[en] [en] BACKGROUND: Alterations of intrinsic networks from resting state fMRI (rs-fMRI) have been suggested as functional biomarkers of Alzheimer's disease (AD).
OBJECTIVE: To determine the diagnostic accuracy of multicenter rs-fMRI for prodromal and preclinical stages of AD.
METHODS: We determined rs-fMRI functional connectivity based on Pearson's correlation coefficients and amplitude of low-frequency fluctuation in people with subjective cognitive decline, people with mild cognitive impairment, and people with AD dementia compared with healthy controls. We used data of 247 participants of the prospective DELCODE study, a longitudinal multicenter observational study, imposing a unified fMRI acquisition protocol across sites. We determined cross-validated discrimination accuracy based on penalized logistic regression to account for multicollinearity of predictors.
RESULTS: Resting state functional connectivity reached significant cross-validated group discrimination only for the comparison of AD dementia cases with healthy controls, but not for the other diagnostic groups. AD dementia cases showed alterations in a large range of intrinsic resting state networks, including the default mode and salience networks, but also executive and language networks. When groups were stratified according to their CSF amyloid status that was available in a subset of cases, diagnostic accuracy was increased for amyloid positive mild cognitive impairment cases compared with amyloid negative controls, but still inferior to the accuracy of hippocampus volume.
CONCLUSION: Even when following a strictly harmonized data acquisition protocol and rigorous scan quality control, widely used connectivity measures of multicenter rs-fMRI do not reach levels of diagnostic accuracy sufficient for a useful biomarker in prodromal stages of AD.
Disciplines :
Neurology
Author, co-author :
Teipel, Stefan J; Department of Psychosomatic Medicine, University of Rostock, Rostock, Germany ; German Center for Neurodegenerative Diseases (DZNE), Rostock, Germany
Metzger, Coraline D; Institute of Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University, Magdeburg, Germany ; Department of Psychiatry and Psychotherapy, Otto-von-Guericke University, Magdeburg, Germany ; German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
Brosseron, Frederic; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany ; Department for Neurodegenerative Diseases and Geriatric Psychiatry, University Hospital Bonn, Bonn, Germany
Buerger, Katharina; German Center for Neurodegenerative Diseases (DZNE), Munich, Germany ; Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
Brueggen, Katharina; German Center for Neurodegenerative Diseases (DZNE), Rostock, Germany
Catak, Cihan; Institute for Stroke and Dementia Research (ISD), University Hospital, LMU Munich, Munich, Germany
Diesing, Dominik; Department of Psychiatry and Psychotherapy, Campus Benjamin Franklin, Charité - Universitätsmedizin Berlin, Berlin, Germany
Dobisch, Laura; German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
Fliebach, Klaus; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany ; Department for Neurodegenerative Diseases and Geriatric Psychiatry, University Hospital Bonn, Bonn, Germany
Franke, Christiana; Department of Psychiatry and Psychotherapy, Campus Charité Mitte, Charité - Universitätsmedizin Berlin, Berlin, Germany ; German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
HENEKA, Michael ; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany ; Department for Neurodegenerative Diseases and Geriatric Psychiatry, University Hospital Bonn, Bonn, Germany
Kilimann, Ingo; Department of Psychosomatic Medicine, University of Rostock, Rostock, Germany ; German Center for Neurodegenerative Diseases (DZNE), Rostock, Germany
Kofler, Barbara; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany ; Department of Psychiatry and Psychotherapy, University of Bonn, Bonn, Germany
Menne, Felix; Department of Psychiatry and Psychotherapy, Campus Benjamin Franklin, Charité - Universitätsmedizin Berlin, Berlin, Germany ; German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
Peters, Oliver; Department of Psychiatry and Psychotherapy, Campus Benjamin Franklin, Charité - Universitätsmedizin Berlin, Berlin, Germany ; German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
