A comparison of conscious and automatic memory processes for picture and word stimuli: a process dissociation analysis

Four experiments were conducted to evaluate explanations of picture superiority effects previously found for several tasks. In a process dissociation procedure (Jacoby, 1991) with word stem completion, picture fragment completion, and category production tasks, conscious and automatic memory processes were compared for studied pictures and words with an independent retrieval model and a generate-source model. The predictions of a transfer appropriate processing account of picture superiority were tested and validated in "process pure" latent measures of conscious and unconscious, or automatic and source, memory processes. Results from both model fits verified that pictures had a conceptual (conscious/source) processing advantage over words for all tasks. The effects of perceptual (automatic/word generation) compatibility depended on task type, with pictorial tasks favoring pictures and linguistic tasks favoring words. Results show support for an explanation of the picture superiority effect that involves an interaction of encoding and retrieval processes.     

Measuring automatic retrieval

A variety of procedures have been used to assess automatic retrieval effects on memory, including implicit memory tests and the process dissociation approach. Theoretical concerns with each are summarized prior to describing a procedure for evaluating automatic retrieval that is based on retrieval speed. Specifically, in a speeded implicit task, participants were encouraged to complete word stems using strictly automatic retrieval by presenting several practice test trials that did not allow responding based on previously studied items and by encouraging speed of responding. This speeded implicit task was compared with a condition in which conscious retrieval of studied information was not possible and a condition in which conscious retrieval was required, providing converging evidence to support the hypothesis that the speeded implicit procedure can yield pure estimates of automatic retrieval. Furthermore, evidence from a standard implicit memory task yielded comparable data that suggests that participants engaged automatic retrieval processes on this task also.     

The Role of Decision Processes in Conscious Recollection

Dual-process models of recognition memory posit a rapid retrieval process that produces a general sense of familiarity and a slower retrieval process that produces conscious recollections of prior experience. The remember / know paradigm has been used to study the subjective correlates of these two processes, with remember judgments assumed to index conscious recollection and know judgments assumed to index familiarity. Recently, a two-criterion signal detection model has been proposed as an alternative account of this paradigm. This model assumes only a single memory process with a criterion remember from know responses. This report presents an empirical test of the model's critical prediction that manipulations that influence criterion placement should influence both remember and know judgments. An experiment confirmed this prediction, demonstrating that subjects who were told that 70% of the test items were study items produced more remember and know responses than subjects who were told that 30% of the test items were study items.     

Visual searh through word lists as a function of grade level,reading ability,and target repetition

Second-, fourth-, and sixth-grade students of high or low reading ability and college students carried out a visual-search task in which they scanned a list of 10 words, looking for a target word which was changed every trial or remained constant during an entire session. Search time increased linearly with serial position, consistent with a serial self-terminating model of visual search. The search rate increased from 3.3 words/sec in the second grade to 8.4 words/sec in college. Reading ability was not a significant factor in any comparisons. These results on the development of visual-search ability agree with others in showing that with increasing age there is a marked increase in search speed. However, retarded readers are as competent as their age peers on this task, suggesting that reading dysfunction must be traced to other deficiencies.     

Working memory and counterexample retrieval for causal conditionals

The present study is part of recent attempts to specify the characteristics of the counterexample retrieval process during causal conditional reasoning. The study tried to pinpoint whether the retrieval of stored counterexamples (alternative causes and disabling conditions) for a causal conditional is completely automatic in nature or whether the search process also demands executive working memory (WM) resources. In Experiment 1, participants were presented with a counterexample generation task and a measure of WM capacity. We found a positive relation between search efficiency, as measured by the number of generated counterexamples in limited time, and WM capacity. Experiment 2 examined the effects of a secondary WM load on the retrieval performance. As predicted, burdening WM with an attention-demanding secondary task decreased the retrieval efficiency. Both low and high spans were affected by the WM load but load effects were less pronounced for the most strongly associated counterexamples. Findings established that in addition to an automatic search component, the counterexample retrieval draws on WM resources.     

