It is well established that digit span in native Chinese speakers is atypically high. This is commonly attributed to a capacity for more rapid subvocal rehearsal for that group. We explored this hypothesis by testing a group of... more
It is well established that digit span in native Chinese speakers is atypically high. This is commonly attributed to a capacity for more rapid subvocal rehearsal for that group. We explored this hypothesis by testing a group of English-speaking native Mandarin speakers on digit span and word span in both Mandarin and English, together with a measure of speed of articulation for each. When compared to the performance of native English speakers, the Mandarin group proved to be superior on both digit and word spans while predictably having lower spans in English. This suggests that the Mandarin advantage is not limited to digits. Speed of rehearsal correlated with span performance across materials. However, this correlation was more pronounced for English speakers than for any of the Chinese measures. Further analysis suggested that speed of rehearsal did not provide an adequate account of differences between Mandarin and English spans or for the advantage of digits over words. Possibl...
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Immediate serial recall of verbal material is highly sensitive to impairment attributable to phonological similarity. Although this has traditionally been interpreted as a within-sequence similarity effect, Engle (2007) proposed an... more
Immediate serial recall of verbal material is highly sensitive to impairment attributable to phonological similarity. Although this has traditionally been interpreted as a within-sequence similarity effect, Engle (2007) proposed an interpretation based on interference from prior sequences, a phenomenon analogous to that found in the Peterson short-term memory (STM) task. We use the method of serial reconstruction to test this in an experiment contrasting the standard paradigm in which successive sequences are drawn from the same set of phonologically similar or dissimilar words and one in which the vowel sound on which similarity is based is switched from trial to trial, a manipulation analogous to that producing release from PI in the Peterson task. A substantial similarity effect occurs under both conditions although there is a small advantage from switching across similar sequences. There is, however, no evidence for the suggestion that the similarity effect will be absent from the very first sequence tested. Our results support the within-sequence similarity rather than a between-list PI interpretation. Reasons for the contrast with the classic Peterson short-term forgetting task are briefly discussed.
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In visual working memory tasks, memory for an item is enhanced if participants are told that the item is relatively more valuable than others presented within the same trial. Experiment 1 explored whether these probe value boosts (termed... more
In visual working memory tasks, memory for an item is enhanced if participants are told that the item is relatively more valuable than others presented within the same trial. Experiment 1 explored whether these probe value boosts (termed prioritization effects in previous literature) are affected by probe frequency (i.e., how often the more valuable item is tested). Participants were presented with four colored shapes sequentially and asked to recall the color of one probed item following a delay. They were informed that the first item was more valuable (differential probe value) or as valuable as the other items (equal probe value), and that this item would be tested more frequently (differential probe frequency) or as frequently (equal probe frequency) as the other items. Probe value and probe frequency boosts were observed at the first position, though both were accompanied by costs to other items. Probe value and probe frequency boosts were additive, suggesting the manipulations...
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Recent research has demonstrated that, when instructed to prioritize a serial position in visual working memory (WM), adults are able to boost performance for this selected item, at a cost to nonprioritized items (e.g., Hu, Hitch,... more
Recent research has demonstrated that, when instructed to prioritize a serial position in visual working memory (WM), adults are able to boost performance for this selected item, at a cost to nonprioritized items (e.g., Hu, Hitch, Baddeley, Zhang, & Allen, 2014). While executive control appears to play an important role in this ability, the increased likelihood of recalling the most recently presented item (i.e., the recency effect) is relatively automatic, possibly driven by perceptual mechanisms. In 3 Experiments 7 to 10 year-old's ability to prioritize items in WM was investigated using a sequential visual task (total N = 208). The relationship between individual differences in WM and performance on the experimental task was also explored. Participants were unable to prioritize the first (Experiments 1 and 2) or final (Experiment 3) item in a 3-item sequence, while large recency effects for the final item were consistently observed across all experiments. The absence of a pri...
