Manipulating belief partially remedies the metamemory expectancy illusion in schema-based source monitoring

Metamemory illusions (i.e., false predictions of memory) are thought to arise from false a priori beliefs or from experiences made during study, such as processing fluency. The aim of the current research was to isolate the contribution of belief to metamemory by testing whether a correction of false beliefs can remedy a metamemory illusion. The authors focus on schema-based source monitoring, in which people show a metamemory expectancy illusion (e.g., Schaper et al., Journal of Experimental Psychology: Learning, Memory, and Cognition, 45(3), 470-496, 2019a). At study, people predict better source memory for items from expected sources (e.g., toothbrush in a bathroom), whereas actual source memory is better for items from unexpected sources (e.g., shampoo in a kitchen) or unaffected by expectations. In two source-monitoring experiments (N = 120/121), the authors tested whether the expectancy illusion could be remedied by correcting a priori belief. Participants studied items from expected and unexpected sources and made item-wise metamemory predictions about source memory. In both experiments, a manipulation to correct belief attenuated the expectancy illusion compared to a control group, but not to full remedy. Experiment 2 further revealed two distinct theoretical mechanisms underlying the partial persistence of the metamemory illusion: A partial inferential deficit, indicated by some participants failing to correct their belief, and a partial utilization deficit, indicated by participants failing to adequately use a corrected belief in metamemory judgments. The authors discuss competing influences of beliefs and experiences in metamemory judgment formation.