title: Does comprehension of symbolic gestures and corresponding-in-meaning words make use of motor simulation?
abstract: The present study aimed at determining whether or not the comprehension of symbolic gestures, and corresponding-in-meaning words, makes use of cortical circuits involved in movement execution control. Participants were presented with videos of an actress producing meaningful or meaningless gestures, pronouncing corresponding-in-meaning words or pseudo-words; they were required to judge whether the signal was meaningful or meaningless. Single pulse TMS was applied to forearm primary motor cortex area 150-200 ms after the point when the stimulus meaning could be understood. MEPs were significantly greater when processing meaningless signals as compared to a baseline condition presenting a still-and-silent actress. In contrast, this was not the case for meaningful signals whose motor activation did not differ from that for the baseline stimulus. MEPs were significantly greater for meaningless than meaningful signals and no significant difference was found between gesture and speech. On the basis of these results, we hypothesized that the observation-of/listening-to meaningless signals recruits motor areas. In contrast, this did not occur when the signals were meaningful. Overall, the data suggest that the processes related to comprehension of symbolic gestures and communicative words do not involve primary motor area and probably use brain areas involved in semantics.
authors.affiliation: Dipartimento di Neuroscienze, Università di Parma, Parma, Italy.
authors.forename: Giovanna Cristina
authors.initials: GC
authors.lastname: Campione
authors.affiliation: Dipartimento di Neuroscienze, Università di Parma, Parma, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: De Stefani
authors.affiliation: Dipartimento di Neuroscienze, Università di Parma, Parma, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Innocenti
authors.affiliation: Dipartimento di Neuroscienze, Università di Parma, Parma, Italy.
authors.forename: Doriana
authors.initials: D
authors.lastname: De Marco
authors.affiliation: Dipartimento di Neuroscienze, Università di Parma, Parma, Italy.
authors.forename: Patricia M
authors.initials: PM
authors.lastname: Gough
authors.affiliation: Dipartimento di Scienze Mediche e Chirurgiche, Università Magna Graecia, Catanzaro, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Buccino
authors.affiliation: Dipartimento di Neuroscienze, Università di Parma, Parma, Italy; RTM (Rete Tecnologica Multidisciplinare), IIT (Istituto Italiano di Tecnologia) and Università di Parma, Italy. Electronic address: maurizio.gentilucci@unipr.it.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Gentilucci
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D032882:Comprehension / Q000502:physiology*; D004576:Electromyography; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D005868:Gestures; D006801:Humans; D008297:Male; D011930:Reaction Time; D012660:Semantics; D050781:Transcranial Magnetic Stimulation; D014705:Verbal Behavior; D014825:Vocabulary; D055815:Young Adult
keywords: Communicative word; Meaningful intransitive gesture; Meaningless gesture; Primary motor cortex (M1); Pseudo-word; Transcranial magnetic stimulation (TMS)