title: Motor imagery-based brain activity parallels that of motor execution: evidence from magnetic source imaging of cortical oscillations.
abstract: Motor imagery (MI) is a form of practice in which an individual mentally performs a motor task. Previous research suggests that skill acquisition via MI is facilitated by repetitive activation of brain regions in the sensorimotor network similar to that of motor execution, however this evidence is conflicting. Further, many studies do not control for overt muscle activity and thus the activation patterns reported for MI may be driven in part by actual movement. The purpose of the current research is to further establish MI as a secondary modality of skill acquisition by providing electrophysiological evidence of an overlap between brain areas recruited for motor execution and imagery. Non-disabled participants (N=18; 24.7±3.8 years) performed both execution and imagery of a unilateral sequence button-press task. Magnetoencephalography (MEG) was utilized to capture neural activity, while electromyography used to rigorously monitor muscle activity. Event-related synchronization/desynchronization (ERS/ERD) analysis was conducted in the beta frequency band (15-30 Hz). Whole head dual-state beamformer analysis was applied to MEG data and 3D t-tests were conducted after Talairach normalization. Source-level analysis showed that MI has similar patterns of spatial activity as ME, including activation of contralateral primary motor and somatosensory cortices. However, this activation is significantly less intense during MI (p<0.05). As well, activation during ME was more lateralized (i.e., within the contralateral hemisphere). These results confirm that ME and MI have similar spatial activation patterns. Thus, the current research provides direct electrophysiological evidence to further establish MI as a secondary form of skill acquisition.
authors.affiliation: Laboratory for Brain Recovery and Function, Dalhousie University, Halifax, NS, Canada; Department of Psychology and Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: Sarah
authors.initials: S
authors.lastname: Kraeutner
authors.affiliation: Laboratory for Brain Recovery and Function, Dalhousie University, Halifax, NS, Canada; School of Physiotherapy, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: Alicia
authors.initials: A
authors.lastname: Gionfriddo
authors.affiliation: School of Physiotherapy, Dalhousie University, Halifax, Nova Scotia, Canada; Biomedical Translational Imaging Centre (BIOTIC), IWK Health Sciences Centre, Halifax, Nova Scotia, Canada.
authors.forename: Timothy
authors.initials: T
authors.lastname: Bardouille
authors.affiliation: Laboratory for Brain Recovery and Function, Dalhousie University, Halifax, NS, Canada; Department of Psychology and Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada; School of Physiotherapy, Dalhousie University, Halifax, Nova Scotia, Canada. Electronic address: s.boe@dal.ca.
authors.forename: Shaun
authors.initials: S
authors.lastname: Boe
mesh_terms: D001611:Beta Rhythm; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D004576:Electromyography; D005071:Evoked Potentials; D005260:Female; D006225:Hand / Q000502:physiology; D006801:Humans; D007092:Imagination / Q000502:physiology*; D007858:Learning / Q000502:physiology; D015225:Magnetoencephalography; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D009483:Neuropsychological Tests; D011597:Psychomotor Performance / Q000502:physiology*; D012815:Signal Processing, Computer-Assisted; D014741:Video Recording; D055815:Young Adult
keywords: Magnetoencephalography; Motor imagery; Motor learning; Neuroimaging