Short-term Store Research Articles

The phonological store of working memory: A critique and an alternative, perceptual-motor, approach to verbal short-term memory.

A key quality of a good theory is its fruitfulness, one measure of which might be the degree to which it compels researchers to test it, refine it, or offer alternative explanations of the same empirical data. Perhaps the most fruitful element of Baddeley and Hitch's (1974) Working Memory framework has been the concept of a short-term phonological store, a discrete cognitive module dedicated to the passive storage of verbal material that is architecturally fractionated from perceptual, language, and articulatory systems. This review discusses how the phonological store construct has served as the main theoretical springboard for an alternative perceptual-motor approach in which serial-recall performance reflects the opportunistic co-opting of the articulatory-planning system and, when auditory material is involved, the products of obligatory auditory perceptual organisation. It is argued that this approach, which rejects the need to posit a distinct short-term store, provides a better account of the two putative empirical hallmarks of the phonological store-the phonological similarity effect and the irrelevant speech effect-and that it shows promise too in being able to account for nonword repetition and word-form learning, the supposed evolved function of the phonological store. The neuropsychological literature cited as strong additional support for the phonological store concept is also scrutinised through the lens of the perceptual-motor approach for the first time and a tentative articulatory-planning deficit hypothesis for the "short-term memory" patient profile is advanced. Finally, the relation of the perceptual-motor approach to other "emergent-property" accounts of short-term memory is briefly considered.

Gendered Memory Patterns: Unravelling Primacy and Recency Effects in Comparative Analysis

This experiment was done to see the impact of Primacy and recency Effect. Ebbinghaus demonstrated that in serial learning, words heard at the beginning and the end of the list are better memorized and recalled. It is a study that investigates in serial learning the primary effect reflects the output of the long-term store, whereas the recency effect reflects the output of short-term store. The Primacy and Recency Effect refers that items in the middle of the list are recalled poorly for at least two reasons, first they are so far from the end of list that they are not in the short-term store at the beginning of the retention test. Second, the subjects did not rehearse them extensively because only few items can be rehearsed at a time. The Primacy and Recency Effect Test requires individual to view a list of forty words, one word at a time for three seconds and asked to recall in any order. This Test demonstrates Primacy and Recency effect on recall and this outcome is called the serial position effect because the retention of an item depended upon the position effect in which it had been presented. The sample consist of total thirty subjects fifteen boys and fifteen girls. The subjects are graduate students of the age group sixteen-thirty, located in Hyderabad. In this study Simple Random Sampling is used.

Atkinson and Shiffrin’s (1968) influential model overshadowed their contemporary theory of human memory

Although every student of memory knows about the Atkinson-Shiffrin (1968) model, few know that it was advanced as a general-purpose modeling framework, not as the specific theoretical instantiation that appears in textbooks today. Largely missing from the historical record is the broader theoretical perspective proposed by Atkinson and Shiffrin (1968), one that is surprisingly consistent with contemporary views of human memory. For example, they described “working memory” (using those words) as consisting of a verbal short-term store and a visual short-term store. In addition, using logic that still makes sense today, they justified the distinction between short-term store and long-term store based on the memory profile of the amnesic patient HM, whose verbal short-term store was largely intact despite his inability to form long-term memories. Finally, they explained that some “coding processes” are more effective than others in transferring information from short-term store to long-term store, a perspective that is consistent with the subsequently proposed notion of “depth of processing.” Given its preeminent status in the history of human memory research and its enduring influence on the field today, Atkinson and Shiffrin’s 1968 chapter is reproduced here so that students of memory, including textbook writers, can better appreciate the surprisingly modern ideas they actually proposed.

