Showing papers in "Journal of Experimental Psychology: Learning, Memory and Cognition in 2011"

Semantic information activated during retrieval contributes to later retention: Support for the mediator effectiveness hypothesis of the testing effect.

Abstract: Previous research has proposed that tests enhance retention more than do restudy opportunities because they promote the effectiveness of mediating information--that is, a word or concept that links a cue to a target (Pyc & Rawson, 2010). Although testing has been shown to promote retention of mediating information that participants were asked to generate, it is unknown what type of mediators are spontaneously activated during testing and how these contribute to later retention. In the current study, participants learned cue-target pairs through testing (e.g., Mother: _____) or restudying (e.g., Mother: Child) and were later tested on these items in addition to a never-before-presented item that was strongly associated with the cue (e.g., Father)--that is, the semantic mediator. Compared with participants who learned the items through restudying, those who learned the items through testing exhibited higher false alarm rates to semantic mediators on a final recognition test (Experiment 1) and were also more likely to recall the correct target from the semantic mediator on a final cued recall test (Experiment 2). These results support the mediator effectiveness hypothesis and demonstrate that semantically related information may be 1 type of natural mediator that is activated during testing.

Seeing a phrase “time and again” matters: the role of phrasal frequency in the processing of multiword sequences

Abstract: Are speakers sensitive to the frequency with which phrases occur in language? The authors report an eye-tracking study that investigates this by examining the processing of multiword sequences that differ in phrasal frequency by native and proficient nonnative English speakers. Participants read sentences containing 3-word binomial phrases (bride and groom) and their reversed forms (groom and bride), which are identical in syntax and meaning but that differ in phrasal frequency. Mixed-effects modeling revealed that native speakers and nonnative speakers, across a range of proficiencies, are sensitive to the frequency with which phrases occur in English. Results also indicate that native speakers and higher proficiency nonnatives are sensitive to whether a phrase occurs in a particular configuration (binomial vs. reversed) in English, highlighting the contribution of entrenchment of a particular phrase in memory.

Spaced retrieval: absolute spacing enhances learning regardless of relative spacing.

Abstract: Repeated retrieval enhances long-term retention, and spaced repetition also enhances retention. A question with practical and theoretical significance is whether there are particular schedules of spaced retrieval (e.g., gradually expanding the interval between tests) that produce the best learning. In the present experiment, subjects studied and were tested on items until they could recall each one. They then practiced recalling the items on 3 repeated tests that were distributed according to one of several spacing schedules. Increasing the absolute (total) spacing of repeated tests produced large effects on long-term retention: Repeated retrieval with long intervals between each test produced a 200% improvement in long-term retention relative to repeated retrieval with no spacing between tests. However, there was no evidence that a particular relative spacing schedule (expanding, equal, or contracting) was inherently superior to another. Although expanding schedules afforded a pattern of increasing retrieval difficulty across repeated tests, this did not translate into gains in long-term retention. Repeated spaced retrieval had powerful effects on retention, but the relative schedule of repeated tests had no discernible impact.

Neurobiological and memory models of risky decision making in adolescents versus young adults.

Abstract: Predictions of fuzzy-trace theory and neurobiological approaches are examined regarding risk taking in a classic decision-making task-the framing task-as well as in the context of real-life risk taking. We report the 1st study of framing effects in adolescents versus adults, varying risk and reward, and relate choices to individual differences, sexual behavior, and behavioral intentions. As predicted by fuzzy-trace theory, adolescents modulated risk taking according to risk and reward. Adults showed standard framing, reflecting greater emphasis on gist-based (qualitative) reasoning, but adolescents displayed reverse framing when potential gains for risk taking were high, reflecting greater emphasis on verbatim-based (quantitative) reasoning. Reverse framing signals a different way of thinking compared with standard framing (reverse framing also differs from simply choosing the risky option). Measures of verbatim- and gist-based reasoning about risk, sensation seeking, behavioral activation, and inhibition were used to extract dimensions of risk proneness: Sensation seeking increased and then decreased, whereas inhibition increased from early adolescence to young adulthood, predicted by neurobiological theories. Two additional dimensions, verbatim- and gist-based reasoning about risk, loaded separately and predicted unique variance in risk taking. Importantly, framing responses predicted real-life risk taking. Reasoning was the most consistent predictor of real-life risk taking: (a) Intentions to have sex, sexual behavior, and number of partners decreased when gist-based reasoning was triggered by retrieval cues in questions about perceived risk, whereas (b) intentions to have sex and number of partners increased when verbatim-based reasoning was triggered by different retrieval cues in questions about perceived risk. (PsycINFO Database Record (c) 2011 APA, all rights reserved). Language: en

When does testing enhance retention? A distribution-based interpretation of retrieval as a memory modifier.

