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 spectrum disorders.

People appropriately adjust the distance between themselves and others during social interaction, and they may feel discomfort and move away when another person intrudes on their personal space. In the present study, we investigated personal space in children with persistent difficulties in the domain of social behavior, such as children with autism spectrum disorders (ASD), and in children with typical development (TD). The stop-distance paradigm was used to derive estimates of interpersonal distance, before and after a brief interaction with an unfamiliar adult confederate. The results showed that ASD children felt comfortable at a greater distance compared to TD children. Moreover, personal space shrunk after interaction with the confederate in TD children, but it failed to do so in ASD children. These findings reveal that autism deeply affects the regulation of personal space, influencing both its size and flexibility.

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).

Scared by you: modulation of bodily-self by emotional body-postures in autism.

OBJECTIVE: Bodily self-recognition is one aspect of our ability to distinguish between self and others and is central to effective socialization. Here we explored the influence of emotional body postures on bodily self-processing in typically developing (TD) as well as in high-functioning ASD children. METHOD: Subjects' bodies were photographed while expressing endogenously- (self-generated, Experiment 1) or exogenously-driven body emotions (imitated upon request, Experiment 2). Postures conveying positive (happiness), negative (fearful) and neutral valences were used. These pictures served as stimuli in a visual matching-to-sample task with self and others' body-images. RESULTS: A similar self-versus-others advantage was found in TD and in ASD children, since participants were faster with stimuli representing their own than others' body. This "self-advantage" was modulated by self-expressed emotional body postures being present with pictures of happy and neutral, but not fearful body images. This modulation was stronger when emotional postures were endogenously rather than exogenously driven. Moreover, faster responses were observed for others' fearful rather than happy or neutral body images in both groups. CONCLUSIONS: The bodily self-advantage is a low-level function present in typically developing (TD) and in high-functioning ASD children. Body postures, especially when they are endogenously generated, modulate the self and others' body processing. The advantage for processing others' fearful, comparing to others' happy and neutral, body postures may have played a crucial evolutionary role for species survival.

Intention understanding in autism.

When we observe a motor act (e.g. grasping a cup) done by another individual, we extract, according to how the motor act is performed and its context, two types of information: the goal (grasping) and the intention underlying it (e.g. grasping for drinking). Here we examined whether children with autistic spectrum disorder (ASD) are able to understand these two aspects of motor acts. Two experiments were carried out. In the first, one group of high-functioning children with ASD and one of typically developing (TD) children were presented with pictures showing hand-object interactions and asked what the individual was doing and why. In half of the "why" trials the observed grip was congruent with the function of the object ("why-use" trials), in the other half it corresponded to the grip typically used to move that object ("why-place" trials). The results showed that children with ASD have no difficulties in reporting the goals of individual motor acts. In contrast they made several errors in the why task with all errors occurring in the "why-place" trials. In the second experiment the same two groups of children saw pictures showing a hand-grip congruent with the object use, but within a context suggesting either the use of the object or its placement into a container. Here children with ASD performed as TD children, correctly indicating the agent's intention. In conclusion, our data show that understanding others' intentions can occur in two ways: by relying on motor information derived from the hand-object interaction, and by using functional information derived from the object's standard use. Children with ASD have no deficit in the second type of understanding, while they have difficulties in understanding others' intentions when they have to rely exclusively on motor cues.