Irrelevant speech impairs serial recall of verbal but not spatial items in children and adults

Immediate serial recall of visually presented items is reliably impaired by task-irrelevant speech that the participants are instructed to ignore (“irrelevant speech effect,” ISE). The ISE is stronger with changing speech tokens (words or syllables) when compared to repetitions of single tokens (“changing-state effect,” CSE). These phenomena have been attributed to sound-induced diversions of attention away from the focal task (attention capture account), or to specific interference of obligatory, involuntary sound processing with either the integrity of phonological traces in a phonological short-term store (phonological loop account), or the efficiency of a domain-general rehearsal process employed for serial order retention (changing-state account). Aiming to further explore the role of attention, phonological coding, and serial order retention in the ISE, we analyzed the effects of steady-state and changing-state speech on serial order reconstruction of visually presented verbal and spatial items in children (n = 81) and adults (n = 80). In the verbal task, both age groups performed worse with changing-state speech (sequences of different syllables) when compared with steady-state speech (one syllable repeated) and silence. Children were more impaired than adults by both speech sounds. In the spatial task, no disruptive effect of irrelevant speech was found in either group. These results indicate that irrelevant speech evokes similarity-based interference, and thus pose difficulties for the attention-capture and the changing-state account of the ISE.

Simulated performance of a solar-assisted heat pump system including a phase-change storage tank for residential heating applications: A case study in Madrid, Spain

This paper reports the simulation results of two different solar-assisted heat pump (SAHP) systems able to cover a significant part of the space heating demand of a single-family house located in Madrid (Spain) using solar energy. Most SAHP systems reported in the literature serve large buildings located in cold climates using long-term (seasonal) storage tanks, a solution that leads to high investment, operation and maintenance costs that greatly limit their applicability to milder climates and/or small-scale buildings. To explore this potential application in more detail, this study examines the integration of a water-to-water heat pump in two solar house-heating systems equipped with different short-term (diurnal) stores: water, and latent (containing a phase-change material -PCM) tanks for the weather conditions of Madrid. The SAHP system’s energy performance is assessed using the TRNSYS program, implementing in the simulation scheme an experimentally validated slab-like macro-encapsulated PCM tank model (as a TRNSYS component) for the simulations including the PCM tank. Simulation results indicated that the integration of the intermediate PCM tank in the SAHP system may perform unexpectedly, generating degradation in the system performance if only conventional thermostatic control strategies are considered, diminishing the solar energy transferred to the heat pump up to approximately a 30%, and lowering the heating availability of the system from 98.9% to 72.8%. An analysis of this thermal performance degradation led to the conclusion that more advanced control strategies based on accurate knowledge of forecasts for the following days’ heating requirements, PCM temperatures and associated states of charge of the tank from the history of the fluid inlet/outlet temperatures are required.

Stairway to memory: Left-hemispheric alpha dynamics index the progressive loading of items into a short-term store

The encoding, maintenance, and subsequent retrieval of memories over short time intervals is an essential cognitive function. Load effects on the neural dynamics supporting the maintenance of short-term memories have been well studied, but experimental design limitations have hindered the study of similar effects during the encoding of information into online memory stores. Theoretically, the active encoding of complex visual stimuli into memory must also recruit neural resources in a manner that scales with memory load. Understanding the neural systems supporting this encoding load effect is of particular importance, as some patient populations exhibit difficulties specifically with the encoding, and not the maintenance, of short-term memories. Using magnetoencephalography, a visual sequence memory paradigm, and a novel encoding slope analysis, we provide evidence for a left-lateralized network of regions, oscillating in the alpha frequency range, that exhibit a progressive loading effect of complex visual stimulus information during memory encoding. This progressive encoding load effect significantly tracked the eventual retrieval of item-order memories at the single trial level, and neural activity in these regions was functionally dissociated from that of earlier visual networks. These findings suggest that the active encoding of stimulus information into short-term stores recruits a left-lateralized network of frontal, parietal, and temporal regions, and might be susceptible to modulation (e.g., using non-invasive stimulation) in the alpha band.

CSLM: Convertible Short-Term and Long-Term Memory in Differential Neural Computers

External memory-based neural networks, such as differentiable neural computers (DNCs), have recently gained importance and popularity to solve complex sequential learning tasks that pose challenges to conventional neural networks. However, a trained DNC usually has a low-memory utilization efficiency. This article introduces a variation of DNC architecture with a convertible short-term and long-term memory, named CSLM-DNC. Unlike the memory architecture of the original DNC, the new scheme of short-term and long-term memories offers different importance of memory locations for read and write, and they can be converted over time. This is mainly motivated by the human brain where short-term memory stores large amounts of noisy and unimportant information and decays rapidly, while long-term memory stores important information and lasts for a long time. The conversion of these two types of memory is allowed and is able to be learned according to their reading and writing frequency. We quantitatively and qualitatively evaluate the proposed CSLM-DNC architecture on the tasks of question answering, copy and repeat copy, showing that it can significantly improve memory efficiency and learning performance.