Abstract: Tests, as learning events, can enhance subsequent recall more than do additional study opportunities, even without feedback. Such advantages of testing tend to appear, however, only at long retention intervals and/or when criterion tests stress recall, rather than recognition, processes. We propose that the interaction of the benefits of testing versus restudying with final-test delay and format reflects not only that successful retrievals are more powerful learning events than are re-presentations but also that the distribution of memory strengths across items is shifted differentially by testing and restudying. The benefits of initial testing over restudying, in this view, should increase as the delay or format of the final test makes that test more difficult. Final-test difficulty, not the similarity of initial-test and final-test conditions, should determine the benefits of testing. In Experiments 1 and 2 we indeed found that initial cued-recall testing enhanced subsequent recall more than did restudying when the final test was a difficult (free-recall) test but not when it was an easier (cued-recall) test that matched the initial test. The results of Experiment 3 supported a new prediction of the distribution framework: namely, that the final cued-recall test that did not show a benefit of testing in Experiment 1 should show such a benefit when that test was made more difficult by introducing retroactive interference. Overall, our results suggest that the differential consequences of initial testing versus restudying reflect, in part, differences in how items distributions are shifted by testing and studying.

Retrieval during learning facilitates subsequent memory encoding.

Abstract: In multiple-list learning, retrieval during learning has been suggested to improve recall of the single lists by enhancing list discrimination and, at test, reducing interference. Using electrophysiological, oscillatory measures of brain activity, we examined to what extent retrieval during learning facilitates list encoding. Subjects studied five lists of items in anticipation of a final cumulative recall test and did either a retrieval or a noretrieval task between study of the lists. Retrieval was from episodic memory (recall of the previous list), semantic memory (generation of exemplars from an unrelated category), or short-term memory (2-back task). Behaviorally, all three forms of retrieval enhanced recall of both previously and subsequently studied lists. Physiologically, the results showed an increase of alpha power (8-14 Hz) from List-1 to List-5 encoding when no retrieval activities were interpolated, but no such increase when any of the three retrieval activities occurred. Brain-behavior correlations showed that alpha-power dynamics from List-1 to List-5 encoding predicted subsequent recall performance. The results suggest that, without intermittent retrieval, encoding becomes ineffective across lists. In contrast, with intermittent retrieval, there is a reset of the encoding process for each single list that makes encoding of later lists as effective as encoding of early lists.

Unskilled but aware: reinterpreting overconfidence in low-performing students.

Abstract: People are generally overconfident in their self-assessments and this overconfidence effect is greatest for people of poorer abilities. For example, poor students predict that they will perform much better on exams than they do. One explanation for this result is that poor performers in general are doubly cursed: They lack knowledge of the material, and they lack awareness of the knowledge that they do and do not possess. The current studies examined whether poor performers in the classroom are truly unaware of their deficits by examining the relationship between students' exam predictions and their confidence in these predictions. Relative to high-performing students, the poorer students showed a greater overconfidence effect (i.e., their predictions were greater than their performance), but they also reported lower confidence in these predictions. Together, these results suggest that poor students are indeed unskilled but that they may have some awareness of their lack of metacognitive knowledge.

Balancing cognitive demands: control adjustments in the stop-signal paradigm.

Abstract: Cognitive control enables flexible interaction with a dynamic environment. In 2 experiments, the authors investigated control adjustments in the stop-signal paradigm, a procedure that requires balancing speed (going) and caution (stopping) in a dual-task environment. Focusing on the slowing of go reaction times after stop signals, the authors tested 5 competing hypotheses for post-stop-signal adjustments: goal priority, error detection, conflict monitoring, surprise, and memory. Reaction times increased after both successful and failed inhibition, consistent with the goal priority hypothesis and inconsistent with the error detection and conflict hypotheses. Post-stop-signal slowing was greater if the go task stimulus repeated on consecutive trials, suggesting a contribution of memory. We also found evidence for slowing based on more than the immediately preceding stop signal. Post-stop-signal slowing was greater when stop signals occurred more frequently (Experiment 1), inconsistent with the surprise hypothesis, and when inhibition failed more frequently (Experiment 2). This suggests that more global manipulations encompassing many trials affect post-stop-signal adjustments.

