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There is a recent surge of interest in maintenance processes in working memory, such as articulatory rehearsal, elaboration, and attentional refreshing. Yet, we know little about the central attentional demand of these processes. It has been assumed that articulatory rehearsal does not require central attention at all (Vergauwe, Camos, & Barrouillet, 2014), being in essence a cost-free strategy. In contrast, elaboration and attentional refreshing are assumed to incur large and continuous costs on central attention. We tested these assumptions in three experiments in which participants were presented with a varying number of words to rehearse. Participants were instructed to rehearse the words aloud, or to elaborate them by creating interactive images. Attentional refreshing was examined in a condition in which words were to be maintained during articulatory suppression. During retention participants carried out a series of choice reaction tasks, which were used to measure central attentional demands of the maintenance strategies. Articulatory rehearsal had costs on processing RTs that lasted for 10 s. Maintenance of words during articulatory suppression did not yield persistent costs on central attention, implying that participants did not continuously refresh the words. Finally, the current results cast doubt on the idea that elaboration requires central attention for an extended period of time. All experimental scripts and data sets reported here are available online ( https://osf.io/69p8j/ ).

Most studies of visual-working memory employ one of two experimental paradigms: change-detection or continuous-stimulus reproduction. In this study, we extended the Interference Model (IM; OberauerLin, 2017), which was designed for continuous reproduction, to the single-probe change-detection task. In continuous reproduction, participants occasionally report the non-target items instead of the target. The presence of non-target response is predicted by the Interference Model, which relies in part on the interference of non-target items to explain the set-size effect. By presenting a probe matching a non-target item, we can investigate the amount of interference from non-target items in change detection. As predicted by the Interference Model, we observed poorer performance in rejecting a probe matching a non-target item compared to a new probe (i.e., a cost due to intrusions from non-targets). We fitted the IM along with the Variable Precision, the Slot-Averaging, and the Neural-Population model to the data from two change-detection experiments. The models were equipped with a Bayesian decision rule based on the one used in Keshvari, van den Berg, and Ma (2013). The Interference Model and the Neural-Population model successfully predicted the set-size effect and the non-target intrusion cost, whereas the Variable Precision (VP) and Slot-Averaging (SA) models failed to predict the intrusion cost at all. Even with additional assumptions enabling VP and SA to produce intrusion costs, the IM still performed better than the competing models quantitatively.

Although virtually all experts agree that CO2 emissions are causing anthropogenic global warming, public discourse is replete with contrarian claims that either deny that global warming is happening or dispute a human influence. Although the rejection of climate science is known to be driven by ideological, psychological, and political factors rather than scientific disagreement, contrarian views have considerable prominence in the media. A better understanding of contrarian discourse is therefore called for. We report a blind expert test of contrarian claims about climatological variables. Expert economists and statisticians were presented with representative contrarian statements (e.g., “Arctic ice is recovering”) translated into an economic or demographic context. In that blind test, contrarian claims were found to be misleading. By contrast, mainstream scientific interpretations of the data were judged to be accurate and policy relevant. The results imply that media inclusion of contrarian statements may increase bias rather than balance.

Previous research has claimed that working memory (WM) updating is one of three primary central executive processes, and the only one to reliably predict fluid intelligence. However, standard WM updating tasks confound updating requirements with generic WM functions. This article introduces a method for isolating a process unique to WM updating, namely the removal of no-longer relevant information. In a modified version of an established updating paradigm, to-be-updated items were cued before the new memoranda were presented. Overall, longer cue-target intervals—that is, longer time available for removal of outdated information—led to faster updating, suggesting that people can actively remove information from WM. Experiments 1 and 2 demonstrated that well-established effects of item repetition and similarity on updating RTs were diminished with longer cue-target interval, arguably because representational overlap between outdated and new information becomes less influential when outdated information can be removed prior to new encoding. Experiment 3 looked at individual differences, using the reduction of updating RTs to measure removal speed. Removal speed was measured reliably but was uncorrelated to WM capacity. We conclude that (1) removal of outdated information can be experimentally isolated and measured reliably, (2) removal speed is a unique, active WM updating ability, and (3) the view of WM updating as a core executive process that uniquely predicts fluid abilities is overstated.

The ability to keep working memory content up to date is vital for a number of higher cognitive functions such as navigation and reasoning, but it is also crucial for the effective operation of working memory itself. Removing outdated or irrelevant information allows focused processing of relevant information, and minimizes interference. We present evidence from three experiments that (1) people utilize an active removal process to update working memory, (2) that this removal process is an item-specific operation, and (3) that updating subsets of information held in working memory involves switching between maintenance and updating modes of working memory.

Theories assuming that representations in working memory decay unless maintained by rehearsal must predict that in any condition where rehearsal does not fully counteract decay, memory declines with a longer retention interval. Two experiments served to test this prediction in a complex-span paradigm in which encoding of letters for later recall alternated with series of spatial distractor operations. The opportunity for rehearsal was varied through cognitive load, the proportion of available time per distractor operation that was actually needed for that operation. The time needed for each operation within a series was measured independently. Retention interval was varied by increasing the number of operations at constant cognitive load. Memory declined with higher cognitive load, but was unchanged (Experiment 1) or improved (Experiment 2) with more distractor operations. Decay theories can explain the effect of cognitive load by assuming that at high load rehearsal fails to fully compensate decay, but then must predict a negative effect of the number of operations at higher cognitive load, contrary to the data. Simulations with an interference-based computational model of working memory, SOB-CS, show that the model explains the experimental findings.

