The Role of Feedback for the Testing Effect
Final Report Abstract
The testing effect refers to the finding that retrieval practice in comparison to restudy of previously encoded material typically improves recall performance on a later test. This beneficial effect of retrieval practice typically arises in the absence of any re-exposure to the study material via feedback. A very recent single study, however, has demonstrated that the testing effect can be reversed when such feedback is provided during the later test. This finding suggests that the benefit of retrieval practice may not easily generalize to situations in which feedback is provided. The goal of the present research project is to specify the conditions under which providing feedback promotes recall of previously practiced material, and under which conditions it does not. In particular, on the basis of Kornell, Bjork, and Garcia’s (2011) bifurcation model of the testing effect, the hypothesis was tested that types of practice which initially result in a relatively weak recall performance should benefit more from feedback than types of practice that initially generate a superior recall performance. The present research project intends to examine the hypothesis in 3 experiments, in each of which one type of practice is employed that initially produces low recall performance, as well as one type of practice that initially produces high recall performance. Specifically, recall performance was modulated by either manipulating difficulty of retrieval practice (Experiment 1), the length of the retention interval between retrieval practice and the later test (Experiment 2), and by either inducing retroactive interference, or not (Experiment 3). Replicating prior research, the results showed that in a first final test, recall of the study items was better (1) following difficult than easy practice, (2) after a short than a longer retention interval, (3) and in the absence than presence of retroactive interference. Critically, however, immediate feedback at test either reversed (Experiment 1), reduced (Experiment 2), or eliminated (Experiment 3) these patterns, thus confirming the hypothesis that feedback during test is more beneficial for types of practice that initially lead to inferior recall performance. These findings provide a new perspective on the testing effect and demonstrate the critical role of feedback for the effects of different forms of retrieval practice.
