The role of memory representation in the vigilance decrement

PubMed Central

CAGGIANO, DANIEL M.; PARASURAMAN, RAJA

2005-01-01

Working memory load is critically important for the overall level of performance on vigilance tasks. However, its role in a key aspect of vigilance—sensitivity decrement over time—is unclear. We used a dual-task procedure in which either a spatial or a nonspatial working memory task was performed simultaneously with a spatial vigilance task for 20 min. Sensitivity in the vigilance task declined over time when the concurrent task involved spatial working memory. In contrast, there was no sensitivity decrement with a nonspatial working memory task. The results provide the first evidence of a specific role for working memory representation in vigilance decrement. The findings are also consistent with a multiple resource theory in which separate resources for memory representation and cognitive control operations are differentially susceptible to depletion over time, depending on the demands of the task at hand. PMID:15732706

Working Memory Capacity and Reading Skill Moderate the Effectiveness of Strategy Training in Learning from Hypertext

ERIC Educational Resources Information Center

Naumann, Johannes; Richter, Tobias; Christmann, Ursula; Groeben, Norbert

2008-01-01

Cognitive and metacognitive strategies are particularly important for learning with hypertext. The effectiveness of strategy training, however, depends on available working memory resources. Thus, especially learners high on working memory capacity can profit from strategy training, while learners low on working memory capacity might easily be…

On the role of working memory in spatial contextual cueing.

PubMed

Travis, Susan L; Mattingley, Jason B; Dux, Paul E

2013-01-01

The human visual system receives more information than can be consciously processed. To overcome this capacity limit, we employ attentional mechanisms to prioritize task-relevant (target) information over less relevant (distractor) information. Regularities in the environment can facilitate the allocation of attention, as demonstrated by the spatial contextual cueing paradigm. When observers are exposed repeatedly to a scene and invariant distractor information, learning from earlier exposures enhances the search for the target. Here, we investigated whether spatial contextual cueing draws on spatial working memory resources and, if so, at what level of processing working memory load has its effect. Participants performed 2 tasks concurrently: a visual search task, in which the spatial configuration of some search arrays occasionally repeated, and a spatial working memory task. Increases in working memory load significantly impaired contextual learning. These findings indicate that spatial contextual cueing utilizes working memory resources.

Shared processing in multiple object tracking and visual working memory in the absence of response order and task order confounds

PubMed Central

Howe, Piers D. L.

2017-01-01

To understand how the visual system represents multiple moving objects and how those representations contribute to tracking, it is essential that we understand how the processes of attention and working memory interact. In the work described here we present an investigation of that interaction via a series of tracking and working memory dual-task experiments. Previously, it has been argued that tracking is resistant to disruption by a concurrent working memory task and that any apparent disruption is in fact due to observers making a response to the working memory task, rather than due to competition for shared resources. Contrary to this, in our experiments we find that when task order and response order confounds are avoided, all participants show a similar decrease in both tracking and working memory performance. However, if task and response order confounds are not adequately controlled for we find substantial individual differences, which could explain the previous conflicting reports on this topic. Our results provide clear evidence that tracking and working memory tasks share processing resources. PMID:28410383

Shared processing in multiple object tracking and visual working memory in the absence of response order and task order confounds.

PubMed

Lapierre, Mark D; Cropper, Simon J; Howe, Piers D L

2017-01-01

To understand how the visual system represents multiple moving objects and how those representations contribute to tracking, it is essential that we understand how the processes of attention and working memory interact. In the work described here we present an investigation of that interaction via a series of tracking and working memory dual-task experiments. Previously, it has been argued that tracking is resistant to disruption by a concurrent working memory task and that any apparent disruption is in fact due to observers making a response to the working memory task, rather than due to competition for shared resources. Contrary to this, in our experiments we find that when task order and response order confounds are avoided, all participants show a similar decrease in both tracking and working memory performance. However, if task and response order confounds are not adequately controlled for we find substantial individual differences, which could explain the previous conflicting reports on this topic. Our results provide clear evidence that tracking and working memory tasks share processing resources.

Flexible attention allocation to visual and auditory working memory tasks: manipulating reward induces a trade-off.

PubMed

Morey, Candice Coker; Cowan, Nelson; Morey, Richard D; Rouder, Jeffery N

2011-02-01

Prominent roles for general attention resources are posited in many models of working memory, but the manner in which these can be allocated differs between models or is not sufficiently specified. We varied the payoffs for correct responses in two temporally-overlapping recognition tasks, a visual array comparison task and a tone sequence comparison task. In the critical conditions, an increase in reward for one task corresponded to a decrease in reward for the concurrent task, but memory load remained constant. Our results show patterns of interference consistent with a trade-off between the tasks, suggesting that a shared resource can be flexibly divided, rather than only fully allotted to either of the tasks. Our findings support a role for a domain-general resource in models of working memory, and furthermore suggest that this resource is flexibly divisible.

Influence of Response Prepotency Strength, General Working Memory Resources, and Specific Working Memory Load on the Ability to Inhibit Predominant Responses: A Comparison of Young and Elderly Participants

ERIC Educational Resources Information Center

Grandjean, Julien; Collette, Fabienne

2011-01-01

One conception of inhibitory functioning suggests that the ability to successfully inhibit a predominant response depends mainly on the strength of that response, the general functioning of working memory processes, and the working memory demand of the task (Roberts, Hager, & Heron, 1994). The proposal that inhibition and functional working memory…

Attention allocation: Relationships to general working memory or specific language processing.

PubMed

Archibald, Lisa M D; Levee, Tyler; Olino, Thomas

2015-11-01

Attention allocation, updating working memory, and language processing are interdependent cognitive tasks related to the focused direction of limited resources, refreshing and substituting information in the current focus of attention, and receiving/sending verbal communication, respectively. The current study systematically examined the relationship among executive attention, working memory executive skills, and language abilities while adjusting for individual differences in short-term memory. School-age children completed a selective attention task requiring them to recall whether a presented shape was in the same place as a previous target shape shown in an array imposing a low or high working memory load. Results revealed a selective attention cost when working above but not within memory span capacity. Measures of general working memory were positively related to overall task performance, whereas language abilities were related to response time. In particular, higher language skills were associated with faster responses under low load conditions. These findings suggest that attentional control and storage demands have an additive impact on working memory resources but provide only limited evidence for a domain-general mechanism in language learning. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

Contrasting single and multi-component working-memory systems in dual tasking.

PubMed

Nijboer, Menno; Borst, Jelmer; van Rijn, Hedderik; Taatgen, Niels

2016-05-01

Working memory can be a major source of interference in dual tasking. However, there is no consensus on whether this interference is the result of a single working memory bottleneck, or of interactions between different working memory components that together form a complete working-memory system. We report a behavioral and an fMRI dataset in which working memory requirements are manipulated during multitasking. We show that a computational cognitive model that assumes a distributed version of working memory accounts for both behavioral and neuroimaging data better than a model that takes a more centralized approach. The model's working memory consists of an attentional focus, declarative memory, and a subvocalized rehearsal mechanism. Thus, the data and model favor an account where working memory interference in dual tasking is the result of interactions between different resources that together form a working-memory system. Copyright © 2016 Elsevier Inc. All rights reserved.

Adult age differences in the storage of information in working memory.

PubMed

Foos, P W; Wright, L

1992-01-01

The performance of 97 young and 91 old persons were compared to determine if a deficiency in working memory resources for processing, storage, or allocation could be detected. Persons simultaneously performed a storage and one of two processing tasks while instructed to allocate resources to processing, storage, or both tasks. The storage task involved remembering the names of one, three, or five persons. Processing tasks involved solving addition problems presented on flashcards or answering common knowledge questions. Results showed increased age differences on the storage task as demands for resources increased but no differences on processing tasks. Individuals seemed unable to allocate resources as instructed. A comparison of young-old and old-old groups showed the same results as those obtained comparing young and old groups and support the hypothesis of a deficiency of storage, but not processing, resources in working memory for old, especially old-old, adults.

Extending Cognitive Load Theory to Incorporate Working Memory Resource Depletion: Evidence from the Spacing Effect

ERIC Educational Resources Information Center

Chen, Ouhao; Castro-Alonso, Juan C.; Paas, Fred; Sweller, John

2018-01-01

Depletion of limited working memory resources may occur following extensive mental effort resulting in decreased performance compared to conditions requiring less extensive mental effort. This "depletion effect" can be incorporated into cognitive load theory that is concerned with using the properties of human cognitive architecture,…

Selection and Storage of Perceptual Groups Is Constrained by a Discrete Resource in Working Memory

ERIC Educational Resources Information Center

Anderson, David E.; Vogel, Edward K.; Awh, Edward

2013-01-01

Perceptual grouping can lead observers to perceive a multielement scene as a smaller number of hierarchical units. Past work has shown that grouping enables more elements to be stored in visual working memory (WM). Although this may appear to contradict so-called discrete resource models that argue for fixed item limits in WM storage, it is also…

Changing concepts of working memory

PubMed Central

Ma, Wei Ji; Husain, Masud; Bays, Paul M

2014-01-01

Working memory is widely considered to be limited in capacity, holding a fixed, small number of items, such as Miller's ‘magical number’ seven or Cowan's four. It has recently been proposed that working memory might better be conceptualized as a limited resource that is distributed flexibly among all items to be maintained in memory. According to this view, the quality rather than the quantity of working memory representations determines performance. Here we consider behavioral and emerging neural evidence for this proposal. PMID:24569831

Visuospatial Working Memory Capacity Predicts Physiological Arousal in a Narrative Task.

