This project uses experimental data from 880 participants to investigate four hypotheses: (1) whether reward-based decision-making improves through experience; (2) whether psychological distancing improves reinforcement learning; (3) whether distancing moderates emotional responses to rewarding and non-rewarding outcomes; and (4) whether psychological symptoms can be explained by three underlying transdiagnostic dimensions. The analyses apply mixed-effects modelling and exploratory and confirmatory factor analysis in R to test four hypotheses.