title: Hemispherical asymmetry in human SMA during voluntary simple unilateral movements. An fMRI study.
abstract: Functional magnetic resonance imaging (fMRI) was used to test the hypothesis of a prevailing role of left supplementary motor area (SMA) during voluntary right and left finger movements, in line with subjects' right hand preference. fMRI responses were quantified using task-related percent increase of the signal from statistically activated voxels in primary somatosensory (S1), primary motor (M1), and SMA cortical regions. Regional analysis comprised both extension and intensity of statistically activated groups of voxels. Results replicated previous fMRI evidence. Right M1 and S1 were much more activated during left rather than right movements, whereas such a difference was less evident in left M1 and S1. A novel finding consisted in an analogous functional hemispherical asymmetry in left and right SMA. Strikingly, left SMA activation did not differ statistically during right (contralateral) vs. left (ipsilateral) movements. It was concluded that, in right-handed subjects, left SMA plays a prevailing role in the control of voluntary movements.
authors.affiliation: Dipartimento di Fisiologia Umana e Farmacologia, Sezione di EEG ad alta risoluzione, Università degli Studi di Roma "La Sapienza", Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Babiloni
authors.forename: Filippo
authors.initials: F
authors.lastname: Carducci
authors.forename: Cosimo
authors.initials: C
authors.lastname: Del Gratta
authors.forename: Martina
authors.initials: M
authors.lastname: Demartin
authors.forename: Gian Luca
authors.initials: GL
authors.lastname: Romani
authors.forename: Fabio
authors.initials: F
authors.lastname: Babiloni
authors.forename: Paolo Maria
authors.initials: PM
authors.lastname: Rossini
mesh_terms: D004292:Dominance, Cerebral / Q000502:physiology; D004576:Electromyography; D005385:Fingers / Q000502:physiology; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D009044:Motor Cortex / Q000502:physiology*; D009068:Movement / Q000502:physiology*; D011597:Psychomotor Performance