PubMed

Smithson, Lisa; Nicoladis, Elena

2016-06-01

Physiological arousal that occurs during narrative production is thought to reflect emotional processing and cognitive effort (Bar-Haim et al. in Dev Psychobiol 44:238-249, 2004). The purpose of this study was to determine whether individual differences in visuospatial working memory and/or verbal working memory capacity predict physiological arousal in a narrative task. Visuospatial working memory was a significant predictor of skin conductance level (SCL); verbal working memory was not. When visuospatial working memory interference was imposed, visuospatial working memory was no longer a significant predictor of SCL. Visuospatial interference also resulted in a significant reduction in SCL. Furthermore, listener ratings of narrative quality were contingent upon the visuospatial working memory resources of the narrator. Potential implications for educators and clinical practitioners are discussed.

Do the Contents of Visual Working Memory Automatically Influence Attentional Selection during Visual Search?

ERIC Educational Resources Information Center

Woodman, Geoffrey F.; Luck, Steven J.

2007-01-01

In many theories of cognition, researchers propose that working memory and perception operate interactively. For example, in previous studies researchers have suggested that sensory inputs matching the contents of working memory will have an automatic advantage in the competition for processing resources. The authors tested this hypothesis by…

Working Memory, Motivation, and Teacher-Initiated Learning

ERIC Educational Resources Information Center

Brooks, David W.; Shell, Duane F.

2006-01-01

Working memory is where we "think" as we learn. A notion that emerges as a synthesis from several threads in the research literatures of cognition, motivation, and connectionism is that motivation in learning is the process whereby working memory resource allocation is instigated and sustained. This paper reviews much literature on motivation and…

Statistical Learning Induces Discrete Shifts in the Allocation of Working Memory Resources

ERIC Educational Resources Information Center

Umemoto, Akina; Scolari, Miranda; Vogel, Edward K.; Awh, Edward

2010-01-01

Observers can voluntarily select which items are encoded into working memory, and the efficiency of this process strongly predicts memory capacity. Nevertheless, the present work suggests that voluntary intentions do not exclusively determine what is encoded into this online workspace. Observers indicated whether any items from a briefly stored…

Mental Capacity and Working Memory in Chemistry: Algorithmic "versus" Open-Ended Problem Solving

ERIC Educational Resources Information Center

St Clair-Thompson, Helen; Overton, Tina; Bugler, Myfanwy

2012-01-01

Previous research has revealed that problem solving and attainment in chemistry are constrained by mental capacity and working memory. However, the terms mental capacity and working memory come from different theories of cognitive resources, and are assessed using different tasks. The current study examined the relationships between mental…

Complex Sentence Comprehension and Working Memory in Children With Specific Language Impairment

PubMed Central

Montgomery, James W.; Evans, Julia L.

2015-01-01

Purpose This study investigated the association of 2 mechanisms of working memory (phonological short-term memory [PSTM], attentional resource capacity/allocation) with the sentence comprehension of school-age children with specific language impairment (SLI) and 2 groups of control children. Method Twenty-four children with SLI, 18 age-matched (CA) children, and 16 language- and memory-matched (LMM) children completed a nonword repetition task (PSTM), the competing language processing task (CLPT; resource capacity/allocation), and a sentence comprehension task comprising complex and simple sentences. Results (1) The SLI group performed worse than the CA group on each memory task; (2) all 3 groups showed comparable simple sentence comprehension, but for complex sentences, the SLI and LMM groups performed worse than the CA group; (3) for the SLI group, (a) CLPT correlated with complex sentence comprehension, and (b) nonword repetition correlated with simple sentence comprehension; (4) for CA children, neither memory variable correlated with either sentence type; and (5) for LMM children, only CLPT correlated with complex sentences. Conclusions Comprehension of both complex and simple grammar by school-age children with SLI is a mentally demanding activity, requiring significant working memory resources. PMID:18723601

Precision of working memory for visual motion sequences and transparent motion surfaces

PubMed Central

Zokaei, Nahid; Gorgoraptis, Nikos; Bahrami, Bahador; Bays, Paul M; Husain, Masud

2012-01-01

Recent studies investigating working memory for location, colour and orientation support a dynamic resource model. We examined whether this might also apply to motion, using random dot kinematograms (RDKs) presented sequentially or simultaneously. Mean precision for motion direction declined as sequence length increased, with precision being lower for earlier RDKs. Two alternative models of working memory were compared specifically to distinguish between the contributions of different sources of error that corrupt memory (Zhang & Luck (2008) vs. Bays et al (2009)). The latter provided a significantly better fit for the data, revealing that decrease in memory precision for earlier items is explained by an increase in interference from other items in a sequence, rather than random guessing or a temporal decay of information. Misbinding feature attributes is an important source of error in working memory. Precision of memory for motion direction decreased when two RDKs were presented simultaneously as transparent surfaces, compared to sequential RDKs. However, precision was enhanced when one motion surface was prioritized, demonstrating that selective attention can improve recall precision. These results are consistent with a resource model that can be used as a general conceptual framework for understanding working memory across a range of visual features. PMID:22135378

Is the Binding of Visual Features in Working Memory Resource-Demanding?

ERIC Educational Resources Information Center

Allen, Richard J.; Baddeley, Alan D.; Hitch, Graham J.

2006-01-01

The episodic buffer component of working memory is assumed to play a role in the binding of features into chunks. A series of experiments compared memory for arrays of colors or shapes with memory for bound combinations of these features. Demanding concurrent verbal tasks were used to investigate the role of general attentional processes,…

Post-encoding control of working memory enhances processing of relevant information in rhesus monkeys (Macaca mulatta).

PubMed

Brady, Ryan J; Hampton, Robert R

2018-06-01

Working memory is a system by which a limited amount of information can be kept available for processing after the cessation of sensory input. Because working memory resources are limited, it is adaptive to focus processing on the most relevant information. We used a retro-cue paradigm to determine the extent to which monkey working memory possesses control mechanisms that focus processing on the most relevant representations. Monkeys saw a sample array of images, and shortly after the array disappeared, they were visually cued to a location that had been occupied by one of the sample images. The cue indicated which image should be remembered for the upcoming recognition test. By determining whether the monkeys were more accurate and quicker to respond to cued images compared to un-cued images, we tested the hypothesis that monkey working memory focuses processing on relevant information. We found a memory benefit for the cued image in terms of accuracy and retrieval speed with a memory load of two images. With a memory load of three images, we found a benefit in retrieval speed but only after shortening the onset latency of the retro-cue. Our results demonstrate previously unknown flexibility in the cognitive control of memory in monkeys, suggesting that control mechanisms in working memory likely evolved in a common ancestor of humans and monkeys more than 32 million years ago. Future work should be aimed at understanding the interaction between memory load and the ability to control memory resources, and the role of working memory control in generating differences in cognitive capacity among primates. Copyright © 2018 Elsevier B.V. All rights reserved.

Word-Decoding Skill Interacts with Working Memory Capacity to Influence Inference Generation during Reading

ERIC Educational Resources Information Center

Hamilton, Stephen; Freed, Erin; Long, Debra L.

2016-01-01

The aim of this study was to examine predictions derived from a proposal about the relation between word-decoding skill and working memory capacity, called verbal efficiency theory. The theory states that poor word representations and slow decoding processes consume resources in working memory that would otherwise be used to execute high-level…

The costs of changing an intended action: movement planning, but not execution, interferes with verbal working memory.

PubMed

Spiegel, M A; Koester, D; Weigelt, M; Schack, T

2012-02-16

How much cognitive effort does it take to change a movement plan? In previous studies, it has been shown that humans plan and represent actions in advance, but it remains unclear whether or not action planning and verbal working memory share cognitive resources. Using a novel experimental paradigm, we combined in two experiments a grasp-to-place task with a verbal working memory task. Participants planned a placing movement toward one of two target positions and subsequently encoded and maintained visually presented letters. Both experiments revealed that re-planning the intended action reduced letter recall performance; execution time, however, was not influenced by action modifications. The results of Experiment 2 suggest that the action's interference with verbal working memory arose during the planning rather than the execution phase of the movement. Together, our results strongly suggest that movement planning and verbal working memory share common cognitive resources. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Post-traumatic stress disorder is associated with limited executive resources in a working memory task

PubMed Central

Honzel, Nikki; Justus, Timothy; Swick, Diane

2015-01-01

Patients with post-traumatic stress disorder (PTSD) can show declines in working memory. A dual-task design was used to determine if these impairments are linked to executive control limitations. Participants performed a Sternberg memory task with either one or four letters. In the dual-task condition, the maintenance period was filled with an arrow flanker task. PTSD patients were less accurate on the working memory task than controls, especially in the dual-task condition. In the single-task condition, both groups showed similar patterns of brain potentials from 300–500 ms when discriminating old and new probes. However, when taxed with an additional task, the event-related potentials (ERPs) of the PTSD group no longer differentiated old and new probes. In contrast, interference resolution processes in both the single- and dual-task conditions of the flanker were intact. The lack of differentiation in the ERPs reflects impaired working memory performance under more difficult dual-task conditions. Exacerbated difficulty in performing a working memory task with concurrent task demands suggests a specific limitation in executive control resources in PTSD. PMID:24165904

Working Memory and Mental Arithmetic: A Case for Dual Central Executive Resources

ERIC Educational Resources Information Center

Ketelsen, Kirk; Welsh, Marilyn

2010-01-01

The current study was designed to examine the possible existence of two limited-capacity pools of central executive resources: one each for verbal and visuospatial processing. Ninety-one college students (M age = 19.0, SD = 2.2) were administered a verbal working memory task that involved updating numbers in 2-, 3-, and 4-load conditions. The task…

The Interplay between Uncertainty Monitoring and Working Memory: Can Metacognition Become Automatic?

