1 Title: Two spatially distinct posterior alpha sources fulfill different functional roles in attention Abbreviated title: Two posterior alpha sources control attention Author names and affiliations: R. Sokoliuk 1 , S.D. Mayhew 1 , K.M. Aquino 2,3 , R. Wilson 1 , M.J. Brookes 2 , S.T. Francis 2 , S. Hanslmayr 1 , K.J. Mullinger 1, 2 1: Centre for Human Brain Health (CHBH), School of Psychology, University of Birmingham, UK; 2: Sir Peter Mansfield Imaging Centre (SPMIC), School of Physics and Astronomy, University of Nottingham, UK 3: Monash University, Melbourne, Australia Corresponding author: Rodika Sokoliuk r.sokoliuk@bham.ac.uk University of Birmingham School of Psychology B15 2TT, Edgbaston, Birmingham, UK Number of pages: 31 Number of figures: 5 Number of words: - Abstract: 250/250 - Significance statement: 120/120 - Introduction: 639/650 - Discussion: 1498/1500 Conflict of interest: The authors claim no conflict of interest. Acknowledgements: This research was funded by a Leverhulme Trust Research Project Grant to KJM. . CC-BY-NC-ND 4.0 International license not certified by peer review) is the author/funder. It is made available under a The copyright holder for this preprint (which was this version posted August 3, 2018. . https://doi.org/10.1101/384065 doi: bioRxiv preprint