title: Intrinsic patterns of coupling between correlation and amplitude of low-frequency fMRI fluctuations are disrupted in degenerative dementia mainly due to functional disconnection.
abstract: Low frequency fluctuations (LFFs) of the BOLD signal are a major discovery in the study of the resting brain with functional magnetic resonance imaging (fMRI). Two fMRI-based measures, functional connectivity (FC), a measure of signal synchronicity, and the amplitude of LFFs (ALFF), a measure of signal periodicity, have been proved to be sensitive to changes induced by several neurological diseases, including degenerative dementia. In spite of the increasing use of these measures, whether and how they are related to each other remains to be elucidated. In this work we used voxel-wise FC and ALFF computed in different frequency bands (slow-5: 0.01-0.027 Hz; slow-4: 0.027-0.073 Hz; and full-band: 0.01-0.073 Hz), in order to assess their relationship in healthy elderly as well as the relevant changes induced by Alzheimer's Disease (AD) and Mild Cognitive Impairment (MCI). We found that in healthy elderly subjects FC and ALFF are positively correlated in anterior and posterior cingulate cortex (full-band, slow-4 and slow-5), temporal cortex (full-band and slow-5), and in a set of subcortical regions (full-band and slow-4). These correlation patterns between FC and ALFF were absent in either AD or MCI patients. Notably, the loss of correlation between FC and ALFF in the AD group was primarily due to changes in FC rather than in ALFF. Our results indicate that degenerative dementia is characterized by a loss of global connection rather than by a decrease of fluctuation amplitude.
authors.affiliation: Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi, Rome, Italy; Dipartimento di Fisica, Sapienza Università di Roma, Rome, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Mascali
authors.affiliation: Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi, Rome, Italy; Dipartimento di Fisica, Sapienza Università di Roma, Rome, Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: DiNuzzo
authors.affiliation: Fondazione Santa Lucia IRCCS, Rome, Italy.
authors.forename: Tommaso
authors.initials: T
authors.lastname: Gili
authors.affiliation: Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi, Rome, Italy; Fondazione Santa Lucia IRCCS, Rome, Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Moraschi
authors.affiliation: Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi, Rome, Italy; Dipartimento di Scienze, Università degli Studi Roma Tre, Rome, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Fratini
authors.affiliation: Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi, Rome, Italy; Fondazione Santa Lucia IRCCS, Rome, Italy.
authors.forename: Bruno
authors.initials: B
authors.lastname: Maraviglia
authors.affiliation: Fondazione Santa Lucia IRCCS, Rome, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Serra
authors.affiliation: Fondazione Santa Lucia IRCCS, Rome, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Bozzali
authors.affiliation: Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi, Rome, Italy; Fondazione Santa Lucia IRCCS, Rome, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Giove
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000503:physiopathology*; D001921:Brain / Q000473:pathology*; D060825:Cognitive Dysfunction / Q000503:physiopathology*; D063132:Connectome; D003704:Dementia / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged
references.citation: Biomed Res Int. 2014;2014:920902
references.pmid: 24822220
references.citation: Eur Neuropsychopharmacol. 2010 Aug;20(8):519-34
references.pmid: 20471808
references.citation: Neuroimage. 2007 Aug 1;37(1):90-101
references.pmid: 17560126
references.citation: Magn Reson Imaging. 2008 Sep;26(7):1055-64
references.pmid: 18657923
references.citation: Neuroimage. 2006 Jun;31(2):496-504
references.pmid: 16473024
references.citation: Front Hum Neurosci. 2013 Apr 02;7:118
references.pmid: 23565090
references.citation: J Alzheimers Dis. 2014;40(2):387-97
references.pmid: 24473186
references.citation: Chin Med J (Engl). 2013;126(15):2912-7
references.pmid: 23924467
references.citation: Nat Rev Neurosci. 2007 Sep;8(9):700-11
references.pmid: 17704812
references.citation: Neuroimage. 2013 Oct 15;80:349-59
references.pmid: 23571418
references.citation: Neuroimage. 2011 Mar 1;55(1):8-23
references.pmid: 21111053
