We examined selective directed forgetting in motor memory using a new variant of a three-list approach, to distinguish between accounts of directed forgetting. Participants consecutively studied three lists (L1, L2, and L3) of four sequential four-finger movements each. After studying L2, participants in the forget group were instructed to selectively forget the just studied four items of L2 but to retain the previously studied four items of L1, whereas the remember group did not receive any forget instruction for L2 but was encouraged to retain the items of both lists. In addition, we switched (switch groups) or repeated the items-enacting hand (no-switch groups) between L2 and L3 for a manipulation of post-forget-cue material competition for L2. A final memory test assessed recall performance for all three lists. Selective directed forgetting (lower L2 recall in the forget group as compared to the remember group) only occurred if the same hand was used for L2 and L3 (high interference between L2 and L3 encoding) whereas no selective directed forgetting occurred if the hand switched between L2 and L3 (low interference between L2 and L3 encoding). These results suggest that an inhibitory mechanism caused (selective) directed-forgetting costs that was triggered when items studied after the forget instruction had the potential to interfere with already stored items (i.e. were to be enacted by the same hand). When subsequently studied items pertained to the other hand no directed-forgetting costs occurred.

我们使用三列表方法的新变体检查了运动记忆中的选择性定向遗忘，以区分定向遗忘的帐户。参与者连续研究了四个连续四指运动的三个列表（L1、L2 和 L3）。在学习完 L2 后，遗忘组被要求选择性地忘记刚刚学习的 L2 的 4 个项目，但保留先前学习的 L1 的 4 个项目，而记忆组没有接受任何 L2 的遗忘指令，但被鼓励保留两个列表的项目。此外，我们切换（切换组）或重复项目生成手（无切换组）) 在 L2 和 L3 之间用于操纵 L2 的后遗忘提示材料竞争。最后的记忆测试评估了所有三个列表的回忆性能。选择性定向遗忘（与记忆组相比，遗忘组中的 L2 回忆较低) 仅在同一只手用于 L2 和 L3（L2 和 L3 编码之间的高干扰）时发生，而如果手在 L2 和 L3 之间切换（L2 和 L3 编码之间的低干扰），则不会发生选择性定向遗忘。这些结果表明，当在遗忘指令后研究的项目有可能干扰已经存储的项目（即由同一只手制定）时，会引发（选择性）定向遗忘成本的抑制机制。当随后研究与另一方面有关的项目时，没有发生定向遗忘成本。