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A number of studies suggest an important role for the hippocampus in tasks involving visuospatial or relational working memory. We test the generality of this proposal across tasks using a battery designed to investigate the various... more
A number of studies suggest an important role for the hippocampus in tasks involving visuospatial or relational working memory. We test the generality of this proposal across tasks using a battery designed to investigate the various components of working memory, studying the working memory performance of Jon, who shows a bilateral reduction in hippocampal volume of approximately 50%, comparing him to a group of 48 college students. We measure performance on four complex working memory span measures based on combining visuospatial and verbal storage with visuospatial or verbal concurrent processing as well as measuring Jon's ability to carry out the component storage and processing aspects of these tasks. Jon performed at a consistently high level across our range of tasks. Possible reasons for the apparent disparity between our own findings and earlier studies showing a hippocampal deficit are discussed in terms of both the potential differences in the demands placed on relational memory and of the proposed distinction between egocentric and allocentric visuospatial processing.
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We report the performance in four recognition memory experiments of Jon, a young adult with early-onset developmental amnesia whose episodic memory is gravely impaired in tests of recall, but seems relatively preserved in tests of... more
We report the performance in four recognition memory experiments of Jon, a young adult with early-onset developmental amnesia whose episodic memory is gravely impaired in tests of recall, but seems relatively preserved in tests of recognition, and who has developed normal levels of performance in tests of intelligence and general knowledge. Jon's recognition performance was enhanced by deeper levels of processing in comparing a more meaningful study task with a less meaningful one, but not by task enactment in comparing performance of an action with reading an action phrase. Both of these variables normally enhance episodic remembering, which Jon claimed to experience. But Jon was unable to support that claim by recollecting what it was that he remembered. Taken altogether, the findings strongly imply that Jon's recognition performance entailed little genuine episodic remembering and that the levels-of-processing effects in Jon reflected semantic, not episodic, memory.
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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... more
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 several reasons to question these proposals. We conclude with a brief discussion of the implications of the longevity of the modal model for styles of theorising in cognitive psychology.
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Recent research has indicated that visual working memory capacity for unidimensional items might be boosted by focusing on all presented items, as opposed to a subset of them. However, it is not clear whether the same outcomes would be... more
Recent research has indicated that visual working memory capacity for unidimensional items might be boosted by focusing on all presented items, as opposed to a subset of them. However, it is not clear whether the same outcomes would be observed if more complex items were used which require feature binding, a potentially more demanding task. The current experiments, therefore, examined the effects of encoding strategy using multidimensional items in tasks that required feature binding. Effects were explored across a range of different age groups (Experiment 1) and task conditions (Experiment 2). In both experiments, participants performed significantly better when focusing on a subset of items, regardless of age or methodological variations, suggesting this is the optimal strategy to use when several multidimensional items are presented and binding is required. Implications for task interpretation and visual working memory function are discussed.
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The contents of visual working memory are likely to reflect the influence of both executive control resources and information present in the environment. We investigated whether executive attention is critical in the ability to exclude... more
The contents of visual working memory are likely to reflect the influence of both executive control resources and information present in the environment. We investigated whether executive attention is critical in the ability to exclude unwanted stimuli by introducing concurrent potentially distracting irrelevant items to a visual working memory paradigm, and manipulating executive load using simple or more demanding secondary verbal tasks. Across 7 experiments varying in presentation format, timing, stimulus set, and distractor number, we observed clear disruptive effects of executive load and visual distraction, but relatively minimal evidence supporting an interactive relationship between these factors. These findings are in line with recent evidence using delay-based interference, and suggest that different forms of attentional selection operate relatively independently in visual working memory.
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Previous research on memory for a short sequence of visual stimuli indicates that access to the focus of attention (FoA) can be achieved in either of two ways. The first is automatic and is indexed by the recency effect, the enhanced... more
Previous research on memory for a short sequence of visual stimuli indicates that access to the focus of attention (FoA) can be achieved in either of two ways. The first is automatic and is indexed by the recency effect, the enhanced retention of the final item. The second is strategic and based on instructions to prioritize items differentially, a process that draws on executive capacity and boosts retention of information deemed important. In both cases, the increased level of retention can be selectively reduced by presenting a poststimulus distractor (or suffix). We manipulated these variables across three experiments. Experiment 1 generalized previous evidence that prioritizing a single item enhances its retention and increases its vulnerability to interference from a poststimulus suffix. A second experiment showed that the enhancement from prioritizing one or two items comes at a cost to the recency effect. A third experiment showed that prioritizing two items renders memory for both vulnerable to interference from an irrelevant suffix. The results suggest that some but not all items in working memory compete to occupy a narrow FoA and that this competition is determined by a combination of perceptually driven recency and internal executive control.