Primary motor cortex and phonological recoding: A TMS-EMG study

Since the 1960s, evidence from healthy participants and brain-damaged patients, neuroimaging and non-invasive brain stimulation studies has specified the neurofunctional architecture of the short-term memory (STM) system, supporting the temporary retention of a limited amount of verbal material. Auditory-verbal, later termed Phonological (Ph) STM or Phonological Loop, comprises two sub-components: i) the main storage system, the Phonological Short-Term Store (PhSTS), to which auditory verbal stimuli have direct access and where phonologically coded information is retained for a few seconds; ii) a Rehearsal Process (REH), which actively maintains the trace held in the PhSTS, preventing its decay and conveys visual verbal material to the PhSTS, after the process of Phonological Recoding (PhREC, or Grapheme-to-Phoneme Conversion) has taken place. PhREC converts visuo-verbal graphemic representations into phonological ones. The neural correlates of PhSTM include two discrete regions in the left hemisphere: the temporo-parietal junction (PhSTS) and the inferior frontal gyrus in the premotor cortex (REH). The neural basis of PhREC has been much less investigated. A few single case studies of patients made anarthric by focal or degenerative cortical damage, who show a pattern of impairment indicative of a deficit of PhREC, sparing the REH process, suggest that the primary motor cortex (M1) might be involved. To test this hypothesis in healthy participants with a neurophysiological approach, we measured the corticospinal excitability of M1, by means of Transcranial Magnetic Stimulation (TMS)-induced Motor Evoked Potentials (MEPs), during the execution of phonological judgements on auditorily vs. visually presented words (Experiment #1). Crucially, these phonological tasks involve REH, while PhREC is required only with visual presentation. Results show MEPs with larger amplitude when stimuli are presented visually. Task difficulty does not account for this difference and the result is specific for linguistic stimuli, indeed visual and auditory stimuli that cannot be verbalized lead to different behavioral and neurophysiological patterns (Experiment #2). The increase of corticospinal excitability when words are presented visually can be then interpreted as an indication of the involvement of M1 in PhREC. The present findings elucidate the neural correlates of PhREC, suggesting an involvement of the peripheral motor system in its activity.

On some of the main criticisms of the modal model: Reappraisal from a TBRS perspective.

The model developed by Atkinson and Shiffrin describes memory as a flow of information that enters and leaves a short-term storage and that in some cases consolidates into a long-term store. Their model has stimulated 50 years of memory research and, like every model, has also received several criticisms. It has been argued that a single short-term store in charge of both maintaining memory items and processing other cognitive tasks is not plausible. Some authors have evaluated the proposal of a rehearsal process as the unique way to transfer information into long-term memory as not being likely. Finally, the idea that information decays from the short-term store in the absence of rehearsal maintaining the memory traces has been and is still debated in the working memory literature. In this article, we reconsider these criticisms and show why they are not totally legitimate. We describe a recent working memory model, the time-based resource-sharing (TBRS) model (Barrouillet, P., & Camos, V. (2015). Working memory: Loss and reconstruction. Hove, UK: Psychology Press), that shares several theoretical assumptions with the model initially proposed by Atkinson and Shiffrin, assumptions supported by empirical findings. Consequently, the model proposed by Atkinson and Shiffrin in 1968 may be far from outdated and still provide an inspiring framework for memory study.

Visual Attention Modulates Phenomenal Consciousness: Evidence From a Change Detection Study.