Polcher, Alexandra; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
Priller, Josef; Department of Psychiatry and Psychotherapy, Campus Charité Mitte, Charité - Universitätsmedizin Berlin, Berlin, Germany ; German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
Schneider, Anja; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany ; Department for Neurodegenerative Diseases and Geriatric Psychiatry, University Hospital Bonn, Bonn, Germany
Spottke, Annika; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany ; Department of Neurology, University of Bonn, Bonn, Germany
Spruth, Eike J; Department of Psychiatry and Psychotherapy, Campus Charité Mitte, Charité - Universitätsmedizin Berlin, Berlin, Germany ; German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
Thelen, Manuela; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany ; Department of Psychiatry, University of Cologne, Cologne, Germany
Thyrian, René J; German Center for Neurodegenerative Diseases (DZNE), Greifswald, Germany
Wagner, Michael; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany ; Department for Neurodegenerative Diseases and Geriatric Psychiatry, University Hospital Bonn, Bonn, Germany
Düzel, Emrah; Institute of Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University, Magdeburg, Germany ; German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
Jessen, Frank; German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany ; Department of Psychiatry, University of Cologne, Cologne, Germany
Dyrba, Martin; German Center for Neurodegenerative Diseases (DZNE), Rostock, Germany
Albert MS, DeKosky ST, Dickson D, Dubois B, Feldman HH, Fox NC, Gamst A, Holtzman DM, Jagust WJ, Petersen RC, Snyder PJ, Carrillo MC, Thies B, PhelpsCH(2011) The diagnosis of mild cognitive impairment due to Alzheimer's disease: Recommendations from the National Institute on Aging-Alzheimer's Association workgroups on diagnostic guidelines for Alzheimer's disease. Alzheimers Dement 7, 270-279.
McKhann GM, Knopman DS, Chertkow H, Hyman BT, Jack Jr CR, Kawas CH, Klunk WE, Koroshetz WJ, Manly JJ, Mayeux R, Mohs RC, Morris JC, Rossor MN, Scheltens P, Carrillo MC, Thies B, Weintraub S, Phelps CH (2011) The diagnosis of dementia due to Alzheimer's disease: Recommendations from the National Institute on Aging-Alzheimer's Association workgroups on diagnostic guidelines for Alzheimer's disease. Alzheimers Dement 7, 263-269.
Dubois B, Feldman HH, Jacova C, Hampel H, Molinuevo JL, Blennow K, DeKosky ST, Gauthier S, Selkoe D, Bateman R, Cappa S, Crutch S, Engelborghs S, Frisoni GB, Fox NC, Galasko D, Habert MO, Jicha GA, Nordberg A, Pasquier F, Rabinovici G, Robert P, Rowe C, Salloway S, Sarazin M, Epelbaum S, de Souza LC, Vellas B, Visser PJ, Schneider L, Stern Y, Scheltens P, Cummings JL (2014) Advancing research diagnostic criteria for Alzheimer's disease: The IWG-2 criteria. Lancet Neurol 13, 614-629.
Petersen RC (2004) Mild cognitive impairment as a diagnostic entity. J Intern Med 256, 183-194.
Jessen F, Amariglio RE, van Boxtel M, Breteler M, Ceccaldi M, Chetelat G, Dubois B, Dufouil C, Ellis KA, van der Flier WM, Glodzik L, van Harten AC, de Leon MJ, McHugh P, MielkeMM, Molinuevo JL, Mosconi L, Osorio RS, Perrotin A, Petersen RC, Rabin LA, Rami L, Reisberg B, Rentz DM, Sachdev PS, de la Sayette V, Saykin AJ, Scheltens P, Shulman MB, Slavin MJ, Sperling RA, Stewart R, Uspenskaya O, Vellas B, Visser PJ, Wagner M, Subjective Cognitive Decline Initiative Working Group (2014) A conceptual framework for research on subjective cognitive decline in preclinical Alzheimer's disease. Alzheimers Dement 10, 844-852.
Liu K, Chen K, Yao L, Guo X (2017) Prediction of mild cognitive impairment conversion using a combination of independent component analysis and the Cox model. Front Hum Neurosci 11, 33.
Vannini P, Hanseeuw B, Munro CE, Amariglio RE, Marshall GA, Rentz DM, Pascual-Leone A, Johnson KA, Sperling RA (2017) Hippocampal hypometabolism in older adults with memory complaints and increased amyloid burden. Neurology 88, 1759-1767.
Teipel S, Grothe MJ, Alzheimer's Disease Neuroimaging Initiative (2016) Does posterior cingulate hypometabolism result from disconnection or local pathology across preclinical and clinical stages of Alzheimer's disease?. Eur J Nucl Med Mol Imaging 43, 526-536.