PubMed Central

Coutinho, Mariana V. C.; Redford, Joshua S.; Church, Barbara A.; Zakrzewski, Alexandria C.; Couchman, Justin J.; Smith, J. David

2016-01-01

The uncertainty response has grounded the study of metacognition in nonhuman animals. Recent research has explored the processes supporting uncertainty monitoring in monkeys. It revealed that uncertainty responding in contrast to perceptual responding depends on significant working memory resources. The aim of the present study was to expand this research by examining whether uncertainty monitoring is also working memory demanding in humans. To explore this issue, human participants were tested with or without a cognitive load on a psychophysical discrimination task including either an uncertainty response (allowing the decline of difficult trials) or a middle-perceptual response (labeling the same intermediate trial levels). The results demonstrated that cognitive load reduced uncertainty responding, but increased middle responding. However, this dissociation between uncertainty and middle responding was only observed when participants either lacked training or had very little training with the uncertainty response. If more training was provided, the effect of load was small. These results suggest that uncertainty responding is resource demanding, but with sufficient training, human participants can respond to uncertainty either by using minimal working memory resources or effectively sharing resources. These results are discussed in relation to the literature on animal and human metacognition. PMID:25971878

Role of Working Memory in Typically Developing Children's Complex Sentence Comprehension

ERIC Educational Resources Information Center

Montgomery, James W.; Magimairaj, Beula M.; O'Malley, Michelle H.

2008-01-01

The influence of three mechanisms of working memory (phonological short-term memory (PSTM capacity), attentional resource control/allocation, and processing speed) on children's complex (and simple) sentence comprehension was investigated. Fifty two children (6-12 years) completed a nonword repetition task (indexing PSTM), concurrent verbal…

Working Memory Tasks Differ in Factor Structure across Age Cohorts: Implications for Dedifferentiation

ERIC Educational Resources Information Center

Johnson, Wendy; Logie, Robert H.; Brockmole, James R.

2010-01-01

Researchers interested in working memory have debated whether it should be considered a single latent cognitive ability or a set of essentially independent latent abilities distinguished by domain-specific memory and/or processing resources. Simultaneously, researchers interested in cognitive aging have established that there are substantial…

Effects of load on the guidance of visual attention from working memory.

PubMed

Zhang, Bao; Zhang, John X; Huang, Sai; Kong, Lingyue; Wang, Suiping

2011-12-08

An active recent line of research on working memory and attention has shown that the visual attention can be top-down guided by working memory contents. The present study examined whether the guidance effect is modulated by memory load, i.e., the amount of information maintained in working memory. In a set of three experiments, participants were asked to perform a visual search task while maintaining several objects in working memory. The memory-driven attentional guidance effect was observed in all experiments when there were spare working memory resources. When memory load was increased from one item to two items, there was no sign that the guidance effect was attenuated. When load was further increased to four items, the guidance effect disappeared completely, indicating a clear impact of memory load on attentional guidance. Copyright © 2011 Elsevier Ltd. All rights reserved.

Unitary or Non-Unitary Nature of Working Memory? Evidence from Its Relation to General Fluid and Crystallized Intelligence

ERIC Educational Resources Information Center

Dang, Cai-Ping; Braeken, Johan; Ferrer, Emilio; Liu, Chang

2012-01-01

This study explored the controversy surrounding working memory: whether it is a unitary system providing general purpose resources or a more differentiated system with domain-specific sub-components. A total of 348 participants completed a set of 6 working memory tasks that systematically varied in storage target contents and type of information…

Interactive Effects of Working Memory Self-Regulatory Ability and Relevance Instructions on Text Processing

ERIC Educational Resources Information Center

Hamilton, Nancy Jo

2012-01-01

Reading is a process that requires the enactment of many cognitive processes. Each of these processes uses a certain amount of working memory resources, which are severely constrained by biology. More efficiency in the function of working memory may mediate the biological limits of same. Reading relevancy instructions may be one such method to…

Precision of working memory for visual motion sequences and transparent motion surfaces.

PubMed

Zokaei, Nahid; Gorgoraptis, Nikos; Bahrami, Bahador; Bays, Paul M; Husain, Masud

2011-12-01

Recent studies investigating working memory for location, color, and orientation support a dynamic resource model. We examined whether this might also apply to motion, using random dot kinematograms (RDKs) presented sequentially or simultaneously. Mean precision for motion direction declined as sequence length increased, with precision being lower for earlier RDKs. Two alternative models of working memory were compared specifically to distinguish between the contributions of different sources of error that corrupt memory (W. Zhang & S. J. Luck, 2008 vs. P. M. Bays, R. F. G. Catalao, & M. Husain, 2009). The latter provided a significantly better fit for the data, revealing that decrease in memory precision for earlier items is explained by an increase in interference from other items in a sequence rather than random guessing or a temporal decay of information. Misbinding feature attributes is an important source of error in working memory. Precision of memory for motion direction decreased when two RDKs were presented simultaneously as transparent surfaces, compared to sequential RDKs. However, precision was enhanced when one motion surface was prioritized, demonstrating that selective attention can improve recall precision. These results are consistent with a resource model that can be used as a general conceptual framework for understanding working memory across a range of visual features.

Hyperfocusing in Schizophrenia: Evidence from Interactions Between Working Memory and Eye Movements

PubMed Central

Luck, Steven J.; McClenon, Clara; Beck, Valerie M.; Hollingworth, Andrew; Leonard, Carly J.; Hahn, Britta; Robinson, Benjamin M.; Gold, James M.

2014-01-01

Recent research suggests that processing resources are focused more narrowly but more intensely in people with schizophrenia (PSZ) than in healthy control subjects (HCS), possibly reflecting local cortical circuit abnormalities. This hyperfocusing hypothesis leads to the counterintuitive prediction that, although PSZ cannot store as much information in working memory as HCS, the working memory representations that are present in PSZ may be more intense than those in HCS. To test this hypothesis, we used a task in which participants make a saccadic eye movement to a peripheral target and avoid a parafoveal nontarget while they are holding a color in working memory. Previous research with this task has shown that the parafoveal nontarget is more distracting when it matches the color being held in working memory. This effect should be enhanced in PSZ if their working memory representations are more intense. Consistent with this prediction, we found that the effect of a match between the distractor color and the memory color was larger in PSZ than in HCS. We also observed evidence that PSZ hyperfocused spatially on the region surrounding the fixation point. These results provide further evidence that some aspects of cognitive dysfunction in schizophrenia may be a result of a narrower and more intense focusing of processing resources. PMID:25089655

Hyperfocusing in schizophrenia: Evidence from interactions between working memory and eye movements.

PubMed

Luck, Steven J; McClenon, Clara; Beck, Valerie M; Hollingworth, Andrew; Leonard, Carly J; Hahn, Britta; Robinson, Benjamin M; Gold, James M

2014-11-01

Recent research suggests that processing resources are focused more narrowly but more intensely in people with schizophrenia (PSZ) than in healthy control subjects (HCS), possibly reflecting local cortical circuit abnormalities. This hyperfocusing hypothesis leads to the counterintuitive prediction that, although PSZ cannot store as much information in working memory as HCS, the working memory representations that are present in PSZ may be more intense than those in HCS. To test this hypothesis, we used a task in which participants make a saccadic eye movement to a peripheral target and avoid a parafoveal nontarget while they are holding a color in working memory. Previous research with this task has shown that the parafoveal nontarget is more distracting when it matches the color being held in working memory. This effect should be enhanced in PSZ if their working memory representations are more intense. Consistent with this prediction, we found that the effect of a match between the distractor color and the memory color was larger in PSZ than in HCS. We also observed evidence that PSZ hyperfocused spatially on the region surrounding the fixation point. These results provide further evidence that some aspects of cognitive dysfunction in schizophrenia may be a result of a narrower and more intense focusing of processing resources.

Do the Contents of Visual Working Memory Automatically Influence Attentional Selection During Visual Search?

PubMed Central

Woodman, Geoffrey F.; Luck, Steven J.

2007-01-01

In many theories of cognition, researchers propose that working memory and perception operate interactively. For example, in previous studies researchers have suggested that sensory inputs matching the contents of working memory will have an automatic advantage in the competition for processing resources. The authors tested this hypothesis by requiring observers to perform a visual search task while concurrently maintaining object representations in visual working memory. The hypothesis that working memory activation produces a simple but uncontrollable bias signal leads to the prediction that items matching the contents of working memory will automatically capture attention. However, no evidence for automatic attentional capture was obtained; instead, the participants avoided attending to these items. Thus, the contents of working memory can be used in a flexible manner for facilitation or inhibition of processing. PMID:17469973

Do the contents of visual working memory automatically influence attentional selection during visual search?

PubMed

Woodman, Geoffrey F; Luck, Steven J

2007-04-01

In many theories of cognition, researchers propose that working memory and perception operate interactively. For example, in previous studies researchers have suggested that sensory inputs matching the contents of working memory will have an automatic advantage in the competition for processing resources. The authors tested this hypothesis by requiring observers to perform a visual search task while concurrently maintaining object representations in visual working memory. The hypothesis that working memory activation produces a simple but uncontrollable bias signal leads to the prediction that items matching the contents of working memory will automatically capture attention. However, no evidence for automatic attentional capture was obtained; instead, the participants avoided attending to these items. Thus, the contents of working memory can be used in a flexible manner for facilitation or inhibition of processing.

