Abstract
INTRODUCTION: Previous work has revealed a lateral asymmetry in the production of emotional body language, consistent with related observations in faces: The left body half (LBH) moves with higher motion energy and amplitude, and is also perceived as more expressive (Roether et al. Curr.Biol., 2008). We tested whether this lateral asymmetry influences the looking behavior during the observation of emotional body stimuli by recording the associated eye movements. METHODS: Based on motion-capture data from emotional walks we created three sets of stimuli: 1) normal walks showing higher motion energy of the LBH; 2) stimuli mirrored about the horizontal symmetry axis, for which the movements of the right body half (RBH) were more expressive; and 3) perfectly symmetric chimeric walks created by presenting the movements of the LBH on both body sides. Participants performed an emotion classification task during which their eye movements were recorded. Fixation durations were determined separately for the LBH and RBH of the displayed avatars. The gaze bias (%fixation: left versus right) for each participant was calculated for different emotions, and walkers, followed by a cluster analysis of the obtained gaze biases. RESULTS: For all participants there was an almost significant trend to look more at the LBH: F(1,20)=3.81, p=.065. Between subjects, we found three different types of oculomotor response patterns that were associated with different gaze biases. The performance for the classification task between these groups did not significantly differ. CONCLUSIONS: Unexpectedly, we found three different gaze strategies that varied between participants. Those strategies were consistent over the three walker types (normal, mirrored, chimerical) and emotions. They reflect thus a general personal gaze preference rather than an influence of the saliency of emotion-specific features. In addition, there appears to be a tendency to look longer at the LBH than at the RBH.
Meeting abstract presented at VSS 2012