When social and action spaces diverge: A study in children with typical development and autism.

The space around the body has been defined as action space (peripersonal space) and a social space (interpersonal space). Within the current debate about the characteristics of these spaces, here we investigated the functional properties and plasticity of action and social space in developmental age. To these aims, children with typical development and autism spectrum disorders were submitted to Reaching- and Comfort-distance tasks, to assess peripersonal and interpersonal space, respectively. Participants approached a person (confederate) or an object and stopped when they thought they could reach the stimulus (Reaching-distance task), or they felt comfortable with stimulus' proximity (Comfort-distance task). Both tasks were performed before and after a cooperative tool-use training, in which participant and confederate actively cooperated to reach tokens by using either a long (Experiment 1) or a short (Experiment 2) tool. Results showed that in both groups, peripersonal space extended following long-tool-use but not short-tool-use training. Conversely, in typical development, but not in autism spectrum disorders children, interpersonal space toward confederate reduced following the cooperative tool-use training. These findings reveal that action and social spaces are functionally dissociable both in typical and atypical development, and that action but not social space regulation is intact in children with autism.

Personal space regulation in childhood autism: Effects of social interaction and person's perspective.

Studies in children with Typical Development (TD) and with Autism Spectrum Disorder (ASD) revealed that autism affects the personal space regulation, influencing both its size (permeability) and its changes depending on social interaction (flexibility). Here, we investigate how the nature of social interaction (Cooperative vs. Uncooperative) and the person perspective influence permeability and flexibility of interpersonal distance. Moreover, we tested whether the deficit observed in ASD children, reflects the social impairment (SI) in daily interactions. The stop-distance paradigm was used to measure the preferred distance between the participant and an unfamiliar adult (first-person perspective, Experiment 1), and between two other people (third-person perspective, Experiment 2). Interpersonal distance was measured before and after the interaction with a confederate. The Wing Subgroups Questionnaire was used to evaluate SI in everyday activities, and each ASD participant was accordingly assigned either to the lower (children with low social impairment [low-SI ASD]), or to the higher SI group (children with high social impairment [high-SI ASD]). We observed larger interpersonal distance (permeability) in both ASD groups compared to TD children. Moreover, depending on the nature of social interaction, a modulation of interpersonal distance (flexibility) was observed in TD children, both from the first- and third-person perspective. Similar findings were found in low-SI but not in high-SI ASD children, in Experiment 1. Conversely, in Experiment 2, no change was observed in both ASD groups. These findings reveal that SI severity and a person's perspective may account for the deficit observed in autism when flexibility, but not permeability, of personal space is considered. Autism Res 2017, 10: 144-154. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

Motor representation of actions in children with autism.

BACKGROUND: Children with Autistic Spectrum Disorders (ASD) are frequently hampered by motor impairment, with difficulties ranging from imitation of actions to recognition of motor intentions. Such a widespread inefficiency of the motor system is likely to interfere on the ontogeny of both motor planning and understanding of the goals of actions, thus delivering its ultimate effects on the emergence of social cognition. METHODOLOGY/PRINCIPAL FINDINGS: We investigate the organization of action representation in 15 high functioning ASD (mean age: 8.11) and in two control samples of typically developing (TD) children: the first one, from a primary school, was matched for chronological age (CA), the second one, from a kindergarten, comprised children of much younger age (CY). We used nine newly designed behavioural motor tasks, aiming at exploring three domains of motor cognition: 1) imitation of actions, 2) production of pantomimes, and 3) comprehension of pantomimes. The findings reveal that ASD children fare significantly worse than the two control samples in each of the inspected components of the motor representation of actions, be it the imitation of gestures, the self-planning of pantomimes, or the (verbal) comprehension of observed pantomimes. In the latter task, owing to its cognitive complexity, ASD children come close to the younger TD children's level of performance; yet they fare significantly worse with respect to their age-mate controls. Overall, ASD children reveal a profound damage to the mechanisms that control both production and pre-cognitive "comprehension" of the motor representation of actions. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that many of the social cognitive impairments manifested by ASD individuals are likely rooted in their incapacity to assemble and directly grasp the intrinsic goal-related organization of motor behaviour. Such impairment of motor cognition might be partly due to an early damage of the Mirror Neuron Mechanism (MNM).