Degree of learning and linear forgetting

The aim of this study was to assess whether the degree of learning influences the observation of memory retention and forgetting that follows a linear pattern. According to our retention accuracy from fragmented traces (RAFT) model, one factor that should increase the likelihood of this is when there is greater learning of the material. Higher levels of learning can increase the number of trace components, making it more likely that reconstruction or partial retrieval can lead to an accurate response on a memory test. Here, we report three new experiments, as well as re-analyses of existing data from the literature, to show that increasing the level of learning in some ways can lead to increases in the likelihood of observing linear forgetting. For Experiment 1, people learned materials to different levels. This learning involved cued recall testing during memorisation. Linear forgetting was observed with increased learning. For Experiment 2, learning did not involve cued recall testing. Linear forgetting was not observed. Although our aim was not to test theories of retrieval practice, for Experiment 3, we showed that when people engage in this process, the pattern of retention and forgetting becomes more linear. Overall, these data are consistent with the RAFT theory and support mechanisms that it suggests can lead to the observation of linear forgetting.