Automatic measure of imitation during social interaction: A behavioral and hyperscanning-EEG benchmark

Emilie Delaherche, Guillaume Dumas, Jacqueline Nadel, Mohamed Chetouani
<span title="">2015</span> <i title="Elsevier BV"> <a target="_blank" rel="noopener" href="" style="color: black;">Pattern Recognition Letters</a> </i> &nbsp;
Social neuroscience shows a growing interest for the study of social interaction. Investigating its neural underpinnings has been greatly facilitated through the development of hyperscanning, a neuroimaging technique allowing to record simultaneously the brain activity of multiple humans engaged in a social exchange. However, the analysis of spontaneous social interaction requires the indexing of the ongoing behavior. Since spontaneous exchanges are intrinsically unconstrained, only a manual
more &raquo; ... exing by frame-by-frame analysis has been used so far. Here we present an automatic measure of imitation during spontaneous social interaction. Participants gestures are characterized with Bag of Words and 1-Class SVM models. Then a measure of imitation is derived from the likelihood ratio between these models. We apply this method to hyperscanning EEG recordings of spontaneous imitation of bimanual hand movements. The comparison with manual indexing validates the method at both behavioral and neural levels, demonstrating its ability to discriminate significantly the periods of imitation and non-imitation during social interaction. (E. Delaherche). 1 These authors contributed equally to this paper. by hand, a long process of frame-by-frame video analysis. Here we propose an automatic indexing of imitative behavior during spontaneous interaction. We compare this technique with the traditional frame-by-frame approach and quantify how it impacts subsequent neurodynamical analyses at both intra-and inter-individual levels with hyperscanning-EEG. Imitative behavior in spontaneous interaction During social interaction, people spontaneously imitate their social interaction partners, including mimicry of his gestures [9], his facial expressions [10, 11] , his mannerism [9], and his posture [12, 13] . Mimicry facilitates affiliation [14] and good understanding between individuals [12, 15] . Many terms are associated with mimicry in the literature: behavior matching [16] , mirroring, congruence and the chameleon effect [9] . This nonconscious form of imitation is notably different than conscious imitation which is commonly considered as a foundation for learning, socialization and communication [17, 18] . In spontaneous exchanges, it becomes for instance a mean of communication [19] . While mimicry is still present, the behavior becomes more complex, giving rise to alternation between roles of imitator and driver. In neuroscience, this lack of control forced the study of imitation to be limited at the intra-individual level and induced http://dx.
<span class="external-identifiers"> <a target="_blank" rel="external noopener noreferrer" href="">doi:10.1016/j.patrec.2014.09.002</a> <a target="_blank" rel="external noopener" href="">fatcat:muniepodtrhhth6lvluk2ivfty</a> </span>
<a target="_blank" rel="noopener" href="" title="fulltext PDF download" data-goatcounter-click="serp-fulltext" data-goatcounter-title="serp-fulltext"> <button class="ui simple right pointing dropdown compact black labeled icon button serp-button"> <i class="icon ia-icon"></i> Web Archive [PDF] <div class="menu fulltext-thumbnail"> <img src="" alt="fulltext thumbnail" loading="lazy"> </div> </button> </a> <a target="_blank" rel="external noopener noreferrer" href=""> <button class="ui left aligned compact blue labeled icon button serp-button"> <i class="external alternate icon"></i> </button> </a>