When Should We Expect Indirect Effects in Human Contingency Learning?

How do we learn causal relations between events from experience? Many have argued for an associative account inspired by animal conditioning models, but there is a growing literature arguing that indirect effects in contingency learning depend on explicit cognitive processes. Our experiments explore the basis of two such effects: blocking and screening off. In Experiment 1, we gave participants an untimed explicit prediction task to replicate standard findings in the contingency learning literature in a novel domain. We obtained robust indirect effects when participants had a causal framework to constrain their reasoning. In Experiment 2, we reduced the time available for explicit recollection by reconstructing the task as a fast-paced RT task. Participants continued to show robust learning of direct relationships, as measured by response times, but there were no indirect effects. Experiment 3 followed up on whether participants in our RT task would produce indirect effects through explicit processes when given an opportunity to make a more deliberative prediction at test.