The distinction between phenomenal and access consciousness has been influential in the field of consciousness studies. Both Block and Lamme proposed that access consciousness, or narrow cognitive accessibility, is related to a limited capacity working memory, and that phenomenal consciousness, or broad cognitive accessibility, is related to iconic memory or, more recently, to a fragile (intermediate) short-term memory store with a larger capacity than working memory. They have also highlighted the preattentive nature of phenomenal consciousness and of the related iconic and fragile visual short-term stores, thus selectively linking attention with access consciousness, in line with Baars and Dehaene, among others. However, a range of electrophysiological and neurophysiological studies suggest that visual attention can affect early responses of neurons in visual cortex, before conscious access. Furthermore, some theories and neurocomputational models suggest earlier attentional biases related to phenomenal consciousness. To solve this controversy, and to shed light on the relationships of attention with iconic memory and subsequent stages of visual maintenance, we conducted an experiment with a novel procedure of change detection based on delayed cueing of the target for report with high- and low-priority objects marked by color. In line with our hypothesis, the results show an attentional bias toward high-priority objects in the memory array with the longer (600 and 1,200 ms) cueing delays associated with a fragile (intermediate) visual short-term memory, but not with the shorter cueing delays (16.6 and 200 ms) associated with iconic memory. These findings therefore suggest two stages of phenomenal consciousness before access consciousness: a first preattentive stage related to iconic memory and a second stage related to fragile visual short-term memory intermediate between iconic and visual working memory, which is modulated by visual attention in a time-dependent manner. Finally, our results suggest the dissociation between a mid-level visual attention modulating phenomenal consciousness and a central attention directing access consciousness.

Even an activated long-term memory system still needs a separate short-term store: A reply to Cowan (2019).

In Norris (2017), I explained why the notion of activated LTM (long-term memory) combined with a focus of attention was unable to perform the computations required to support short-term memory (STM) and argued that those extra computations must require a separate STM system. Cowan (2019) made the alternative proposal that this full set of computations is better conceptualized as a unitary system of activated LTM. To this he added a pointer system, the ability to perform variable binding, and an unspecified model of STM that acts as a front end to LTM. This appears to be simply an exercise in relabeling. Furthermore, without a computational specification of how the components work, the model lacks the ability to simulate even the most basic STM phenomena. If the model were specified in more detail it seems almost inevitable that it would contain something instantly recognizable as an STM system.

Abstract #37: Closed-Loop tACS Targeting Slow-Wave Oscillations During Sleep Enhances Consolidation of Generalized Information

Introduction: Sleep is critically important to consolidate information learned throughout the day, and is hypothesized to promote the consolidation of information from short-term stores to more schematized long-term representations (Sterpenich et al., 2014; Friedrich et al., 2014; Stickgold & Walker, 2013; Fenn et al., 2003). Slow-wave sleep (SWS) serves to consolidate declarative memories, a process previously modulated with open-loop non-invasive electrical stimulation, though not always effectively (Eggert et al., 2013; Sahlem et al., 2015). The failure to replicate could be explained by the fact that stimulation has only been performed in open loop, as opposed to closed-loop where phase and frequency of the endogenous slow-wave oscillations (SWOs) are matched for optimal timing. The current study investigated the effects of closed-loop transcranial Alternating Current Stimulation (tACS) targeting SWOs during sleep on memory consolidation.

Information processing in a sensorimotor operation: Atkinson and Shiffrinrsquo;s model revisited

Authors present the model of memory by Atkinson and Shiffrin as a starting point to a new interpretation and base for new model of information processing in humans. They point to the fact that already in their seminal paper, Atkinson and Shiffrin mentioned about some control processes. Therefore, though they termed specific units of memory “sensory register”, “short term store” and “long term store”, in their model information was not only preserved, but also somehow processed in particular “memory drawers”. The authors of this paper assume that the base of science are facts and observation, but it consists of interpretations and theories. Hence, the same facts may be interpret differently by different scientists. In the paper they present another concept of human memory, less mathematical, but more psychological than that by Atkinson and Shiffrin.

“The case against specialized visual-spatial short-term memory”: Correction to Morey (2018).

