Liu Tzu-Ling, Chen Nai-Feng, Cheng Shih-Kuen
Institute of Cognitive Neuroscience, National Central University, Taiwan.
Institute of Cognitive Neuroscience, National Central University, Taiwan.
Biol Psychol. 2017 Feb;123:15-24. doi: 10.1016/j.biopsycho.2016.11.012. Epub 2016 Nov 24.
Emotional items are often remembered more clearly than neutral items. However, whether stimuli embedded in an emotional context are more resistant to directed forgetting than those presented in a neutral context remains unclear. This question was tested by recording event-related potentials (ERPs) in an item-method directed forgetting paradigm involving neutral words that were embedded in neutral or negative contexts. During the study phase, participants were asked to associate a neutral word with a negative or neutral picture. A remember (R) or forget (F) cue was then designated to indicate whether the word was a to-be-remembered (TBR) or to-be-forgotten (TBF) word. In the test phase, participants were asked to identify all previously presented old words regardless of the R/F cues. The behavioral results indicated a significant interaction between the valence of the encoding contexts and the R/F cues. The hit rate was lower for the TBR words encoded in negative contexts relative to those encoded in neutral contexts. No such valence effect was observed in the hit rates of the TBF words. For the ERP data, the R cues elicited a P3b-like effect that has been linked to the selective rehearsal of the TBR items. This effect was more sustained in the negative encoding context than in the neutral context. The F cues elicited a frontal positivity that has been linked to the active inhibition of the TBF words; however, this positivity was not modulated by the valence of the encoding context. The sustained P3b-like effect for the R cues in the negative encoding context might reflect a compensative encoding for the TBR words caused by the attention-capturing negative contexts. Therefore, we argue that the emotional context affected the selective elaboration of the TBR words; however, we also argue that there was no supportive evidence of an emotional effect on the forgetting of TBF items.
与中性项目相比，情感项目往往更容易被清晰地记住。然而，嵌入情感背景中的刺激是否比处于中性背景中的刺激更能抵抗定向遗忘，目前尚不清楚。在一项项目法定向遗忘范式中，通过记录事件相关电位（ERP）来测试这个问题，该范式涉及嵌入中性或负面背景中的中性词。在学习阶段，要求参与者将一个中性词与一张负面或中性图片相关联。然后指定一个记住（R）或忘记（F）线索，以表明该词是一个要记住（TBR）还是要忘记（TBF）的词。在测试阶段，要求参与者识别所有之前呈现的旧词，无论R/F线索如何。行为结果表明，编码背景的效价与R/F线索之间存在显著交互作用。相对于在中性背景中编码的TBR词，在负面背景中编码的TBR词的命中率较低。在TBF词的命中率中未观察到这种效价效应。对于ERP数据，R线索引发了一种类似于P3b的效应，该效应与TBR项目的选择性复述有关。这种效应在负面编码背景中比在中性背景中更持久。F线索引发了一种额叶正电位，该电位与对TBF词的主动抑制有关；然而，这种正电位并未受到编码背景效价的调节。负面编码背景中R线索的持续P3b样效应可能反映了由吸引注意力的负面背景对TBR词造成的补偿性编码。因此，我们认为情感背景影响了TBR词的选择性加工；然而，我们也认为没有支持情感对TBF项目遗忘产生影响的证据。
