Abstract

The pretesting effect refers to the enhancement of learning due to unsuccessful retrieval upon being asked a question that is not easily answered, However, the results of research on the effect of overt retrieval on learning, have not been consistent. Therefore, the present study sought to clarify such confusion. We examined whether memory enhancement is affected by the number of wrong answers generated by the examinees and by the duration of retrieval. Four experiments were carried out with college students as participants. In Experiments 1 and 2, we manipulated the number of unsuccessful retrievals to either 1 or 3, and observed that there was no difference in performance. In Experiments 3 and 4, participants were asked to think of possible answers without overt responses. The results showed that the performance was better for those who were asked to think of more answers. The present study also examined whether pretesting effect is found even after a week's duration. After a week, pretesting effect was observed in case of the covert retrieval group; however it did not last for the overt retrieval group. These results support the search set theory by Grimaladi and Karpicke (2012) which states that active exploration of related material promotes learning. The present study also suggests that overt retrieval brings about retrieval competition and interferes with the retrieval of correct responses, and thus disrupts learning.