Context change and retrieval difficulty in the list-before-last paradigm

Using the "list-before-last" paradigm (Jang & Huber, Journal of Experimental Psychology: Learning, Memory, and Cognition, 34, 112-127, 2008; Shiffrin, Science, 168, 1601-1603, 1970), we examined whether the difficulty involved in retrieving a previously studied list affects the recall of the current list. Participants studied three lists (L1, L2, and L3), and between L2 and L3 study they either engaged in retrieval of L1 or solved math problems for the same duration of time. After L3 encoding, all participants recalled L2. We examined accurate recall of L2, intrusions from L3, and also the first-response function from L2 across all four experiments. In Experiments 1 and 2, retrieval difficulty was manipulated by presenting participants with variable numbers of letter cues for the L1 words, with some participants receiving more cues than others. In Experiment 1, L1 and L2 words shared the first two letters in common to create potential item interference, whereas in Experiment 2, they did not share common cues. In Experiments 3 and 4, we manipulated retrieval difficulty using a delay manipulation-L1 was encoded 1, 24, or 72?h prior to the session during which L2 and L3 were encoded. In Experiment 3, L1 retrieval involved a cued recall test, whereas in Experiment 4, it involved a free recall test. The results of all of these experiments showed that, as compared to solving math problems, retrieving L1 led to forgetting of L2, reduced intrusions from L3, and reduced first-response functions from L2. However, all of the dependent measures were invariant across the various manipulations of retrieval difficulty. We discuss the results in terms of the context-change interpretation of prior-list retrieval.     

Encoding distinctiveness and the encoding shift penalty in children and adults

This study determined some of the reasons for developmental differences in retrieval variability. The critical manipulation involved the use of semantic orienting questions at both acquisition and retrieval for elementary school children (7 and 10 years of age) and adults. The retrieval questions biased the sampling of cue information compatible or incompatible with the information sampled in acquisition. The recall difference that resulted is the Encoding Shift Penalty. Experiment 1 manipulated encoding distinctiveness at acquisition and the delay between acquisition and retrieval. Experiment 2 varied acquisition encoding constraint and employed two retrieval trials varying the kind of retrieval question. Among other findings, the results suggest that (1) the acquisition encoding of adults is more distinctive than is that of children; (2) encoding distinctiveness affects the probability of sampling and resampling compatible cue information, and the identification of target event information once cue comptibility is ensured at retrieval; and (3) incompatible initial samples of retrieval cue information for children may interfere with their ability to resample successfully.     

Mood and the generation effect

Three experiments address the assumptions, derived from a dual-force model, that positive mood supports assimilative (knowledge-driven) processes whereas negative mood supports accommodative (stimulus-driven) functions, and that mood-selective recall (mood congruency) is mainly a matter of assimilation. The generation-effect paradigm was borrowed from memory research to test these assumptions. In Experiment 1, the theoretical variable, degree of assimilation, was operationalised by the ease with which stimulus meaning could be generated from word fragments. In Experiment 2, self-generated stimuli (assimilation) were compared to experimenter-provided stimuli (accommodation). As predicted, positive mood supported assimilation which in turn enhanced mood-congruent recall. In Experiment 3, retrieval mood rather than encoding mood was manipulated. In this situation, positive mood facilitated the recall of all self-generated information, whether congruent or not. The empirical results are generally consistent with the predictions derived from the dual-force framework.     

Validating running memory span: Measurement of working memory capacity and links with fluid intelligence

We manipulated running memory span tasks to examine effects on recall and relations with criterion measures of working memory capacity and general fluid intelligence. The goal of the manipulations was to limit or enhance opportunities for active input processing and response preparation in advance of test. We manipulated presentation rate in Experiment 1. Recall was higher at slow than at fast rates, but correlations with criterion measures were much the same across rate conditions. In Experiment 2, we manipulated the time at which the number of items to report was made known to the participants. They were given that information in advance (precue) or at test (postcue). Recall scores and correlations with criterion measures were much the same across cuing conditions. We conclude that running memory span provides valid measurement of working memory capacity that is predictive of higher order cognition across a wide range of conditions.     

