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The study of visual peculiarities in autistic spectrum disorder (ASD) subjects gives rise to one principal question: Do the peculiarities manifest themselves only in response to socio-emotional stimuli such as facial expressions, or are they a general marker of autistic visual processing? To answer this question, a systematic comparison of different kinds of stimuli is required. Until now only static stimuli have been systematically compared. When dynamic stimuli were used, the comparison did not take into account important parameters distinguishing moving faces from moving objects. We developed a morphing design allowing us to control the speed of presentation and complexity of moving faces, robots, and objects (http://www.lutin-userlab.fr/FOT/). Using this design, we have conducted a series of experiments combining morphing and eye tracking techniques. Twelve non-verbal adolescents were compared with two typical groups: a developmental age- matched and a chronological age- matched group. Results show an asymmetry in the perceptual processing, depending upon the stimulus: it remains intact for objects but significantly lower performing for emotional stimuli. The comparison of visual fixations on emotional robotic expressions as compared to human expressions suggests a processing of movement rather than a processing of emotional signal.