Complex Sentence Comprehension and Working Memory in Children with Specific Language Impairment

ERIC Educational Resources Information Center

Montgomery, James W.; Evans, Julia L.

2009-01-01

Purpose: This study investigated the association of 2 mechanisms of working memory (phonological short-term memory [PSTM], attentional resource capacity/allocation) with the sentence comprehension of school-age children with specific language impairment (SLI) and 2 groups of control children. Method: Twenty-four children with SLI, 18 age-matched…

Time-Related Decay or Interference-Based Forgetting in Working Memory?

ERIC Educational Resources Information Center

Portrat, Sophie; Barrouillet, Pierre; Camos, Valerie

2008-01-01

The time-based resource-sharing model of working memory assumes that memory traces suffer from a time-related decay when attention is occupied by concurrent activities. Using complex continuous span tasks in which temporal parameters are carefully controlled, P. Barrouillet, S. Bernardin, S. Portrat, E. Vergauwe, & V. Camos (2007) recently…

Developmental Change in Working Memory Strategies: From Passive Maintenance to Active Refreshing

ERIC Educational Resources Information Center

Camos, Valerie; Barrouillet, Pierre

2011-01-01

Change in strategies is often mentioned as a source of memory development. However, though performance in working memory tasks steadily improves during childhood, theories differ in linking this development to strategy changes. Whereas some theories, such as the time-based resource-sharing model, invoke the age-related increase in use and…

Spatial sequences, but not verbal sequences, are vulnerable to general interference during retention in working memory.

PubMed

Morey, Candice C; Miron, Monica D

2016-12-01

Among models of working memory, there is not yet a consensus about how to describe functions specific to storing verbal or visual-spatial memories. We presented aural-verbal and visual-spatial lists simultaneously and sometimes cued one type of information after presentation, comparing accuracy in conditions with and without informative retro-cues. This design isolates interference due specifically to maintenance, which appears most clearly in the uncued trials, from interference due to encoding, which occurs in all dual-task trials. When recall accuracy was comparable between tasks, we found that spatial memory was worse in uncued than in retro-cued trials, whereas verbal memory was not. Our findings bolster proposals that maintenance of spatial serial order, like maintenance of visual materials more broadly, relies on general rather than specialized resources, while maintenance of verbal sequences may rely on domain-specific resources. We argue that this asymmetry should be explicitly incorporated into models of working memory. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

The development of strategy use in elementary school children: working memory and individual differences.

PubMed

Imbo, Ineke; Vandierendonck, André

2007-04-01

The current study tested the development of working memory involvement in children's arithmetic strategy selection and strategy efficiency. To this end, an experiment in which the dual-task method and the choice/no-choice method were combined was administered to 10- to 12-year-olds. Working memory was needed in retrieval, transformation, and counting strategies, but the ratio between available working memory resources and arithmetic task demands changed across development. More frequent retrieval use, more efficient memory retrieval, and more efficient counting processes reduced the working memory requirements. Strategy efficiency and strategy selection were also modified by individual differences such as processing speed, arithmetic skill, gender, and math anxiety. Short-term memory capacity, in contrast, was not related to children's strategy selection or strategy efficiency.

No Evidence for an Item Limit in Change Detection (Open Access)

DTIC Science & Technology

2013-02-28

memory : a reconsideration of mental storage capacity. Behav Brain Sci 24: 87–114. 17. Eng HY, Chen D, Jiang Y (2005) Visual working memory for simple...working memory can hold no more than a fixed number of items (‘‘item-limit models’’). Recent findings force us to consider the alternative view that working... memory is limited by the precision in stimulus encoding, with mean precision decreasing with increasing set size (‘‘continuous-resource models

The influence of time on task on mind wandering and visual working memory.

PubMed

Krimsky, Marissa; Forster, Daniel E; Llabre, Maria M; Jha, Amishi P

2017-12-01

Working memory relies on executive resources for successful task performance, with higher demands necessitating greater resource engagement. In addition to mnemonic demands, prior studies suggest that internal sources of distraction, such as mind wandering (i.e., having off-task thoughts) and greater time on task, may tax executive resources. Herein, the consequences of mnemonic demand, mind wandering, and time on task were investigated during a visual working memory task. Participants (N=143) completed a delayed-recognition visual working memory task, with mnemonic load for visual objects manipulated across trials (1 item=low load; 2 items=high load) and subjective mind wandering assessed intermittently throughout the experiment using a self-report Likert-type scale (1=on-task, 6=off-task). Task performance (correct/incorrect response) and self-reported mind wandering data were evaluated by hierarchical linear modeling to track trial-by-trial fluctuations. Performance declined with greater time on task, and the rate of decline was steeper for high vs low load trials. Self-reported mind wandering increased over time, and significantly varied asa function of both load and time on task. Participants reported greater mind wandering at the beginning of the experiment for low vs. high load trials; however, with greater time on task, more mind wandering was reported during high vs. low load trials. These results suggest that the availability of executive resources in support of working memory maintenance processes fluctuates in a demand-sensitive manner with time on task, and may be commandeered by mind wandering. Copyright © 2017 Elsevier B.V. All rights reserved.

Latent change models of adult cognition: are changes in processing speed and working memory associated with changes in episodic memory?

PubMed

Hertzog, Christopher; Dixon, Roger A; Hultsch, David F; MacDonald, Stuart W S

2003-12-01

The authors used 6-year longitudinal data from the Victoria Longitudinal Study (VLS) to investigate individual differences in amount of episodic memory change. Latent change models revealed reliable individual differences in cognitive change. Changes in episodic memory were significantly correlated with changes in other cognitive variables, including speed and working memory. A structural equation model for the latent change scores showed that changes in speed and working memory predicted changes in episodic memory, as expected by processing resource theory. However, these effects were best modeled as being mediated by changes in induction and fact retrieval. Dissociations were detected between cross-sectional ability correlations and longitudinal changes. Shuffling the tasks used to define the Working Memory latent variable altered patterns of change correlations.

Applying Neuroscience to Enhance Tactical Leader Cognitive Performance in Combat

DTIC Science & Technology

2011-12-16

to respond emotionally, (2) stress degrades the form of conscious attention know as “working memory ,” and (3) certain brain areas can be...Combat, Prefrontal Cortex, Tactical, Army, Working Memory 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a...sacrifices cognitive resources to respond emotionally, (2) stress degrades the form of conscious attention know as “working memory ,” and (3) certain

Working memory costs of task switching.

PubMed

Liefooghe, Baptist; Barrouillet, Pierre; Vandierendonck, André; Camos, Valérie

2008-05-01

Although many accounts of task switching emphasize the importance of working memory as a substantial source of the switch cost, there is a lack of evidence demonstrating that task switching actually places additional demands on working memory. The present study addressed this issue by implementing task switching in continuous complex span tasks with strictly controlled time parameters. A series of 4 experiments demonstrate that recall performance decreased as a function of the number of task switches and that the concurrent load of item maintenance had no influence on task switching. These results indicate that task switching induces a cost on working memory functioning. Implications for theories of task switching, working memory, and resource sharing are addressed.

Role of Working Memory in Children's Understanding Spoken Narrative: A Preliminary Investigation

ERIC Educational Resources Information Center

Montgomery, James W.; Polunenko, Anzhela; Marinellie, Sally A.

2009-01-01

The role of phonological short-term memory (PSTM), attentional resource capacity/allocation, and processing speed on children's spoken narrative comprehension was investigated. Sixty-seven children (6-11 years) completed a digit span task (PSTM), concurrent verbal processing and storage (CPS) task (resource capacity/allocation), auditory-visual…

The Effect of Noise on the Relationship Between Auditory Working Memory and Comprehension in School-Age Children.

PubMed

Sullivan, Jessica R; Osman, Homira; Schafer, Erin C

2015-06-01

The objectives of the current study were to examine the effect of noise (-5 dB SNR) on auditory comprehension and to examine its relationship with working memory. It was hypothesized that noise has a negative impact on information processing, auditory working memory, and comprehension. Children with normal hearing between the ages of 8 and 10 years were administered working memory and comprehension tasks in quiet and noise. The comprehension measure comprised 5 domains: main idea, details, reasoning, vocabulary, and understanding messages. Performance on auditory working memory and comprehension tasks were significantly poorer in noise than in quiet. The reasoning, details, understanding, and vocabulary subtests were particularly affected in noise (p < .05). The relationship between auditory working memory and comprehension was stronger in noise than in quiet, suggesting an increased contribution of working memory. These data suggest that school-age children's auditory working memory and comprehension are negatively affected by noise. Performance on comprehension tasks in noise is strongly related to demands placed on working memory, supporting the theory that degrading listening conditions draws resources away from the primary task.

Effects of motor congruence on visual working memory.

PubMed

Quak, Michel; Pecher, Diane; Zeelenberg, Rene

2014-10-01

Grounded-cognition theories suggest that memory shares processing resources with perception and action. The motor system could be used to help memorize visual objects. In two experiments, we tested the hypothesis that people use motor affordances to maintain object representations in working memory. Participants performed a working memory task on photographs of manipulable and nonmanipulable objects. The manipulable objects were objects that required either a precision grip (i.e., small items) or a power grip (i.e., large items) to use. A concurrent motor task that could be congruent or incongruent with the manipulable objects caused no difference in working memory performance relative to nonmanipulable objects. Moreover, the precision- or power-grip motor task did not affect memory performance on small and large items differently. These findings suggest that the motor system plays no part in visual working memory.

Working Memory Impairments in Chromosome 22q11.2 Deletion Syndrome: The Roles of Anxiety and Stress Physiology.