Reports an error in "The case against specialized visual-spatial short-term memory" by Candice C. Morey (Psychological Bulletin, 2018[Aug], Vol 144[8], 849-883). In the article, the text describing the case reports of patient E. L. D. (Hanley, Pearson, & Young, 1990, Hanley, Young, & Pearson, 1991) the text should read that E. L. D. had difficulties compared to a control sample choosing which of 20 faces (rather than 12 faces) she had recently seen. Later in the same section, the text should read "she had little difficulty recognizing which of two familiar faces she had encountered in a recent experimental session . . . .", rather than unfamiliar. Discussion with the original authors of the case reports describing E. L. D. also clarified a methodological point in their original report (Hanley, et al., 1990). The original report says that E. L. D. was given a recognition test for which particular view of an object she observed a month later. This in fact meant that E. L. D. undertook the entire task a month later than the other tasks in the set, not that she received the recognition test a month after exposure. None of these errors impact Morey's (2018) conclusions, including the conclusion that E. L. D.'s case does not meet the criteria for an unambiguous, selective visual-spatial short-term memory deficit. (The following abstract of the original article appeared in record 2018-24700-001.) The dominant paradigm for understanding working memory, or the combination of the perceptual, attentional, and mnemonic processes needed for thinking, subdivides short-term memory (STM) according to whether memoranda are encoded in aural-verbal or visual formats. This traditional dissociation has been supported by examples of neuropsychological patients who seem to selectively lack STM for either aural-verbal, visual, or spatial memoranda, and by experimental research using dual-task methods. Though this evidence is the foundation of assumptions of modular STM systems, the case it makes for a specialized visual STM system is surprisingly weak. I identify the key evidence supporting a distinct verbal STM system-patients with apparent selective damage to verbal STM and the resilience of verbal short-term memories to general dual-task interference-and apply these benchmarks to neuropsychological and experimental investigations of visual-spatial STM. Contrary to the evidence on verbal STM, patients with apparent visual or spatial STM deficits tend to experience a wide range of additional deficits, making it difficult to conclude that a distinct short-term store was damaged. Consistently with this, a meta-analysis of dual-task visual-spatial STM research shows that robust dual-task costs are consistently observed regardless of the domain or sensory code of the secondary task. Together, this evidence suggests that positing a specialized visual STM system is not necessary. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

From short-term store to multicomponent working memory: The role of the modal model.

The term "modal model" reflects the importance of Atkinson and Shiffrin's paper in capturing the major developments in the cognitive psychology of memory that were achieved over the previous decade, providing an integrated framework that has formed the basis for many future developments. The fact that it is still the most cited model from that period some 50 years later has, we suggest, implications for the model itself and for theorising in psychology more generally. We review the essential foundations of the model before going on to discuss briefly the way in which one of its components, the short-term store, had influenced our own concept of a multicomponent working memory. This is followed by a discussion of recent claims that the concept of a short-term store be replaced by an interpretation in terms of activated long-term memory. We present severalreasons to question theseproposals. We conclude with a brief discussion of the implications of the longevity of the modal model for styles of theorising in cognitive psychology.

Serial position-dependent false memory effects

ABSTRACTEvidence for false recognition within seconds of encoding suggests that semantic-associative influences are not restricted to long-term memory, consistent with unitary memory accounts but contrary to dual store models. The present study sought further relevant evidence using a modified free recall converging associates task where participants studied 12-item lists composed of 3 semantically distinct quartets (sublists) related to a separate, non-presented theme word (i.e., words 1–4/theme1, 5–8/theme2, and 9–12/theme3). This list construction permits assessment of false recall errors from each sublist, and, particularly, the primacy and recency sublists that have been linked to long- and short-term memory stores. Experiment 1 tested immediate free recall for items. Associative false memories were evident from all sublists, however, significantly less so from the recent sublist, which also showed the highest levels of veridical memory. By inserting a brief (3 s) distractor prior to recall, Experiment 2 selectively reduced veridical memory and increased false memory for the recent sublist while leaving the primacy sublist unaffected. These recall results converge with prior evidence indicating the immediacy of false recognition, and can be understood within a unitary framework where the differential availability of verbatim features and gist-based cues affect memory for primacy and recency sublists.

The case against specialized visual-spatial short-term memory.

