¹²In particular, such mental imagery may serve to increase the perceived probability of adverse events based on what is called the availability heuristic (Tversky and Kahneman, 1974). That is, humans tend to estimate the probability of events based on how easily they can recall (or imagine) those events. If you willfully imagine an event happening in the future, that will make the event more accessible in terms of memory retrieval, and thus you may start considering its probability of happening is higher. When things going wrong are perceived to have a higher probability, expected reward is necessarily reduced. Thus, imagining adverse events may be a particularly powerful way of influencing unconscious decision-making processes.