Bilingual Lexical Access during L1 Sentence Reading: The Effects of L2 Knowledge, Semantic Constraint, and L1-L2 Intermixing.

Abstract: Libben and Titone (2009) recently observed that cognate facilitation and interlingual homograph interference were attenuated by increased semantic constraint during bilingual second language (L2) reading, using eye movement measures. We now investigate whether cross-language activation also occurs during first language (L1) reading as a function of age of L2 acquisition and task demands (i.e., inclusion of L2 sentences). In Experiment 1, participants read high and low constraint English (L1) sentences containing interlingual homographs, cognates, or control words. In Experiment 2, we included French (L2) filler sentences to increase salience of the L2 during L1 reading. The results suggest that bilinguals reading in their L1 show nonselective activation to the extent that they acquired their L2 early in life. Similar to our previous work on L2 reading, high contextual constraint attenuated cross-language activation for cognates. The inclusion of French filler items promoted greater cross-language activation, especially for late stage reading measures. Thus, L1 bilingual reading is modulated by L2 knowledge, semantic constraint, and task demands.

Event-based plausibility immediately influences on-line language comprehension.

Abstract: In some theories of sentence comprehension, linguistically relevant lexical knowledge, such as selectional restrictions, is privileged in terms of the time-course of its access and influence. We examined whether event knowledge computed by combining multiple concepts can rapidly influence language understanding even in the absence of selectional restriction violations. Specifically, we investigated whether instruments can combine with actions to influence comprehension of ensuing patients of (as in Rayner, Warren, Juhuasz, & Liversedge, 2004; Warren & McConnell, 2007). Instrument-verb-patient triplets were created in a norming study designed to tap directly into event knowledge. In self-paced reading (Experiment 1), participants were faster to read patient nouns, such as hair, when they were typical of the instrument-action pair (Donna used the shampoo to wash vs. the hose to wash). Experiment 2 showed that these results were not due to direct instrument-patient relations. Experiment 3 replicated Experiment 1 using eyetracking, with effects of event typicality observed in first fixation and gaze durations on the patient noun. This research demonstrates that conceptual event-based expectations are computed and used rapidly and dynamically during on-line language comprehension. We discuss relationships among plausibility and predictability, as well as their implications. We conclude that selectional restrictions may be best considered as event-based conceptual knowledge rather than lexical-grammatical knowledge.

Working memory capacity and go/no-go task performance: Selective effects of updating, maintenance, and inhibition.

Abstract: The ability to temporarily maintain information in order to successfully perform a task is important in many daily activities However, the ability to quickly and accurately update existing mental representations in distracting situations is also imperative in many of these same circumstances In the current studies, individuals varying in working memory capacity (WMC) performed different varieties of go/no-go tasks that have been hypothesized to measure inhibitory ability The results indicated that low-WMC individuals relative to high-WMC individuals showed worse performance specifically in certain conditions of the conditional go/no-go task Further analyses showed that increasing the temporal lag/number of intervening items between the previous target and the current lure had a deleterious effect on the performance of the low-WMC group only The results indicate a relationship between WMC and the ability to selectively update, maintain, and retrieve information, especially in interference-rich conditions

The Interactive Effects of Listwide Control, Item-Based Control, and Working Memory Capacity on Stroop Performance

Abstract: Hypothesized top-down and bottom-up mechanisms of control within conflict-rich environments were examined by presenting participants with a Stroop task in which specific words were usually presented in either congruent or incongruent colors. Incongruent colors were either frequently (high contingency) or infrequently (low contingency) paired with the word. These items were embedded within lists consisting of either 100% congruent or 100% incongruent filler items to create mostly congruent or mostly incongruent lists. Results indicated a significant item-specific congruency effect, which was largest for high contingency responses and within mostly congruent lists. In addition, a significant listwide congruency effect was obtained, and this interacted with working memory capacity (WMC). There were larger listwide congruency effects for low WMC individuals. Finally, the pattern of Stroop interference across lists for low WMC individuals was dependent upon the congruency of the preceding trial. These results support multiple forms of cognitive control, as well as contingency learning, as mechanisms underlying proportion congruence effects in Stroop and other conflict tasks. These findings are interpreted within Braver, Gray, and Burgess's (2007) dual mechanisms of control theory.

