The feature boost in false memory: the roles of monitoring and critical item identifiability

The feature boost refers to increased false memories for word lists that are both associatively and categorically (C + A) related to a non-presented critical item (CI) relative to lists that are only associatively (NC-A) related [Coane, J. H., McBride, D. M., Termonen, M.-L., & Cutting, J. C. (2016). Categorical and associative relations increase false memory relative to purely associative relations. Memory & Cognition, 44(1), 37-49. doi:10.3758/s13421-015-0543-1]. We explored the replicability of the feature boost and its dependance on monitoring processes by explicitly warning participants about the nature of the lists or by asking participants to guess the CI (implicit warning). Overall, the feature boost was replicated. Guessing performance was higher for C + A lists than for NC-A lists. Explicit warnings were equally effective for both list types in reducing false memory relative to recall and to a no-recall math condition. When the CI was not guessed or recalled, the feature boost emerged. However, when the CI was guessed or previously recalled, false alarms did not differ as a function of list type. The feature boost seems to be driven in part by differences in the identifiability of the CI, such that CIs related to C + A lists are harder to identify and thus reject. These results suggest that differences in monitoring processes that are sensitive to CI identifiability contribute to the effect.