To assess whether taking into account interaction synchrony would help to better differentiate autism (AD) from intellectual disability (ID) and typical development (TD) in family home movies of infants aged less than 18 months, we used computational methods. First, we analyzed interactive sequences extracted from home movies of children with AD (N = 15), ID (N = 12), or TD (N = 15) through the Infant and Caregiver Behavior Scale (ICBS). Second, discrete behaviors between baby (BB) and Care Giver (CG) co-occurring in less than 3 seconds were selected as single interactive patterns (or dyadic events) for analysis of the two directions of interaction (CG→BB and BB→CG) by group and semester. To do so, we used a Markov assumption, a Generalized Linear Mixed Model, and non negative matrix factorization. Compared to TD children, BBs with AD exhibit a growing deviant development of interactive patterns whereas those with ID rather show an initial delay of development. Parents of AD and ID do not differ very much from parents of TD when responding to their child. However, when initiating interaction, parents use more touching and regulation up behaviors as early as the first semester. When studying interactive patterns, deviant autistic behaviors appear before 18 months. Parents seem to feel the lack of interactive initiative and responsiveness of their babies and try to increasingly supply soliciting behaviors. Thus we stress that credence should be given to parents' intuition as they recognize, long before diagnosis, the pathological process through the interactive pattern with their child.

Background Whether development of autism impacts the interactive process between an infant and his/her parents remains an unexplored issue. Methodology and Principal Findings Using computational analysis taking into account synchronic behaviors and emotional prosody (parentese), we assessed the course of infants' responses to parents' type of speech in home movies from typically developing (TD) infants and infants who will subsequently develop autism aged less than 18 months. Our findings indicate: that parentese was significantly associated with infant responses to parental vocalizations involving orientation towards other people and with infant receptive behaviours; that parents of infants developing autism displayed more intense solicitations that were rich in parentese; that fathers of infants developing autism spoke to their infants more than fathers of TD infants; and that fathers' vocalizations were significantly associated with intersubjective responses and active behaviours in infants who subsequently developed autism. Conclusion The parents of infants who will later develop autism change their interactive pattern of behaviour by both increasing parentese and father's involvement in interacting with infants; both are significantly associated with infant's social responses. We stress the possible therapeutic implications of these findings and its implication for Dean Falk's theory regarding pre-linguistic evolution in early hominins.

Conduct Disorder (CD) is a psychiatric diagnosis characterized by a repetitive and persistent pattern of behaviour in which the basic rights of others and major age-appropriate social norms or rules are violated. Callous Unemotional (CU) traits are a meaningful specifier in subtyping CD for more severe antisocial and aggressive behaviours in adult psychopathology; they represent the affective dimension of adult psychopathy, but they can be also detected in childhood and adolescence. The CU traits include lack of empathy, sense of guilt and shallow emotion, and their characterization in youth can improve our diagnostic, prognostic and therapeutic abilities. A strong genetic liability, in interaction with parenting and relevant environmental factors, can lead to elevated levels of CU traits in children. We pointed out that CU traits can be detected in early childhood, may remain stable along the adolescence, but a decrease following intensive and specialized treatment is possible. We here provide a narrative review of the available evidences on CU traits in three main domains: aetiology (encompassing genetic liability and environmental risk factors), presentation (early signs and longitudinal trajectories) and treatments.