The real relationship between short-term memory and working memory

Storage-oriented memory span tasks with no explicit concurrent processing are usually referred as short-term memory (STM) tasks, whereas tasks involving storage plus concurrent processing requirements are designated as working memory (WM) tasks. The present study explores a question that remains unsolved: Do STM and WM tasks clearly tap distinguishable theoretical constructs? For that purpose, a large sample of 403 participants was tested through 12 diverse memory span tasks. Half of those tasks are widely accepted as measures of STM, whereas the other half measure WM. The results show that STM and WM share largely overlapping underlying capacity limitations, suggesting that all memory span tasks tap essentially the same construct. Some implications are discussed.     

The real relationship between short-term memory and working memory

Storage-oriented memory span tasks with no explicit concurrent processing are usually referred as short-term memory (STM) tasks, whereas tasks involving storage plus concurrent processing requirements are designated as working memory (WM) tasks. The present study explores a question that remains unsolved: Do STM and WM tasks clearly tap distinguishable theoretical constructs? For that purpose, a large sample of 403 participants was tested through 12 diverse memory span tasks. Half of those tasks are widely accepted as measures of STM, whereas the other half measure WM. The results show that STM and WM share largely overlapping underlying capacity limitations, suggesting that all memory span tasks tap essentially the same construct. Some implications are discussed.     

Distinguishing short-term memory from working memory

The aim of the present research was to determine whether short-term memory and working memory could be distinguished. In two studies, 7- to 13-year-olds (N = 155, N = 132) were administered tasks thought to assess short-term memory as well as tasks thought to assess working memory. Both exploratory and confirmatory factor analyses distinguished short-term memory tasks from working memory tasks. In addition, performance on working memory tasks was related to word decoding skill but performance on short-term memory tasks was not. Finally, performance on both short-term memory and working memory tasks were associated with age-related increases in processing speed. Results are discussed in relation to models of short-term and working memory.     

Distraction biases working memory for faces

Psychonomic Bulletin & Review - Working memory persists in the face of distraction, yet not without consequence. Previous research has shown that memory for low-level visual features is...     

A visual short-term memory advantage for faces

What determines how much can be stored in visual short-term memory (VSTM)? Studies of VSTM have focused largely on stimulus-based properties such as the number or complexity of the items stored. Recent work also suggests that capacity is severely reduced for items within the same category. However, the importance for VSTM capacity of more qualitative differences in processing for different categories has not been investigated. For example, faces are processed more holistically than other objects. In Experiments 1 and 2, we show that the processing of faces, objects that are crucial socially and for which we possess considerable expertise, overcomes these limitations. More faces can be stored in VSTM than objects from other complex nonface categories. As in prior studies, at short encoding durations we found that capacity for faces was less than that for other categories. However, at longer encoding durations, capacity for faces exceeded that for nonface objects, and this advantage was specific to upright faces. Because inversion reduces holistic processing, the interaction of orientation with VSTM capacity—which occurred for faces but not objects in Experiment 3—suggests that it is holistic processing that confers an advantage for face VSTM when sufficient encoding time is allowed.     

Familiarity enhances visual working memory for faces

Although it is intuitive that familiarity with complex visual objects should aid their preservation in visual working memory (WM), empirical evidence for this is lacking. This study used a conventional change-detection procedure to assess visual WM for unfamiliar and famous faces in healthy adults. Across experiments, faces were upright or inverted and a low- or high-load concurrent verbal WM task was administered to suppress contribution from verbal WM. Even with a high verbal memory load, visual WM performance was significantly better and capacity estimated as significantly greater for famous versus unfamiliar faces. Face inversion abolished this effect. Thus, neither strategic, explicit support from verbal WM nor low-level feature processing easily accounts for the observed benefit of high familiarity for visual WM. These results demonstrate that storage of items in visual WM can be enhanced if robust visual representations of them already exist in long-term memory.     

The role of short-term working memory in mental arithmetic

A series of experiments explored the role of information storage in working memory in performing mental arithmetic. Experiment 1 assessed the strategies people report for solving auditorily presented multidigit problems such as 325 + 46. As expected, all subjects reported breaking down the problems into a series of elementary stages, though there were considerable individual differences with regard to the order of their execution. Strategies of this type necessitate both the temporary storage of information and the mobilization of long-term knowledge. Experiments 2 and 3 examined the effects of delaying the output of individual partial results on calculation accuracy and showed that interim information is forgotten if it is not utilized immediately. Experiment 4 showed that forgetting the initial information is also a source of error and suggested that forgetting increases as a function of the number of calculation stages intervening between initial presentation and subsequent utilization of information. Two simple quantitative models were derived from a general task analysis, one of which assumed a decay process in working storage and the other no decay. The decay model gave a reasonable fit to data from Experiments 2–4, and in doing so it coped appreciably well with the effects of a large variety of task variables (e.g., carrying, the provision of written notes, calculation strategy, output order). The decay model is a tractable analysis of a complex task, and it is suggested that similar analyses may prove fruitful for other problem-solving activities which involve the use of working memory.     