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Neath (2000) presents a useful overview of the evidence to be explained by any model of the effects of irrelevant speech on immediate serial memory and proposes a model accompanied by computational simulation. While his review is in... more
Neath (2000) presents a useful overview of the evidence to be explained by any model of the effects of irrelevant speech on immediate serial memory and proposes a model accompanied by computational simulation. While his review is in general accurate, it is limited in its explanation of the crucial characteristics of the disrupting sounds. It also neglects strategic issues, particularly the tendency for subjects to switch strategy as list length increases. As a result, his model fails to account for the absence of an interaction between irrelevant speech and acoustic similarity for lists of span length. Points of issue between Neath's feature hypothesis and the phonological loop interpretation are outlined, and the contribution of his computational simulation is discussed.
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Research Interests: Cognition, Tropical Medicine, Adolescent, Tanzania, Tropical medicine (Health Sciences), and 15 moreHumans, Child, Female, Animals, Male, Reaction Time, Urine, Nutritional Status, School Children, Public health systems and services research, Feces, Short Term Memory, Educational Status, Cognition disorders, and Psychomotor Performance
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Levinger & Clarke (1961) found that subjects tended to forget more word associations to emotional rather than neutral words. Kline (1981) regarded this study as providing 'irrefutable evidence for the Freudian concept of... more
Levinger & Clarke (1961) found that subjects tended to forget more word associations to emotional rather than neutral words. Kline (1981) regarded this study as providing 'irrefutable evidence for the Freudian concept of repression'. On the other hand, results from Kleinsmith & Kaplan (1964) suggested that this effect may reverse after a delay. The present study attempted to replicate Levinger & Clark's result using stimulus words balanced for concreteness and frequency. In addition, recall was tested immediately and after a delay. Associations to emotional material were more poorly recalled immediately than associations to material which was low in emotional valence, but tended to be better recalled a month later. There were no differences in recall of pleasant versus unpleasant material. Results do not support the repression hypothesis, in that emotional material becomes more memorable over time. Moreover, repression should differentially apply to unpleasant rather than pleasant material but no such differences were found.
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In a sample of 60 schizophrenic patients encompassing all grades of severity and chronicity memory impairment was found to be prevalent, often substantial, and disproportionate to the overall level of intellectual impairment. The deficits... more
In a sample of 60 schizophrenic patients encompassing all grades of severity and chronicity memory impairment was found to be prevalent, often substantial, and disproportionate to the overall level of intellectual impairment. The deficits were not easily attributable to poor cooperation, attention or motivation; nor were they related to neuroleptic or anticholinergic medication. Memory impairment was significantly associated with severity and chronicity of illness and also with negative symptoms and formal thought disorder. There was evidence from the sample as a whole, and from a more detailed examination of five patients with relatively isolated deficits, that schizophrenic memory impairment conformed to the pattern seen in the classical amnesic syndrome. Additionally, there was preliminary evidence for a marked deficit in semantic memory.
Research Interests: Psychology, Psychometrics, Schizophrenia, Psychological Medicine, Humans, and 12 moreChronic Disease, Female, Male, Aged, Middle Aged, Adult, Public health systems and services research, Short Term Memory, Neurosciences, Verbal Learning, Psychiatric Status Rating Scales, and Neuropsychological Tests
Memory impairment is not usually considered to form part of the clinical picture of schizophrenia, except perhaps in severely deteriorated patients. In a survey of 60 patients encompassing all grades of severity and chronicity poor memory... more
Memory impairment is not usually considered to form part of the clinical picture of schizophrenia, except perhaps in severely deteriorated patients. In a survey of 60 patients encompassing all grades of severity and chronicity poor memory performance was found to be common, sometimes substantial, and disproportionately pronounced compared to the degree of general intellectual impairment. Although associated with severity and chronicity of illness, impaired memory was by no means confined to old, institutionalized, or markedly deteriorated patients. The pattern of deficit appeared to resemble that of the classic amnesic syndrome rather than that seen in Alzheimer-type dementia.
