Abstract

In this study we investigated whether the cognitive system either processes information about implied motion in static pictures of hands or accesses the spatial information related to the destination of the intended action. To achieve our aims we applied the Sidedness paradigm (Ottoboni, Tessari, Cubelli, and Umiltà, 2005): the hands were presented in the centre of the screen with a coloured circle superimposed but, this time, they were rotated along radial-ulnar axe of 30° in order to give the sense of motion. Results showed a Sidedness effect for both the palm and the back views. Results showed a Sidedness effect for both the palm and the back views: a classical spatial effect of compatibility between the position of the hand of response (on the right vs. on the left side of the midline) and the identity of hand stimulus (right vs. left) for hand stimuli presented from the back view; but an opposite compatibility effect for hands in a palm view. More interestingly was the presence of a significant difference between the two stimulus postures: faster reaction times were found for hands presented from the palm view compared to those in the back view. Our interpretation resides on the context of social interaction, as the palm view hands might look like hands acting towards the observer. Results are discussed in light of the social feature coding literature.