Processes of conscious and unconscious memory: evidence from current research on dissociation of memories within a test

The processes of conscious memory (CM) and unconscious memory (UM) are explored, based on the results of the current and previous studies in which the 2 forms of memory within a test were separated by either the process dissociation or metacognition-based dissociation procedure. The results assessing influences of shallow and deep processing, association, and self-generation on CM in explicit and implicit tests are taken as evidence that CM in a test is driven not only conceptually but also by the driving nature of the test, and CM benefits from an encoding condition to the extent that information processing for CM recapitulates that engaged in the encoding condition.Those influences on UM in explicit and implicit tests are taken to support the view that UM in a test is driven by the nature of the test itself, and UM benefits from an encoding condition to the extent that the cognitive environments at test and at study match to activate the same type of information (e.g., visual, lexical, or semantic) about memory items or the same content of a preexisting association or categorical structure.     

一致性、相关性对记忆生存优势效应的影响

对词语进行生存加工能提高记忆成绩,这种记忆的生存优势效应已得到不少研究的验证,且大多数研究表明生存优势是一种独特的编码方式(Nairne&Pandeirada,2011)。但是,Butler等人(2009)的研究结果表明实验中生存加工带来的记忆优势可能是一致性效应(即编码任务与编码的材料之间具有一致性)的作用。本文在2个实验中选用与生存和抢劫加工条件相关程度不同的词(高中低)为实验材料,采用生存加工、抢劫加工、愉悦度和有意学习为实验条件,研究一致性和相关性在记忆生存优势中的作用。结果发现:(1)生存条件下的记忆效果显著优于愉悦度条件和有意学习条件,这说明的确存在记忆的生存优势效应;(2)高生存相关词在生存加工条件下产生了记忆优势,而中、低生存相关词在2种加工条件下记忆成绩差异不显著,这说明加工条件的一致性只在一定程度上影响着记忆的生存优势效应;(3)词语自身的生存相关性没有表现出较强的记忆优势,当然这也可能与实验材料的词频有关。研究结果支持了Nairne和Pandeirada(2011)的观点。     

联想启动与知觉启动的比较研究

采用快速命名方法探讨不同加工水平对联想启动效应的影响。被试分别在深、浅加工条件下学习一系列颜色词,然后完成颜色命名和再认任务,并设立词命名任务,以比较联想启动和知觉启动的异同。结果表明,在颜色命名任务中,深、浅加工条件下均可形成对颜色词的启动效应,但浅加工条件下的再认成绩明显低于深加工,出现了联想启动和再认的分离现象。词命名表现出与颜色命名相似的结果,但它们在有意识回忆方面仍存在一定的差异,提示知觉表征系统单独并不能支持联想启动,联想启动可能是多个记忆系统共同作用的结果。     

错误记忆的产生是否依赖对词表的有意加工：无意识激活的证据

使用DRM范式考察了错误记忆产生过程中无意识激活的存在与否。通过操纵实验任务和呈现方式,导致被试对学习词表的无意加工和不同水平的有意加工。结果发现,无意加工时所产生的对关键诱饵的无意识激活足以导致错误记忆效应,说明对词表的有意加工并非错误记忆产生所必需。随着对词表有意加工水平的提高,多次无意识激活的累积可导致增强的错误记忆效应,且表现出与真实记忆的共变,而阻断连续激活累积的因素可有效降低错误记忆     

Eye movements,word familiarity,and vocabulary acquisition

Two experiments examined the effects of word familiarity on word recognition and text comprehension during silent reading. Readers' eye movements were monitored as they read sentences containing words that varied in familiarity as assessed by printed estimates of word frequency, subjective ratings of familiarity, and a multiple‐choice test of meaning knowledge. Effects of word frequency were unaffected by differences in subjective familiarity rating for high frequency words. Differential effects of familiarity rating were observed in low frequency conditions. In addition, processing time on high and low frequency words did not differ when familiarity was held constant for moderately familiar words. Readers spent more initial processing time on novel words than familiar words. Performance on a vocabulary test administered after the reading session demonstrated that readers successfully acquired and retained new word meanings. Finally, reanalysis of word processing time as a function of vocabulary test performance demonstrated a systematic relationship between online processing patterns and memory for novel word meaning.     