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Individuals infected with Human Immunodeficiency Virus (HIV) and having cognitive impairment have been described as having slow mentation. Data supporting this proposition come from a variety of sources, including... more
Individuals infected with Human Immunodeficiency Virus (HIV) and having cognitive impairment have been described as having slow mentation. Data supporting this proposition come from a variety of sources, including Sternberg's (1966) item recognition memory task. The procedure nominally provides an index of speed of mental operations, independent from input/output demands. However, since the original use of this procedure in the 1960s, advances in cognitive psychology have revealed many of its limitations. The purpose of the present study was to examine the psychometric characteristics of this task. Each participant performed the Sternberg item recognition task twice, 6 mo apart. The stability of the estimate of the slope of regression equations and for zero intercept ranged from excellent (r = .87) to poor (r = .30), and the data from many individual subjects could not be reliably modelled using multiple linear regression techniques. These data, as well as those from previous research, demonstrate the limited practical use of this task in clinical samples. Furthermore, as cognitive psychological theory has advanced in the past 30 yr, the conceptual underpinnings of the procedure have essentially evaporated.
Research Interests: Psychometrics, Schizophrenia, Medication Adherence, Adolescent, Humans, and 20 moreUnited States, Female, Male, Reaction Time, Regression Analysis, Missouri, Young Adult, The, Medicaid, Middle Aged, Adult, Time Factors, AIDS Dementia Complex, Reference Values, Delayed-Action Preparations, Cognition disorders, Injections, Cohort Studies, Psychomotor Performance, and Neuropsychological Tests
The deficits of attention contribute significantly to the clinical picture of functional disability seen in schizophrenia, but there is no consensus as to whether this cognitive function can be fractionated to allow further... more
The deficits of attention contribute significantly to the clinical picture of functional disability seen in schizophrenia, but there is no consensus as to whether this cognitive function can be fractionated to allow further characterisation of the impairment. We examined fifteen patients with chronic schizophrenia and fifteen controls using paired tasks designed to measure four hypothetical aspects of attentional control: the ability to focus attention, to resist distraction, to shift attention, and to divide attention. The group with schizophrenia showed a significant improvement in accuracy on a digit span repetition task when a simultaneous box-crossing task was added (divided attention condition). Although the patient group showed impaired performance across nearly all of the tasks, they were not disproportionately impaired during the task conditions assumed to demand greater attention. These results suggest that the aspects of attention and executive function under study are not significantly affected by schizophrenia and indicate the need for further characterisation of the impairment usually reported using conventional tests of attention on those with schizophrenia.
Research Interests: Schizophrenia, Cognition, Attention, Working Memory, Attentional Control, and 20 moreExecutive Function, Problem Solving, Divided Attention, Humans, Models, Chronic Disease, Female, Male, Reaction Time, Digit span, Middle Aged, Adult, Cognitive Models, Cognitive Function, Cognitive Model, Psychiatric, Central Executive, Cognition disorders, Functional Disability, and Psychomotor Performance
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Cognitive neuropsychiatry occupies the comparatively neglected research region that lies between neurology, psychiatry, and cognitive psychology. Reasons for this neglect are discussed, together with arguments as to why it may be timely... more
Cognitive neuropsychiatry occupies the comparatively neglected research region that lies between neurology, psychiatry, and cognitive psychology. Reasons for this neglect are discussed, together with arguments as to why it may be timely to focus on this intellectual no man's land.
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... PAUL WB ATKINS University of New South Wales ALAN D. BADDELEY University of Bristol ADDRESS FOR CORRESPONDENCE Paul Atkins, School of Psychology, University of New South Wales, Kensington, Sydney, NSW 2052, Australia. Email:... more
... PAUL WB ATKINS University of New South Wales ALAN D. BADDELEY University of Bristol ADDRESS FOR CORRESPONDENCE Paul Atkins, School of Psychology, University of New South Wales, Kensington, Sydney, NSW 2052, Australia. Email: p.atkins@unsw.edu.au ...