CICPSI, Faculdade de Psicologia, Universidade de Lisboa, Lisboa, Portugal.
GIGA-CRC In-Vivo Imaging, University of Liège, Liège, Belgium.
Mem Cognit. 2024 Oct;52(7):1567-1578. doi: 10.3758/s13421-024-01563-2. Epub 2024 May 6.
Although long-term visual memory (LTVM) has a remarkable capacity, the fidelity of its episodic representations can be influenced by at least two intertwined interference mechanisms during the encoding of objects belonging to the same category: the capacity to hold similar episodic traces (e.g., different birds) and the conceptual similarity of the encoded traces (e.g., a sparrow shares more features with a robin than with a penguin). The precision of episodic traces can be tested by having participants discriminate lures (unseen objects) from targets (seen objects) representing different exemplars of the same concept (e.g., two visually similar penguins), which generates interference at retrieval that can be solved if efficient pattern separation happened during encoding. The present study examines the impact of within-category encoding interference on the fidelity of mnemonic object representations, by manipulating an index of cumulative conceptual interference that represents the concurrent impact of capacity and similarity. The precision of mnemonic discrimination was further assessed by measuring the impact of visual similarity between targets and lures in a recognition task. Our results show a significant decrement in the correct identification of targets for increasing interference. Correct rejections of lures were also negatively impacted by cumulative interference as well as by the visual similarity with the target. Most interestingly though, mnemonic discrimination for targets presented with a visually similar lure was more difficult when objects were encoded under lower, not higher, interference. These findings counter a simply additive impact of interference on the fidelity of object representations providing a finer-grained, multi-factorial, understanding of interference in LTVM.
尽管长时视觉记忆（LTVM）具有非凡的容量，但在对属于同一类别的物体进行编码时，至少有两种相互交织的干扰机制会影响其情景记忆的保真度：持有类似情景痕迹的能力（例如，不同的鸟类）和编码痕迹的概念相似性（例如，麻雀与知更鸟的特征比与企鹅的特征更相似）。可以通过让参与者辨别诱饵（未见过的物体）和目标（见过的物体）来测试情景痕迹的准确性，这些目标代表同一概念的不同范例（例如，两个视觉上相似的企鹅），这会在检索时产生干扰，如果在编码过程中发生了有效的模式分离，则可以解决这种干扰。本研究通过操纵累积概念干扰指数来检验类别内编码干扰对记忆物体表征保真度的影响，该指数代表了容量和相似性的并发影响。通过在识别任务中测量目标和诱饵之间的视觉相似性对记忆辨别力的影响，进一步评估了记忆辨别力的准确性。我们的研究结果表明，随着干扰的增加，对目标的正确识别显著下降。累积干扰以及与目标的视觉相似性也会对诱饵的正确拒绝产生负面影响。然而，最有趣的是，当在较低而非较高的干扰下对物体进行编码时，对带有视觉相似诱饵的目标进行记忆辨别更加困难。这些发现反驳了干扰对物体表征保真度的简单累加影响，为 LTVM 中的干扰提供了更精细、多因素的理解。
