Agency and reward across development and in autism: A free-choice paradigm

Abstract

Our ability to perform voluntary actions and make choices is shaped by the motivation from control over the resulting effects (agency) and from positive outcomes (reward). The underlying action-outcome binding mechanisms rely on sensorimotor abilities that specialise through child development and undergo different trajectories in autism. The study aimed at disentangling the role of agency and reward in driving action selection of autistic and non-autistic children and adults, who were asked to freely select one of three candies and feed the animals appearing on a tablet. The candies were associated with different probabilities of delivering a neutral vs no effect (agency task), or a positive vs neutral effect (reward task). Choices and reaction times (RT) were measured to understand whether participants preferred and were faster at selecting options with higher probability of producing a neutral vs. no effect (agency) or a positive vs. neutral effect (reward). Participants' choices and RT were not affected by agency, whereas a more frequent selection of the option with higher probability of a positive vs. neutral effect emerged across groups, thus suggesting a reward effect. Autistic participants selected less frequently the option with chance level of receiving a neutral or no effect, which could be interpreted as a sign of reduced tolerance of uncertainty. Across tasks, conditions and age groups, autistic participants presented shorter RT, which is a marker of reduced action planning and control. Future research should deepen how tolerance of uncertainty, action planning and control impact the way autistic individuals make choices in everyday life situations, potentially contributing to restricted and repetitive behaviours.

Fig 1. Agency and reward tasks.

Fig 2. Group effect predicted by m1.

Relative choice of the response with medium—vs. low—probability of delivering a neutral vs. no effect, with whiskers representing 95% confidence intervals.

Fig 3. Group effect on RT (agency task), as predicted by m2.

Estimated marginal means with whiskers representing 95% confidence intervals.

Fig 4. Button probability effect predicted by m0.

Relative choice of the response with low vs high and low vs medium probability of delivering a positive vs. neutral effect, with whiskers representing 95% confidence intervals.

Fig 5. Group difference in RT (reward task), as predicted by model m2.

Estimated marginal means with whiskers representing 95% confidence intervals.

Fig 6. Correlations with autistic traits.

n = 42.