- More is generally better: Higher working memory capacity does not impair perceptual category learning.
It is sometimes supposed that category learning involves competing explicit and procedural systems, with only the former reliant on working memory capacity (WMC). In 2 experiments participants were trained for 3 blocks on both filtering (often said to be learned explicitly) and condensation (often said to be learned procedurally) category structures. Both experiments (total N = 160) demonstrated that participants with higher WMC tended to be more accurate in condensation tasks, but not less accurate in filtering tasks. Furthermore, state-trace analysis did not find a differential influence of WMC on performance in these tasks. Finally, inspection of the mixture of response strategies at play across the 2 conditions and 3 blocks showed only a minor influence of WMC, and then only on later training blocks. The results provide no support for the existence of a “system” of category learning that is independent of working memory and are instead consistent with most single-system interpretations of category learning. (PsycINFO Database Record (c) 2017 APA, all rights reserved)
- Dependent measure and time constraints modulate the competition between conflicting feature-based and rule-based generalization processes.
In our study, we tested the hypothesis that feature-based and rule-based generalization involve different types of processes that may affect each other producing different results depending on time constraints and on how generalization is measured. For this purpose, participants in our experiments learned cue–outcome relationships that followed the opposites rule: Single cues that signaled the same outcome (e.g., A-1/B-1) predicted the opposite outcome when presented in compound (e.g., AB-2). Some cues were only presented in compound during training (e.g., EF-1) to see if at test participants tended to generalize according to rule-based (i.e., E-2/F-2) or according to feature-based generalization (i.e., E-1/F-1). The generalization test used 2 different tasks: a predictive judgment task, and a cued-response priming task. In Experiment 1, participants’ verbal ratings were consistent with rule-based generalization. However, participants’ reaction times (RTs) in the cued-response priming task were consistent with feature-based generalization. Experiment 2 replicated the results from Experiment 1, and it also provided evidence consistent with feature-based or rule-based generalization depending on whether a short stimulus onset asynchrony (SOA; 200 ms) or a long SOA (1300 ms), respectively, was used in the priming task. Our results are interpreted as supporting the idea that feature-based generalization process relies on fast, associative processes, whereas rule-based generalization is slow and depends on executive control resources. The latter generalization process would inhibit the former when enough time and resources are available. Otherwise, feature-based generalization would take control of responses. (PsycINFO Database Record (c) 2017 APA, all rights reserved)
- Rapid forgetting results from competition over time between items in visual working memory.
Working memory is now established as a fundamental cognitive process across a range of species. Loss of information held in working memory has the potential to disrupt many aspects of cognitive function. However, despite its significance, the mechanisms underlying rapid forgetting remain unclear, with intense recent debate as to whether it is interference between stored items that leads to loss of information or simply temporal decay. Here we show that both factors are essential and interact in a highly specific manner. Although a single item can be maintained in memory with high fidelity, multiple items compete in working memory, progressively degrading each other’s representations as time passes. Specifically, interaction between items is associated with both worsening precision and increased reporting errors of object features over time. Importantly, during the period of maintenance, although items are no longer visible, maintenance resources can be selectively redeployed to protect the probability to recall the correct feature and the precision with which cued items can be recalled, as if it was the only item in memory. These findings reveal that the biased competition concept could be applied not only to perceptual processes but also to active maintenance of working memory representations over time. (PsycINFO Database Record (c) 2017 APA, all rights reserved)
- The functional determinants of short-term memory: Evidence from perceptual-motor interference in verbal serial recall.
A functional, perceptual-motor, account of serial short-term memory (STM) is examined by investigating the way in which an irrelevant spoken sequence interferes with verbal serial recall. Even with visual list-presentation, verbal serial recall is particularly susceptible to disruption by irrelevant spoken stimuli that have the same identity as—but that are order-incongruent with—the to-be-remembered items. We test the view that such interference is because of the obligatory perceptual organization of the spoken stimuli yielding a sequence that competes with a subvocal motor-plan assembled to support the reproduction of the to-be-remembered list. In support of this view, the interference can be eliminated without changing either the identities or objective serial order of the spoken stimuli but merely by promoting a subjective perceptual organization that strips them of their order-incongruent relation to the to-be-remembered list (Experiment 1). The interference is also eliminated if subvocal motor sequence-planning is impeded via articulatory suppression (Experiment 2). The results are in line with the view that performance-limits in verbal serial STM are because of having to exploit perceptual and motor processes for purposes for which they did not evolve, not the inherently limited capacity of structures or mechanisms dedicated to storage. (PsycINFO Database Record (c) 2017 APA, all rights reserved)
- Confidence in forced-choice recognition: What underlies the ratings?
