title: Role of the dorsal premotor cortex in rhythmic auditory-motor entrainment: a perturbational approach by rTMS.
abstract: Synchronization of body movements to an external beat is a universal human ability, which has also been recently documented in nonhuman species. The neural substrates of this rhythmic motor entrainment are still under investigation. Correlational neuroimaging data suggest an involvement of the dorsal premotor cortex (dPMC) and the supplementary motor area (SMA). In 14 healthy volunteers, we more specifically investigated the neural network underlying this phenomenon using a causal approach by an established 1-Hz repetitive transcranial magnetic stimulation (rTMS) protocol, which produces a focal suppression of cortical excitability outlasting the stimulation period. Synchronization accuracy between rhythmic cues and right index finger tapping, as measured by the mean time lag (asynchrony) between motor and auditory events, was significantly affected when the right dPMC function was transiently perturbed by "off-line" focal rTMS, whereas the reproduction of the rhythmic sequence per se (inter-tap-interval) was spared. This approach affected metrical rhythms of different complexity, but not non-metrical or isochronous sequences. Conversely, no change in auditory-motor synchronization was observed with rTMS of the SMA, of the left dPMC or over a control site (midline occipital area). Our data strongly support the view that the right dPMC is crucial for rhythmic auditory-motor synchronization in humans.
authors.affiliation: Unità Operativa di Neurologia, Azienda Sanitaria di Firenze, Ospedale San Giovanni di Dio,Firenze, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Giovannelli
authors.forename: Iglis
authors.initials: I
authors.lastname: Innocenti
authors.forename: Simone
authors.initials: S
authors.lastname: Rossi
authors.forename: Alessandra
authors.initials: A
authors.lastname: Borgheresi
authors.forename: Aldo
authors.initials: A
authors.lastname: Ragazzoni
authors.forename: Gaetano
authors.initials: G
authors.lastname: Zaccara
authors.forename: Maria Pia
authors.initials: MP
authors.lastname: Viggiano
authors.forename: Massimo
authors.initials: M
authors.lastname: Cincotta
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D000704:Analysis of Variance; D003463:Cues; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D009044:Motor Cortex / Q000502:physiology*; D010507:Periodicity; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult