Abstract
One recently proposed theory of autism spectrum disorder (ASD) hypothesizes that individuals with the disorder may have difficulty using prior experiences to predict future events [Hellendoorn et al., 2015; Northrup, 2016; Sinha et al., 2014]. To date, this theory has not been tested in infancy. The current study analyzed how young infants at heightened (HR; older sibling with ASD) vs. low risk (LR; no first degree relatives with ASD) for ASD responded to changing contingencies when interacting with two visually identical rattles-one that produced sounds during shaking (Sound), and one that did not (Silent). Infants were given the rattles in a Sound-Silent-Sound order at 6 and 10 months, and shaking behavior was coded. Results indicated that LR and HR infants (regardless of ASD diagnosis) did not differ from each other in shaking behavior at 6 months. However, by 10 months, LR infants demonstrated high initial shaking with all three rattles, indicating expectations for rattle affordances, while HR infants did not. Significantly, HR infants, and particularly those with an eventual ASD diagnosis, did not demonstrate an "extinction burst"-or high level of shaking-in the first 10 sec with the "silent" rattle, indicating that they may have difficulty generalizing learning from one interaction to the next. Further, individual differences in the strength of this "extinction burst" predicted cognitive development in toddlerhood among HR infants. Difficulty forming expectations for new interactions based on previous experiences could impact learning and behavior in a number of domains. Autism Res 2017. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. Autism Res 2017, 10: 1239-1248. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.