PubMed

Sanders, Ashley F P; Hobbs, Diana A; Stephenson, David D; Laird, Robert D; Beaton, Elliott A

2017-04-01

Stress and anxiety have a negative impact on working memory systems by competing for executive resources and attention. Broad memory deficits, anxiety, and elevated stress have been reported in individuals with chromosome 22q11.2 deletion syndrome (22q11.2DS). We investigated anxiety and physiological stress reactivity in relation to visuospatial working memory impairments in 20 children with 22q11.2DS and 32 typically developing (TD) children ages 7 to 16. Children with 22q11.2DS demonstrated poorer working memory, reduced post-stress respiratory sinus arrhythmia recovery, and overall increased levels of cortisol in comparison to TD children. Anxiety, but not physiological stress responsivity, mediated the relationship between 22q11.2DS diagnosis and visuospatial working memory impairment. Findings indicate that anxiety exacerbates impaired working memory in children with 22q11.2DS.

Dissociation of performance and subjective measures of workload

NASA Technical Reports Server (NTRS)

Yeh, Yei-Yu; Wickens, Christopher D.

1988-01-01

A theory is presented to identify sources that produce dissociations between performance and subjective measures of workload. The theory states that performance is determined by (1) amount of resources invested, (2) resource efficiency, and (3) degree of competition for common resources in a multidimensional space described in the multiple-resources model. Subjective perception of workload, multidimensional in nature, increases with greater amounts of resource investment and with greater demands on working memory. Performance and subjective workload measures dissociate when greater resources are invested to improve performance of a resource-limited task; when demands on working memory are increased by time-sharing between concurrent tasks or between display elements; and when performance is sensitive to resource competition and subjective measures are more sensitive to total investment. These dissociation findings and their implications are discussed and directions for future research are suggested.

A Resource Guide to Assistive Technology for Memory and Organization. Second Edition.

ERIC Educational Resources Information Center

McHale, Kathy; McHale, Sara, Ed.

The second edition of this guide to assistive technology for memory and organization is intended for professionals working with people who have learning disabilities, attention deficit disorders, neurological conditions, and psychological problems. It contains expanded and new appendices as well as new information about free Internet resources,…

Working memory dependence of spatial contextual cueing for visual search.

PubMed

Pollmann, Stefan

2018-05-10

When spatial stimulus configurations repeat in visual search, a search facilitation, resulting in shorter search times, can be observed that is due to incidental learning. This contextual cueing effect appears to be rather implicit, uncorrelated with observers' explicit memory of display configurations. Nevertheless, as I review here, this search facilitation due to contextual cueing depends on visuospatial working memory resources, and it disappears when visuospatial working memory is loaded by a concurrent delayed match to sample task. However, the search facilitation immediately recovers for displays learnt under visuospatial working memory load when this load is removed in a subsequent test phase. Thus, latent learning of visuospatial configurations does not depend on visuospatial working memory, but the expression of learning, as memory-guided search in repeated displays, does. This working memory dependence has also consequences for visual search with foveal vision loss, where top-down controlled visual exploration strategies pose high demands on visuospatial working memory, in this way interfering with memory-guided search in repeated displays. Converging evidence for the contribution of working memory to contextual cueing comes from neuroimaging data demonstrating that distinct cortical areas along the intraparietal sulcus as well as more ventral parieto-occipital cortex are jointly activated by visual working memory and contextual cueing. © 2018 The British Psychological Society.

Accounting for stimulus-specific variation in precision reveals a discrete capacity limit in visual working memory

PubMed Central

Pratte, Michael S.; Park, Young Eun; Rademaker, Rosanne L.; Tong, Frank

2016-01-01

If we view a visual scene that contains many objects, then momentarily close our eyes, some details persist while others seem to fade. Discrete models of visual working memory (VWM) assume that only a few items can be actively maintained in memory, beyond which pure guessing will emerge. Alternatively, continuous resource models assume that all items in a visual scene can be stored with some precision. Distinguishing between these competing models is challenging, however, as resource models that allow for stochastically variable precision (across items and trials) can produce error distributions that resemble random guessing behavior. Here, we evaluated the hypothesis that a major source of variability in VWM performance arises from systematic variation in precision across the stimuli themselves; such stimulus-specific variability can be incorporated into both discrete-capacity and variable-precision resource models. Participants viewed multiple oriented gratings, and then reported the orientation of a cued grating from memory. When modeling the overall distribution of VWM errors, we found that the variable-precision resource model outperformed the discrete model. However, VWM errors revealed a pronounced “oblique effect”, with larger errors for oblique than cardinal orientations. After this source of variability was incorporated into both models, we found that the discrete model provided a better account of VWM errors. Our results demonstrate that variable precision across the stimulus space can lead to an unwarranted advantage for resource models that assume stochastically variable precision. When these deterministic sources are adequately modeled, human working memory performance reveals evidence of a discrete capacity limit. PMID:28004957

Accounting for stimulus-specific variation in precision reveals a discrete capacity limit in visual working memory.

PubMed

Pratte, Michael S; Park, Young Eun; Rademaker, Rosanne L; Tong, Frank

2017-01-01

If we view a visual scene that contains many objects, then momentarily close our eyes, some details persist while others seem to fade. Discrete models of visual working memory (VWM) assume that only a few items can be actively maintained in memory, beyond which pure guessing will emerge. Alternatively, continuous resource models assume that all items in a visual scene can be stored with some precision. Distinguishing between these competing models is challenging, however, as resource models that allow for stochastically variable precision (across items and trials) can produce error distributions that resemble random guessing behavior. Here, we evaluated the hypothesis that a major source of variability in VWM performance arises from systematic variation in precision across the stimuli themselves; such stimulus-specific variability can be incorporated into both discrete-capacity and variable-precision resource models. Participants viewed multiple oriented gratings, and then reported the orientation of a cued grating from memory. When modeling the overall distribution of VWM errors, we found that the variable-precision resource model outperformed the discrete model. However, VWM errors revealed a pronounced "oblique effect," with larger errors for oblique than cardinal orientations. After this source of variability was incorporated into both models, we found that the discrete model provided a better account of VWM errors. Our results demonstrate that variable precision across the stimulus space can lead to an unwarranted advantage for resource models that assume stochastically variable precision. When these deterministic sources are adequately modeled, human working memory performance reveals evidence of a discrete capacity limit. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Visual-spatial processing and working-memory load as a function of negative and positive psychotic-like experiences.

PubMed

Abu-Akel, A; Reniers, R L E P; Wood, S J

2016-09-01

Patients with schizophrenia show impairments in working-memory and visual-spatial processing, but little is known about the dynamic interplay between the two. To provide insight into this important question, we examined the effect of positive and negative symptom expressions in healthy adults on perceptual processing while concurrently performing a working-memory task that requires the allocations of various degrees of cognitive resources. The effect of positive and negative symptom expressions in healthy adults (N = 91) on perceptual processing was examined in a dual-task paradigm of visual-spatial working memory (VSWM) under three conditions of cognitive load: a baseline condition (with no concurrent working-memory demand), a low VSWM load condition, and a high VSWM load condition. Participants overall performed more efficiently (i.e., faster) with increasing cognitive load. This facilitation in performance was unrelated to symptom expressions. However, participants with high-negative, low-positive symptom expressions were less accurate in the low VSWM condition compared to the baseline and the high VSWM load conditions. Attenuated, subclinical expressions of psychosis affect cognitive performance that is impaired in schizophrenia. The "resource limitations hypothesis" may explain the performance of the participants with high-negative symptom expressions. The dual-task of visual-spatial processing and working memory may be beneficial to assessing the cognitive phenotype of individuals with high risk for schizophrenia spectrum disorders.

Working Memory Systems in the Rat.

PubMed

Bratch, Alexander; Kann, Spencer; Cain, Joshua A; Wu, Jie-En; Rivera-Reyes, Nilda; Dalecki, Stefan; Arman, Diana; Dunn, Austin; Cooper, Shiloh; Corbin, Hannah E; Doyle, Amanda R; Pizzo, Matthew J; Smith, Alexandra E; Crystal, Jonathon D

2016-02-08

A fundamental feature of memory in humans is the ability to simultaneously work with multiple types of information using independent memory systems. Working memory is conceptualized as two independent memory systems under executive control [1, 2]. Although there is a long history of using the term "working memory" to describe short-term memory in animals, it is not known whether multiple, independent memory systems exist in nonhumans. Here, we used two established short-term memory approaches to test the hypothesis that spatial and olfactory memory operate as independent working memory resources in the rat. In the olfactory memory task, rats chose a novel odor from a gradually incrementing set of old odors [3]. In the spatial memory task, rats searched for a depleting food source at multiple locations [4]. We presented rats with information to hold in memory in one domain (e.g., olfactory) while adding a memory load in the other domain (e.g., spatial). Control conditions equated the retention interval delay without adding a second memory load. In a further experiment, we used proactive interference [5-7] in the spatial domain to compromise spatial memory and evaluated the impact of adding an olfactory memory load. Olfactory and spatial memory are resistant to interference from the addition of a memory load in the other domain. Our data suggest that olfactory and spatial memory draw on independent working memory systems in the rat. Copyright © 2016 Elsevier Ltd. All rights reserved.

Working Memory Impairments in Chromosome 22q11.2 Deletion Syndrome: The Roles of Anxiety and Stress Physiology

ERIC Educational Resources Information Center

Sanders, Ashley F.; Hobbs, Diana A.; Stephenson, David D.; Laird, Robert D.; Beaton, Elliott A.