Mosconi L, Mistur R, Switalski R, Tsui WH, Glodzik L, Li Y, Pirraglia E, De Santi S, Reisberg B, Wisniewski T, de Leon MJ (2009) FDG-PET changes in brain glucose metabolism from normal cognition to pathologically verified Alzheimer's disease. Eur J Nucl Med Mol Imaging 36, 811-822.
Mosconi L (2005) Brain glucose metabolism in the early and specific diagnosis of Alzheimer's disease. FDG-PET studies in MCI and AD. Eur J Nucl Med Mol Imaging 32, 486-510.
Teipel S, Grothe MJ, Zhou J, Sepulcre J, Dyrba M, Sorg C, Babiloni C (2016) Measuring cortical connectivity in Alzheimer's disease as a brain neural network pathology: Toward clinical applications. J Int Neuropsychol Soc 22, 138-163.
Vemuri P, Jones DT, Jack Jr CR (2012) Resting state functional MRI in Alzheimer's disease. Alzheimers Res Ther 4, 2.
Freeman RD, Li B (2016) Neural-metabolic coupling in the central visual pathway. Philos Trans R Soc Lond B Biol Sci 371, 20150357.
Koch W, Teipel S, Mueller S, Benninghoff J, Wagner M, Bokde AL, Hampel H, Coates U, Reiser M, Meindl T (2012) Diagnostic power of default mode network resting state fMRI in the detection of Alzheimer's disease. Neurobiol Aging 33, 466-478.
Balthazar ML, de Campos BM, Franco AR, Damasceno BP, Cendes F (2014) Whole cortical and default mode network mean functional connectivity as potential biomarkers for mild Alzheimer's disease. Psychiatry Res 221, 37-42.
Dyrba M, Barkhof F, Fellgiebel A, Filippi M, Hausner L, Hauenstein K, KirsteT, Teipel SJ, EDSDstudy group (2015) Predicting prodromal Alzheimer's disease in subjects with mild cognitive impairment using machine learning classification of multimodal multicenter diffusion-tensor and magnetic resonance imaging data. J Neuroimaging 25, 738-747.
De Marco M, Beltrachini L, Biancardi A, Frangi AF, Venneri A (2017) Machine-learning support to individual diagnosis of mild cognitive impairment using multimodal MRI and cognitive assessments. Alzheimer Dis Assoc Disord 31, 278-286.
Magnotta VA, Friedman L, First B (2006) Measurement of signal-to-noise and contrast-to-noise in the fBIRN Multicenter Imaging Study. J Digit Imaging 19, 140-147.
Lin Q, Dai Z, Xia M, Han Z, Huang R, Gong G, Liu C, Bi Y, He Y (2015) A connectivity-based test-retest dataset of multi-modal magnetic resonance imaging in young healthy adults. Sci Data 2, 150056.
Jovicich J, Minati L, Marizzoni M, Marchitelli R, Sala-Llonch R, Bartres-Faz D, Arnold J, Benninghoff J, Fiedler U, Roccatagliata L, Picco A, Nobili F, Blin O, Bombois S, Lopes R, Bordet R, Sein J, Ranjeva JP, Didic M, Gros-Dagnac H, Payoux P, Zoccatelli G, Alessandrini F, Beltramello A, Bargallo N, Ferretti A, Caulo M, Aiello M, Cavaliere C, Soricelli A, Parnetti L, Tarducci R, Floridi P, Tsolaki M, Constantinidis M, Drevelegas A, Rossini PM, Marra C, Schonknecht P, Hensch T, Hoffmann KT, Kuijer JP, Visser PJ, Barkhof F, Frisoni GB, PharmaCog Consortium (2016) Longitudinal reproducibility of defaultmode network connectivity in healthy elderly participants: A multicentric resting-state fMRI study. Neuroimage 124, 442-454.
Suckling J, Barnes A, Job D, Brennan D, Lymer K, Dazzan P, Marques TR, MacKay C, McKie S, Williams SR, Williams SC, Deakin B, Lawrie S (2012) The Neuro/PsyGRID calibration experiment: Identifying sources of variance and bias in multicenter MRI studies. Hum Brain Mapp 33, 373-386.
