title: Independent Causal Contributions of Alpha- and Beta-Band Oscillations during Movement Selection.
abstract: To select a movement, specific neuronal populations controlling particular features of that movement need to be activated, whereas other populations are downregulated. The selective (dis)inhibition of cortical sensorimotor populations is governed by rhythmic neural activity in the alpha (8-12 Hz) and beta (15-25 Hz) frequency range. However, it is unclear whether and how these rhythms contribute independently to motor behavior. Building on a recent dissociation of the sensorimotor alpha- and beta-band rhythms, we test the hypothesis that the beta-band rhythm governs the disinhibition of task-relevant neuronal populations, whereas the alpha-band rhythm suppresses neurons that may interfere with task performance. Cortical alpha- and beta-band rhythms were manipulated with transcranial alternating current stimulation (tACS) while human participants selected how to grasp an object. Stimulation was applied at either 10 or 20 Hz and was imposed on the sensorimotor cortex contralaterally or ipsilaterally to the grasping hand. In line with task-induced changes in endogenous spectral power, the effect of the tACS intervention depended on the frequency and site of stimulation. Whereas tACS stimulation generally increased movement selection times, 10 Hz stimulation led to relatively faster selection times when applied to the hemisphere ipsilateral to the grasping hand, compared with other stimulation conditions. These effects occurred selectively when multiple movements were considered. These observations functionally differentiate the causal contribution of alpha- and beta-band oscillations to movement selection. The findings suggest that sensorimotor beta-band rhythms disinhibit task-relevant populations, whereas alpha-band rhythms inhibit neuronal populations that could interfere with movement selection.
  
  
  
  This study shows dissociable effects of 10 Hz and 20 Hz tACS on the duration of movement selection. These observations have two elements of general relevance. First, the finding that alpha- and beta-band oscillations contribute independently to movement selection provides insight in how oscillations orchestrate motor behavior, which is key to understand movement selection deficits in neurodegenerative disorders. Second, the findings highlight the potential of 10 Hz stimulation as a neurophysiologically grounded intervention to enhance human performance. In particular, this intervention can potentially be exploited to boost rehabilitation after neural damage by targeting the unaffected hemisphere.
authors.affiliation: Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Cognitive Neuroimaging, 6500 HB Nijmegen, The Netherlands, loek.brinkman@gmail.com.
authors.forename: Loek
authors.identifier: 0000-0003-3997-1173
authors.initials: L
authors.lastname: Brinkman
authors.affiliation: Helen Wills Neuroscience Institute, University of California, Berkeley, California 94720, and.
authors.forename: Arjen
authors.identifier: 0000-0003-3798-4923
authors.initials: A
authors.lastname: Stolk
authors.affiliation: Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Cognitive Neuroimaging, 6500 HB Nijmegen, The Netherlands.
authors.forename: Tom R
authors.initials: TR
authors.lastname: Marshall
authors.affiliation: Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Cognitive Neuroimaging, 6500 HB Nijmegen, The Netherlands.
authors.forename: Sophie
authors.initials: S
authors.lastname: Esterer
authors.affiliation: Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Cognitive Neuroimaging, 6500 HB Nijmegen, The Netherlands.
authors.forename: Poppy
authors.identifier: 0000-0002-1985-292X
authors.initials: P
authors.lastname: Sharp
authors.affiliation: Utrecht University, Helmholz Institute, Experimental Psychology, 3584 CS Utrecht, The Netherlands.
authors.forename: H Chris
authors.initials: HC
authors.lastname: Dijkerman
authors.affiliation: Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Cognitive Neuroimaging, 6500 HB Nijmegen, The Netherlands.
authors.forename: Floris P
authors.initials: FP
authors.lastname: de Lange
authors.affiliation: Radboud University Nijmegen, Donders Institute for Brain, Cognition and Behaviour, Donders Centre for Cognitive Neuroimaging, 6500 HB Nijmegen, The Netherlands.
authors.forename: Ivan
authors.initials: I
authors.lastname: Toni
mesh_terms: D000328:Adult; D000513:Alpha Rhythm / Q000502:physiology*; D000704:Analysis of Variance; D001611:Beta Rhythm / Q000502:physiology*; D002540:Cerebral Cortex / Q000502:physiology*; D002755:Choice Behavior / Q000502:physiology*; D004569:Electroencephalography; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology*; D010507:Periodicity; D065908:Transcranial Direct Current Stimulation; D055815:Young Adult
keywords: alpha beta oscillations; motor imagery; movement selection; noninvasive brain stimulation; sensorimotor