title: Theta-gamma phase synchronization during memory matching in visual working memory.
abstract: In most cases, object recognition is related to the matching of internal memory contents and bottom-up external sensory stimulation. The aim of this study was to investigate the electrophysiological correlates of memory matching based on EEG oscillatory phase synchronization analysis. Healthy subjects completed a delayed-match to sample task in which items stored in visual-spatial short-term memory had to be compared with a matching or non-matching probe. The results show that memory matching appears as transient phase-synchronization over parieto-occipital regions between theta (4-8 Hz) and high gamma (50-70 Hz) oscillations, 150-200 ms post probe presentation. When memory representation and visual information match, phase-synchronization is stronger in the right hemisphere; conversely, when they do not match, stronger phase synchronization is observed in the left hemisphere. The present results reveal the integrative role of oscillatory activity in the memory matching process.
authors.affiliation: Department of Physiological Psychology, University of Salzburg, Salzburg, Austria.
authors.forename: Elisa Mira
authors.initials: EM
authors.lastname: Holz
authors.forename: Mark
authors.initials: M
authors.lastname: Glennon
authors.forename: Karen
authors.initials: K
authors.lastname: Prendergast
authors.forename: Paul
authors.initials: P
authors.lastname: Sauseng
mesh_terms: D001921:Brain / Q000502:physiology*; D003344:Cortical Synchronization; D004569:Electroencephalography; D005071:Evoked Potentials; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009483:Neuropsychological Tests; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010507:Periodicity; D013826:Theta Rhythm; D013997:Time Factors; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult