Different involuntary mechanisms underlie priming and LOP effects in stem completion tests

The role of intentional retrieval, involuntary conscious memory, and lexical processing in priming and levels‐of‐processing (LOP) effects in stem completion tests was investigated in three experiments. First, Experiment 1 provided strong evidence against the intentional retrieval hypothesis for the implicit LOP effects. LOP effects in the explicit test were dependent on intertrial interval at test, whereas LOP effects in the implicit test were not. Second, support was provided for the involuntary conscious memory hypothesis. Implicit memory (priming) was associated with awareness in all three experiments and the implicit LOP effect was associated with awareness in two of the three experiments. Third, it was concluded that lexical processing per se played a limited role in both priming and implicit LOP effects. Although priming was sensitive to normative rates of production in Experiment 1 and the number of solutions in all three experiments, it was insensitive to frequency manipulations. The LOP effect was insensitive to number of solutions, normative rates of production, and frequency manipulations. In addition, LOP and priming effects were uncorrelated in the implicit memory tests. It was concluded that production processes (e.g., Gabrieli et al., 1999), rather than lexical processes, played a crucial role in stem completion priming. In contrast, the LOP effect was attributed to the involuntary interaction of episodic and perceptual memory.     

Different involuntary mechanisms underlie priming and LOP effects in stem completion tests

The role of intentional retrieval, involuntary conscious memory, and lexical processing in priming and levels-of-processing (LOP) effects in stem completion tests was investigated in three experiments. First, Experiment 1 provided strong evidence against the intentional retrieval hypothesis for the implicit LOP effects. LOP effects in the explicit test were dependent on intertrial interval at test, whereas LOP effects in the implicit test were not. Second, support was provided for the involuntary conscious memory hypothesis. Implicit memory (priming) was associated with awareness in all three experiments and the implicit LOP effect was associated with awareness in two of the three experiments. Third, it was concluded that lexical processing per se played a limited role in both priming and implicit LOP effects. Although priming was sensitive to normative rates of production in Experiment 1 and the number of solutions in all three experiments, it was insensitive to frequency manipulations. The LOP effect was insensitive to number of solutions, normative rates of production, and frequency manipulations. In addition, LOP and priming effects were uncorrelated in the implicit memory tests. It was concluded that production processes (e.g., Gabrieli et al., 1999), rather than lexical processes, played a crucial role in stem completion priming. In contrast, the LOP effect was attributed to the involuntary interaction of episodic and perceptual memory.     

Effects of depth-of-processing and ageing on word-stem and word-fragment implicit memory tasks: Test of the lexical-processing hypothesis

The joint effects of depth-of-processing and age on repetition priming in implicit memory tests of word-fragment completion (WFC) and word-stem completion (WSC) were investigated. The experiment consisted of three study tasks (perceptual, lexical, and semantic) and four memory conditions: implicit (WSC and WFC) and explicit (WS cued recall and WF cued recall). In the WSC condition, semantic and lexical study processing produced equal priming, both superior to the perceptual study processing, whereas the WFC test showed equal priming for these three study conditions. This finding provides clear evidence, consistent with the lexical-processing hypothesis, that depth-of-processing in WSC priming reflects a lexical rather than a semantic process. It also provides support for the view that WSC and WFC involve different processes. However, there was no evidence of an age effect on either of these two implicit tasks. The data also revealed an overall significant effect of age and depth-of-processing, and an interaction between these variables on explicit cued recall tasks, indicating that older adults benefited less than younger ones from a deep encoding condition.     

