Reduced delay-based executive function in autistic toddlers and preschoolers

"Hot" or reward-based executive function describes the regulatory skills needed to suppress or delay actions in emotionally salient contexts. These delay-based executive function skills impact social development, mental health, and academic achievement. Accumulating evidence indicates that autistic children (3 years or older) show reduced delay-based executive function relative to neurotypical counterparts. The primary aim of this study was to determine whether these findings extend to younger children (younger than 3 years). Our secondary aim was to determine whether the strategies employed during delay-based executive function tasks differed between autistic and neurotypical toddlers, to understand <i>why</i> autistic children often experience difficulty in this domain. A behavioral battery was administered to measure delay-based executive function in autistic and neurotypical children, aged 2 and 4 years. Consistent with evidence in older children, delay-based executive function was reduced in autistic toddlers. Autistic 2-year-olds waited less during tasks that utilized food rewards, whereas autistic 4-year-olds waited less during tasks using both food- and non-food-based incentives. Autistic children also used significantly less adaptive strategies during tasks. These results are the first to indicate diagnostic differences in delay-based executive function among children as young as 2 years and may inform interventions that target these skills to improve related developmental outcomes.Lay Abstract"Hot" executive function involves the ability to control actions when emotions are involved. For example, a situation when an individual must resist a temptation requires hot executive function. These skills are important for social growth, mental health, and doing well in school. Research shows that autistic children over 3 years of age are less likely to use these skills compared to other children. This study examined whether autistic children under 3 years of age show similar difficulties. We also examined whether autistic children use different strategies than neurotypical children. To find out, we asked both autistic and neurotypical children, ages 2 and 4 years, to complete tasks that required them to delay their responses. The study found that, like older autistic children, younger autistic children also delayed their responses less than neurotypical children. Autistic 2-year-olds waited less for rewards, like food, compared to their neurotypical peers. Similarly, autistic 4-year-olds waited less for both food and other types of rewards, compared to their neurotypical peers. Relative to their neurotypical peers, autistic children also used fewer effective strategies during these tasks. These findings suggest that even very young autistic children have differences in impulse control, which might help in creating better support and interventions for them.