Individual differences in working memory capacity predict retrieval-induced forgetting.

Abstract: Selectively retrieving a subset of previously studied information enhances memory for the retrieved information but causes forgetting of related, nonretrieved information. Such retrieval-induced forgetting (RIF) has often been attributed to inhibitory executive-control processes that supposedly suppress the nonretrieved items' memory representation. Here, we examined the role of working memory capacity (WMC) in young adults' RIF. WMC was assessed by means of the operation span task. Results revealed a positive relationship between WMC and RIF, with high-WMC individuals showing more RIF than low-WMC individuals. In contrast, individuals showed enhanced memory for retrieved information regardless of WMC. The results are consistent with previous individual-differences work that suggests a close link between WMC and inhibitory efficiency. In particular, the finding supports the inhibitory executive-control account of RIF.

Knowledge of a second language influences auditory word recognition in the native language.

Abstract: Many studies in bilingual visual word recognition have demonstrated that lexical access is not language selective. However, research on bilingual word recognition in the auditory modality has been scarce, and it has yielded mixed results with regard to the degree of this language nonselectivity. In the present study, we investigated whether listening to a second language (L2) is influenced by knowledge of the native language (L1) and, more important, whether listening to the L1 is also influenced by knowledge of an L2. Additionally, we investigated whether the listener's selectivity of lexical access is influenced by the speaker's L1 (and thus his or her accent). With this aim, Dutch-English bilinguals completed an English (Experiment 1) and a Dutch (Experiment 3) auditory lexical decision task. As a control, the English auditory lexical decision task was also completed by English monolinguals (Experiment 2). Targets were pronounced by a native Dutch speaker with English as the L2 (Experiments 1A, 2A, and 3A) or by a native English speaker with Dutch as the L2 (Experiments 1B, 2B, and 3B). In all experiments, Dutch-English bilinguals recognized interlingual homophones (e.g., lief [sweet]-leaf /li:f/) significantly slower than matched control words, whereas the English monolinguals showed no effect. These results indicate that (a) lexical access in bilingual auditory word recognition is not language selective in L2, nor in L1, and (b) language-specific subphonological cues do not annul cross-lingual interactions.

On the plasticity of the survival processing effect.

Abstract: Nairne, Thompson, and Pandeirada (2007) discovered a strong and rather general memory advantage for word material processed in a survival-related context. One possible explanation of this effect conceives survival processing as a special form of encoding: Nature specifically “tuned” our memory systems to process and remember fitness-relevant information. We tested this explanation by studying whether the survival processing effect is robust against encoding manipulations that do not affect the fitness relevance of information. Three experiments replicated a strong survival processing effect under standard conditions but showed that the mnemonic benefit of survival processing diminishes or even vanishes when participants focus on a single problem (Experiments 1 and 2) or technique (Experiment 3) of survival. We argue that it is not survival processing per se that facilitates recall but the richness and distinctiveness with which information is encoded.

Order or disorder? Impaired Hebb learning in dyslexia.

Abstract: The present study offers an integrative account proposing that dyslexia and its various associated cognitive impairments reflect an underlying deficit in the long-term learning of serial-order information, here operationalized as Hebb repetition learning. In nondyslexic individuals, improved immediate serial recall is typically observed when one particular sequence of items is repeated across an experimental session, a phenomenon known as the Hebb repetition effect. Starting from the critical observation that individuals with dyslexia seem to be selectively impaired in cognitive tasks that involve processing of serial order, the present study is the first to test and confirm the hypothesis that the Hebb repetition effect is affected in dyslexia, even for nonverbal modalities. We present a theoretical framework in which the Hebb repetition effect is assumed to be a laboratory analogue of naturalistic word learning, on the basis of which we argue that dyslexia is characterized by an impairment of serial-order learning that affects language learning and processing.

Making sense of surprise: an investigation of the factors influencing surprise judgments.

