Abstract: Retrieval-induced forgetting (hereafter, RIF) is defined as the repeated retrieval practice of some materials induces the forgetting of the other materials. Currently, two main theories have been put forward to explain the phenomenon of RIF. The inhibition theory assumes that this forgetting results from the inhibitory processes that function to resolve interference during retrieval. The interference theory proposes that this forgetting is the consequence of interference functioning during the last test phase. Although a bulk of studies was carried out to distinguish these two influential theories, there were still some controversies to be resolved. The present study aimed to examine how the item strength and test order impacted on the RIF. On the basis of this, the debate related with the two theories as mentioned above was discussed in depth. In the present study, sixty-four undergraduates were tested separately. All the forty-eight category-exemplar word pairs were presented once at a time for all the participants. Then, they were instructed to recall half of the exemplars from the half categories which had been studied in the previous phase according to the retrieval cues. By convention, three types of items were produced by the retrieval practice: the practiced exemplars were referred as Rp+ item; the unpracticed exemplars from practiced categories were defined as Rp-item; and the exemplars from unpracticed categories were referred as Nrp item. After an appropriate 2-minute distracter task, participants were shown a category-plus-initial-letter cue and were requested to recall all the exemplars which had been studied before. The results showed that, the retrieval accuracy for the Rp+ items was significantly higher than that for the Nrp items, and this effect was not modulated by the item strength and the test order. Moreover, the RIF was merely observed on the strong items, but not for the weak items. Even when the output effect occurred from the test order were effectively controlled, the strong items still triggered the RIF apparently. Overall, the present results indicated that the effect of RIF was affected by the item strength and the test order. Based on this，we argued that, the inhibitory theory of RIF was supported to some extent.

Key words: retrieval-induced forgetting, item strength, test order, inhibitory theory, strength-dependence competition theory

摘要： 提取诱发遗忘是指对先前学过的部分材料进行提取练习会使与练习材料相关的其它材料发生遗忘。目前该现象存在抑制与非抑制理论之争。本研究以64名大学生为被试，通过考察项目强度和测试顺序对提取诱发遗忘的影响，对上述争论进行了探讨。结果表明：（1）只有高强度项目才会引发提取诱发遗忘；（2）当控制由测试顺序所产生的输出干扰效应后，高强度项目仍然会引发提取诱发遗忘。本研究结果支持了提取诱发遗忘的抑制理论。

关键词: 提取诱发遗忘, 项目强度, 测试顺序, 抑制理论, 强度依赖竞争理论