Working memory load differentially affects tip-of-the-tongue states and feeling-of-knowing judgments

Tip-of-the-tongue states (TOTs) are judgments of the likelihood of imminent retrieval for items currently not recalled, whereas feeling-of-knowing judgments (FOKs) are predictions of successful recognition for items not recalled. The assumption has been that similar metacognitive processes dictate these similar judgments. In Experiment 1, TOTs and FOKs were compared for general information questions. Participants remembered four digits (working memory load) during target retrieval for half of the questions, and there was no memory load for the other questions. Working memory did not affect recall but decreased the number of TOTs and increased FOKs. In Experiment 2, participants maintained six digits during retrieval. TOTs decreased in the working memory condition, but FOKs remained constant. Experiment 3 replicated the results of Experiment 2 while asking for FOKs for recall. In each of the first three experiments, positive metacognitive judgments also affected working memory performance, supporting the idea that working memory and metamemory use similar monitoring processes. In Experiment 4, visual working memory did not affect TOTs or FOKs. The data support a view that TOTs and FOKs are separable metacognitive entities.     

The effects of cue distinctiveness on odor-based context-dependent memory

The distinctiveness of an ambient odor was examined in relation to its success as a cue in contextdependent memory. Distinctiveness was examined in terms of both cue novelty and contextual appropriateness. Two experiments were conducted in which three different ambient odors that varied in familiarity and contextual appropriateness were manipulated at an incidental word learning encoding session and at a free recall retrieval session 48 h later. Experiment 1 revealed that when a novel ambient odor (osmanthus) was the available context cue, word recall was better than in any other condition. Further, among familiar odor cues, recall was better with a contextually inappropriate odor (peppermint) than with a contextually appropriate odor (clean fresh pine). Experiment 2 confirmed that superior word recall with osmanthus and peppermint depended on the odor cue’s being available at both encoding and retrieval, and that the relation of an odor to the situational context is a key factor for predicting its effectiveness as a retrieval cue.     

The role of semantic knowledge in retrieval from episodic long-term memories: Implications for a model of retrieval

Two experiments were conducted, using a paired-associate recall reaction time paradigm, to assess the role semantic knowledge plays in retrieval of long-term episodic memories. In Experiment I, word frequency and meaningfulness were manipulated; high-frequency stimuli led to significantly longer reaction times, while meaningfulness had no significant effect. In Experiment II, the role of the distribution of preexperimental associates of the stimulus was further investigated by comparing retrieval time when the stimulus had either a high- or low-strength primary associate; the former resulted in longer reaction times. The implications of these results for a model of retrieval were discussed. Exhaustive search models were found inadequate, but viable parallel and serial self-terminating models were developed. In both of these models, retrieval time is a function of strength of the correct associate, relative to total strength of a restricted set of semantic associates of the stimulus.     

Evidence for disproportionate dual-task costs in older adults for episodic but not semantic memory

Previous research demonstrates that older adults are poor at dual tasking, but there is less agreement on whether their decrement is worse than that predicted from single-task performance. This study investigated whether task domain moderates dual-task costs in old age. In two experiments, young and older adults retrieved either previously learned associates (episodic retrieval) or overlearned category members (semantic retrieval) under single or working-memory load conditions, using cued recall (Experiment 1) and recognition (Experiment 2) procedures. In both experiments the proportional costs of dual tasking were age invariant for semantic retrieval but were particularly marked for episodic retrieval, although the size of the age effect was reduced in recognition compared to cued recall. The data suggest that age effects in dual tasking may be domain specific.     