2017-01-01

Stress and anxiety have a negative impact on working memory systems by competing for executive resources and attention. Broad memory deficits, anxiety, and elevated stress have been reported in individuals with chromosome 22q11.2 deletion syndrome (22q11.2DS). We investigated anxiety and physiological stress reactivity in relation to visuospatial…

Domain-general involvement of the posterior frontolateral cortex in time-based resource-sharing in working memory: An fMRI study.

PubMed

Vergauwe, Evie; Hartstra, Egbert; Barrouillet, Pierre; Brass, Marcel

2015-07-15

Working memory is often defined in cognitive psychology as a system devoted to the simultaneous processing and maintenance of information. In line with the time-based resource-sharing model of working memory (TBRS; Barrouillet and Camos, 2015; Barrouillet et al., 2004), there is accumulating evidence that, when memory items have to be maintained while performing a concurrent activity, memory performance depends on the cognitive load of this activity, independently of the domain involved. The present study used fMRI to identify regions in the brain that are sensitive to variations in cognitive load in a domain-general way. More precisely, we aimed at identifying brain areas that activate during maintenance of memory items as a direct function of the cognitive load induced by both verbal and spatial concurrent tasks. Results show that the right IFJ and bilateral SPL/IPS are the only areas showing an increased involvement as cognitive load increases and do so in a domain general manner. When correlating the fMRI signal with the approximated cognitive load as defined by the TBRS model, it was shown that the main focus of the cognitive load-related activation is located in the right IFJ. The present findings indicate that the IFJ makes domain-general contributions to time-based resource-sharing in working memory and allowed us to generate the novel hypothesis by which the IFJ might be the neural basis for the process of rapid switching. We argue that the IFJ might be a crucial part of a central attentional bottleneck in the brain because of its inability to upload more than one task rule at once. Copyright © 2015 Elsevier Inc. All rights reserved.

Visuo-spatialWorking Memory as a Limited Resource of Cognitive Processing

NASA Astrophysics Data System (ADS)

Zimmer, Hubert D.; Münzer, Stefan; Umla-Runge, Katja

Working memory is considered a cognitive component that mainly serves two functions. It temporarily maintains information that was either perceived but is no longer present in the environment, or that was internally generated, and it supplies a work space for transforming and manipulating elements of perception and thinking. Both functions are relevant for a successful interaction with the environment and it is therefore not surprising that WM is a central topic of research in the field of general psychology. This interest is further increased by the fact that WM is seen as a limited resource that constrains cognitive performances.

Negative affect improves the quality of memories: trading capacity for precision in sensory and working memory.

PubMed

Spachtholz, Philipp; Kuhbandner, Christof; Pekrun, Reinhard

2014-08-01

Research has shown that negative affect reduces working memory capacity. Commonly, this effect has been attributed to an allocation of resources to task-irrelevant thoughts, suggesting that negative affect has detrimental consequences for working memory performance. However, rather than simply being a detrimental effect, the affect-induced capacity reduction may reflect a trading of capacity for precision of stored representations. To test this hypothesis, we induced neutral or negative affect and concurrently measured the number and precision of representations stored in sensory and working memory. Compared with neutral affect, negative affect reduced the capacity of both sensory and working memory. However, in both memory systems, this decrease in capacity was accompanied by an increase in precision. These findings demonstrate that observers unintentionally trade capacity for precision as a function of affective state and indicate that negative affect can be beneficial for the quality of memories. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Two Maintenance Mechanisms of Verbal Information in Working Memory

ERIC Educational Resources Information Center

Camos, V.; Lagner, P.; Barrouillet, P.

2009-01-01

The present study evaluated the interplay between two mechanisms of maintenance of verbal information in working memory, namely articulatory rehearsal as described in Baddeley's model, and attentional refreshing as postulated in Barrouillet and Camos's Time-Based Resource-Sharing (TBRS) model. In four experiments using complex span paradigm, we…

The Role of Attention in Item-Item Binding in Visual Working Memory

ERIC Educational Resources Information Center

Peterson, Dwight J.; Naveh-Benjamin, Moshe

2017-01-01

An important yet unresolved question regarding visual working memory (VWM) relates to whether or not binding processes within VWM require additional attentional resources compared with processing solely the individual components comprising these bindings. Previous findings indicate that binding of surface features (e.g., colored shapes) within VWM…

The Episodic Buffer in Children with Intellectual Disabilities: An Exploratory Study

ERIC Educational Resources Information Center

Henry, Lucy A.

2010-01-01

Performance on three verbal measures (story recall, paired associated learning, category fluency) designed to assess the integration of long-term semantic and linguistic knowledge, phonological working memory and executive resources within the proposed "episodic buffer" of working memory (Baddeley, 2007) was assessed in children with intellectual…

Dorsal and ventral working memory-related brain areas support distinct processes in contextual cueing.

PubMed

Manginelli, Angela A; Baumgartner, Florian; Pollmann, Stefan

2013-02-15

Behavioral evidence suggests that the use of implicitly learned spatial contexts for improved visual search may depend on visual working memory resources. Working memory may be involved in contextual cueing in different ways: (1) for keeping implicitly learned working memory contents available during search or (2) for the capture of attention by contexts retrieved from memory. We mapped brain areas that were modulated by working memory capacity. Within these areas, activation was modulated by contextual cueing along the descending segment of the intraparietal sulcus, an area that has previously been related to maintenance of explicit memories. Increased activation for learned displays, but not modulated by the size of contextual cueing, was observed in the temporo-parietal junction area, previously associated with the capture of attention by explicitly retrieved memory items, and in the ventral visual cortex. This pattern of activation extends previous research on dorsal versus ventral stream functions in memory guidance of attention to the realm of attentional guidance by implicit memory. Copyright © 2012 Elsevier Inc. All rights reserved.

Object selection costs in visual working memory: A diffusion model analysis of the focus of attention.

PubMed

Sewell, David K; Lilburn, Simon D; Smith, Philip L

2016-11-01

A central question in working memory research concerns the degree to which information in working memory is accessible to other cognitive processes (e.g., decision-making). Theories assuming that the focus of attention can only store a single object at a time require the focus to orient to a target representation before further processing can occur. The need to orient the focus of attention implies that single-object accounts typically predict response time costs associated with object selection even when working memory is not full (i.e., memory load is less than 4 items). For other theories that assume storage of multiple items in the focus of attention, predictions depend on specific assumptions about the way resources are allocated among items held in the focus, and how this affects the time course of retrieval of items from the focus. These broad theoretical accounts have been difficult to distinguish because conventional analyses fail to separate components of empirical response times related to decision-making from components related to selection and retrieval processes associated with accessing information in working memory. To better distinguish these response time components from one another, we analyze data from a probed visual working memory task using extensions of the diffusion decision model. Analysis of model parameters revealed that increases in memory load resulted in (a) reductions in the quality of the underlying stimulus representations in a manner consistent with a sample size model of visual working memory capacity and (b) systematic increases in the time needed to selectively access a probed representation in memory. The results are consistent with single-object theories of the focus of attention. The results are also consistent with a subset of theories that assume a multiobject focus of attention in which resource allocation diminishes both the quality and accessibility of the underlying representations. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

The attentional blink reveals serial working memory encoding: evidence from virtual and human event-related potentials.

PubMed

Craston, Patrick; Wyble, Brad; Chennu, Srivas; Bowman, Howard

2009-03-01

Observers often miss a second target (T2) if it follows an identified first target item (T1) within half a second in rapid serial visual presentation (RSVP), a finding termed the attentional blink. If two targets are presented in immediate succession, however, accuracy is excellent (Lag 1 sparing). The resource sharing hypothesis proposes a dynamic distribution of resources over a time span of up to 600 msec during the attentional blink. In contrast, the ST(2) model argues that working memory encoding is serial during the attentional blink and that, due to joint consolidation, Lag 1 is the only case where resources are shared. Experiment 1 investigates the P3 ERP component evoked by targets in RSVP. The results suggest that, in this context, P3 amplitude is an indication of bottom-up strength rather than a measure of cognitive resource allocation. Experiment 2, employing a two-target paradigm, suggests that T1 consolidation is not affected by the presentation of T2 during the attentional blink. However, if targets are presented in immediate succession (Lag 1 sparing), they are jointly encoded into working memory. We use the ST(2) model's neural network implementation, which replicates a range of behavioral results related to the attentional blink, to generate "virtual ERPs" by summing across activation traces. We compare virtual to human ERPs and show how the results suggest a serial nature of working memory encoding as implied by the ST(2) model.

Ensemble coding remains accurate under object and spatial visual working memory load.

PubMed

Epstein, Michael L; Emmanouil, Tatiana A

2017-10-01

A number of studies have provided evidence that the visual system statistically summarizes large amounts of information that would exceed the limitations of attention and working memory (ensemble coding). However the necessity of working memory resources for ensemble coding has not yet been tested directly. In the current study, we used a dual task design to test the effect of object and spatial visual working memory load on size averaging accuracy. In Experiment 1, we tested participants' accuracy in comparing the mean size of two sets under various levels of object visual working memory load. Although the accuracy of average size judgments depended on the difference in mean size between the two sets, we found no effect of working memory load. In Experiment 2, we tested the same average size judgment while participants were under spatial visual working memory load, again finding no effect of load on averaging accuracy. Overall our results reveal that ensemble coding can proceed unimpeded and highly accurately under both object and spatial visual working memory load, providing further evidence that ensemble coding reflects a basic perceptual process distinct from that of individual object processing.

Dopamine D1 signaling organizes network dynamics underlying working memory.

