Absence of Adolescent-Specific Sensitivity to Motivating Cues in Autism

Background: Extensive research has shown that typically developing adolescents show increased attention towards motivating cues relative to children and adults, that is accompanied by adolescent-specific changes in reward sensitive frontostriatal circuitry. However, it is unknown whether motivating cues elicit a similar bias during adolescence in autism.

Objectives: The aim of this study was to investigate adolescent-specific changes in sensitivity to motivating cues (social and non-social stimuli) in individuals with and without autism. We expected typically developing participants would show a bias towards positive social cues during adolescence and that individuals with autism would not show such sensitivity.

Methods: 105 typically developing participants and 71 participants with autism, aged 10-30 years, performed a novel go-nogo task on an iPad. For the social conditions, participants were presented with happy and calm faces. For the interest conditions, participants chose their favorite (interest) and least favorite hobby/activity (non-interest) from 23 options. There were 4 different runs of go-nogo pairs (happy vs. calm, calm vs. happy, interests vs. non-interests, non-interests vs. interests). Participants were instructed to press to the target cue (go) when it appeared on screen and not press to the distractor cue (nogo). False alarms for happy minus calm faces and interests minus non-interests were calculated for each participant. Linear and quadratic age models were fitted to test for developmental differences in the difference scores between diagnostic groups across age.

Results: We compared false alarms for happy faces minus calm faces and, as shown in Figure 1, there were no adolescent-specific changes in autism (linear & quadratic models not significant). In contrast, typically developing teens and young adults had greater false alarms for happy minus calm faces with an interaction between quadratic age and diagnostic group (p = 0.02). We found no differences across age in autism or typically developing individuals for false alarms to interests minus non-interests.

Conclusions: The findings suggest that adolescents with autism did not show increased sensitivity to either social or non-social cues, compared to typically developing teens who demonstrated increased sensitivity to positive social cues, in line with previous work. Greater sensitivity towards motivating cues in typical development is thought to underlie the observed increases in risk taking behavior and growth of independence skills associated with adolescence and young adulthood. Therefore, the absence of increased motivation during adolescence in autism may explain some of the challenges with independent living skills associated with early adulthood. Future work will explore the neural mechanisms towards motivating cues to better understand adolescent-specific difficulties in autism.