Availability and category-frequency estimation

Individuals judged how often examples of taxonomic categories had occurred in a study list. An availability hypothesis was tested--that frequency estimates are based on the retrieval of instances. Cued (by category names) recall of the examples served as an index of availability. The hypothesis was confirmed--there were strong positive correlations between frequency judgments and recall (with the influence of actual frequency removed)--given one or more of the following conditions: List instances were not categorized aloud as they were presented; frequency estimation was preceded by cued recall; frequency estimation was delayed by a week. Limitations on availability occurred under other conditions--notably, when individuals, during list presentation, named the categories to which items belonged and received feedback about their categorizations. Under these circumstances, correlations of frequency estimation and recall were often not significantly different from zero, and frequency judgments and recall sometimes reacted differently to changes in independent variables (e.g., frequency judgments of young and elderly subjects did not differ reliably, even though cued recall of young persons markedly exceeded that of elderly subjects).     

Retrieval of Episodic Information From Memory: Comparisons Among 3- and 4-Year-Olds, 7- and 8-Year-Olds,and Adults

Young children's and adults' recall of episodic information was explored in 4 experiments. The task required participants to recall a target noun presented as the last item of a 4-noun string of related (either categorically or thematically) or unrelated words. Providing all 3 preceding nouns or a subset of them cued recall. Experiment 1 found that 7- and 8-year-old children's recall was better with pictures as opposed to text, and children showed performance equal to adults with thematically related pictorial stimuli. Using pictorial stimuli, Experiment 2 showed that the number of cues present at retrieval affected 7- and 8-year-olds' recall. Experiments 3 and 4 tested recall of episodic information in 3- and 4-year-olds using pictorial stimuli. The results suggested that young children also have access to episodic information in memory and the number of cues present at retrieval influenced recall. The findings are discussed in the context of children's memory for events.     

The retrieval practice effect in associative recognition

Recalling an item interferes with recall of related memories. Evidence is presented that retrieval interference occurs in associative recognition as well as recall. In Experiment 1, subjects studied pairs of category exemplars. Retrieval practice followed, during which some pairs appeared in a cued recall test. A final test of associative recognition (with remember-know judgments) found lower accuracy and hit rate for nonpracticed pairs belonging to retrieval-practiced categories. In Experiment 2, subjects studied noun pairs from overlapping sets, with study duration manipulated between subjects. Retrieval practice was manipulated by presenting some members of a set in a previous block during the recognition test. With long study duration, retrieval interference was evident in both recognition and remember judgments. With short study duration, it appeared only in remember judgments. These results support a dual-process account in which retrieval interference is specific to recollection and becomes evident in recognition performance only when recollection is sufficiently dominant.     

Order information and retrieval distinctiveness: recall of common versus bizarre material

The order-encoding hypothesis (E. L. DeLosh & M. A. McDaniel, 1996) assumes that serial-order information contributes to the retrieval of list items and that serial-order encoding is better for common items than bizarre items. In line with this account, Experiment 1 revealed better free recall and serial-order memory for common than for bizarre items in pure lists, and Experiment 2 showed that recall for bizarre items increased and the recall advantage of common items was eliminated when serial-order encoding for bizarre items was increased to the level of common items. However, inconsistent with a second assumption that bizarre-item advantages in mixed lists reflect better individual-item encoding for bizarre items, Experiments 3 and 4 showed that the bizarreness effect in mixed lists is eliminated when alternative retrieval strategies are encouraged. This set of findings is better explained by the differential-retrieval-process framework, which proposes that contextual factors (e.g., list composition) influence the extent to which various types of information are used at retrieval, with the bizarreness advantage in mixed lists dependent on a distinctiveness-based retrieval process.     

