title: Occipital sources of resting-state alpha rhythms are related to local gray matter density in subjects with amnesic mild cognitive impairment and Alzheimer's disease.
abstract: Occipital sources of resting-state electroencephalographic (EEG) alpha rhythms are abnormal, at the group level, in patients with amnesic mild cognitive impairment (MCI) and Alzheimer's disease (AD). Here, we evaluated the hypothesis that amplitude of these occipital sources is related to neurodegeneration in occipital lobe as measured by magnetic resonance imaging. Resting-state eyes-closed EEG rhythms were recorded in 45 healthy elderly (Nold), 100 MCI, and 90 AD subjects. Neurodegeneration of occipital lobe was indexed by weighted averages of gray matter density, estimated from structural MRIs. EEG rhythms of interest were alpha 1 (8-10.5 Hz) and alpha 2 (10.5-13 Hz). EEG cortical sources were estimated by low-resolution brain electromagnetic tomography. Results showed a positive correlation between occipital gray matter density and amplitude of occipital alpha 1 sources in Nold, MCI, and AD subjects as a whole group (r = 0.3, p = 0.000004, N = 235). Furthermore, there was a positive correlation between the amplitude of occipital alpha 1 sources and cognitive status as revealed by Mini Mental State Examination score across all subjects (r = 0.38, p = 0.000001, N = 235). Finally, amplitude of occipital alpha 1 sources allowed a moderate classification of individual Nold and AD subjects (sensitivity: 87.8%; specificity: 66.7%; area under the receiver operating characteristic curve: 0.81). These results suggest that the amplitude of occipital sources of resting-state alpha rhythms is related to AD neurodegeneration in occipital lobe along pathologic aging.
authors.affiliation: Department of Physiology and Pharmacology, University of Rome "La Sapienza", Rome, Italy; Department of Neuroscience, IRCCS San Raffaele Pisana, Rome, Italy. Electronic address: claudio.babiloni@uniroma1.it.
authors.forename: Claudio
authors.initials: C
authors.lastname: Babiloni
authors.affiliation: Department of Neuroscience, IRCCS San Raffaele Pisana, Rome, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Del Percio
authors.affiliation: LENITEM (Laboratory of Epidemiology, Neuroimaging and Telemedicine), IRCCS Centro "S. Giovanni di Dio-F.B.F.", Brescia, Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Boccardi
authors.affiliation: Department of Neuroscience, IRCCS San Raffaele Pisana, Rome, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Lizio
authors.affiliation: Department of Physiology and Pharmacology, University of Rome "La Sapienza", Rome, Italy.
authors.forename: Susanna
authors.initials: S
authors.lastname: Lopez
authors.affiliation: Department of Physiology and Pharmacology, University of Rome "La Sapienza", Rome, Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: Carducci
authors.affiliation: Department of Integrated Imaging, IRCCS SDN, Napoli, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Marzano
authors.affiliation: Department of Integrated Imaging, IRCCS SDN, Napoli, Italy; Department of Studies of Institutions and Territorial Systems, University of Naples Parthenope, Naples, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Soricelli
authors.affiliation: Department of Neurology, IRCCS Oasi Institute for Research on Mental Retardation and Brain Aging, Troina, Enna, Italy.
authors.forename: Raffaele
authors.initials: R
authors.lastname: Ferri
authors.affiliation: Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy.
authors.forename: Antonio Ivano
authors.initials: AI
authors.lastname: Triggiani
authors.affiliation: LENITEM (Laboratory of Epidemiology, Neuroimaging and Telemedicine), IRCCS Centro "S. Giovanni di Dio-F.B.F.", Brescia, Italy.
authors.forename: Annapaola
authors.initials: A
authors.lastname: Prestia
authors.affiliation: Department of Informatics and Systems "Antonio Ruberti", University of Rome "La Sapienza", Rome, Italy.
authors.forename: Serenella
authors.initials: S
authors.lastname: Salinari
authors.affiliation: Centre for Translational Neuroscience & Mental Health Research, The University of Newcastle, Newcastle, New South Wales, Australia; Schizophrenia Research Institute, Darlinghurst, New South Wales, Australia.
authors.forename: Paul E
authors.initials: PE
authors.lastname: Rasser
authors.affiliation: Brain Dynamics, Cognition and Complex Systems Research Center, Istanbul Kültür University, Istanbul, Turkey.
authors.forename: Erol
authors.initials: E
authors.lastname: Basar
authors.affiliation: Department of Neuroscience (DINOGMI), Clinical Neurology, University of Genoa, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Famà
authors.affiliation: Department of Neuroscience (DINOGMI), Clinical Neurology, University of Genoa, Italy.
authors.forename: Flavio
authors.initials: F
authors.lastname: Nobili
authors.affiliation: Brain Dynamics, Cognition and Complex Systems Research Center, Istanbul Kültür University, Istanbul, Turkey; Department of Neurosciences, Dokuz Eylül University, Izmir, Turkey; Brain Dynamics Multidisciplinary Research Center, Dokuz Eylül University, Izmir, Turkey; Department of Neurology, Dokuz Eylül University Medical School, Izmir, Turkey.
authors.forename: Görsev
authors.initials: G
authors.lastname: Yener
authors.affiliation: Brain Dynamics, Cognition and Complex Systems Research Center, Istanbul Kültür University, Istanbul, Turkey; Department of Neurosciences, Dokuz Eylül University, Izmir, Turkey.
authors.forename: Derya Durusu
authors.initials: DD
authors.lastname: Emek-Savaş
authors.affiliation: Dipartimento Emergenza e Trapianti d'Organi (D.E.T.O), University of Bari, Bari, Italy.
authors.forename: Loreto
authors.initials: L
authors.lastname: Gesualdo
authors.affiliation: Department of Neurology, Ospedali Riuniti, Foggia, Italy.
authors.forename: Ciro
authors.initials: C
authors.lastname: Mundi
authors.affiliation: Department of Neurology & Psychiatry, Imaging Genetics Center, Laboratory of Neuro Imaging, UCLA School of Medicine, Los Angeles, CA, USA.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Thompson
authors.affiliation: Department of Neuroscience, IRCCS San Raffaele Pisana, Rome, Italy; Department of Geriatrics, Neuroscience & Orthopedics, Institute of Neurology, Catholic University, Rome, Italy.
authors.forename: Paolo M
authors.initials: PM
authors.lastname: Rossini
authors.affiliation: LENITEM (Laboratory of Epidemiology, Neuroimaging and Telemedicine), IRCCS Centro "S. Giovanni di Dio-F.B.F.", Brescia, Italy.
authors.forename: Giovanni B
authors.initials: GB
authors.lastname: Frisoni
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000473:pathology* / Q000503:physiopathology*; D060825:Cognitive Dysfunction / Q000473:pathology* / Q000503:physiopathology*; D004569:Electroencephalography; D005260:Female; D066128:Gray Matter / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests; D009778:Occipital Lobe / Q000503:physiopathology*; D012146:Rest / Q000502:physiology*
keywords: Alzheimer's disease (AD); Electroencephalography (EEG); Gray matter density (GMD); Magnetic resonance imaging (MRI); Mild cognitive impairment (MCI)