Abstract: Surprise is often defined in terms of disconfirmed expectations, whereby the surprisingness of an event is thought to be dependent on the degree to which it contrasts with a more likely, or expected, outcome. The authors investigated the alternative hypothesis that surprise is more accurately modeled as a manifestation of an ongoing sense-making process. In a series of experiments, participants were given a number of scenarios and rated surprise and probability for various hypothetical outcomes that either confirmed or disconfirmed an expectation. Experiment 1 demonstrated that representational specificity influences the relationship that holds between surprise and probability ratings. Experiment 2 demonstrated that the inclusion of an enabling event lowers surprise ratings for disconfirming outcomes. Experiment 3 explored the reason for this effect, revealing that enabling events lower surprise by reducing uncertainty, thus enhancing ease of integration. Experiment 4 evaluated the contrast hypothesis directly, showing that differences in contrast are not correlated with differences in surprise. These results provide converging support for the view that the level of surprise experienced for an event is related to the difficulty of integrating that event with an existing representation.

The influence of consistency, frequency, and semantics on learning to read: an artificial orthography paradigm.

Abstract: Two experiments explored learning, generalization, and the influence of semantics on orthographic processing in an artificial language. In Experiment 1, 16 adults learned to read 36 novel words written in novel characters. Posttraining, participants discriminated trained from untrained items and generalized to novel items, demonstrating extraction of individual character sounds. Frequency and consistency effects in learning and generalization showed that participants were sensitive to the statistics of their learning environment. In Experiment 2, 32 participants were preexposed to the sounds of all items (lexical phonology) and to novel definitions for half of these items (semantics). Preexposure to either lexical phonology or semantics boosted the early stages of orthographic learning relative to Experiment 1. By the end of training, facilitation was restricted to the semantic condition and to items containing low-frequency inconsistent vowels. Preexposure reduced generalization, suggesting that enhanced item-specific learning was achieved at the expense of character-sound abstraction. The authors' novel paradigm provides a new tool to explore orthographic learning. Although the present findings support the idea that semantic knowledge supports word reading processes, they also suggest that item-specific phonological knowledge is important in the early stages of learning to read.

Logic, beliefs, and instruction: a test of the default interventionist account of belief bias.

Abstract: According to dual-process accounts of thinking, belief-based responses on reasoning tasks are generated as default but can be intervened upon in favor of logical responding, given sufficient time, effort, or cognitive resource. In this article, we present the results of 5 experiments in which participants were instructed to evaluate the conclusions of logical arguments on the basis of either their logical validity or their believability. Contrary to the predictions arising from these accounts, the logical status of the presented conclusion had a greater impact on judgments concerning its believability than did the believability of the conclusion on judgments about whether it followed logically. This finding was observed when instructional set was presented as a between-participants factor (Experiment 1), when instruction was indicated prior to problem presentation by a cue (Experiment 2), and when the cue appeared simultaneously with conclusion presentation (Experiments 3 and 4). The finding also extended to a range of simple and more complex argument forms (Experiment 5). In these latter experiments, belief-based judgments took significantly longer than those made under logical instructions. We discuss the implications of these findings for default interventionist accounts of belief bias.

Hindsight Bias from 3 to 95 Years of Age

Abstract: Upon learning the outcome to a problem, people tend to believe that they knew it all along (hindsight bias). Here, we report the first study to trace the development of hindsight bias across the life span. One hundred ninety-four participants aged 3 to 95 years completed 3 tasks designed to measure visual and verbal hindsight bias. All age groups demonstrated hindsight bias on all 3 tasks; however, preschoolers and older adults exhibited more bias than older children and younger adults. Multinomial processing tree analyses of these data revealed that preschoolers’ enhanced hindsight bias resulted from them substituting the correct answer for their original answer in their recall (a qualitative error). Conversely, older adults’ enhanced hindsight bias resulted from them forgetting their original answer and recalling an answer closer to, but not equal to, the correct answer (a quantitative error). We discuss these findings in relation to mechanisms of memory, perspective taking, theory of mind, and executive function.

How people interpret conditionals: shifts toward the conditional event.

Abstract: We investigated how people interpret conditionals and how stable their interpretation is over a long series of trials. Participants were shown the colored patterns on each side of a 6-sided die and were asked how sure they were that a conditional holds of the side landing upward when the die is randomly thrown. Participants were presented with 71 trials consisting of all combinations of binary dimensions of shape (e.g., circles and squares) and color (e.g., blue and red) painted onto the sides of each die. In 2 experiments (N₁ = 66, N₂ = 65), the conditional event was the dominant interpretation, followed by conjunction, and material conditional responses were negligible. In both experiments, the percentage of participants giving a conditional event response increased from around 40% at the beginning of the task to nearly 80% at the end, with most participants shifting from a conjunction interpretation. The shift was moderated by the order of shape and color in each conditional's antecedent and consequent: Participants were more likely to shift if the antecedent referred to a color. In Experiment 2 we collected response times: Conditional event interpretations took longer to process than conjunction interpretations (mean difference = 500 ms). We discuss implications of our results for mental models theory and probabilistic theories of reasoning.

