title: Prefrontal control over motor cortex cycles at beta frequency during movement inhibition.
abstract: A fully adapted behavior requires maximum efficiency to inhibit processes in the motor domain. Although a number of cortical and subcortical brain regions have been implicated, converging evidence suggests that activation of right inferior frontal gyrus (r-IFG) and right presupplementary motor area (r-preSMA) is crucial for successful response inhibition. However, it is still unknown how these prefrontal areas convey the necessary signal to the primary motor cortex (M1), the cortical site where the final motor plan eventually has to be inhibited or executed. On the basis of the widely accepted view that brain oscillations are fundamental for communication between neuronal network elements, one would predict that the transmission of these inhibitory signals within the prefrontal-central networks (i.e., r-IFG/M1 and/or r-preSMA/M1) is realized in rapid, periodic bursts coinciding with oscillatory brain activity at a distinct frequency. However, the dynamics of corticocortical effective connectivity has never been directly tested on such timescales. By using double-coil transcranial magnetic stimulation (TMS) and electroencephalography (EEG), we assessed instantaneous prefrontal-to-motor cortex connectivity in a Go/NoGo paradigm as a function of delay from (Go/NoGo) cue onset. In NoGo trials only, the effects of a conditioning prefrontal TMS pulse on motor cortex excitability cycled at beta frequency, coinciding with a frontocentral beta signature in EEG. This establishes, for the first time, a tight link between effective cortical connectivity and related cortical oscillatory activity, leading to the conclusion that endogenous (top-down) inhibitory motor signals are transmitted in beta bursts in large-scale cortical networks for inhibitory motor control.
authors.affiliation: Non-Invasive Brain Stimulation Unit, Clinical and Behavioral Neurology Department, IRCCS Santa Lucia Foundation, Rome 00179, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Picazio
authors.affiliation: Non-Invasive Brain Stimulation Unit, Clinical and Behavioral Neurology Department, IRCCS Santa Lucia Foundation, Rome 00179, Italy; Centre for Cognitive Neuroimaging, Institute of Neuroscience and Psychology, University of Glasgow, Glasgow G12 8QB, UK.
authors.forename: Domenica
authors.initials: D
authors.lastname: Veniero
authors.affiliation: Non-Invasive Brain Stimulation Unit, Clinical and Behavioral Neurology Department, IRCCS Santa Lucia Foundation, Rome 00179, Italy.
authors.forename: Viviana
authors.initials: V
authors.lastname: Ponzo
authors.affiliation: Non-Invasive Brain Stimulation Unit, Clinical and Behavioral Neurology Department, IRCCS Santa Lucia Foundation, Rome 00179, Italy; Department of System Medicine, Tor Vergata University, Rome 00133, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Caltagirone
authors.affiliation: Centre for Cognitive Neuroimaging, Institute of Neuroscience and Psychology, University of Glasgow, Glasgow G12 8QB, UK.
authors.forename: Joachim
authors.initials: J
authors.lastname: Gross
authors.affiliation: Centre for Cognitive Neuroimaging, Institute of Neuroscience and Psychology, University of Glasgow, Glasgow G12 8QB, UK.
authors.forename: Gregor
authors.initials: G
authors.lastname: Thut
authors.affiliation: Non-Invasive Brain Stimulation Unit, Clinical and Behavioral Neurology Department, IRCCS Santa Lucia Foundation, Rome 00179, Italy; Stroke Unit, Department of Neuroscience, Policlinic Tor Vergata, Rome 00133, Italy. Electronic address: g.koch@hsantalucia.it.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Koch
mesh_terms: D000328:Adult; D001611:Beta Rhythm; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D009044:Motor Cortex / Q000502:physiology*; D009068:Movement; D010775:Photic Stimulation; D017397:Prefrontal Cortex / Q000502:physiology*; D009435:Synaptic Transmission; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult