Wheeler and Roediger (1992) obtained evidence for both patterns within a single experiment, showing that, indeed, whether hypermnesia or forgetting occurs depends on the interval between tests. They presented participants with 60 pictures. For half the participants, the pictures were accompanied by their names, for the other half they were connected by a story. Then at
various delays, forced recall tests were administered. All groups received 3 consecutive tests one week after the learning
phase, but they had either 0, 1, or 3 consecutive tests immediately after the study stage.
The results showed that compared to an immediate test, a test administered after 1 week showed considerable forgetting (Bartlett’s result). However, tests administered close together in time produced the exact opposite, namely hypermnesia. In general, repeated tests are very beneficial for memory accuracy, whatever the inter-test delay. Whether or not the materials could
be linked by a story was irrelevant.