title: Brain activity modulation during the production of imperative and declarative pointing.
abstract: Pointing is a communicative gesture, commonly used for expressing two main intentions: imperative, to obtain a desired object/action from the other, or declarative, to share attention/interest about a referent with the other. Previous neuroimaging research on adults examined pointing almost exclusively as a reaching-like motor act rather than as a communicative gesture. Here, we used fMRI to record brain activity while 16 participants produced either imperative or declarative pointing gestures within a communicative context. A network of regions (the bilateral ventral premotor cortex, anterior midcingulate cortex, middle insula and the right preSMA) showed a preference for the production of declarative pointing as opposed to imperative pointing. The right preSMA also preferred declarative intention during pointing observation. Instead, independently from the intention, the right pMTG was more active during pointing observation than production. In the bilateral posterior parietal reach region we also observed a side (contra>ipsi) effect when the intention was imperative, regardless of the subject's role in the communication. Based on these results, we propose that pointing with declarative intention recruits a network of regions associated with will, motivation, emotional/affective expression and intersubjectivity, whereas pointing with imperative intention recruits regions associated with reaching. The proposal is consistent with the developmental hypothesis that declarative pointing reflects social cognitive abilities more than imperative pointing and establishes a stimulating link for future interdisciplinary research.
authors.affiliation: Department of Neuroscience, Imaging and Clinical Sciences, University G. d'Annunzio, via dei Vestini 33, 66013 Chieti Scalo, Italy; ITAB, Foundation G. d'Annunzio, via dei Vestini 33, 66013 Chieti Scalo, Italy. Electronic address: gcommitteri@unich.it.
authors.forename: Giorgia
authors.initials: G
authors.lastname: Committeri
authors.affiliation: Department of Neuroscience, Imaging and Clinical Sciences, University G. d'Annunzio, via dei Vestini 33, 66013 Chieti Scalo, Italy. Electronic address: cirillo.simona@virgilio.it.
authors.forename: Simona
authors.initials: S
authors.lastname: Cirillo
authors.affiliation: Department of Neuroscience, Imaging and Clinical Sciences, University G. d'Annunzio, via dei Vestini 33, 66013 Chieti Scalo, Italy; ITAB, Foundation G. d'Annunzio, via dei Vestini 33, 66013 Chieti Scalo, Italy; University of Ottawa, Institute of Mental Health Research, Ottawa, ON, Canada.. Electronic address: marcello.costantini@unich.it.
authors.forename: Marcello
authors.initials: M
authors.lastname: Costantini
authors.affiliation: Department of Psychology, Sapienza University, via dei Marsi 78, 00185 Rome, Italy; Laboratory of Neuropsychology, Santa Lucia Foundation, via Ardeatina 306, 00179 Rome, Italy. Electronic address: gaspare.galati@uniroma1.it.
authors.forename: Gaspare
authors.initials: G
authors.lastname: Galati
authors.affiliation: Department of Neuroscience, Imaging and Clinical Sciences, University G. d'Annunzio, via dei Vestini 33, 66013 Chieti Scalo, Italy; ITAB, Foundation G. d'Annunzio, via dei Vestini 33, 66013 Chieti Scalo, Italy. Electronic address: glromani@itab.unich.it.
authors.forename: Gian Luca
authors.initials: GL
authors.lastname: Romani
authors.affiliation: Department of Neuroscience, Imaging and Clinical Sciences, University G. d'Annunzio, via dei Vestini 33, 66013 Chieti Scalo, Italy. Electronic address: t.aureli@unich.it.
authors.forename: Tiziana
authors.initials: T
authors.lastname: Aureli
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D005385:Fingers; D005868:Gestures; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009043:Motor Activity; D055815:Young Adult
keywords: Declarative intention; Imperative intention; Pointing gesture; Reaching; Social abilities; fMRI