Teipel SJ, Wohlert A, Metzger C, Grimmer T, Sorg C, Ewers M, Meisenzahl E, Kloppel S, Borchardt V, Grothe MJ, Walter M, DyrbaM(2017) Multicenter stability of resting state fMRI in the detection of Alzheimer's disease and amnestic MCI. Neuroimage Clin 14, 183-194.
Moodley KK, Chan D (2014) The hippocampus in neurodegenerative disease. Front Neurol Neurosci 34, 95-108.
Cox RW(1996) AFNI: Software for analysis and visualization of functional magnetic resonance neuroimages. Comput Biomed Res 29, 162-173.
Zou H, Hastie T (2005) Regularization and variable selection via the elastic net. J R Statist Soc B 67, 301-320.
de Vos F, Schouten TM, Hafkemeijer A, Dopper EG, van Swieten JC, de Rooij M, van der Grond J, Rombouts SA (2016) Combining multiple anatomical MRI measures improves Alzheimer's disease classification. Hum Brain Mapp 37, 1920-1929.
Teipel SJ, Grothe MJ, Metzger CD, Grimmer T, Sorg C, Ewers M, Franzmeier N, Meisenzahl E, Kloppel S, Borchardt V, Walter M, Dyrba M (2017) Robust detection of impaired resting state functional connectivity networks in Alzheimer's disease using elastic net regularized regression. Front Aging Neurosci 8, 318.
Teipel SJ, Kurth J, Krause B, Grothe MJ, Alzheimer's Disease Neuroimaging Initiative (2015) The relative importance of imaging markers for the prediction of Alzheimer's disease dementia in mild cognitive impairment - Beyond classical regression. Neuroimage Clin 8, 583-593.
Trzepacz PT, Yu P, Sun J, Schuh K, Case M, Witte MM, Hochstetler H, HakeA, Alzheimer's Disease Neuroimaging Initiative (2014) Comparison of neuroimaging modalities for the prediction of conversion from mild cognitive impairment to Alzheimer's dementia. Neurobiol Aging 35, 143-151.
Jessen F, Spottke A, Boecker H, Brosseron F, Buerger K, Catak C, Fliessbach K, Franke C, Fuentes M, Heneka MT, Janowitz D, Kilimann I, Laske C, Menne F, Nestor P, Peters O, Priller J, Pross V, Ramirez A, Schneider A, Speck O, Spruth EJ, Teipel S, Vukovich R, Westerteicher C, Wiltfang J, Wolfsgruber S, Wagner M, Düzel E (2018) Design and first baseline data of the DZNE multicenter observational study on predementia Alzheimer's disease (DELCODE). Alzheimers Res Ther 10, 15.
Morris JC, Heyman A, Mohs RC, Hughes JP, van Belle G, Fillenbaum G, Mellits ED, Clark C (1989) The Consortium to Establish a Registry for Alzheimer's Disease (CERAD). Part I. Clinical and neuropsychological assessment of Alzheimer's disease. Neurology 39, 1159-1165.
Folstein MF, Folstein SE, McHugh PR (1975) Mini-mentalstate: A practical method for grading the cognitive state of patients for the clinician. J Psychiatr Res 12, 189-198.
Morris JC (1993) The Clinical Dementia Rating (CDR): Current version and scoring rules. Neurology 43, 2412-2414.
Wechsler D (1987) Wechsler Memory Scale-Revised, The Psychological Corporation, New York.
Ashburner J (2007) A fast diffeomorphic image registration algorithm. Neuroimage 38, 95-113.
Kurth F, Gaser C, Luders E (2015) A 12-step user guide for analyzing voxel-wise gray matter asymmetries in statistical parametric mapping (SPM). Nat Protoc 10, 293-304.
Chao-Gan Y, Yu-Feng Z (2010) DPARSF: A MATLAB Toolbox for "pipeline" data analysis of resting-state fMRI. Front Syst Neurosci 4, 13.
Shirer WR, Jiang H, Price CM, Ng B, Greicius MD (2015) Optimization of rs-fMRI pre-processing for enhanced signal-noise separation, test-retest reliability, and group discrimination. Neuroimage 117, 67-79.
MurphyK, Birn RM, HandwerkerDA, Jones TB, Bandettini PA (2009) The impact of global signal regression on resting state correlations: Are anti-correlated networks introduced?. Neuroimage 44, 893-905.