PubMed

Roffman, Joshua L; Tanner, Alexandra S; Eryilmaz, Hamdi; Rodriguez-Thompson, Anais; Silverstein, Noah J; Ho, New Fei; Nitenson, Adam Z; Chonde, Daniel B; Greve, Douglas N; Abi-Dargham, Anissa; Buckner, Randy L; Manoach, Dara S; Rosen, Bruce R; Hooker, Jacob M; Catana, Ciprian

2016-06-01

Local prefrontal dopamine signaling supports working memory by tuning pyramidal neurons to task-relevant stimuli. Enabled by simultaneous positron emission tomography-magnetic resonance imaging (PET-MRI), we determined whether neuromodulatory effects of dopamine scale to the level of cortical networks and coordinate their interplay during working memory. Among network territories, mean cortical D1 receptor densities differed substantially but were strongly interrelated, suggesting cross-network regulation. Indeed, mean cortical D1 density predicted working memory-emergent decoupling of the frontoparietal and default networks, which respectively manage task-related and internal stimuli. In contrast, striatal D1 predicted opposing effects within these two networks but no between-network effects. These findings specifically link cortical dopamine signaling to network crosstalk that redirects cognitive resources to working memory, echoing neuromodulatory effects of D1 signaling on the level of cortical microcircuits.

Working Memory in Children: A Time-Constrained Functioning Similar to Adults

ERIC Educational Resources Information Center

Portrat, Sophie; Camos, Valerie; Barrouillet, Pierre

2009-01-01

Within the time-based resource-sharing (TBRS) model, we tested a new conception of the relationships between processing and storage in which the core mechanisms of working memory (WM) are time constrained. However, our previous studies were restricted to adults. The current study aimed at demonstrating that these mechanisms are present and…

Cognitive Load Theory: An Empirical Study of Anxiety and Task Performance in Language Learning

ERIC Educational Resources Information Center

Chen, I-Jung; Chang, Chi-Cheng

2009-01-01

Introduction: This study explores the relationship among three variables--cognitive load, foreign language anxiety, and task performance. Cognitive load refers to the load imposed on working memory while performing a particular task. The authors hypothesized that anxiety consumes the resources of working memory, leaving less capacity for cognitive…

Selective Interference on the Holistic Processing of Faces in Working Memory

ERIC Educational Resources Information Center

Cheung, Olivia S.; Gauthier, Isabel

2010-01-01

Faces and objects of expertise compete for early perceptual processes and holistic processing resources (Gauthier, Curran, Curby, & Collins, 2003). Here, we examined the nature of interference on holistic face processing in working memory by comparing how various types of loads affect selective attention to parts of face composites. In dual…

Working Memory, Motivation, and Teacher-Initiated Learning

NASA Astrophysics Data System (ADS)

Brooks, David W.; Shell, Duane F.

2006-03-01

Working memory is where we "think" as we learn. A notion that emerges as a synthesis from several threads in the research literatures of cognition, motivation, and connectionism is that motivation in learning is the process whereby working memory resource allocation is instigated and sustained. This paper reviews much literature on motivation and working memory, and concludes that the apparent novelty of the proposal offered to describe motivation in terms of working memory results from the apparent lack of cross-channel exchange among these research traditions. The relation between working memory and motivation is explored in the context of the interactive compensatory model of learning (ICML) in which learning is considered to result from the interaction of ability, motivation, and prior learning. The ICML is recast in light of the revised definition of motivation offered here. This paper goes on to suggest ways in which a range of teaching and learning issues and activities may be reconceptualized in the context of a model emphasizing a learner's working memory that makes use of chunks of previously acquired knowledge.

Discrete-Slots Models of Visual Working-Memory Response Times

PubMed Central

Donkin, Christopher; Nosofsky, Robert M.; Gold, Jason M.; Shiffrin, Richard M.

2014-01-01

Much recent research has aimed to establish whether visual working memory (WM) is better characterized by a limited number of discrete all-or-none slots or by a continuous sharing of memory resources. To date, however, researchers have not considered the response-time (RT) predictions of discrete-slots versus shared-resources models. To complement the past research in this field, we formalize a family of mixed-state, discrete-slots models for explaining choice and RTs in tasks of visual WM change detection. In the tasks under investigation, a small set of visual items is presented, followed by a test item in 1 of the studied positions for which a change judgment must be made. According to the models, if the studied item in that position is retained in 1 of the discrete slots, then a memory-based evidence-accumulation process determines the choice and the RT; if the studied item in that position is missing, then a guessing-based accumulation process operates. Observed RT distributions are therefore theorized to arise as probabilistic mixtures of the memory-based and guessing distributions. We formalize an analogous set of continuous shared-resources models. The model classes are tested on individual subjects with both qualitative contrasts and quantitative fits to RT-distribution data. The discrete-slots models provide much better qualitative and quantitative accounts of the RT and choice data than do the shared-resources models, although there is some evidence for “slots plus resources” when memory set size is very small. PMID:24015956

Remembering faces and scenes: The mixed-category advantage in visual working memory.

PubMed

Jiang, Yuhong V; Remington, Roger W; Asaad, Anthony; Lee, Hyejin J; Mikkalson, Taylor C

2016-09-01

We examined the mixed-category memory advantage for faces and scenes to determine how domain-specific cortical resources constrain visual working memory. Consistent with previous findings, visual working memory for a display of 2 faces and 2 scenes was better than that for a display of 4 faces or 4 scenes. This pattern was unaffected by manipulations of encoding duration. However, the mixed-category advantage was carried solely by faces: Memory for scenes was not better when scenes were encoded with faces rather than with other scenes. The asymmetry between faces and scenes was found when items were presented simultaneously or sequentially, centrally, or peripherally, and when scenes were drawn from a narrow category. A further experiment showed a mixed-category advantage in memory for faces and bodies, but not in memory for scenes and objects. The results suggest that unique category-specific interactions contribute significantly to the mixed-category advantage in visual working memory. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Community-based memorials to September 11, 2001: environmental stewardship as memory work

Treesearch

Erika S. Svendsen; Lindsay K. Campbell

2014-01-01

This chapter investigates how people use trees, parks, gardens, and other natural resources as raw materials in and settings for memorials to September 11, 2001. In particular, we focus on 'found space living memorials', which we define as sites that are community-managed, re-appropriated from their prior use, often carved out of the public right-of-way, and...

Working memory as separable subsystems: a study with Portuguese primary school children.

PubMed

Campos, Isabel S; Almeida, Leandro S; Ferreira, Aristides I; Martinez, Luis F

2013-01-01

Although much research has been done to study the working memory structure in children in their first school years, the relation of cognitive constructs involved in this process remains uncertain. In particular, it is unclear whether working memory is a domain general construct that coordinates separate codes of verbal and visuospatial storage or whether it is a domain-specific construct with distinct resources of verbal and visuospatial information. This paper investigates the structure of working memory, by using the Working Memory Test Battery for Children (WMTB-C) and by doing confirmatory factor analyses (CFAs) on a sample of Portuguese children (n = 103) between 8 and 9 years of age. The results of the confirmatory factor analyses that provide the best fit of the data correspond to the model that includes Central Executive and Visuospatial Sketchpad in the same factor, co-varying with a Phonological Loop factor. Moreover, the traditional working memory tripartite structure--based on the Baddeley and Hitch Model--revealed good fit to the data.

Music training and working memory: an ERP study.

PubMed

George, Elyse M; Coch, Donna

2011-04-01

While previous research has suggested that music training is associated with improvements in various cognitive and linguistic skills, the mechanisms mediating or underlying these associations are mostly unknown. Here, we addressed the hypothesis that previous music training is related to improved working memory. Using event-related potentials (ERPs) and a standardized test of working memory, we investigated both neural and behavioral aspects of working memory in college-aged, non-professional musicians and non-musicians. Behaviorally, musicians outperformed non-musicians on standardized subtests of visual, phonological, and executive memory. ERPs were recorded in standard auditory and visual oddball paradigms (participants responded to infrequent deviant stimuli embedded in lists of standard stimuli). Electrophysiologically, musicians demonstrated faster updating of working memory (shorter latency P300s) in both the auditory and visual domains and musicians allocated more neural resources to auditory stimuli (larger amplitude P300), showing increased sensitivity to the auditory standard/deviant difference and less effortful updating of auditory working memory. These findings demonstrate that long-term music training is related to improvements in working memory, in both the auditory and visual domains and in terms of both behavioral and ERP measures. Copyright © 2011 Elsevier Ltd. All rights reserved.

High working memory load impairs the effect of cognitive reappraisal on emotional response: Evidence from an event-related potential study.

PubMed

Gan, Shuzhen; Yang, Jianfeng; Chen, Xuhai; Zhang, Xiuping; Yang, Yufang

2017-02-03

This study investigates how the working memory (WM) load influenced the efficacy of cognitive reappraisal, a frequently used strategy for emotion regulation. In a dual-task paradigm, the participants were required to perform a high-load or a low-load memory task and simultaneously reappraise aversive pictures with a negative or a neutral meaning. In the low-load condition, we found that the amplitude of emotion-enhanced late positive potential (LPP) was significantly decreased by neutral reappraisal compared to negative reappraisal. In the high-load condition, this regulatory effect of reappraisal disappeared. These results suggest that successful reappraisal relies on cognitive resources and WM processes. If the necessary resources involved in reappraisal are over-depleted by a concurrent memory task, the reappraisal effect will be impaired. Moreover, we found that emotion-enhanced LPP was significant in both of the high-load and low-load tasks, which suggests that emotional electrocortical response may not be susceptible to the available resources. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

The role of sleep in cognitive processing: focusing on memory consolidation.