Divided attention at encoding and retrieval for once- and thrice-presented items: A micro-level analysis of attentional costs

Several recent studies have indicated that retrieval, unlike encoding, is only minimally affected by dividing attention, but is associated with significant secondary task costs. The reported experiment further investigated the effects of divided attention at encoding and retrieval on recall by manipulating the number of presentations of word pairs and using a cued-recall paradigm and a multimeasure approach. This allowed the assessment of accuracy and latency of retrievals of once- and thrice-presented items, as well as of overall attentional costs and the temporal distribution of attentional costs incurred by these retrievals. The results obtained show that providing episodic enhancement to the cue–target relationships, by presenting word pairs three times during the study phase, increases both the probability of retrieval success and the speed of the retrieval. In addition, repetition leads to retrieval which requires less attentional resources. In particular, repeated items require fewer attentional resources during the cue-elaboration/search component. This effect seems to be mediated by a change in the nature of retrievals of the thrice-presented pairs, which seem to mostly bypass the search process, making it faster and less dependent on attentional resources.     

The effect of warnings on false memories in young and older adults

In the present experiments, we examined adult age differences in the ability to suppress false memories, using the Deese-Roediger-McDermott (DRM) paradigm (Deese, 1959; Roediger & McDermott, 1995). Participants studied lists of words (e.g., bed, rest, awake, etc.), each related to a nonpresented critical lure word (e.g., sleep). Typically, recognition tests reveal false alarms to critical lures at rates comparable to those for hits for studied words. In two experiments, separate groups of young and older adults were unwarned about the false memory effect, warned before studying the lists, or warned after study and before test. Lists were presented at either a slow rate (4 sec/word) or a faster rate (2 sec/word). Young adults were better able to discriminate between studied words and critical lures when warned about the DRM effect either before study or after study but before retrieval, and their performance improved with a slower presentation rate. Older adults were able to discriminate between studied words and critical lures when given warnings before study, but not when given warnings after study but before retrieval. Performance on a working memory capacity measure predicted false recognition following study and retrieval warnings. The results suggest that effective use of warnings to reduce false memories is contingent on the quality and type of encoded information, as well as on whether that information is accessed at retrieval. Furthermore, discriminating between similar sources of activation is dependent on working memory capacity, which declines with advancing age.     

Neural enhancement and attenuation induced by repetitive recall

Learning is the process of accumulating information. Repetition can make the process of retrieving information more efficient. The mechanisms by which repetition facilitates the retrieval process, however, are not yet clear. Here, we used event-related functional magnetic resonance imaging to investigate the effects of repetition on cued recall. In this study, participants were asked to encode visually presented semantically unrelated word pairs. The word presented on the left side served as the cue, and the word presented on the right side was the target. In the first test phase, participants were presented with the cue and asked to recall the associated word (target) from the study phase. The second test phase was performed 20 min later using the same method. Participants responded orally during the interval between image acquisitions, and no feedback was provided. Neural activity for identical stimuli and responses across the two tests were compared. As compared with the first test phase, the right dorsolateral prefrontal, bilateral inferior parietal, and precuneus regions showed greater activity and the left inferior frontal areas showed reduced activity during the second test phase. These shifts in neural activity that occurred with repetition may reflect the dynamics of the retrieval process.     

Effects of divided attention on perceptual and conceptual memory tests: An analysis using a process-dissociation approach

In two experiments, the nature of the relation between attention available at learning and subsequent automatic and controlled influences of memory was explored. Participants studied word lists in full and divided encoding conditions. Memory for the word lists was then tested with a perceptually driven task (stem completion) in Experiment 1 and with a conceptually driven task (category association) in Experiment 2. For recall cued with word stems, automatic influences of memory derived using the process-dissociation procedure remained invariant across a manipulation of attention that substantially reduced conscious recollection for the learning episode. In contrast, for recall cued with category names, dividing attention at learning significantly reduced the parameter estimates representing both controlled and automatic memory processes. These findings were similar to those obtained using indirect test instructions. The results suggest that, in contrast to perceptual priming, conceptual priming may be enhanced by semantic processing, and this effect is not an artifact of contamination from conscious retrieval processes.     

Is there a special association between self judgements and conscious recollection?