references.citation: Hum Brain Mapp. 2014 Jan;35(1):331-9
references.pmid: 22987723
references.citation: Neuroimage. 2010 Jan 15;49(2):1432-45
references.pmid: 19782143
references.citation: Hum Brain Mapp. 2008 Jul;29(7):740-50
references.pmid: 18438886
references.citation: J Alzheimers Dis. 2013;33(4):1157-65
references.pmid: 23109557
references.citation: Proc Natl Acad Sci U S A. 2007 Nov 20;104(47):18760-5
references.pmid: 18003904
references.citation: J Neurosci. 2011 Nov 30;31(48):17680-8
references.pmid: 22131428
references.citation: PLoS One. 2012;7(3):e32766
references.pmid: 22412922
references.citation: Cereb Cortex. 2013 Feb;23(2):255-63
references.pmid: 22345358
references.citation: PLoS One. 2012;7(5):e37828
references.pmid: 22666397
references.citation: Curr Alzheimer Res. 2014 May;11(4):389-98
references.pmid: 24720892
references.citation: Neuroimage. 2004 Feb;21(2):757-67
references.pmid: 14980579
references.citation: Hum Brain Mapp. 2014 Feb;35(2):627-37
references.pmid: 23125131
references.citation: J Neurophysiol. 2011 Dec;106(6):3010-8
references.pmid: 21917999
references.citation: Arch Neurol. 2001 Dec;58(12):1985-92
references.pmid: 11735772
references.citation: Neuroimage. 2009 Feb 1;44(3):857-69
references.pmid: 18951982
references.citation: Neuroimage. 2004 Apr;21(4):1652-64
references.pmid: 15050588
references.citation: J Neurol Neurosurg Psychiatry. 2011 Jan;82(1):58-66
references.pmid: 20639384
references.citation: Proc Natl Acad Sci U S A. 2004 Mar 30;101(13):4637-42
references.pmid: 15070770
references.citation: Neuroimage. 2012 Apr 2;60(2):1426-39
references.pmid: 22245357
references.citation: PLoS Biol. 2008 Jul 1;6(7):e159
references.pmid: 18597554
references.citation: Neuroimage. 2006 Jul 15;31(4):1536-48
references.pmid: 16632379
references.citation: J Neurosci. 2011 May 25;31(21):7910-9
references.pmid: 21613505
references.citation: Int J Psychophysiol. 2008 Mar;67(3):242-51
references.pmid: 17707538
references.citation: PLoS One. 2014;9(1):e86818
references.pmid: 24466256
references.citation: Neuron. 2007 Oct 4;56(1):171-84
references.pmid: 17920023
references.citation: PLoS One. 2009;4(5):e5743
references.pmid: 19492040
references.citation: Neuroimage. 2010 Feb 15;49(4):3132-48
references.pmid: 19909818
references.citation: J Neurosci. 2014 Jan 8;34(2):356-62
references.pmid: 24403137
references.citation: Proc Natl Acad Sci U S A. 2003 Sep 16;100(19):11053-8
references.pmid: 12958209
references.citation: Hum Brain Mapp. 2011 Oct;32(10):1720-40
references.pmid: 21077137
references.citation: Proc Natl Acad Sci U S A. 2010 Jun 1;107(22):10238-43
references.pmid: 20439733
references.citation: Neuroimage. 2005 Jul 1;26(3):839-51
references.pmid: 15955494
references.citation: Front Syst Neurosci. 2010 Jun 17;4:19
references.pmid: 20592951
references.citation: Radiology. 2010 Aug;256(2):598-606
references.pmid: 20656843
references.citation: PLoS One. 2012;7(2):e28664
references.pmid: 22319555
references.citation: Behav Brain Res. 2013 Sep 1;252:18-23
references.pmid: 23727173
references.citation: Chin Med J (Engl). 2012 Mar;125(5):858-62
references.pmid: 22490587
references.citation: Neuroimage. 2011 Mar 1;55(1):287-95
references.pmid: 21118724
references.citation: Science. 2004 Jun 25;304(5679):1926-9
references.pmid: 15218136
references.citation: Cereb Cortex. 2008 Dec;18(12):2735-47
references.pmid: 18400794
references.citation: Radiology. 2002 Oct;225(1):253-9
references.pmid: 12355013
references.citation: Brain Connect. 2012;2(3):125-41
references.pmid: 22642651
references.citation: Magn Reson Imaging. 2007 Dec;25(10):1358-69
references.pmid: 17482411
references.citation: Comput Biomed Res. 1996 Jun;29(3):162-73
references.pmid: 8812068
references.citation: Brain Dev. 2007 Mar;29(2):83-91
references.pmid: 16919409
references.citation: Neurology. 1984 Jul;34(7):939-44
references.pmid: 6610841
references.citation: Neuroimage. 2007 Apr 1;35(2):488-500
references.pmid: 17254803
references.citation: J Neurosci. 2009 Feb 11;29(6):1860-73
references.pmid: 19211893
references.citation: Philos Trans R Soc Lond B Biol Sci. 2005 May 29;360(1457):1001-13
references.pmid: 16087444
references.citation: Neuroimage. 2001 Dec;14(6):1238-43
references.pmid: 11707080
references.citation: Proc Natl Acad Sci U S A. 2013 Aug 13;110(33):13642-7
references.pmid: 23898179
references.citation: Magn Reson Med. 1995 Oct;34(4):537-41
references.pmid: 8524021