Power JD, Mitra A, Laumann TO, Snyder AZ, Schlaggar BL, Petersen SE (2014) Methods to detect, characterize, and remove motion artifact in resting state fMRI. Neuroimage 84, 320-341.
Yan CG, Cheung B, Kelly C, Colcombe S, Craddock RC, Di Martino A, Li Q, Zuo XN, Castellanos FX, Milham MP (2013) A comprehensive assessment of regional variation in the impact of head micromovements on functional connectomics. Neuroimage 76, 183-201.
Shirer WR, Ryali S, Rykhlevskaia E, Menon V, Greicius MD (2012) Decoding subject-driven cognitive states with whole-brain connectivity patterns. Cereb Cortex 22, 158-165.
Craddock RC, James GA, Holtzheimer PE, Hu XP, Mayberg HS (2012) A whole brain fMRI atlas generated via spatially constrained spectral clustering. Human Brain Mapp 33, 1914-1928.
Schaefer A, Kong R, Gordon EM, Laumann TO, Zuo X-N, Holmes AJ, Eickhoff SB, Yeo BTT (2017) Localglobal parcellation of the human cerebral cortex from intrinsic functional connectivity MRI. Cereb Cortex. doi: 10.1093/cercor/bhx179
Fisher RA (1915) Frequency distribution of the values of the correlation coefficient in samples from an indefinitely large population. Biometrika 10, 507.
Frisoni GB, Jack Jr CR, Bocchetta M, Bauer C, Frederiksen KS, Liu Y, Preboske G, Swihart T, Blair M, Cavedo E, Grothe MJ, Lanfredi M, Martinez O, Nishikawa M, Portegies M, Stoub T, Ward C, Apostolova LG, Ganzola R, Wolf D, Barkhof F, Bartzokis G, DeCarli C, Csernansky JG, deToledo-Morrell L, Geerlings MI, Kaye J, Killiany RJ, Lehericy S, Matsuda H, O'Brien J, Silbert LC, Scheltens P, Soininen H, Teipel S, Waldemar G, Fellgiebel A, Barnes J, Firbank M, Gerritsen L, HennemanW, Malykhin N, Pruessner JC, Wang L, Watson C, Wolf H, deLeon M, Pantel J, Ferrari C, Bosco P, Pasqualetti P, Duchesne S, Duvernoy H, Boccardi M, EADC-ADNIWorking Group on The Harmonized Protocol for Manual Hippocampal Volumetry and for the Alzheimer's Disease Neuroimaging Initiative (2015) The EADC-ADNI Harmonized Protocol for manual hippocampal segmentation on magnetic resonance: Evidence of validity. Alzheimers Dement 11, 111-125.
Wolf D, Bocchetta M, Preboske GM, Boccardi M, Grothe MJ, Alzheimer's Disease Neuroimaging Initiative (2017) Reference standard space hippocampus labels according to the EADC-ADNI harmonized protocol: Utility in automated volumetry. Alzheimers Dement 13, 893-902.
Janelidze S, Zetterberg H, Mattsson N, Palmqvist S, Vanderstichele H, Lindberg O, van Westen D, Stomrud E, Minthon L, BlennowK, Swedish Bio Fsg, HanssonO(2016) CSF Abeta42/Abeta40 and Abeta42/Abeta38 ratios: Better diagnostic markers of Alzheimer disease. Ann Clin Transl Neurol 3, 154-165.
Friedman J, Hastie T, Tibshirani R (2010) Regularization paths for generalized linear models via coordinate descent. J Stat Softw 33, 1-22.
Chen X, Zhang H, Zhang L, Shen C, LeeSW, ShenD(2017) Extraction of dynamic functional connectivity from brain grey matter and white matter for MCI classification. Hum Brain Mapp 38, 5019-5034.
Brier MR, Thomas JB, Snyder AZ, Wang L, Fagan AM, Benzinger T, Morris JC, Ances BM (2014) Unrecognized preclinical Alzheimer disease confounds rs-fcMRI studies of normal aging. Neurology 83, 1613-1619.