Working memory capacity and categorization: individual differences and modeling.

Abstract: Working memory is crucial for many higher-level cognitive functions, ranging from mental arithmetic to reasoning and problem solving. Likewise, the ability to learn and categorize novel concepts forms an indispensable part of human cognition. However, very little is known about the relationship between working memory and categorization, and modeling in category learning has thus far been largely uninformed by knowledge about people's memory processes. This article reports a large study (N = 113) that related people's working memory capacity (WMC) to their category-learning performance using the 6 problem types of Shepard, Hovland, and Jenkins (1961). Structural equation modeling revealed a strong relationship between WMC and category learning, with a single latent variable accommodating performance on all 6 problems. A model of categorization (the Attention Learning COVEring map, ALCOVE; Kruschke, 1992) was fit to the individual data and a single latent variable was sufficient to capture the variation among associative learning parameters across all problems. The data and modeling suggest that working memory mediates category learning across a broad range of tasks.

Functional Equivalence of Spatial Images from Touch and Vision: Evidence from Spatial Updating in Blind and Sighted Individuals

Abstract: This research examined whether visual and haptic map learning yield functionally equivalent spatial images in working memory, as evidenced by similar encoding bias and updating performance. In 3 experiments, participants learned 4-point routes either by seeing or feeling the maps. At test, blindfolded participants made spatial judgments about the maps from imagined perspectives that were either aligned or misaligned with the maps as represented in working memory. Results from Experiments 1 and 2 revealed a highly similar pattern of latencies and errors between visual and haptic conditions. These findings extend the well-known alignment biases for visual map learning to haptic map learning, provide further evidence of haptic updating, and most important, show that learning from the 2 modalities yields very similar performance across all conditions. Experiment 3 found the same encoding biases and updating performance with blind individuals, demonstrating that functional equivalence cannot be due to visual recoding and is consistent with an amodal hypothesis of spatial images.

Adaptive memory: determining the proximate mechanisms responsible for the memorial advantages of survival processing.

Abstract: J. S. Nairne, S. R. Thompson, and J. N. S. Pandeirada (2007) suggested that our memory systems may have evolved to help us remember fitness-relevant information and showed that retention of words rated for their relevance to survival is superior to that of words encoded under other deep processing conditions. The authors present 4 experiments that uncover the proximate mechanisms likely responsible. The authors obtained a recall advantage for survival processing compared with conditions that promoted only item-specific processing or only relational processing. This effect was eliminated when control conditions encouraged both item-specific and relational processing. Data from separate measures of item-specific and relational processing generally were consistent with the view that the memorial advantage for survival processing results from the encoding of both types of processing. Although the present study suggests the proximate mechanisms for the effect, the authors argue that survival processing may be fundamentally different from other memory phenomena for which item-specific and relational processing differences have been implicated. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

Orthography influences the perception and production of speech.

Abstract: One intriguing question in language research concerns the extent to which orthographic information impacts on spoken word processing. Previous research has faced a number of methodological difficulties and has not reached a definitive conclusion. Our research addresses these difficulties by capitalizing on recent developments in the area of word learning. Participants were trained to criterion on a set of associations between novel pictures and novel spoken words. Spelling-sound consistent or spelling-sound inconsistent spellings were introduced on the 2nd day, and the influence of these spellings on speech processing was assessed on the 3rd day. Results showed significant orthographic effects on speech perception and speech production in a situation in which spelling-sound consistency was manipulated with perfect experimental control. Results are discussed in terms of a highly interactive language system in which there is a rapid and automatic flow of activation in both directions between orthographic and phonological representations.

What limits working memory capacity? Evidence for modality-specific sources to the simultaneous storage of visual and auditory arrays.