Dual‐process models of recognition memory posit a rapid retrieval process that produces a general sense of familiarity and a slower retrieval process that produces conscious recollections of prior experience. The Remember–Know paradigm has been used to study the subjective correlates of these two processes with Remember judgements assumed to index conscious recollection and Know judgements assumed to index familiarity. In this paper we examine Conway and Dewhurst's recent finding that judgements of self during encoding produce more Remember responses than alternative semantic judgements. While one might interpret this result to suggest a special association between self judgement and conscious recollection, we consider the possibility that it occurs because of greater discriminability in this condition. The results of four experiments demonstrate that a self judgement condition produces more, fewer, or an equal number of Remember responses relative to a control condition depending on whether overall discriminability in the self judgement condition is greater than, less than, or equal to that in the control condition. The implications of these results for conceptions of self judgement and the use of the Remember–Know paradigm are detailed. Copyright © 1999 John Wiley & Sons, Ltd.     

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。     

Single-trial free recall from temporal search sets in long-term memory

The notion that the primacy effect, which is found in single-trial free-recall experiments, is partly a function of a selective-search component (Shiffrin, 1970) is contingent upon the ability of subjects to retrieve information via a distinctive temporal cue. The beginning of a list may be such a cue which defines a restricted temporal search set within a list as a whole. To test this theory, a second list-half primacy effect was generated in some 26 “unrelated” words lists by associating one color with each word in the first list half and another color with each word in the second list half. As predicted by the two-process theory, retrieval of the words which were presented around the color shift was differentially facilitated as measured by the difference between the probabilities of recall and recognition at each serial position and as compared to that of lists where the color codes were randomly presented.

     

The picture superiority effect in a cross-modality recognition task

Words and pictures were studied, and recognition tests were given in which each studied object was to be recognized in both word and picture format. The main dependent variable was the latency of the recognition decision. The purpose was to investigate the effects of study modality (word or picture), of congruence between study and test modalities, and of priming resulting from repeated testing. Experiments 1 and 2 used the same basic design, but the latter also varied retention interval. Experiment 3 added a manipulation of instructions to name studied objects, and Experiment 4 deviated from the others by presenting both picture and word referring to the same object together for study. The results showed that congruence between study and test modalities consistently facilitated recognition. Furthermore, items studied as pictures were more rapidly recognized than were items studied as words. With repeated testing, the second instance was affected by its predecessor, but the facilitating effect of picture-to-word priming exceeded that of word-to-picture priming. The findings suggest a two-stage recognition process, in which the first is based on perceptual familiarity and the second uses semantic links for a retrieval search. Common-code theories that grant privileged access to the semantic code for pictures or, alternatively, dual-code theories that assume mnemonic superiority for the image code are supported by the findings. Explanations of the picture superiority effect as resulting from dual encoding of pictures are not supported by the data.     

Semantic-memory sources of episodic retrieval failure

In a cued-recall paradigm, retrieval blocking was investigated as a source of episodic retrieval failure. Each unrelated-interference (UR-I) word pair (e.g., “nurse-dollar”) had its own “competitive alternative” (e.g., “doctor’), which not only was strongly related to the cue word, but also possessed the same first two letters and final letter as did the target word. None of the unrelated-control (UR-C) word pairs (e.g., “clock-dollar”) had such an alternative. Cued recall substantially increased from the cue-word-only (e.g., “nurse- ”) to the three-letters-also cue condition (e.g., “nurse-do___r”) for the UR-C but not for the UR-I word pairs. Instead, subjects frequently reported the competitive alternatives in place of the UR-I target words in the three-letters-also cue condition. It was suggested that, relying on the primary plausibility judgment, subjects falsely accepted the competitive alternatives while the UR-I target words were blocked from retrieval by the potent retrieval of these plausible alternatives.     

内隐与外显记忆编码阶段脑机制的重叠与分离

记忆包括编码和提取两个重要阶段, 以往研究多关注内隐和外显记忆在提取阶段的脑机制分离, 那二者在编码阶段的脑机制是否不同？为探讨这个问题, 该实验采用两阶段的迫选再认方式, 把学习项目区分成三类：随后被选择且告知为见过的项目(记住), 随后被选择但告知为猜测的项目 (启动)以及随后未被选择的项目(忘记)。结果表明, 从200 ms开始的颞区负走向Dm效应为内隐记忆(启动vs忘记)所特有, 反映了对刺激的知觉加工过程, 400~500 ms前额区正走向的Dm效应为外显记忆(记住vs忘记)所特有, 反映了对刺激的精细加工过程, 而200~300 ms中央区及600 ms开始的顶区负走向的Dm效应为两种记忆类型所共有, 它们分别反映了对刺激的注意状态以及把编码后的刺激信息登记进相应记忆系统的过程。因此, 内隐记忆与外显记忆在编码阶段的脑机制既存在着分离, 也存在着重叠的现象。     