The dominant paradigm for understanding working memory, or the combination of the perceptual, attentional, and mnemonic processes needed for thinking, subdivides short-term memory (STM) according to whether memoranda are encoded in aural-verbal or visual formats. This traditional dissociation has been supported by examples of neuropsychological patients who seem to selectively lack STM for either aural-verbal, visual, or spatial memoranda, and by experimental research using dual-task methods. Though this evidence is the foundation of assumptions of modular STM systems, the case it makes for a specialized visual STM system is surprisingly weak. I identify the key evidence supporting a distinct verbal STM system-patients with apparent selective damage to verbal STM and the resilience of verbal short-term memories to general dual-task interference-and apply these benchmarks to neuropsychological and experimental investigations of visual-spatial STM. Contrary to the evidence on verbal STM, patients with apparent visual or spatial STM deficits tend to experience a wide range of additional deficits, making it difficult to conclude that a distinct short-term store was damaged. Consistently with this, a meta-analysis of dual-task visual-spatial STM research shows that robust dual-task costs are consistently observed regardless of the domain or sensory code of the secondary task. Together, this evidence suggests that positing a specialized visual STM system is not necessary. (PsycINFO Database Record

Artificial Seed Production of Tylophora indica for Interim Storing and Swapping of Germplasm

Our research work demonstrates the single bead alginate-encapsulation, interim storing and conversion of Tylophora indica (Burm. Fil.) Merrill. Most effective encapsulation of in vitro nodal segments [(4 ± 1) mm long], ensuing in sphere-shaped artificial seeds of similar morphology, was achieved through 75 mmol⋅L−1 calcium chloride (CaCl2 ⋅ 2H2O) plus 3% (w/v) Na-alginate with 93.3% conversion frequency. The earliest conversion (within 7 days of incubation) of artificial seeds occurred in half-strength liquid Murashige and Skoog medium. Among the three different temperature regimes [(5 ± 1) °C, (15 ± 1) °C, and (25 ± 1) °C], storage of artificial seeds at (15 ± 1) °C executed the highest frequency of conversion (90%) after 15 days of storage. Lengthier storage significantly reduced the conversion frequency of artificial seeds irrespective of storage temperature. Nevertheless, the conversion frequency after 30 days of storage at (15 ± 1) °C was recorded at 70% without further decline even following 45 days of storage, which evidently suggests that lower temperature (15 ± 1) °C is apt for storage and subsequent conversion of T. indica artificial seeds. The present protocol could be expedient for short-term storing and swapping of T. indica germplasms between national and international laboratories.

Individual personality associated with interactions between physiological condition and the environment

An emerging focus of behavioural ecology is to determine the driving forces behind animal personalities. While numerous theories have been proposed to explain these behavioural variations, empirical studies on this subject remain lacking. Here, we test ecological theory by studying the combined effects of physiological condition and habitat quality on the behaviour of individual mud crabs, Panopeus herbstii, across the spawning season (early spawning season and 2 months after). We assessed the boldness, energy stores and reproductive effort of crabs collected across 10 oyster reefs of low and high quality using laboratory observations and subsequent dissections. Crab boldness was significantly dependent on the interaction between habitat quality and season. While crab behaviour remained relatively constant on healthy reefs, crabs on degraded reefs exhibited a nearly two-fold increase in boldness during the late spawning season, approximating the boldness of crabs on healthy reefs. This behavioural change corresponds to a seasonal shift in crab energy store content and is likely to represent a switch in the primary driving force of crab behaviour. During the early season, crab boldness was positively correlated with short-term stores, whereas later in the season, crab boldness was negatively correlated with long-term stores. Our results suggest that behaviour is driven by predation pressure and refuge availability during the early spawning season, but afterwards depends on replenishing energy stores used for reproduction. These findings support ecological theory and also provide new insight into the stability of behavioural drivers.

Memory function and short-term store as a psychological construct : Implications of a working memory framework(Multidisciplinary perspectives on human memory,Symposium 2 at the 24th Annual Meeting)

Memory function and short-term store as a psychological construct : Implications of a working memory framework(Multidisciplinary perspectives on human memory,Symposium 2 at the 24th Annual Meeting)