Cortical sources of resting state EEG rhythms are related to brain hypometabolism in subjects with Alzheimer's disease: an EEG-PET study.


Author: Babiloni C1, Del Percio C2, Caroli A3, Salvatore E4, Nicolai E2, Marzano N5, Lizio R6, Cavedo E7, Landau S8, Chen K9, Jagust W10, Reiman E9, Tedeschi G11, Montella P11, De Stefano M11, Gesualdo L12, Frisoni GB13, Soricelli A14

Affiliation: <sup>1</sup>Department of Human Physiology and Pharmacology "Erspamer", University of Rome " La Sapienza", Rome, Italy; Institute for Research and Medical Care, IRCCS San Raffaele Pisana, Rome, Italy.

<sup>2</sup>Department of Integrated Imaging, IRCCS SDN, Napoli, Italy.

<sup>3</sup>Medical Imaging Unit, IRCCS Istituto di Ricerche Farmacologiche Mario Negri, Bergamo, Italy.

<sup>4</sup>Department of Neurosciences, Reproductive Sciences and Odontostomatology, University of Naples Federico II, Naples, Italy.

<sup>5</sup>Department of Human Physiology and Pharmacology "Erspamer", University of Rome " La Sapienza", Rome, Italy.

<sup>6</sup>Department of Human Physiology and Pharmacology "Erspamer", University of Rome " La Sapienza", Rome, Italy. Electronic address: roberta.lizio@uniroma1.it.

<sup>7</sup>LENITEM Laboratory of Epidemiology, Neuroimaging, and Telemedicine, IRCCS Istituto Centro San Giovanni di Dio-Fatebenefratelli, Brescia, Italy; Cognition, Neuroimaging and Brain Diseases Laboratory, Centre de Recherche de l'Institut du Cerveau et de la Moelle Épiniére (CRICM-UMRS 975), Université Pierre et Marie Curie-Paris 6, Paris, France.

<sup>8</sup>Helen Wills Neuroscience Institute, University of California, Berkeley, CA, USA.

<sup>9</sup>Banner Alzheimer's Institute, Phoenix, AZ, USA.

<sup>10</sup>Helen Wills Neuroscience Institute, University of California, Berkeley, CA, USA; Department of Neurological Sciences, Second University of Naples, Naples, Italy.

<sup>11</sup>Department of Neurological Sciences, Second University of Naples, Naples, Italy.

<sup>12</sup>Dipartimento Emergenza e Trapianti d'Organi (D.E.T.O), University of Bari, Bari, Italy.

<sup>13</sup>LENITEM Laboratory of Epidemiology, Neuroimaging, and Telemedicine, IRCCS Istituto Centro San Giovanni di Dio-Fatebenefratelli, Brescia, Italy; Memory Clinic and LANVIE - Laboratory of Neuroimaging of Aging, University Hospitals and University of Geneva, Geneva, Switzerland.

<sup>14</sup>Department of Integrated Imaging, IRCCS SDN, Napoli, Italy; Department of Motor Sciences and Healthiness, University of Naples Parthenope, Naples, Italy.
Conference/Journal: Neurobiol Aging.
Date published: 2016 Aug 31
Other:
 Volume ID: 48   ,  Pages: 122-134   ,  Special Notes: doi: 10.1016/j.neurobiolaging.2016.08.021. [Epub ahead of print]   ,  Word Count: 258  
    Cortical sources of resting state electroencephalographic (EEG) delta (2-4 Hz) and low-frequency alpha (8-10.5 Hz) rhythms show abnormal activity (i.e., current density) in patients with dementia due to Alzheimer's disease (AD). Here, we hypothesized that abnormality of this activity is related to relevant disease processes as revealed by cortical hypometabolism typically observed in AD patients by fluorodeoxyglucose positron emission tomography. Resting state eyes-closed EEG data were recorded in 19 AD patients with dementia and 40 healthy elderly (Nold) subjects. EEG frequency bands of interest were delta and low-frequency alpha. EEG sources were estimated in these bands by low-resolution brain electromagnetic tomography (LORETA). Fluorodeoxyglucose positron emission tomography images were recorded only in the AD patients, and cortical hypometabolism was indexed by the so-called Alzheimer's discrimination analysis tool (PALZ) in the frontal association, ventromedial frontal, temporoparietal association, posterior cingulate, and precuneus areas. Results showed that compared with the Nold group, the AD group pointed to higher activity of delta sources and lower activity of low-frequency alpha sources in a cortical region of interest formed by all cortical areas of the PALZ score. In the AD patients, there was a positive correlation between the PALZ score and the activity of delta sources in the cortical region of interest (p < 0.05). These results suggest a relationship between resting state cortical hypometabolism and synchronization of cortical neurons at delta rhythms in AD patients with dementia.



Copyright © 2016 Elsevier Inc. All rights reserved.



KEYWORDS: Alzheimer's disease (AD); Brain hypometabolism; Electroencephalography (EEG); Fluorodeoxyglucose positron emission tomography (FDG-PET); Low resolution brain electromagnetic tomography (LORETA)



PMID: 27668356  DOI: 10.1016/j.neurobiolaging.2016.08.021