The many faces of self-harm

This paper explores why open dialogue on the subject of erotic transference and countertransference is so difficult and attempts to offer an understanding of these phenomena which might enable counsellors to work more confidently with it. It also briefly examines the author's own research on therapists' thoughts and experiences of erotic transference, seeking to differentiate between inappropriate sexual contact between clients and therapists and the experience of erotic transference in the context of therapy as a reworking of the Oedipal relationship. Case examples illustrating the experience of countertransference within the therapeutic situation and how its presence can act as a help or a hindrance are offered. The paper concludes by examining the need to reflect on the erotic transference in therapeutic work and proposes its usefulness as a therapeutic tool. Suggestions about how the erotic transference can be managed to therapeutic effect are also explored.     

The many faces of interpolation

We present a number of, somewhat unusual, ways of describing what Craig’s interpolation theorem achieves, and use them to identify some open problems and further directions.     

The many faces of amnesia

Results from studies of retrograde amnesia provide much of the evidence for theories of memory consolidation. Retrograde amnesia gradients are often interpreted as revealing the time needed for the formation of long-term memories. The rapid forgetting observed after many amnestic treatments, including protein synthesis inhibitors, and the parallel decay seen in long-term potentiation experiments are presumed to reveal the duration of short-term memory processing. However, there is clear and consistent evidence that the time courses obtained in these amnesia experiments are highly variable within and across experiments and treatments. The evidence is inconsistent with identification of basic temporal properties of memory consolidation. Alternative views include modulation of memory and emphasize the roles that hormones and neurotransmitters have in regulating memory formation. Of related interest, converging lines of evidence suggest that inhibitors of protein synthesis and of other biochemical processes act on modulators of memory formation rather than on mechanisms of memory formation. Based on these findings, memory consolidation and reconsolidation studies might better be identified as memory modulation and "remodulation" studies. Beyond a missing and perhaps unattainable time constant of memory consolidation, some current views of memory consolidation assume that memories, once formed, are generally unmodifiable. It is this perspective that appears to have led to the recent interest in memory reconsolidation. But the view adopted here is that memories are continually malleable, being updated by new experiences and, at the same time, altering the memories of later experiences. Studies of memory remodulation offer promise of understanding the neurobiological bases by which new memories are altered by prior experiences and by which old memories are altered by new experiences.     

The many faces of lying

In this paper the author explores the psychic functions of lying and draws on Glasser's (1979) notions of self-preservative and sadistic violence to identify three selfobject configurations. Each of these is associated with specific anxieties to which the lie offers an apparent solution. The first configuration is sadistic lying. Here the intent is to attack and triumph over the duped other. The lie allows the object to be controlled and humiliated. This gratifies the self by reversing an earlier humiliation. The second and third configurations are both forms of self-preservative lying, where the lie may be best conceived as a symptom of hope (Winnicott, 1985). In the second configuration, the object is felt to be unavailable or inscrutable. The lie may be used to create an attractive self that will elicit the object's love, admiration and concern. In this way, the lie serves to eliminate doubt about the object's intentions towards the self. In the third configuration, the object is felt to be intrusive, and the dyadic relationship is overpowering. Here the lie can represent an attempt to insert a third into the relationship.     

The many faces of autonomy

What does autonomy mean from a moral point of view? Throughout Western history, autonomy has had no less than four different meanings. The first is political: the capacity of old cities and modern states to give themselves their own laws. The second is metaphysical, and was introduced by Kant in the second half of the 18th century. In this meaning, autonomy is understood as an intrinsic characteristic of all rational beings. Opposed to this is the legal meaning, in which actions are called autonomous when performed with due information and competency and without coercion. This last meaning, the most frequently used in bioethics, is primarily legal instead of moral. Is there a proper moral meaning of the word autonomy? If so, this would be a fourth meaning. Acts can only be called moral when they are postconventional (using the terminology coined by Lawrence Kohlberg), inner-directed (as expressed by David Riesman), and responsible (according to Hannah Arendt). Such acts are autonomous in this new, fourth, and to my mind, the only one proper, moral meaning. The goal of ethics cannot be other than forming human beings capable of making autonomous and responsible decisions, and doing so because they think this is their duty and not because of any other nonmoral motivation, like comfort, convenience, or satisfaction. The goal of ethics is to promote postconventional and mature human beings. This was what Socrates tried to do with the young people of Athens. And it is also the objective of every course of ethics and of any process of training.     

Midazolam amnesia and short-term/working memory processes

We examined whether midazolam impairs short-term/working memory processes. We hypothesize that prior dissociations in midazolam's effects on short-term/working memory tasks and episodic memory tasks arise because midazolam has a larger effect on episodic memory processes than on short-term/working memory processes. To examine these issues, .03 mg/kg of participant's bodyweight of midazolam was administered in a double-blind placebo-controlled within-participant design. Performance on the digit span and category generation/recall tasks was examined. The results of Experiment 1 demonstrated that: (1) midazolam impaired performance on the digit span task; (2) midazolam did not impair performance on the category generation task; (3) midazolam impaired performance on the category recall task; and (4) midazolam's effect on category recall was four times as large as its effect on digit span. The results of Experiment 2 demonstrated that midazolam did not impair digit span performance when the digit span task was administered at a later time. These results suggest that midazolam can impair short-term/working memory processes, but these effects are substantially smaller than midazolam's effect on episodic memory processes. Moreover, they demonstrate that conscious awareness of materials during study is not sufficient to produce episodic memory.     