Recall order determines the magnitude of directed forgetting in the within-participants list method

In three experiments, we investigated the effect of recall order on directed forgetting when the within-participants list method is used. Experiment 1 showed that participants tend to recall to-be-remembered (R) items before to-be-forgotten (F) items when they can recall items in any order. In Experiment 2, recall order was manipulated (F-R or R-F). The results showed that only the R-F order led to directed forgetting. Finally, in Experiment 3, recall order was also manipulated, and half of the participants were explicitly instructed to use a relational strategy when both F and R items were presented. Again, only the R-F order led to directed forgetting. These results demonstrate that directed forgetting under the list method hinges on the output order in which participants recall the F and R information. Thus, output order should be taken into account by researchers investigating specific mechanisms that lead to directed forgetting.     

The impact of stereotype-incongruent information on perceived group variability and stereotype change

Three experiments showed increases in the perceived variability of social groups after perceivers received stereotype-incongruent information about group members. In Experiment 1, participants generated flatter distributions after exposure to incongruent information, compared with equally deviant congruent information, in the form of typical verbal materials. Experiment 2 indicated similar changes in dispersion after the presentation of numeric information about a single group member. In Experiment 3, the authors manipulated cognitive load at encoding or at the time group judgments were requested. Under conditions of cognitive constraint, stereotype-incongruent information ceased to promote more dispersed group representations. These results are consistent with the idea that incongruent information triggers more deliberative and comprehensive retrieval and generation of exemplars. The authors discuss the implications of these findings for stereotype change.     

The Effects of Vocalisation on Situational Frequency Estimation

Two experiments are reported that studied the effects of vocalisation on situational frequency judgment. Subjects saw lists of words and were later asked to judge frequency of occurrence on the list. In Experiment 1, the word list was learned incidentally, and frequency estimates were higher for words that subjects had read aloud during study than for those that had been read silently. In Experiment 2, an intentional-learning procedure was used; higher estimates for words read aloud than for those read silently were found when pronunciation was manipulated within subjects but not when it was manipulated between subjects. In all cases, pronunciation had no effect on estimates for words that had only been presented once on the study list. These results suggest that multiple processes may underlie frequency estimation.     

Remembering computer command names: Effects of subject generation versus experimenter imposition

Two experiments analyzed the effectiveness of goal statements in aiding recall of self-generated as opposed to experimenter-imposed command names. Subjects were presented with a series of before-after pairs representing the computer states before and after a command was executed. In Experiment 1, during study, one group of subjects generated a command name in response to each pair; a second group generated a goal statement describing the goal to be accomplished in addition to generating a command name. During recall, half of each group was required to recall the name, whereas the other half was required to describe the goal before attempting to recall the name. In Experiment 2, during study, command names (and goals for those subjects in the goal condition) were imposed by the experimenter rather than generated by the subject. Subjects who generated goals and names recalled more command names than did those who generated only names or who received imposed goals and/or names. Generation of an appropriate goal at study improved encoding by helping subjects to select more appropriate command names; generation of an appropriate goal at test improved retrieval for appropriate names only, presumably by activating a relevant subset of names. Even in the relatively simple task of naming and remembering command names, having an appropriate model of the domain through the use of specific goal statements substantially improved performance.     

The effects of bilingual language proficiency on recall accuracy and semantic clustering in free recall output: evidence for shared semantic associations across languages

Two experiments investigated how well bilinguals utilise long-standing semantic associations to encode and retrieve semantic clusters in verbal episodic memory. In Experiment 1, Spanish-English bilinguals (N?=?128) studied and recalled word and picture sets. Word recall was equivalent in L1 and L2, picture recall was better in L1 than in L2, and the picture superiority effect was stronger in L1 than in L2. Semantic clustering in word and picture recall was equivalent in L1 and L2. In Experiment 2, Spanish-English bilinguals (N?=?128) and English-speaking monolinguals (N?=?128) studied and recalled word sequences that contained semantically related pairs. Data were analyzed using a multinomial processing tree approach, the pair-clustering model. Cluster formation was more likely for semantically organised than for randomly ordered word sequences. Probabilities of cluster formation, cluster retrieval, and retrieval of unclustered items did not differ across languages or language groups. Language proficiency has little if any impact on the utilisation of long-standing semantic associations, which are language-general.     