错误记忆的自我参照效应：易化的作用

采用DRM范式,设置三种参照对象条件（自我、他人和中性参照）,考察错误记忆是否存在自我参照效应。结果发现：（1）与正确记忆一样,错误记忆中亦存在自我参照效应;（2）无论是正确记忆还是错误记忆,自我参照条件下的回忆成分均显著多于他人参照和中性参照,但熟悉性成分在三种不同参照对象条件下没有显著差异;（3）当词表中学习项目由分组呈现变为随机呈现时,错误记忆的自我参照效应仍稳定存在。结果揭示,自我参照效在促进正确记忆的同时,亦可易化错误记忆效应。     

Recognition with and without identification: dissociative effects of meaningful encoding

In a series of four experiments, the effects of levels of processing and generation on the recognition of identified versus unidentified word fragments were examined. After studying a list of words, participants took a word fragment completion test in which half of the fragments came from studied words and half came from nonstudied words. Regardless of whether they could complete a given fragment, the participants were asked to rate the likelihood that it came from a studied word. Recognition of identified fragments was best whenever the focus of the encoding task was on meaning. Recognition of unidentified fragments did not benefit from meaningful encoding in any of the experiments reported here but did benefit from generation. It is suggested that whereas recognition with identification involves the use of meaning, recognition without identification involves the use of abstract orthographic information in memory.     

不同加工与记忆编码关系的ERP研究

通过事件相关电位(ERPs)记录,探讨了深、浅2种加工与记忆编码的相互关系。研究结果表明,（1）在深、浅两种加工条件下,首次使用汉字材料,获得了ERP相继记忆效应（Dm),随后再认正确的ERPs比随后再认不正确的ERPs有更大的晚正成分。（2）深加工的Dm效应始于N2波的前支（230－280ms)和N2波之后（395－800ms);而浅加工的Dm效应发生在345－490ms之间。深、浅加工的Dm效 涉及不同的脑区,这一结果支持深、浅两种加工的Dm效应可能是分离的结论。     

Evidence for several components of word familiarity

Familiarity with a word can be divided into two main components: familiarity with the form of the word (due to both its lexicality and its specific form) and familiarity with its meaning. In this study, ratings of familiarity were compared for words whose meaning was unknown to participants (UM words), for words of known meaning (KM words), and for unknown words (U words). Linguistic and experiential frequencies were equivalent. Rated familiarity was lower for UM than KM words and even lower for U words. Next, we built pseudowords from these stimuli by changing one letter and submitted them to two familiarity rating tasks that differed in the nature of the additional stimuli: either only nonwords or nonwords plus words. It was assumed that familiarity ratings would be lower for pseudowords built from UM words than for pseudowords built from KM words. The data were consistent with this assumption, and ratings depended on the initial categories of stimuli. These results support the view that usual word familiarity has two components, familiarity with form and familiarity with meaning, and a double source, processing of word form and processing of word meaning. The full set of these materials and norms may be downloaded from www.psychonomic.org/archive.     

Implicit memory in spelling from word images

Summary A series of experiments is reported concerning implicit memory in imaginal processing. In the standard condition, subjects had to encode word images before spelling a word. The spelling task was repeated in the test phase with the same words and with additional control words. Spelling times were registered after the image encoding. Implicit memory has been detected if repeated words can be spelled faster than control words. Experiment 1 showed that levels of processing manipulations (such as the additional generation of meaning images at encoding or variations in word concreteness) favor explicit memory, but do not show up in implicit memory. Experiment 2 demonstrated that implicit memory disappears if spelling at encoding took place on visually present words. Experiment 3 investigated whether the focusing of specific letter positions within the image may contribute to the effect, but this was not found. According to a processing view that underlies our task analysis, implicit memory depends on transfer-appropriate processing and is attributed to processes of image encoding or generation and image reconstruction or regeneration.     

