Liu Zejun, Zhu Yajun, Song Xiuping
School of psychology, Shanghai Normal University, Shanghai, China.
Lab for Educational Big Data and Policymaking, Ministry of Education, Shanghai Normal University, Shanghai, China.
Cogn Affect Behav Neurosci. 2025 Jan 6. doi: 10.3758/s13415-024-01251-3.
The viewpoint that unitization provides a possibility of increasing the contribution of familiarity to associative memory has been widely accepted, but its effects on associative memory and recollection remain controversial. The current study aims to explain these mixed results by considering a potential moderator: changes in the level of unitization from encoding to retrieval phases. During the encoding phase, participants learned the related and unrelated picture pairs (i.e., high vs. low levels of unitization). Subsequently, they needed to distinguish between the intact and rearranged pairs during retrieval, where, in these rearranged pairs, the level of unitization from encoding to retrieval phases may or may not change. Meanwhile, the scalp electroencephalographic activity (EEG) was recorded. The results showed a significant familiarity-related FN400 old/new effect for related picture pairs alone, which supported the above viewpoint. However, its impact on the associative memory and recollection-related LPC old/new effects varied with the level of unitization changes-specifically, under the unchanged conditions. Although related pairs elicited significant FN400 and LPC old/new effects, the differences in these old/new effects and associative memory between the related and unrelated picture pairs were not significant. Conversely, under the changed conditions, related picture pairs not only elicited significantly larger FN400 and LPC old/new effects but also improved associative memory more than unrelated picture pairs. These findings not only clarify some of the inconsistencies in the literature concerning the impact of unitization on associative memory but also suggest that unitization affects the contributions of familiarity and recollection to associative memory differently, its effectiveness varying with the level of unitization changes.
单元化增加了熟悉度对联想记忆贡献的可能性这一观点已被广泛接受，但其对联想记忆和回忆的影响仍存在争议。当前研究旨在通过考虑一个潜在的调节因素来解释这些混合结果：从编码阶段到检索阶段单元化水平的变化。在编码阶段，参与者学习相关和不相关的图片对（即高单元化水平与低单元化水平）。随后，他们在检索过程中需要区分完整的和重新排列的图片对，在这些重新排列的图片对中，从编码阶段到检索阶段的单元化水平可能会改变，也可能不会改变。同时，记录头皮脑电图活动（EEG）。结果表明，仅相关图片对存在显著的与熟悉度相关的FN400新旧效应，这支持了上述观点。然而，其对联想记忆和与回忆相关的LPC新旧效应的影响随单元化变化水平而变化——具体而言，在不变的条件下。尽管相关图片对引发了显著的FN400和LPC新旧效应，但相关和不相关图片对之间这些新旧效应和联想记忆的差异并不显著。相反，在变化的条件下，相关图片对比不相关图片对不仅引发了显著更大的FN400和LPC新旧效应，而且联想记忆改善得更多。这些发现不仅澄清了文献中关于单元化对联想记忆影响的一些不一致之处，还表明单元化对熟悉度和回忆对联想记忆的贡献影响不同，其有效性随单元化变化水平而变化。
