Theories of the generation effect and the impact of generation constraint: A meta-analytic review.

The generation effect is the memory benefit for self-generated compared with read or experimenter-provided information. In recent decades, numerous theories have been proposed to explain the memory mechanism(s) and boundary conditions of the generation effect. In this meta-analysis and theoretical review, we analyzed 126 articles (310 experiments, 1,653 estimates) to assess 7 prominent theories to determine which theories are supported by the existing literature. Because some theories focus on item memory (memory for the generated target) and others focus on context memory (memory for details associated with the generated target), we examined memory effects for both types of details (item, context) in this meta-analysis. Further, we assessed the influence of generation constraint (how constrained participants are to generate a certain response), which recent work has shown affects the magnitude of the generation effect. Overall, the results of this meta-analysis support some theoretical accounts, but not others, as explanatory mechanisms of the generation effect. Results further showed that generation constraint significantly moderates the magnitude of the generation effect, suggesting that this factor should be rigorously investigated in future work. Overall, this meta-analysis provides a review and examination of generation effect theories, and reveals important areas of future research.