提取干扰对知觉和概念启动的影响

通过学习—测验范式,分别以词汇判断、语义分类任务为测验,探讨提取干扰对不同识别式记忆的影响差异。结果发现,实验1验证了识别式知觉内隐记忆的提取干扰效应,实验2发现识别式概念内隐记忆在提取干扰下也明显降低;两个实验启动量联合分析发现,相比无干扰条件,概念启动比知觉启动受到提取干扰的破坏更大。上述结果说明识别式内隐记忆的提取干扰具有普遍性,提取干扰产生了不同识别式内隐记忆之间的分离,识别式概念内隐记忆更容易受到提取干扰的影响。     

提取干扰对内隐记忆的影响

以往研究多认同内隐记忆不会受到干扰的影响,但主要集中于编码时的干扰不会影响随后的内隐记忆提取成绩,而对于提取时的干扰是否也不会影响内隐记忆成绩仍存在疑义。该文在实验1采用学习-测验范式,通过在提取阶段设置同时干扰任务进一步考察提取干扰与内隐记忆的关系,结果表明提取干扰下并未发现明显的启动效应,即提取干扰破坏了内隐记忆。为进一步探讨内隐记忆的提取干扰效应是否源于记忆与干扰刺激同时呈现所引起的知觉表征竞争,实验2改变了记忆与干扰刺激的呈现顺序,结果表明不论干扰刺激在记忆项目之前或之后呈现,启动效应均受到影响。相比之下,提取干扰对再认成绩的影响并不明显(实验3)。上述结果表明,内隐记忆的提取干扰效应是源于一般认知资源的竞争,在提取过程中任何能够产生认知资源竞争的变量设置都可能会削减内隐测验中的启动效应。     

False memories and lexical decision: even twelve primes do not cause long-term semantic priming

Semantic priming effects are usually obtained only if the prime is presented shortly before the target stimulus. Recent evidence obtained with the so-called false memory paradigm suggests, however, that in both explicit and implicit memory tasks semantic relations between words can result in long-lasting effects when multiple 'primes' are presented. The aim of the present study was to investigate whether these effects would generalize to lexical decision. In four experiments we showed that even as many as 12 primes do not cause long-term semantic priming. In all experiments, however, a repetition priming effect was obtained. The present results are consistent with a number of other results showing that semantic information plays a minimal role in long-term priming in visual word recognition.     

任务转换中惯性激活对内隐记忆的影响：来自ERPs的证据

以往研究认为内隐记忆具有不受干扰影响的自动化加工特征,其证据主要来自于对内隐记忆编码过程的研究。最近已有多项研究发现,内隐记忆受提取过程中的干扰影响,但对这一现象的产生机制目前仍尚无定论。本研究根据任务转换相关理论,通过将go/no-go范式引入干扰任务,探讨提取过程中前置干扰对内隐记忆产生影响的内在机制。结果表明,前置的干扰任务产生惯性激活时,后续的内隐记忆任务会受到影响,即启动效应降低。对惯性激活进行抑制后,随后的内隐记忆则不受影响。并且,在内隐记忆相关的N400成分上得到了与行为数据一致的结果,即在no-go干扰下,获得的N400新旧效应,在go干扰下却未被发现。研究结果证明,提取干扰对内隐记忆的影响主要由干扰任务与内隐记忆任务对认知资源的竞争导致。     

加工水平及词对类型在新异联系形成中的作用

该研究采用过程分离方法和知觉辨认方法探讨不同加工水平和词对类型在新异联系形成中的作用。结果表明,深加工是形成非相关词对间联想启动的条件之一。另外,具体词对的联想启动没有表现出加工水平效应,出现了内隐和外显记忆的分离现象,提示不同的词对类型与加工水平间存在着交互作用,当联系程度较紧时,并不一定需要语义加工,而联系程度不紧时,语义加工则是必要的。     

提取干扰对不同类型内隐记忆的影响

以往研究关于提取阶段的干扰是否会影响内隐记忆存在着异义, 其中一个重要因素可能源于所采用的内隐记忆测验类型的差异。本研究采用学习-测验范式, 通过4个实验, 分别考察了提取干扰对识别式知觉内隐测验、识别式概念内隐测验、产生式知觉内隐测验和产生式概念内隐测验的影响, 以期对提取干扰和内隐记忆之间的关系有着更全面的了解。结果表明: (1)词汇判断任务(识别式知觉)和语义分类任务(识别式概念)的启动效应在提取干扰下消失了, (2)而产生式词汇判断任务(产生式知觉)和产生式语义分类任务(产生式概念)在提取干扰下仍发现了明显的启动效应, 但与无干扰条件相比, 启动效应量也有着明显的减少。由此可见, 不同类型的内隐记忆都会受到提取干扰的影响, 相比于产生式启动, 识别式启动更容易受到提取干扰的破坏。     