One process is not enough! A speed-accuracy tradeoff study of recognition memory

Speed-accuracy tradeoff (SAT) methods have been used to contrast single- and dual-process accounts of recognition memory. In these procedures, subjects are presented with individual test items and are required to make recognition decisions under various time constraints. In this experiment, we presented word lists under incidental learning conditions, varying the modality of presentation and level of processing. At test, we manipulated the interval between each visually presented test item and a response signal, thus controlling the amount of time available to retrieve target information. Study— test modality match had a beneficial effect on recognition accuracy at short response-signal delays (≤300msec). Conversely, recognition accuracy benefited more from deep than from shallow processing at study only at relatively long response-signal delays (≥300 msec). The results are congruent with views suggesting that both fast familiarity and slower recollection processes contribute to recognition memory.     

记忆编码与特异性效应之间关系的ERP研究

通过事件相关电位（ERPs）探讨了在“学习–再认”模式条件下的记忆编码与特异性效应之间的关系。选择首要特异性特征为深、浅加工,次要特异性特征为高、低词频。研究结果表明,（1）行为数据支持了低频词的再认比高频词更精确;深加工的再认比浅加工更精确,并且深加工存在着显著的字频效应,浅加工没有显著的字频效应。（2）低频词比高频词有更大的ERP晚正成分（LPC）;在低频词条件下,存在着显著的相继记忆效应,随后再认正确的ERPs比随后再认不正确的ERPs更正。因此,加工方式和词频间接地影响着记忆编码的形成。     

Generation difficulty and memory for source

The role of the word predictability from sentence context for reality monitoring and external source monitoring was examined in two experiments. In a reality-monitoring task, discrimination of an internal source was better in the hard than in the easy condition. It is probable that extra cognitive operations engaged during word generation in the hard condition were effective cues for reality-monitoring judgements. In contrast, in an external source-monitoring task (recognition memory of item's colour), the hard condition resulted in worse source memory for generated words than did the easy condition. This result is consistent both with an item-context trade-off hypothesis and a processing hypothesis. Greater effort involved at the time of generation might limit resources available for encoding of an external source. It is also possible that for generated words, the hard condition promoted conceptual processing instead of perceptual processing; therefore the item's colour was not effectively encoded.     

Recollective performance advantages for implicit memory tasks

A commonly held assumption is that processes underlying explicit and implicit memory are distinct. Recent evidence, however, suggests that they may interact more than previously believed. Using the remember–know procedure the current study examines the relation between recollection, a process thought to be exclusive to explicit memory, and performance on two implicit memory tasks, lexical decision and word stem completion. We found that, for both implicit tasks, words that were recollected were associated with greater priming effects than were words given a subsequent familiarity rating or words that had been studied but were not recognised (misses). Broadly, our results suggest that non-voluntary processes underlying explicit memory also benefit priming, a measure of implicit memory. More specifically, given that this benefit was due to a particular aspect of explicit memory (recollection), these results are consistent with some strength models of memory and with Moscovitch's (2008) proposal that recollection is a two-stage process, one rapid and unconscious and the other more effortful and conscious.     

Recalling taboo and nontaboo words

People remember emotional and taboo words better than neutral words. It is well known that words that are processed at a deep (i.e., semantic) level are recalled better than words processed at a shallow (i.e., purely visual) level. To determine how depth of processing influences recall of emotional and taboo words, a levels of processing paradigm was used. Whether this effect holds for emotional and taboo words has not been previously investigated. Two experiments demonstrated that taboo and emotional words benefit less from deep processing than do neutral words. This is consistent with the proposal that memories for taboo and emotional words are a function of the arousal level they evoke, even under shallow encoding conditions. Recall was higher for taboo words, even when taboo words were cued to be recalled after neutral and emotional words. The superiority of taboo word recall is consistent with cognitive neuroscience and brain imaging research.     

Comparative difficulty and the strategic regulation of accuracy: The impact of test-list context on monitoring and meta-metacognition

A growing body of research has shown that context manipulations can have little or no impact on accuracy performance, yet still significantly influence metacognitive performance. For example, participants in a test-list context paradigm study one list of words with a medium levels-of-processing task and a second word list with either a shallow or deep task: Recognition for medium words does not differ across conditions, however medium words are significantly more likely to be labeled as “remembered” (vs. merely familiar) if they had been studied with a shallow word list (Bodner & Lindsay, 2003). The goal of the current studies was to extend the test-list context paradigm to strategic regulation (report/withhold recognition test), and broaden it to incorporate different types of stimuli (i.e., face stimuli in place of a medium word list). The paradigm also was modified to include separate answer (studied/new) confidence and decision (report/withhold) confidence ratings at test. Results showed that context did not impact recognition accuracy for faces across the context conditions, however participants were more likely to report (i.e., volunteer) their face responses if they had studied the shallow word list. The results also demonstrated a difference between answer confidence and decision confidence, and the pattern of this difference depended on whether responses were reported or withheld (Experiment 1). Overall, the data are presented as support for the functional account of memory, which views memory states as inferential and attributional rather than static categories.     

