Alterations in gamma frequency oscillations correlate with cortical tau deposition in Alzheimer’s disease

We assessed the relationship of gamma oscillations with tau deposition in Alzheimer’s disease (AD) and other cognitive diseases, as both are altered during the disease course and relate to neurodegeneration. We retrospectively analyzed data from 7 AD, tau positive patients and 9 tau negative patients, that underwent amyloid PET, and cerebral tau PET and EEG within 12 months. Relative gamma power was higher in tau positive (AD) patients than in tau negative patients (p<.05) and tau burden was associated with a linear increase in gamma power (p<.001), while no association was present with amyloid-β burden. Thus, increase in the gamma power might represent a novel biomarker for tau driven neurodegeneration. ### Competing Interest Statement The Centre de la memoire is funded by the following private donors under the supervision of the Private Foundation of Geneva University Hospitals: A.P.R.A. - Association Suisse pour la Recherche sur la Maladie d Alzheimer, Geneve; Fondation Segre, Geneve; Race Against Dementia Foundation, London, UK; Fondation Child Care, Geneve; Fondation Edmond J. Safra, Geneve; FondationMinkoff, Geneve; Fondazione Agusta, Lugano; McCall Macbain Foundation, Canada; Nicole et Rene Keller, Geneve; Fondation AETAS, Geneve. MS and SV are scientific advisors and shareholders of Epilog NV, Ghent. VG received financial support for research and/or speaker fees through her institution from Siemens Healthineers, GE Healthcare ### Funding Statement The Centre de la memoire is funded by the following private donors under the supervision of the Private Foundation of Geneva University Hospitals: A.P.R.A. - Association Suisse pour la Recherche sur la Maladie d Alzheimer, Geneve; Fondation Segre, Geneve; Race Against Dementia Foundation, London, UK; Fondation Child Care, Geneve; Fondation Edmond J. Safra, Geneve; FondationMinkoff, Geneve; Fondazione Agusta, Lugano; McCall Macbain Foundation, Canada; Nicole et Rene Keller, Geneve; Fondation AETAS, Geneve. The work of IR has been supported by the Swiss National Science Foundation (SNSF) grant no. 192749 and CRSII5\_209470 awarded to SV. MS was supported by the Swiss National Science Foundation project 180365. VG was supported by the Swiss National Science Foundation (projects 320030\_169876, 320030\_185028 and IZSEZ0\_188355), by the Velux foundation (project 1123), by the Schmidheiny foundation, and by the Aetas foundation. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The ethic committee of the canton of Geneva (Commission cantonale d'ethique de la recherche CCER) gave ethical approval for this work (PB_2016-01382 (15-206)). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Data included in the manuscript are not sharable as patients did not consent to it. * AD : Alzheimer’s disease PET : positron emission tomography SUVr : standard uptake value ratio EEG : electroencephalography Aβ42 : amyloid-beta 42