title: Being an agent or an observer: different spectral dynamics revealed by MEG.
abstract: Several neuroimaging studies reported that a common set of regions is recruited during action observation and execution and it has been proposed that the modulation of the μ rhythm, in terms of oscillations in the alpha and beta bands might represent the electrophysiological correlate of the underlying brain mechanisms. However, the specific functional role of these bands within the μ rhythm is still unclear. Here, we used magnetoencephalography (MEG) to analyze the spectral and temporal properties of the alpha and beta bands in healthy subjects during an action observation and execution task. We associated the modulation of the alpha and beta power to a broad action observation network comprising several parieto-frontal areas previously detected in fMRI studies. Of note, we observed a dissociation between alpha and beta bands with a slow-down of beta oscillations compared to alpha during action observation. We hypothesize that this segregation is linked to a different sequence of information processing and we interpret these modulations in terms of internal models (forward and inverse). In fact, these processes showed opposite temporal sequences of occurrence: anterior-posterior during action (both in alpha and beta bands) and roughly posterior-anterior during observation (in the alpha band). The observed differentiation between alpha and beta suggests that these two bands might pursue different functions in the action observation and execution processes.
authors.affiliation: Institute for Advanced Biomedical Technologies, G. d'Annunzio University, 66100 Chieti, Italy; Department of Neuroscience, Imaging and Clinical Sciences, G. d'Annunzio University, 66100 Chieti, Italy. Electronic address: v.sebastiani@unich.it.
authors.forename: Valentina
authors.initials: V
authors.lastname: Sebastiani
authors.affiliation: Institute for Advanced Biomedical Technologies, G. d'Annunzio University, 66100 Chieti, Italy; Department of Neuroscience, Imaging and Clinical Sciences, G. d'Annunzio University, 66100 Chieti, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: de Pasquale
authors.affiliation: Institute for Advanced Biomedical Technologies, G. d'Annunzio University, 66100 Chieti, Italy; Department of Neuroscience, Imaging and Clinical Sciences, G. d'Annunzio University, 66100 Chieti, Italy.
authors.forename: Marcello
authors.initials: M
authors.lastname: Costantini
authors.affiliation: Department of Experimental Psychology, University of Oxford, Oxford OX1 3UD, UK; Department of Health Sciences and Technology, ETH Zürich, Switzerland.
authors.forename: Dante
authors.initials: D
authors.lastname: Mantini
authors.affiliation: Institute for Advanced Biomedical Technologies, G. d'Annunzio University, 66100 Chieti, Italy; Department of Neuroscience, Imaging and Clinical Sciences, G. d'Annunzio University, 66100 Chieti, Italy.
authors.forename: Vittorio
authors.initials: V
authors.lastname: Pizzella
authors.affiliation: Institute for Advanced Biomedical Technologies, G. d'Annunzio University, 66100 Chieti, Italy; Department of Neuroscience, Imaging and Clinical Sciences, G. d'Annunzio University, 66100 Chieti, Italy.
authors.forename: Gian Luca
authors.initials: GL
authors.lastname: Romani
authors.affiliation: Institute for Advanced Biomedical Technologies, G. d'Annunzio University, 66100 Chieti, Italy; Department of Neuroscience, Imaging and Clinical Sciences, G. d'Annunzio University, 66100 Chieti, Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Della Penna
mesh_terms: D000328:Adult; D058256:Brain Waves / Q000502:physiology; D002540:Cerebral Cortex / Q000502:physiology*; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D019370:Observation; D055815:Young Adult
keywords: Action observation and execution; Alpha and beta rhythms; Event-related desynchronization (ERD); Internal models; Magnetoencephalography (MEG)