Retrieval search for category and thematic information in memory by children and adults

Retrieval search for the last target word of four noun category (Bus-Airplane-Car-Train) and thematic (Suitcase-Coat-Ticket-Train) stimuli by children and adults was examined in four experiments. Stimulus classification at acquisition was ensured by orienting questions. Associative search structures were externalized more or less at retrieval by providing cues reinstating the whole (Bus-Airplane-Car) or only part (Bus-Airplane, or Bus) of the associative context, cues with the same or changed (Car-Bus-Airplane) word order, or cues representing the stimulus classification (Vehicle). The results suggest that the associative structures of memory help constrain and mediate retrieval search for stimulus information, and that these structures as well as representations of the stimulus events in memory seem to differ for thematic and category events, and for children and adults, contributing to search differences.     

焦虑情绪对图像信息意识提取和无意识提取影响的实验研究

采用加工分离程序,以不同性价图片为实验材料,考察了特质焦虑、启动焦虑和非焦虑三种焦虑类型对图片信息意识提取和无意识提取的影响,结果表明：（1）不同焦虑类型对图像信息的意识提取和无意识提取均有影响,其中特质焦虑对图像的无意识提取更敏感,非焦虑状态对意识提取更敏感;（2）特质焦虑明显促进了负性图片的意识和无意识提取且干扰了正性图片的提取,启动焦虑促进了对负性图片的意识提取。     

On the speed of intuition: Intuitive judgments of semantic coherence under different response deadlines

Intuition is the ability to judge stimulus properties on the basis of information that is activated in memory but not consciously retrieved. We investigated one central feature of intuitive judgments--namely, their speed. Participants judged whether or not three clue words were coherent in the sense that they were weakly associated with a common fourth concept. To restrict the time available for conscious deliberation of possible solution words, participants had to synchronize their judgments with a response signal appearing at different lags after the clue words. In two experiments, participants discriminated coherent and incoherent triads reliably better than chance, even when they did not consciously retrieve the solution word and the lag between clue words and response signal was as short as 1.5 sec. Results indicate that intuitive judgments can indeed be made very fast and without extended conscious deliberation. Possible mechanisms underlying intuitive judgments are discussed.     

A context noise model of episodic word recognition

Item noise models of recognition assert that interference at retrieval is generated by the words from the study list. Context noise models of recognition assert that interference at retrieval is generated by the contexts in which the test word has appeared. The authors introduce the bind cue decide model of episodic memory, a Bayesian context noise model, and demonstrate how it can account for data from the item noise and dual-processing approaches to recognition memory. From the item noise perspective, list strength and list length effects, the mirror effect for word frequency and concreteness, and the effects of the similarity of other words in a list are considered. From the dual-processing perspective, process dissociation data on the effects of length, temporal separation of lists, strength, and diagnosticity of context are examined. The authors conclude that the context noise approach to recognition is a viable alternative to existing approaches.     

Use of the mutual exclusivity assumption by young word learners

A critical question about early word learning is whether word learning constraints such as mutual exclusivity exist and foster early language acquisition. It is well established that children will map a novel label to a novel rather than a familiar object. Evidence for the role of mutual exclusivity in such indirect word learning has been questioned because: (1) it comes mostly from 2 and 3-year-olds and (2) the findings might be accounted for, not by children avoiding second labels, but by the novel object which creates a lexical gap children are motivated to fill. Three studies addressed these concerns by having only a familiar object visible. Fifteen to seventeen and 18-20-month-olds were selected to straddle the vocabulary spurt. In Study 1, babies saw a familiar object and an opaque bucket as a location to search. Study 2 handed babies the familiar object to play with. Study 3 eliminated an obvious location to search. On the whole, babies at both ages resisted second labels for objects and, with some qualifications, tended to search for a better referent for the novel label. Thus mutual exclusivity is in place before the onset of the naming explosion. The findings demonstrate that lexical constraints enable babies to learn words even under non-optimal conditions--when speakers are not clear and referents are not visible. The results are discussed in relation to an alternative social-pragmatic account.