非熟练中—英双语者跨语言长时重复启动效应

采用跨语言长时重复启动研究范式进一步探讨非熟练中－英双语者的记忆表征模型。被试为华南师范大学大一本科生共140名。实验自变量是语言条件（同语言和跨语言）和学习状况（学习过的和未学习过的）,实验因变量是单词判断的反应时和正确率。实验1中被试在学习和测验阶段都完成概念任务,结果表明获得了跨语言长时重复启动效应。实验2中被试在学习和测验阶段完成词汇任务,结果表明没有获得跨语言长时重复启动效应。实验3中被试在学习阶段完成概念任务,在测验阶段完成词汇任务,结果表明没有获得跨语言长时重复启动效应。实验4中在学习阶段的概念任务中呈现汉语单字词,在测验阶段的词汇任务中呈现英语翻译对等词,结果表明没有获得跨语言长时重复启动效应。总的实验结果表明,在基于内隐记忆的跨语言重复启动的范式下,非熟练中－英双语者的记忆表征支持概念表征共享、词汇表征分离的观点。更重要的是,非熟练中－英双语者需要经由汉语翻译对等词的词汇表征,才能通达英语单词的概念表征,支持了词汇连接模型的观点     

编码与提取干扰对内隐和外显记忆的非对称性影响

以往研究表明在外显记忆中,编码与提取加工存在着非对称性,但在内隐记忆中,二者的关系并不明确,因此实验采用“学习-再认”范式,考察在编码或提取中分别附加的干扰任务对词汇判断或再认产生的影响。结果证实编码与提取干扰对内隐或外显记忆都具有非对称性的影响,但又存在着差异,即编码干扰会导致随后外显记忆成绩显著减少,而提取干扰对其影响较小,相反,编码干扰对随后内隐测验中启动效应的影响较小,但提取干扰会破坏启动效应,从而为内隐记忆和外显记忆的分离提供了进一步的证据     

概念内隐记忆中的注意促进效应

Swallow和Jiang (2010)最早发现, 编码时的目标探测会促进同时呈现的背景信息在随后记忆测验中的表现, 并将这一现象称为注意促进效应(Attentional Boost Effect, ABE)。随后研究发现这一现象并不会出现在概念内隐测验中, 由此提出目标探测主要促进的是背景信息的知觉加工, 而非语义加工。本研究通过3个实验, 操纵了对背景信息的编码加工类型(知觉加工或概念加工)。结果发现, 当与目标探测同时进行的是对背景信息的概念加工任务, 则ABE会出现在随后的概念内隐测验中。反之, 当对背景信息进行的是知觉加工任务时, 则ABE会出现在随后的知觉内隐测验而不是概念内隐测验中。这些结果表明, 目标探测既可能促进背景信息的知觉加工, 也可能促进背景信息的语义加工, 但只有在目标探测下背景信息的编码加工与随后内隐测验中所依赖的提取加工具有一致性, 才会产生ABE。     

内隐与外显记忆的编码与提取非对称性关系

实验采用“学习-测验”范式, 考察在编码或提取中分别附加的干扰任务对内隐测验或外显测验中获得的ERP新旧效应产生的影响。结果表明, 在内隐测验中, 编码干扰对随后测验中的ERP新旧效应没有产生影响, 而提取干扰却改变了300~500ms新旧效应的脑区位置, 破坏了500~700ms新旧效应; 与之相反, 在外显测验中, 编码干扰破坏了500~700ms新旧效应, 而提取干扰对这一效应没有产生影响, 即编码与提取干扰对内隐或外显测验中的ERP新旧效应都产生了非对称性的影响, 但又存在着差异, 从而为两种记忆在编码与提取加工的关系上存在的分离现象提供了神经生理方面的证据。     