Abstract: There is considerable debate on whether working memory (WM) storage is mediated by distinct subsystems for auditory and visual stimuli (Baddeley, 1986) or whether it is constrained by a single, central capacity-limited system (Cowan, 2006). Recent studies have addressed this issue by measuring the dual-task cost during the concurrent storage of auditory and visual arrays (e.g., Cocchini, Logie, Della Sala, MacPherson, & Baddeley, 2002; Fougnie & Marois, 2006; Saults & Cowan, 2007). However, studies have yielded widely different dual-task costs, which have been taken to support both modality-specific and central capacity-limit accounts of WM storage. Here, we demonstrate that the controversies regarding such costs mostly stem from how these costs are measured. Measures that compare combined dual-task capacity with the higher single-task capacity support a single, central WM store when there is a large disparity between the single-task capacities (Experiment 1) but not when the single-task capacities are well equated (Experiment 2). In contrast, measures of the dual-task cost that normalize for differences in single-task capacity reveal evidence for modality-specific stores, regardless of single-task performance. Moreover, these normalized measures indicate that dual-task cost is much smaller if the tasks do not involve maintaining bound feature representations in WM (Experiment 3). Taken together, these experiments not only resolve a discrepancy in the field and clarify how to assess the dual-task cost but also indicate that WM capacity can be constrained both by modality-specific and modality-independent sources of information processing.

Communicating environmental risks: Clarifying the severity effect in interpretations of verbal probability expressions

Abstract: Verbal probability expressions are frequently used to communicate risk and uncertainty. The Intergovernmental Panel on Climate Change (IPCC), for example, uses them to convey risks associated with climate change. Given the potential for human action to mitigate future environmental risks, it is important to understand how people respond to these expressions. In 3 studies employing a novel manipulation of event severity (so as to avoid any confound with event base rate), we demonstrated a systematic effect of event severity on the interpretation of verbal probability expressions. Challenging a previous finding in the literature, expressions referring to a severe event were interpreted as indicating a higher probability than those referring to a more neutral event. The finding was demonstrated in scenarios communicating risks relating to climate change (Studies 1 and 2) and replicated in scenarios involving nanotechnology and nuclear materials (Study 3). This is the first direct demonstration of an effect of outcome severity on the interpretation of verbal probability expressions, correcting a previous (potentially problematic) conclusion attributable to a flawed experimental design. (PsycINFO Database Record (c) 2011 APA, all rights reserved). Language: en

New rule use drives the relation between working memory capacity and Raven's Advanced Progressive Matrices.

Abstract: The correlation between individual differences in working memory capacity and performance on the Raven's Advanced Progressive Matrices (RAPM) is well documented yet poorly understood. The present work proposes a new explanation: that the need to use a new combination of rules on RAPM problems drives the relation between performance and working memory capacity scores. Evidence for this account is supported by an item-based analysis of performance during standard administration of the RAPM and an experiment that manipulates the need to use new rule combinations across 2 subsets of RAPM items. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

Thinking can cause forgetting: memory dynamics in creative problem solving.

Abstract: Research on retrieval-induced forgetting has shown that retrieval can cause the forgetting of related or competing items in memory (Anderson, Bjork, & Bjork, 1994). In the present research, we examined whether an analogous phenomenon occurs in the context of creative problem solving. Using the Remote Associates Test (RAT; Mednick, 1962), we found that attempting to generate a novel common associate to 3 cue words caused the forgetting of other strong associates related to those cue words. This problem-solving-induced forgetting effect occurred even when participants failed to generate a viable solution, increased in magnitude when participants spent additional time problem solving, and was positively correlated with problem-solving success on a separate set of RAT problems. These results implicate a role for forgetting in overcoming fixation in creative problem solving.

When does length cause the word length effect

Abstract: The word length effect, the finding that lists of short words are better recalled than lists of long words, has been termed one of the benchmark findings that any theory of immediate memory must account for. Indeed, the effect led directly to the development of working memory and the phonological loop, and it is viewed as the best remaining evidence for time-based decay. However, previous studies investigating this effect have confounded length with orthographic neighborhood size. In the present study, Experiments 1A and 1B revealed typical effects of length when short and long words were equated on all relevant dimensions previously identified in the literature except for neighborhood size. In Experiment 2, consonant-vowel-consonant (CVC) words with a large orthographic neighborhood were better recalled than were CVC words with a small orthographic neighborhood. In Experiments 3 and 4, using two different sets of stimuli, we showed that when short (1-syllable) and long (3-syllable) items were equated for neighborhood size, the word length effect disappeared. Experiment 5 replicated this with spoken recall. We suggest that the word length effect may be better explained by the differences in linguistic and lexical properties of short and long words rather than by length per se. These results add to the growing literature showing problems for theories of memory that include decay offset by rehearsal as a central feature.