Two-alternative forced-choice recognition tests are commonly used to assess recognition accuracy that is uncontaminated by changes in bias. In such tests, participants are asked to endorse the studied item out of 2 presented alternatives. Participants may be further asked to provide confidence judgments for their recognition decisions. It is often assumed that both recognition decisions and confidence judgments in 2-alternative forced-choice recognition tests depend on participants’ assessments of a difference in strength of memory evidence supporting the 2 alternatives—the relative account. In the present study we focus on the basis of confidence judgments and we assess the relative account of confidence against the absolute account of confidence, by which in assigning confidence participants consider only strength of memory evidence supporting the chosen alternative. The results of the study show that confidence in 2-alternative forced-choice recognition decisions is higher when memory evidence is stronger for the chosen alternative and also when memory evidence is stronger for the unchosen alternative. These patterns of results are consistent with the absolute account of confidence in 2-alternative forced-choice recognition but they are inconsistent with the relative account. (PsycINFO Database Record (c) 2017 APA, all rights reserved)
- “Strategic control over extent and timing of distractor-based response activation”: Correction to Jost et al. (2017).
Reports an error in “Strategic control over extent and timing of distractor-based response activation” by Kerstin Jost, Mike Wendt, Aquiles Luna-Rodriguez, Andreas Löw and Thomas Jacobsen (Journal of Experimental Psychology: Learning, Memory, and Cognition, 2017[Feb], Vol 43, 326-333). In the article, the images to Figures 2 and 3 were switched during production. The online version of this article has been corrected. (The following abstract of the original article appeared in record 2016-48458-001.) In choice reaction time (RT) tasks, performance is often influenced by the presence of nominally irrelevant stimuli, referred to as distractors. Recent research provided evidence that distractor processing can be adjusted to the utility of the distractors: Distractors predictive of the upcoming target/response were more attended to and also elicited stronger motor responses. In an event-related potential (ERP) study, we investigated whether not only the extent of distractor processing (as suggested by these previous results), but also the timing of distractor-based response activation is subject to strategic control. In a temporal flanker task, in which a distractor stimulus preceded the target, we manipulated distractor utility (i.e., by varying the proportion of congruent distractor–target combinations, 75% vs. 25%) as well as the stimulus onset asynchrony (SOA) between distractors and targets (350 ms vs. 1,000 ms) in different blocks of trials. The distractor-locked lateralized readiness potential (LRP) was overall larger in blocks with a high proportion of congruent trials indicating stronger distractor-based response activation when distractor utility was high. Of importance, the LRPs occurred overall later when the SOA was long. This suggests that distractor-based response activation can be postponed and thus adjusted to the temporal factors of the context. Modulations of early visual potentials (P1 and N1) indicate that this postponement of motor activation is related to both sensory-perceptual downgrading of distractor stimuli and reduced activation of task-relevant stimulus–response transformation processes at the time of distractor perception. (PsycINFO Database Record (c) 2017 APA, all rights reserved)
- Orthographic neighborhood effects in recognition and recall tasks in a transparent orthography.
The number of orthographic neighbors of a word influences its probability of being retrieved in recognition and free recall memory tests. Even though this phenomenon is well demonstrated for English words, it has yet to be demonstrated for languages with more predictable grapheme–phoneme mappings than English. To address this issue, 4 experiments were conducted to investigate effects of number of orthographic neighbors (N) and effects of frequency of occurrence of orthographic neighbors (NF) on memory retrieval of Brazilian Portuguese words. One hundred twenty-four Brazilian Portuguese speakers performed first a lexical-decision task (LDT) on words that were factorially manipulated according to N and NF, and intermixed with either nonpronounceable nonwords without orthographic neighbors (Experiments 1A and 2A), or with pronounceable nonwords with a large number of orthographic neighbors (Experiments 1B and 2B). The words were later used as probes on either recognition (Experiments 1A and 1B) or recall tests (Experiments 2A and 2B). Words with 1 orthographic neighbor were consistently better remembered than words with several orthographic neighbors in all recognition and recall tests. Notably, whereas in Experiment 1A higher false alarm rates were yielded for words with several rather than 1 orthographic neighbor, in Experiment 1B higher false alarm rates were yielded for words with 1 rather than several orthographic neighbors. Effects of NF, on the other hand, were not consistent among memory tasks. The effects of N on the recognition and recall tests conducted here are interpreted in light of dual process models of recognition. (PsycINFO Database Record (c) 2017 APA, all rights reserved)
- Reading sky and seeing a cloud: On the relevance of events for perceptual simulation.
Previous research has shown that processing words with an up/down association (e.g., bird, foot) can influence the subsequent identification of visual targets in congruent location (at the top/bottom of the screen). However, as facilitation and interference were found under similar conditions, the nature of the underlying mechanisms remained unclear. We propose that word comprehension relies on the perceptual simulation of a prototypical event involving the entity denoted by a word in order to provide a general account of the different findings. In 3 experiments, participants had to discriminate between 2 target pictures appearing at the top or the bottom of the screen by pressing the left versus right button. Immediately before the targets appeared, they saw an up/down word belonging to the target’s event, an up/down word unrelated to the target, or a spatially neutral control word. Prime words belonging to target event facilitated identification of targets at a stimulus onset asynchrony (SOA) of 250 ms (Experiment 1), but only when presented in the vertical location where they are typically seen, indicating that targets were integrated in the simulations activated by the prime words. Moreover, at the same SOA, there was a robust facilitation effect for targets appearing in their typical location regardless of the prime type. However, when words were presented for 100 ms (Experiment 2) or 800 ms (Experiment 3), only a location nonspecific priming effect was found, suggesting that the visual system was not activated. Implications for theories of semantic processing are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved)