Bruns Patrick, Shibata Kazuhisa, Watanabe Takeo
Department of Cognitive, Linguistic, and Psychological Sciences, Brown University, 190 Thayer Street, Providence, RI 02912, USA; Biological Psychology and Neuropsychology, University of Hamburg, Von-Melle-Park 11, 20146 Hamburg, Germany.
Center for Brain Science, RIKEN, 2-1 Hirosawa, Saitama 351-0106, Japan.
Curr Biol. 2025 Aug 27. doi: 10.1016/j.cub.2025.08.009.
Across various types of learning and memory, when a new training session follows a previous one after a certain temporal interval, the previously acquired learning can be disrupted-an effect known as retrograde interference (RI) or catastrophic forgetting. This disruption is thought to result from disrupting interactions between the learning of the first-trained task and the learning of the second-trained task while the former has not yet stabilized. Such destructive interactions have been considered characteristic not only of RI but also of related phenomena. However, we found that when the trained feature was subthreshold, the new learning session unexpectedly improved-rather than impaired-performance on the first-trained task, indicating a retrograde facilitation (RF) effect. We demonstrated this in visual perceptual learning (VPL) by conducting two successive training sessions on different coherent motion directions without any temporal gap. Consistent with previous research, when these directions were suprathreshold (10% coherent motion), the second session disrupted improvements from the first, reflecting RI. By contrast, when the trained directions were subthreshold (5% coherent motion), performance improvement on the first-trained direction was greater with a second session than without-indicating RF. Notably, RF was not observed when a 1-h interval separated the two subthreshold training sessions. This finding suggests that facilitative interactions occur only before the learning of the first-trained direction is stabilized. These results provide a new insight: a stimulus detection system related to conscious awareness transforms what would otherwise be facilitative interactions between successive VPL sessions into disruptive ones.
在各种类型的学习和记忆中，当在一定时间间隔后进行新的训练课程时，先前获得的学习可能会受到干扰——这种效应被称为逆行干扰（RI）或灾难性遗忘。这种干扰被认为是由于在第一个训练任务的学习尚未稳定时，破坏了第一个训练任务的学习与第二个训练任务的学习之间的相互作用而导致的。这种破坏性的相互作用不仅被认为是RI的特征，也是相关现象的特征。然而，我们发现，当训练特征低于阈值时，新的学习课程意外地提高了——而不是损害了——第一个训练任务的表现，这表明存在逆行促进（RF）效应。我们通过在不同的连贯运动方向上进行两个连续的训练课程且没有任何时间间隔，在视觉感知学习（VPL）中证明了这一点。与先前的研究一致，当这些方向高于阈值（连贯运动为10%）时，第二个课程破坏了第一个课程的进步，反映出RI。相比之下，当训练方向低于阈值（连贯运动为5%）时，第二个课程比没有第二个课程时，第一个训练方向上的表现提升更大——这表明存在RF。值得注意的是，当两个低于阈值的训练课程间隔1小时时，未观察到RF。这一发现表明，促进性相互作用仅在第一个训练方向的学习稳定之前发生。这些结果提供了一个新的见解：与意识觉知相关的刺激检测系统将原本连续的VPL课程之间的促进性相互作用转化为破坏性相互作用。
