To Help or Not to Help: Prosocial Motivation in Children at Risk for Autism Spectrum Disorder

Background: The social motivation hypothesis of autism spectrum disorder (ASD) posits that decreased social motivation in ASD may result in less attention to and thus fewer experiences with social sources of information, negatively influencing the development of social cognition and social-communicative abilities (Chevallier et al., 2012). As this reduction in social motivation is considered to be an etiological factor in ASD, we should be able to observe this difference early in life. However, the diagnosis of ASD can only be reliably made around the age of 2 to 3 years (Charman & Baird, 2008).
Younger siblings of children with an ASD have a 10 to 20 times higher risk of developing ASD themselves and are likely to share some behavioral characteristics with their older sibling (Szatmari et al., 2004). Therefore, the current study focused on intrinsically socially motivated behavior of these ‘high-risk (HR) siblings’, by administering helping tasks.

Objectives: The current study aims to extend our understanding of (pro)social motivation in HR siblings. Two research questions were formulated:
1. Is there a difference in helping behavior between high-risk and low-risk infants?
2. Is helping behavior associated with social-communicative abilities?

Methods: 24 HR siblings and 34 siblings of typically developing children (low-risk (LR) siblings), participating in a prospective study design, were tested in six helping tasks (Warneken & Tomasello, 2006, 2007) at 24 months of age. In the experimental condition (3 tasks) the researcher accidentally encountered a problem that she could not solve herself without the help of the child. In the control condition (the other 3 tasks, counterbalanced) a similar situation was created intentionally by the researcher and thus no help was needed. All sessions were videotaped and coded with regard to helping behavior and eye contact to the parent and researcher. Furthermore, the Autism Diagnostic Observation Schedule, Toddler module (ADOS-T; Lord et al., 2013) was administered.

Results: All participants helped more frequently in the experimental compared to the control condition, which suggests that the experimental manipulation was successful.
Second, a significant condition x group interaction showed that HR siblings helped less in the experimental condition than the LR infants. Their helping reactions were also slower. Furthermore, LR siblings made more eye contact with the researcher and parent in the control condition compared to the experimental condition, while there was no effect of condition on eye contact of HR siblings.
Finally, within the total sample, more frequent and faster helping behavior in the experimental condition was associated with lower ADOS-T social affect and total scores.

Conclusions: Given the less frequent and slower helping reactions of HR siblings, it is possible that also children at risk for ASD show lower levels of (pro)social motivation. Furthermore, we found evidence for less social referencing in the ambiguous control conditions in the HR group. LR infants checked more often with the parent and researcher during this strange social situation. Finally, frequency and speed of helping behavior was clearly related with social-communicative abilities in early development.