The origins of levels-of-processing effects in a conceptual test: evidence for automatic influences of memory from the process-dissociation procedure

In three experiments, we explored automatic influences of memory in a conceptual memory task, as affected by a levels-of-processing (LoP) manipulation. We also explored the origins of the LoP effect by examining whether the effect emerged only when participants in the shallow condition truncated the perceptual processing (the lexical-processing hypothesis) or even when the entire word was encoded in this condition (the conceptual-processing hypothesis). Using the process-dissociation procedure and an implicit association-generation task, we found that the deep encoding condition yielded higher estimates of automatic influences than the shallow condition. In support of the conceptual processing hypothesis, the LoP effect was found even when the shallow task did not lead to truncated processing of the lexical units. We suggest that encoding for meaning is a prerequisite for automatic processing on conceptual tests of memory.     

Generation difficulty and memory for source

The role of the word predictability from sentence context for reality monitoring and external source monitoring was examined in two experiments. In a reality-monitoring task, discrimination of an internal source was better in the hard than in the easy condition. It is probable that extra cognitive operations engaged during word generation in the hard condition were effective cues for reality-monitoring judgements. In contrast, in an external source-monitoring task (recognition memory of item's colour), the hard condition resulted in worse source memory for generated words than did the easy condition. This result is consistent both with an item–context trade-off hypothesis and a processing hypothesis. Greater effort involved at the time of generation might limit resources available for encoding of an external source. It is also possible that for generated words, the hard condition promoted conceptual processing instead of perceptual processing; therefore the item's colour was not effectively encoded.     

Intelligence moderates the benefits of strategy instructions on memory performance: an adult-lifespan examination

Whether older adults can compensate for their associative memory deficit by using memory strategies efficiently might depend on their general cognitive abilities. This study examined the moderating role of an IQ estimate on the beneficial effects of strategy instructions. A total of 142 participants (aged 18–85 years) received either intentional learning or strategy (“sentence generation”) instructions during encoding of word pairs. Whereas young adults with a lower IQ benefited from strategy instructions, those with a higher IQ did not, presumably because they already use strategies spontaneously. Older adults showed the opposite effect: following strategy instructions, older adults with a higher IQ showed a strong increase in memory performance (approximately achieving the level of younger adults), whereas older adults with a lower IQ did not, suggesting that they have difficulties implementing the provided strategies. These results highlight the importance of the role of IQ in compensating for the aging-related memory decline.     

Does Controlling for Temporal Parameters Change the Levels-of-Processing Effect in Working Memory?

The distinguishability between working memory (WM) and long-term memory has been a frequent and long-lasting source of debate in the literature. One recent method of identifying the relationship between the two systems has been to consider the influence of long-term memory effects, such as the levels-of-processing (LoP) effect, in WM. However, the few studies that have examined the LoP effect in WM have shown divergent results. This study examined the LoP effect in WM by considering a theoretically meaningful methodological aspect of the LoP span task. Specifically, we fixed the presentation duration of the processing component a priori because such fixed complex span tasks have shown differences when compared to unfixed tasks in terms of recall from WM as well as the latent structure of WM. After establishing a fixed presentation rate from a pilot study, the LoP span task presented memoranda in red or blue font that were immediately followed by two processing words that matched the memoranda in terms of font color or semantic relatedness. On presentation of the processing words, participants made deep or shallow processing decisions for each of the memoranda before a cue to recall them from WM. Participants also completed delayed recall of the memoranda. Results indicated that LoP affected delayed recall, but not immediate recall from WM. These results suggest that fixing temporal parameters of the LoP span task does not moderate the null LoP effect in WM, and further indicate that WM and long-term episodic memory are dissociable on the basis of LoP effects.