title: Alpha- and beta-band oscillations subserve different processes in reactive control of limb movements.
abstract: The capacity to rapidly suppress a behavioral act in response to sudden instruction to stop is a key cognitive function. This function, called reactive control, is tested in experimental settings using the stop signal task, which requires subjects to generate a movement in response to a go signal or suppress it when a stop signal appears. The ability to inhibit this movement fluctuates over time: sometimes, subjects can stop their response, and at other times, they can not. To determine the neural basis of this fluctuation, we recorded local field potentials (LFPs) in the alpha (6-12 Hz) and beta (13-35 Hz) bands from the dorsal premotor cortex of two nonhuman primates that were performing the task. The ability to countermand a movement after a stop signal was predicted by the activity of both bands, each purportedly representing a distinct neural process. The beta band represents the level of movement preparation; higher beta power corresponds to a lower level of movement preparation, whereas the alpha band supports a proper phasic, reactive inhibitory response: movements are inhibited when alpha band power increases immediately after a stop signal. Our findings support the function of LFP bands in generating the signatures of various neural computations that are multiplexed in the brain.
authors.affiliation: Department Physiology and Pharmacology, Sapienza University of Rome Rome, Italy.
authors.forename: Pierpaolo
authors.initials: P
authors.lastname: Pani
authors.affiliation: Department Physiology and Pharmacology, Sapienza University of Rome Rome, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Di Bello
authors.affiliation: Department Physiology and Pharmacology, Sapienza University of Rome Rome, Italy.
authors.forename: Emiliano
authors.initials: E
authors.lastname: Brunamonti
authors.affiliation: Department Physiology and Pharmacology, Sapienza University of Rome Rome, Italy ; Center for Neuroscience and Cognitive Systems@UniTn, Istituto Italiano di Tecnologia Rovereto (TN), Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: D'Andrea
authors.affiliation: Department Physiology and Pharmacology, Sapienza University of Rome Rome, Italy.
authors.forename: Odysseas
authors.initials: O
authors.lastname: Papazachariadis
authors.affiliation: Department Physiology and Pharmacology, Sapienza University of Rome Rome, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Ferraina
keywords: alpha-band; beta-band; cognitive control; dorsal premotor cortex; monkey; movement inhibition; reaching; stop task