Processing and storage in working memory span

Two experiments are reported that address theoretical assumptions as to the nature of working memory involved in working memory span tasks (Daneman & Carpenter, 1980). Experiment 1 used a version of the sentence span task, and Experiment 2 combined arithmetic verification with recall of presented words. In each experiment, working memory processing span was assessed independently of temporary storage span prior to their combination. Combined task performance under high demand for each component resulted in substantial residual performance for both task elements, particularly in Experiment 2. The results do not challenge the utility of the sentence span task as a measure of on-line cognition, but they raise concerns as to how resource might be allocated to processing and storage elements of the task within a single flexible resource pool, or between different resources of a multiple component working memory system. Although both models lack predictive power regarding resource allocation in these tasks, the multiple resource model appears to offer the better account.     

The many faces of configural processing

Adults' expertise in recognizing faces has been attributed to configural processing. We distinguish three types of configural processing: detecting the first-order relations that define faces (i.e. two eyes above a nose and mouth), holistic processing (glueing the features together into a gestalt), and processing second-order relations (i.e. the spacing among features). We provide evidence for their separability based on behavioral marker tasks, their sensitivity to experimental manipulations, and their patterns of development. We note that inversion affects each type of configural processing, not just sensitivity to second-order relations, and we review evidence on whether configural processing is unique to faces.     

The storage of physical and name properties in short-term visual memory

Two experiments investigated the hypothesis that short-term visual memory is based primarily on physical features of the visual input. Subjects were required to recall visually presented figures or the names of those figures presented either visually or aurally at a number of different retention intervals. Subjects shadowed words during the retention interval presented aurally in Experiment I and visually in Experiment II. In both experiments, figures were recalled better than names and no differences in recall of names were found due to presentation modality. Recall of both names conditions showed a steady decline across retention intervals whereas recall of figures remained at a relatively high level. These findings were interpreted as providing further support for the existence of short-term visual memory not subject to auditory recoding and based primarily on physical features of the input. It was suggested that such visual memory is limited in capacity so that input exceeding this capacity is recoded into an auditory-verbal-linguistic form.     

On the independence of short-term memory and working memory in cognitive development

We report some experiments that were concerned with the now familiar hypothesis that short-term memory and information processing draw upon a common pool of scarce resources. The results of two series of experiments were more consistent with the hypothesis that the resources that support short-term memory and information processing do not overlap and develop independently of each other. In Experiments 1–4, children's performance on four reasoning problems (class inclusion, conservation, probability judgment, and transitive inference) was found to be stochastically independent of their short-term memory for the critical background facts on these problems. Age changes in reasoning and short-term memory also proved to be independent. It was found in the second series of experiments that certain manipulations which affect the accuracy of children's reasoning do not affect short-term memory, and conversely. In Experiments 5–7, manipulations that affected the difficulty of information processing on class-inclusion and transitivity tasks did not affect short-term memory on these same tasks. In Experiments 8 and 9, manipulations that affected short-term retention of the background facts on conservation and probability-judgment tasks did not affect reasoning on these same tasks.     

Neural effects of short-term training on working memory

Working memory training has been the focus of intense research interest. Despite accumulating behavioral work, knowledge about the neural mechanisms underlying training effects is scarce. Here, we show that 7 days of training on an n-back task led to substantial performance improvements in the trained task; furthermore, the experimental group showed cross-modal transfer, as compared with an active control group. In addition, there were two neural effects that emerged as a function of training: first, increased perfusion during task performance in selected regions, reflecting a neural response to cope with high task demand; second, increased blood flow at rest in regions where training effects were apparent. We also found that perfusion at rest was correlated with task proficiency, probably reflecting an improved neural readiness to perform. Our findings are discussed within the context of the available neuroimaging literature on n-back training.     

Attention and information storage in visual short-term memory

Schioldborg, P. Attention and information storage in visual short-term memory. Scand. J. Psychol., 1973, 14, 1–3.- Information retrieval from STM was examined with Sperling's (1960) method. Of nine letters displayed in rows of three, the number of letters correctly reported from each row differed significantly, the mean being 2.4, 2.2, and 1.6 letters for the middle, upper, and lower row, respectively. By increasing exposure time, number of correctly reported letters increased for each row at equal rate. However, by increasing the delay period of the selection signal, number of letters decreased at different rates, the reduction being 48%, 24%, and 10% for the lower, upper, and middle row respectively. The results are assumed to reflect differences in the initial attention level for the individual item; the smaller this level, the lower the level of information processing and the faster the erasure from STM.