Weiler M, de Campos BM, Teixeira CVL, Casseb RF, Carletti-Cassani A, Vicentini JE, Magalhaes TNC, Talib LL, ForlenzaOV, Balthazar MLF (2017) Intranetwork and internetwork connectivity in patients with Alzheimer disease and the association with cerebrospinal fluid biomarker levels. J Psychiatry Neurosci 42, 366-377.
Malpas CB, Saling MM, Velakoulis D, Desmond P, O'Brien TJ (2016) Differential functional connectivity correlates of cerebrospinal fluid biomarkers in dementia of the Alzheimer's type. Neurodegener Dis 16, 147-151.
Luo X, Qiu T, Jia Y, Huang P, Xu X, Yu X, Shen Z, Jiaerken Y, Guan X, Zhou J, Zhang M, Alzheimer's Disease Neuroimaging Initiative (2017) Intrinsic functional connectivity alterations in cognitively intact elderlyAPOEepsilon4 carriers measured by eigenvector centrality mapping are related to cognition and CSF biomarkers: A preliminary study. Brain Imaging Behav 11, 1290-1301.
Demirtas M, Falcon C, Tucholka A, Gispert JD, Molinuevo JL, Deco G (2017) A whole-brain computational modeling approach to explain the alterations in resting-state functional connectivity during progression of Alzheimer's disease. Neuroimage Clin 16, 343-354.
Binnewijzend MA, Adriaanse SM, Van der Flier WM, Teunissen CE, de Munck JC, Stam CJ, Scheltens P, van Berckel BN, Barkhof F, Wink AM (2014) Brain network alterations in Alzheimer's disease measured by eigenvector centrality in fMRI are related to cognition and CSF biomarkers. Hum Brain Mapp 35, 2383-2393.
Contreras JA, Goni J, Risacher SL, Amico E, Yoder K, Dzemidzic M, West JD, McDonald BC, Farlow MR, Sporns O, Saykin AJ (2017) Cognitive complaints in older adults at risk for Alzheimer's disease are associated with altered resting-state networks. Alzheimers Dement (Amst) 6, 40-49.
Sun Y, Dai Z, Li Y, Sheng C, Li H, Wang X, Chen X, He Y, Han Y (2016) Subjective Cognitive decline: Mapping functional and structural brain changes - A combined restingstate functional and structuralMRimaging study. Radiology 281, 185-192.
Hafkemeijer A, Altmann-Schneider I, Oleksik AM, van de Wiel L, Middelkoop HA, van Buchem MA, van der Grond J, Rombouts SA (2013) Increased functional connectivity and brain atrophy in elderly with subjective memory complaints. Brain Connect 3, 353-362.
Teipel SJ, Cavedo E, Weschke S, Grothe MJ, Rojkova K, Fontaine G, Dauphinot L, Gonzalez-Escamilla G, Potier MC, Bertin H, Habert MO, Dubois B, Hampel H, INSIGHTpreAD study group (2017) Cortical amyloid accumulation is associated with alterations of structural integrity in older people with subjective memory complaints. Neurobiol Aging 57, 143-152.
Agosta F, Pievani M, Geroldi C, Copetti M, Frisoni GB, Filippi M (2012) Resting state fMRI in Alzheimer's disease: Beyond the default mode network. Neurobiol Aging 33, 1564-1578.
Dai Z, Yan C, Li K, Wang Z, Wang J, Cao M, Lin Q, Shu N, Xia M, Bi Y, He Y (2015) Identifying and mapping connectivity patterns of brain network hubs in Alzheimer's disease. Cereb Cortex 25, 3723-3742.
Song J, Qin W, Liu Y, Duan Y, Liu J, He X, Li K, Zhang X, Jiang T, Yu C (2013) Aberrant functional organization within and between resting-state networks in AD. PLoS One 8, e63727.
de Vos F, Koini M, Schouten TM, Seiler S, van der Grond J, Lechner A, Schmidt R, de Rooij M, RomboutsSARB(2018) Acomprehensive analysis of resting state fMRI measures to classify individual patients with Alzheimer's disease. Neuroimage 167, 62-72.
Zhang Z, Liu Y, Jiang T, Zhou B, An N, Dai H, Wang P, Niu Y, Wang L, Zhang X (2012) Altered spontaneous activity in Alzheimer's disease and mild cognitive impairment revealed by regional homogeneity. Neuroimage 59, 1429-1440.