Balancing Cognitive Flexibility and Stability: The Role of Reward, Autism, and Transdiagnostic Traits

The balancing of cognitive flexibility versus stability is an important everyday skill that can be learned through reinforcement and may be impaired in autism or other transdiagnostic traits. In this preregistered study (n=412), we show that rewarding people more on task switch trials led them to show more voluntary switching behaviour, but also more task-rule interference. We further show that it is difficult to unlearn this shift along the flexibility-stability trade-off, even when the mapping between task switching and reward reversed. People with more autism traits or an autism diagnosis were equally fast at learning these contingencies but seemed to start from an overall smaller task-rule interference effect and larger switch costs – suggesting they show higher levels of cognitive stability at the cost of less flexibility. These patterns seemed unique to autism, as we failed to observe similar effects in four major transdiagnostic traits extracted from a principal component analysis based on 15 clinical questionnaires.