Beliefs about potential threats motivate avoidance behaviour. However, avoidance may also provide new learning experiences that can impact threat beliefs. Here, we use a novel task to explore this bidirectional relationship between aversive beliefs and avoidance. Specifically, we evaluate changes in outcome expectancies for locations on a grid-like sea-world before and after participants navigate a boat and avoid threatening locations. Using computational modelling we assess how participants generalise threat information to nearby locations and how these beliefs change as a result of avoidance. Initial piloting indicates that participants differ in the degree to which they generalise beliefs to nearby locations. Simulations further show how increased generalization influences avoidance and highlight the role of avoidance costs in shaping behavior. This work explores individual differences in belief-avoidance interplay and contributes to our understanding of how this interaction can lead to maladaptive patterns typical of anxiety.