Involuntary aware memory enhances priming on a conceptual implicit memory task

This study investigated the role of involuntary aware memory (phenomenological awareness of the study episode) on a conceptual implicit memory task. Subjects studied words under levels of processing conditions (LOP: nonsemantic vs. semantic) and then received a category exemplar generation priming task. Subjects were either aware or unaware of the study test relationship. Subjects who were study test aware showed more priming for semantic study than subjects who were study test unaware, thus producing an LOP dissociation between them. The findings suggest that involuntary aware memory can enhance performance on conceptual implicit memory tasks, thus having theoretical implications for implicit and explicit memory.     

Explicit contamination in “implicit” memory for new associations

In one view of implicit memory, priming arises from modification of preexisting representations; however, the role of such representations is currently in doubt following findings of implicit memory for newly formed associations. Closer consideration of studies reporting this effect, and of others that have failed to obtain it, suggests that such priming might result from the employment of explicit memory strategies. With measures designed to permit exclusion of such strategies, three experiments using lexical decision and stem-completion tasks found no evidence of truly implicit memory for unrelated pairs. Instead, priming was found only in those subjects (50% of the total in one experiment) who reported using explicit memory in stem completion. Contrary to previous conclusions, the results indicate a role for established representations in explaining implicit memory.     

Word priming without awareness: A new approach to circumvent explicit memory contamination

A major methodological limitation arising in the experimental study of implicit memory is that tasks that are characterized as implicit memory tests can be seriously contaminated by the use of covert explicit memory strategies. Given the evidence indicating that brief presentation of words (below the awareness threshold of subjects) can produce semantic priming, we wondered whether rapid visual presentation of primed words might provide an avenue to produce word priming without explicit memory contamination. Normal subjects were tested for word priming on a speeded category membership decision task. Explicit or implicit encoding procedures were used in four different experiments. Results demonstrated that brief presentation of words can indeed offer a means of producing word priming in absence of explicit recognition or recall of the primed words presented during the study phase. They also showed that such priming is equivalent in degree to the priming measured when using either a conventional implicit memory design or an explicit encoding procedure prior to the study of the primes.     

Priming in implicit memory tasks: prior study causes enhanced discriminability, not only bias

R. Ratcliff and G. McKoon (1995, 1996, 1997; R. Ratcliff, D. Allbritton, & G. McKoon, 1997) have argued that repetition priming effects are solely due to bias. They showed that prior study of the target resulted in a benefit in a later implicit memory task. However, prior study of a stimulus similar to the target resulted in a cost. The present study, using a 2-alternative forced-choice procedure, investigated the effect of prior study in an unbiased condition: Both alternatives were studied prior to their presentation in an implicit memory task. Contrary to a pure bias interpretation of priming, consistent evidence was obtained in 3 implicit memory tasks (word fragment completion, auditory word identification, and picture identification) that performance was better when both alternatives were studied than when neither alternative was studied. These results show that prior study results in enhanced discriminability, not only bias.     

Effects of verbal labeling and exposure duration on implicit memory for visual patterns.

The present study investigated the role of verbal labeling and exposure duration in implicit memory for novel visual patterns. Encoding condition was varied in Experiment 1. Two encoding conditions discouraged verbal labeling and a third required it. In Experiment 2, exposure duration was manipulated to determine whether a new memory representation could be formed after a single 1-s exposure. The results suggest that verbal labeling is not necessary to support priming. Type of encoding did not affect implicit memory, but had a pronounced effect on explicit memory. Furthermore, a single 1-s exposure was sufficient to support priming, and priming was not further enhanced by longer stimulus exposures. In contrast, recognition performance was enhanced by a longer stimulus duration. Thus, priming effects with these novel figures are likely to be supported by newly acquired representations rather than by preexisting memory representations.