Coding valence in touchscreen interactions: hand dominance and lateral movement influence valence appraisals of emotional pictures.

The Body-Specificity Hypothesis postulates that the space surrounding the dominant hand is perceived as positive due to the motor fluency of this hand, whereas the space surrounding the non-dominant hand is perceived as negative. Experimental studies based on this theoretical framework also revealed associations between affective valence and hand dominance (i.e., dominant hand-positive; non-dominant hand-negative), or lateral movements of the hands (i.e., right hand toward the right space-positive; left hand toward the left space-positive). Interestingly, these associations have not been examined with regard to how lateral actions of the hands may influence affective experiences as, for example, in valence appraisals of affective objects that have been manipulated. The study presented here has considered this question in light of the emerging interest of embodied cognition approaches to interactive technologies, particularly in affective experiences with touchscreen interfaces. Accordingly, right-handed participants evaluated the valence of positive and negative emotional pictures after interacting with them either with the dominant right or with the non-dominant left hand. Specifically, they moved the pictures either from left to right or from right to left sides of a touchscreen monitor. The results indicated that a valence matching between the hand used for the interactions, the picture's valence category, and the movement's starting side reinforced the valence appraisals of the pictures (i.e., positive/negative pictures were more positively/negatively evaluated). The findings are discussed against the background of the Theory of Event Coding, which accounts for both the affective properties of the stimuli and the affective connotation of the related action.