connections with the default-mode network (DMN). Compared with the controls, the AD patients demonstrated distinct disruptive patterns of the IPL subregional connectivity with these different networks (SMN, SN, ECN and DMN), which suggests the impairment of the functional integration in the IPL. Notably, we also observed that the IPL subregions showed increased connectivity with the posterior part of the DMN in AD patients, which potentially indicates a compensatory mechanism. Finally, these abnormal IPL functional connectivity changes were closely associated with cognitive performance. Collectively, we show that the subregions of the IPL present distinct functional connectivity patterns with various functional networks that are differentially impaired in AD patients. Our results also suggest that functional disconnection and compensation in the IPL may coexist in AD.
KeywordsSupramarginal gyrus Angular gyrus Network fMRI Alzheimer disease
This work was supported by the Natural Science Foundation of China (grant nos. 81030028, 81000606 and 81370037), the Beijing Natural Science Foundation (grant no. Z111107067311036 and Z101107052210002) and the National Science Fund for Distinguished Young Scholars (grant no. 81225012).
Conflict of interest
The authors declare no competing financial interests.
- Buckner RL, Sepulcre J, Talukdar T, Krienen FM, Liu H, Hedden T, Andrews-Hanna JR, Sperling RA, Johnson KA (2009) Cortical hubs revealed by intrinsic functional connectivity: mapping, assessment of stability, and relation to Alzheimer’s disease. J Neurosci 29(6):1860–1873CrossRefPubMedCentralPubMedGoogle Scholar
- Desikan RS, Cabral HJ, Fischl B, Guttmann CR, Blacker D, Hyman BT, Albert MS, Killiany RJ (2009) Temporoparietal MR imaging measures of atrophy in subjects with mild cognitive impairment that predict subsequent diagnosis of Alzheimer disease. Ajnr 30(3):532–538CrossRefPubMedCentralPubMedGoogle Scholar
- Dosenbach NU, Fair DA, Miezin FM, Cohen AL, Wenger KK, Dosenbach RA, Fox MD, Snyder AZ, Vincent JL, Raichle ME, Schlaggar BL, Petersen SE (2007) Distinct brain networks for adaptive and stable task control in humans. Proc Natl Acad Sci USA 104(26):11073–11078CrossRefPubMedCentralPubMedGoogle Scholar
- Dubois B, Feldman HH, Jacova C, Dekosky ST, Barberger-Gateau P, Cummings J, Delacourte A, Galasko D, Gauthier S, Jicha G, Meguro K, O’Brien J, Pasquier F, Robert P, Rossor M, Salloway S, Stern Y, Visser PJ, Scheltens P (2007) Research criteria for the diagnosis of Alzheimer’s disease: revising the NINCDS-ADRDA criteria. Lancet Neurol 6(8):734–746CrossRefPubMedGoogle Scholar
- Dubois B, Feldman HH, Jacova C, Cummings JL, Dekosky ST, Barberger-Gateau P, Delacourte A, Frisoni G, Fox NC, Galasko D, Gauthier S, Hampel H, Jicha GA, Meguro K, O’Brien J, Pasquier F, Robert P, Rossor M, Salloway S, Sarazin M, de Souza LC, Stern Y, Visser PJ, Scheltens P (2010) Revising the definition of Alzheimer’s disease: a new lexicon. Lancet Neurol 9(11):1118–1127CrossRefPubMedGoogle Scholar
- Mars RB, Jbabdi S, Sallet J, O’Reilly JX, Croxson PL, Olivier E, Noonan MP, Bergmann C, Mitchell AS, Baxter MG, Behrens TE, Johansen-Berg H, Tomassini V, Miller KL, Rushworth MF (2011) Diffusion-weighted imaging tractography-based parcellation of the human parietal cortex and comparison with human and macaque resting-state functional connectivity. J Neurosci 31(11):4087–4100CrossRefPubMedCentralPubMedGoogle Scholar
- Nelson PT, Abner EL, Scheff SW, Schmitt FA, Kryscio RJ, Jicha GA, Smith CD, Patel E, Markesbery WR (2009) Alzheimer’s-type neuropathology in the precuneus is not increased relative to other areas of neocortex across a range of cognitive impairment. Neurosci Lett 450(3):336–339CrossRefPubMedCentralPubMedGoogle Scholar
- Yan C, Zang Y (2010) DPARSF: a MATLAB toolbox for “Pipeline” data analysis of resting-state fMRI. Front Syst Neurosci 4:13Google Scholar
- Zuo XN, Kelly C, Di Martino A, Mennes M, Margulies DS, Bangaru S, Grzadzinski R, Evans AC, Zang YF, Castellanos FX, Milham MP (2010) Growing together and growing apart: regional and sex differences in the lifespan developmental trajectories of functional homotopy. J Neurosci 30(45):15034–15043CrossRefPubMedCentralPubMedGoogle Scholar