The impact of working memory training on a broad set of transfer tasks was examined. Each of three groups of participants trained one specific functional category of working memory capacity: storage and processing, relational integration, and supervision. A battery comprising tests to measure working memory, task shifting, inhibition, and reasoning was administered before, immediately after, and 6 months after 4 weeks of computer-based training. Training groups were compared to an active control group practicing perceptual matching tasks. Data were analyzed with linear mixed-effects models that revealed distinct transfer profiles for the experimental groups: Storage-Processing training had an effect on working memory and reasoning, and Supervision training improved task shifting and reasoning. There was no such broad transfer of Relational Integration training. The degree of improvement in the training tasks correlated positively with the magnitude of transfer. Differential effects of training different functional categories of working memory and executive functions could explain why previous studies yielded mixed results: Training specific processes leads to transfer on specific cognitive constructs only.

The article investigates the mechanisms of selecting and updating representations in declarative and procedural working memory (WM). Declarative WM holds the objects of thought available, whereas procedural WM holds representations of what to do with these objects. Both systems consist of three embedded components: activated long-term memory, a central capacity-limited component for building structures through temporary bindings, and a single-element focus of attention. Five experiments test the hypothesis of analogous mechanisms in declarative and procedural WM, investigating repetition effects across trials for individual representations (objects and responses) and for sets (memory sets and task sets), as well as set-congruency effects. Evidence for analogous processes was obtained from three phenomena: (1) Costs of task switching and of list switching are reduced with longer preparation interval. (2) The effects of task congruency and of list congruency are undiminished with longer preparation interval. (3) Response repetition interacts with task repetition in procedural WM; here we show an analogous interaction of list repetition with item repetition in declarative WM. All three patterns were reproduced by a connectionist model implementing the assumed selection and updating mechanisms. The model consists of two modules, an item-selection module selecting individual items from a memory set, or responses from a task set, and a set-selection module for selecting memory sets or task sets. The model codes the matrix of binding weights in the item-selection module as a pattern of activation in the set-selection module, thereby providing a mechanism for building chunks in LTM, and for unpacking them as structures into working memory.

Many models of short-term memory (STM) ascribe an important role to temporal decay and forgetting because of the passage of time alone. We argue against decay as the primary form of forgetting from STM, and suggest that new experimental methodologies and recent models provide new perspectives on the old issue of the causes of forgetting. We show that several classic sources of evidence for time-based forgetting can be re-interpreted in terms of an interference-based view, and that new experiments provide compelling evidence against decay. We conclude that progress requires moving beyond demonstrations of qualitative effects and focusing instead on testing quantitative predictions of models.

This article presents four experiments that tested predictions of SOB (Serial Order in a Box), an interference-based theory of short-term memory. Central to SOB is the concept of novelty-sensitive encoding, which holds that items are encoded to the extent that they differ from already-encoded information. On the additional assumption that distractors are encoded into memory in the same manner as list items, the theory predicts differential effects of interfering activity based on the similarity structure of distractors. Consistent with predictions, three experiments showed that overt articulation of distractors in between recalls of list items did not affect forgetting when the same distractor was repeated multiple times, whereas forgetting was observed if several different distractors were articulated within the same time span. A fourth experiment showed that the absence of forgetting with repeated articulations of the same item was not due to compensatory attentional refreshing of memory traces. The data support the notion that forgetting from short-term memory arises from interference and are difficult to reconcile with temporal decay.

Reports two experiments on mechanism of interference in working memory. Experiment 1 shows that a target word in a memory list, which bears high similarity to one of 4 words read aloud in the retention interval, is recalled less well than a control word. A second target word, not similar to any word read aloud but with all its phonemes repeated among the words read aloud, suffered the same degree of impairment. Feature overwriting explains both results, whereas similarity-based confusion explains only the first. In Experiment 2, participants remembered lists of 4 words, followed by 4 letters. A target word with high phoneme overlap with the letters was recalled worse than a control word, in line with predictions from feature overwriting. A further target word with many phonological neighbors created by inserting letter phonemes into it was recalled better than a control, contrary to predictions from feature migration.

Investigated the distinctiveness of working memory functions and their components against the background of a multi-facet model. 133 university students (mean age 26 years) performed a series of specially constructed working memory tasks. Each task represented an operationalization of specific cells of the proposed taxonomy of working memory functional and content-related facets. Dependent variables included recall performance and reaction time. Structural equation modeling yielded 3 distinct working memory functions: (1) simultaneous storage of information in the context of processing, (2) supervision, and (3) coordination of elements into structures. Further analyses allowed for a more detailed subdivision of each function into specific components. Only a minimal portion of the variance associated with working memory functions is specific to the verbal or the spatial domain. Overall, the findings demonstrate that working memory is best characterized as a highly interrelated collection of cognitive functions.

Altmann raises two objections to our conclusion that short-term forgetting is caused by interference rather than decay [1]. He (i) makes the functional argument that decay is needed for cognitive ‘garbage collection’ and (ii) offers supporting task-switching data that show that responding to an identical task slows over trials in a run, ostensibly because the task set decays.

In their opinion article, Lewandowsky, Oberauer andBrown [1] make a strong case against time-based accountsofforgettinginshort-termandworkingmemory.Weargue,however, that the interference-based account they favor isunderspecified, that the time-loss functions predicted bytime-based models are misconstrued and that the contra-dictory findings issued from the time-based resource-shar-ing (TBRS) model [2] are not properly addressed.First, it is often overlooked that interference-basedtheories are vague, as Lewandowsky et al. [1] themselvesacknowledge when outlining outstanding questions. Someof the same authors have elsewhere argued that forgettingiscausedbytheoverlapoffeatures[3,4],butthesefeaturesare poorly specified. For example, Lewandowsky et al. [1]deny that the disruptive effect of judging the spatiallocationofsquaresonthemaintenanceofletters[5]results