Ding Huiyu, Whitlock Jonathon, Sahakyan Lili
University of Illinois Urbana-Champaign, Champaign, Illinois, USA.
Mississippi State University, Starkville, Mississippi, USA.
Psychophysiology. 2025 Aug;62(8):e70119. doi: 10.1111/psyp.70119.
Studies have revealed that information can be intentionally forgotten when instructed, commonly studied in the laboratory with the directed forgetting (DF) procedure. The current investigation examined pupillometric signals associated with intentional forgetting, as the pupil reflects the activity in the locus coeruleus-norepinephrine (LC-NE) system that is functionally involved in the neural correlates of intentional forgetting. Experiment 1 employed an item-method DF paradigm, where participants were presented with natural scenes, each followed by a memory cue to either remember (R) or forget (F) that scene. At test, participants were asked to judge whether the presented scene was the original studied version (i.e., "Old") or a mirrored variant (i.e., "Lure"). By comparing pupil dilation during test trials between R-cued and F-cued scenes for both hit and miss trials, we found greater pupil dilation for F-cued miss trials compared to R-cued miss trials, but no difference in pupil dilation between the cue conditions for hit trials. This suggests a unique pupillometric pattern linked to successful intentional forgetting. Experiment 2 was aimed at assessing if memory strength differences could provide an explanation for the observed effect. Instead of DF cues, we manipulated memory strength by repeating a subset of scenes, thereby converting all study items into R-cued items with different degrees of familiarity. We observed no difference in pupil dilation between strongly encoded and weakly encoded scenes at test, indicating that encoding strength by itself did not explain the difference in pupil dilation resulting from intentional forgetting. Together, these findings provide novel evidence that pupil fluctuations during retrieval index successful intentional forgetting.
研究表明，当接到指令时，信息可以被有意遗忘，这一现象通常在实验室中通过定向遗忘（DF）程序进行研究。当前的调查研究了与有意遗忘相关的瞳孔测量信号，因为瞳孔反映了蓝斑-去甲肾上腺素（LC-NE）系统的活动，该系统在功能上参与了有意遗忘的神经关联。实验1采用了项目法DF范式，向参与者呈现自然场景，每个场景之后都会出现一个记忆提示，指示他们记住（R）或忘记（F）该场景。在测试时，要求参与者判断呈现的场景是原始学习版本（即“旧”）还是镜像变体（即“诱饵”）。通过比较命中和未命中试验中R提示和F提示场景在测试试验期间的瞳孔扩张情况，我们发现F提示未命中试验的瞳孔扩张比R提示未命中试验更大，但命中试验的提示条件之间瞳孔扩张没有差异。这表明存在一种与成功有意遗忘相关的独特瞳孔测量模式。实验2旨在评估记忆强度差异是否可以解释观察到的效应。我们没有使用DF提示，而是通过重复一部分场景来操纵记忆强度，从而将所有学习项目转换为具有不同熟悉程度的R提示项目。我们在测试中观察到，强编码和弱编码场景之间的瞳孔扩张没有差异，这表明编码强度本身并不能解释有意遗忘导致的瞳孔扩张差异。总之，这些发现提供了新的证据，表明检索过程中的瞳孔波动指示了成功的有意遗忘。