Explicit awareness supports conditional visual search in the retrieval guidance paradigm

In four experiments we explored whether participants would be able to use probabilistic prompts to simplify perceptually demanding visual search in a task we call the retrieval guidance paradigm. On each trial a memory prompt appeared prior to (and during) the search task and the diagnosticity of the prompt(s) was manipulated to provide complete, partial, or non-diagnostic information regarding the target's color on each trial (Experiments 1–3). In Experiment 1 we found that the more diagnostic prompts was associated with faster visual search performance. However, similar visual search behavior was observed in Experiment 2 when the diagnosticity of the prompts was eliminated, suggesting that participants in Experiment 1 were merely relying on base rate information to guide search and were not utilizing the prompts. In Experiment 3 participants were informed of the relationship between the prompts and the color of the target and this was associated with faster search performance relative to Experiment 1, suggesting that the participants were using the prompts to guide search. Additionally, in Experiment 3 a knowledge test was implemented and performance in this task was associated with qualitative differences in search behavior such that participants that were able to name the color(s) most associated with the prompts were faster to find the target than participants who were unable to do so. However, in Experiments 1–3 diagnosticity of the memory prompt was manipulated via base rate information, making it possible that participants were merely relying on base rate information to inform search in Experiment 3. In Experiment 4 we manipulated diagnosticity of the prompts without manipulating base rate information and found a similar pattern of results as Experiment 3. Together, the results emphasize the importance of base rate and diagnosticity information in visual search behavior. In the General discussion section we explore how a recent computational model of hypothesis generation (HyGene; Thomas, Dougherty, Sprenger, & Harbison, 2008), linking attention with long-term and working memory, accounts for the present results and provides a useful framework of cued recall visual search.     

成员关系对协作提取成绩的影响

当人们与搭档组成社会群体一起协作讨论某些已经发生的事件或经验时, 该社会群体中的成员关系对协作提取成绩的影响仍不明确。本研究通过两项实验, 分别使用语词词单和情景故事作为实验材料, 考察成员关系(包括关系类型和关系时长)对协作提取成绩的影响。研究结果表明, 当记忆的材料为语词词单时, 青年陌生组出现了协作抑制; 而当记忆的材料为情景故事时, 青年夫妻和老年夫妻组均出现了协作促进。此外, 老年夫妻在协作提取情景故事的过程中使用的有效交流策略更多, 且这些有效交流策略的使用与更高的协作提取成绩有关。该结果支持了具有长时亲密关系的老年夫妻之间的“交互记忆系统”对协作促进的关键作用, 为理解成员关系对协作提取成绩的影响提供了全面的证据。     

The relation between item identification difficulty and elaborative conceptual processing for children and adults

The four experiments concerned the relation between the difficulty of item identification processes, elaborative conceptual processing, and developmental differences in cued recall. Elaborative conceptual processing was manipulated by asking related ("How many are related?"), category ("How many are vehicles?"), and analytic ("How many usually carry freight?") orienting questions about four-word stimuli in which the words were categorically related (Bus-Airplane-Car-Train). The measures of elaborative processing were the speed and accuracy of question answers. Cued recall for the targets (Train) was assessed for one-word (Bus) or two-word (Bus-Airplane) cues, which were varied to determine if elaborative processing affected cue discriminability or constructability, or both. The difficulty of item identification was varied in several ways. In Experiment 1, the graphemic information was degraded in the acquisition stimuli, or the retrieval cues, or the stimulus words were intact. In Experiments 2 and 3, acquisition presentation time was varied and the stimuli were read by the experimenter or the subject. Experiment 4 featured pictures to determine generalizability. The results showed that elaborative conceptual processing facilitates recall. Most important, item identification processes limit elaborative conceptual processing for both words and pictures, and more for children than for college students.