PubMed

Chambers, Alexis M

2017-05-01

Research indicates that sleep promotes various cognitive functions, such as decision-making, language, categorization, and memory. Of these, most work has focused on the influence of sleep on memory, with ample work showing that sleep enhances memory consolidation, a process that stores new memories in the brain over time. Recent psychological and neurophysiological research has vastly increased understanding of this process. Such work not only suggests that consolidation relies on plasticity-related mechanisms that reactivate and stabilize memory representations, but also that this process may be experimentally manipulated by methods that target which memory traces are reactivated during sleep. Furthermore, aside from memory storage capabilities, memory consolidation also appears to reorganize and integrate memories with preexisting knowledge, which may facilitate the discovery of underlying rules and associations that benefit other cognitive functioning, including problem solving and creativity. WIREs Cogn Sci 2017, 8:e1433. doi: 10.1002/wcs.1433 For further resources related to this article, please visit the WIREs website. © 2017 Wiley Periodicals, Inc.

When study abroad experience fails to deliver: The internal resources threshold effect

PubMed Central

Sunderman, Gretchen; Kroll, Judith F.

2009-01-01

Some second language (L2) learners return from study abroad experiences with seemingly no change in their L2 ability. In this study we investigate whether a certain level of internal cognitive resources is necessary in order for individuals to take full advantage of the study abroad experience. Specifically, we examined the role of working memory resources in lexical comprehension and production for learners who had or had not studied abroad. Participants included native English learners of Spanish. Participants completed a translation recognition task and a picture-naming task. The results suggest that individuals who lack a certain threshold of working memory resources are unable to benefit from the study abroad context in terms of being able to produce accurately in the L2. PMID:19714256

The Impact of Storage on Processing: How Is Information Maintained in Working Memory?

ERIC Educational Resources Information Center

Vergauwe, Evie; Camos, Valérie; Barrouillet, Pierre

2014-01-01

Working memory is typically defined as a system devoted to the simultaneous maintenance and processing of information. However, the interplay between these 2 functions is still a matter of debate in the literature, with views ranging from complete independence to complete dependence. The time-based resource-sharing model assumes that a central…

The Role of Anxiety and Working Memory in Gender Differences in Mathematics

ERIC Educational Resources Information Center

Ganley, Colleen M.; Vasilyeva, Marina

2014-01-01

This research examined a potential mechanism underlying gender differences in math performance by testing a mediation model in which women's higher anxiety taxes their working memory resources, leading to underperformance on a mathematics test. Participants for the 2 studies were college students (N = 87, N = 118) who completed an anxiety measure,…

The Effect of Non-Visual Working Memory Load on Top-Down Modulation of Visual Processing

ERIC Educational Resources Information Center

Rissman, Jesse; Gazzaley, Adam; D'Esposito, Mark

2009-01-01

While a core function of the working memory (WM) system is the active maintenance of behaviorally relevant sensory representations, it is also critical that distracting stimuli are appropriately ignored. We used functional magnetic resonance imaging to examine the role of domain-general WM resources in the top-down attentional modulation of…

More than a filter: Feature-based attention regulates the distribution of visual working memory resources.

PubMed

Dube, Blaire; Emrich, Stephen M; Al-Aidroos, Naseem

2017-10-01

Across 2 experiments we revisited the filter account of how feature-based attention regulates visual working memory (VWM). Originally drawing from discrete-capacity ("slot") models, the filter account proposes that attention operates like the "bouncer in the brain," preventing distracting information from being encoded so that VWM resources are reserved for relevant information. Given recent challenges to the assumptions of discrete-capacity models, we investigated whether feature-based attention plays a broader role in regulating memory. Both experiments used partial report tasks in which participants memorized the colors of circle and square stimuli, and we provided a feature-based goal by manipulating the likelihood that 1 shape would be probed over the other across a range of probabilities. By decomposing participants' responses using mixture and variable-precision models, we estimated the contributions of guesses, nontarget responses, and imprecise memory representations to their errors. Consistent with the filter account, participants were less likely to guess when the probed memory item matched the feature-based goal. Interestingly, this effect varied with goal strength, even across high probabilities where goal-matching information should always be prioritized, demonstrating strategic control over filter strength. Beyond this effect of attention on which stimuli were encoded, we also observed effects on how they were encoded: Estimates of both memory precision and nontarget errors varied continuously with feature-based attention. The results offer support for an extension to the filter account, where feature-based attention dynamically regulates the distribution of resources within working memory so that the most relevant items are encoded with the greatest precision. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Executive and Perceptual Distraction in Visual Working Memory

PubMed Central

2017-01-01

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. PMID:28414499

Attentional priority determines working memory precision.

PubMed

Klyszejko, Zuzanna; Rahmati, Masih; Curtis, Clayton E

2014-12-01

Visual working memory is a system used to hold information actively in mind for a limited time. The number of items and the precision with which we can store information has limits that define its capacity. How much control do we have over the precision with which we store information when faced with these severe capacity limitations? Here, we tested the hypothesis that rank-ordered attentional priority determines the precision of multiple working memory representations. We conducted two psychophysical experiments that manipulated the priority of multiple items in a two-alternative forced choice task (2AFC) with distance discrimination. In Experiment 1, we varied the probabilities with which memorized items were likely to be tested. To generalize the effects of priority beyond simple cueing, in Experiment 2, we manipulated priority by varying monetary incentives contingent upon successful memory for items tested. Moreover, we illustrate our hypothesis using a simple model that distributed attentional resources across items with rank-ordered priorities. Indeed, we found evidence in both experiments that priority affects the precision of working memory in a monotonic fashion. Our results demonstrate that representations of priority may provide a mechanism by which resources can be allocated to increase the precision with which we encode and briefly store information. Copyright © 2014 Elsevier Ltd. All rights reserved.

Different developmental trajectories across feature types support a dynamic field model of visual working memory development.

PubMed

Simmering, Vanessa R; Miller, Hilary E; Bohache, Kevin

2015-05-01

Research on visual working memory has focused on characterizing the nature of capacity limits as "slots" or "resources" based almost exclusively on adults' performance with little consideration for developmental change. Here we argue that understanding how visual working memory develops can shed new light onto the nature of representations. We present an alternative model, the Dynamic Field Theory (DFT), which can capture effects that have been previously attributed either to "slot" or "resource" explanations. The DFT includes a specific developmental mechanism to account for improvements in both resolution and capacity of visual working memory throughout childhood. Here we show how development in the DFT can account for different capacity estimates across feature types (i.e., color and shape). The current paper tests this account by comparing children's (3, 5, and 7 years of age) performance across different feature types. Results showed that capacity for colors increased faster over development than capacity for shapes. A second experiment confirmed this difference across feature types within subjects, but also showed that the difference can be attenuated by testing memory for less familiar colors. Model simulations demonstrate how developmental changes in connectivity within the model-purportedly arising through experience-can capture differences across feature types.

Exploration of a 'double-jeopardy' hypothesis within working memory profiles for children with specific language impairment.

PubMed

Briscoe, J; Rankin, P M

2009-01-01

Children with specific language impairment (SLI) often experience difficulties in the recall and repetition of verbal information. Archibald and Gathercole (2006) suggested that children with SLI are vulnerable across two separate components of a tripartite model of working memory (Baddeley and Hitch 1974). However, the hierarchical relationship between the 'slave' systems (temporary storage) and the central executive components places a particular challenge for interpreting working memory profiles within a tripartite model. This study aimed to examine whether a 'double-jeopardy' assumption is compatible with a hierarchical relationship between the phonological loop and central executive components of the working memory model in children with SLI. If a strong double-jeopardy assumption is valid for children with SLI, it was predicted that raw scores of working memory tests thought to tap phonological loop and central executive components of tripartite working memory would be lower than the scores of children matched for chronological age and those of children matched for language level, according to independent sources of constraint. In contrast, a hierarchical relationship would imply that a weakness in a slave component of working memory (the phonological loop) would also constrain performance on tests tapping a super-ordinate component (central executive). This locus of constraint would predict that scores of children with SLI on working memory tests that tap the central executive would be weaker relative to the scores of chronological age-matched controls only. Seven subtests of the Working Memory Test Battery for Children (Digit recall, Word recall, Non-word recall, Word matching, Listening recall, Backwards digit recall and Block recall; Pickering and Gathercole 2001) were administered to 14 children with SLI recruited via language resource bases and specialist schools, as well as two control groups matched on chronological age and vocabulary level, respectively. Mean group differences were ascertained by directly comparing raw scores on memory tests linked to different components of the tripartite model using a series of multivariate analyses. The majority of working memory scores of the SLI group were depressed relative to chronological age-matched controls, with the exception of spatial recall (block tapping) and word (order) matching tasks. Marked deficits in serial recall of words and digits were evident, with the SLI group scoring more poorly than the language-ability matched control group on these measures. Impairments of the SLI group on phonological loop tasks were robust, even when covariance with executive working memory scores was accounted for. There was no robust effect of group on complex working memory (central executive) tasks, despite a slight association between listening recall and phonological loop measures. A predominant feature of the working memory profile of SLI was a marked deficit on phonological loop tasks. Although scores on complex working memory tasks were also depressed, there was little evidence for a strong interpretation of double-jeopardy within working memory profiles for these children, rather these findings were consistent with an interpretation of a constraint on phonological loop for children with SLI that operated at all levels of a hierarchical tripartite model of working memory (Baddeley and Hitch 1974). These findings imply that low scores on complex working memory tasks alone do not unequivocally imply an independent deficit in central executive (domain-general) resources of working memory and should therefore be treated cautiously in a clinical context.

A randomised controlled trial investigating the benefits of adaptive working memory training for working memory capacity and attentional control in high worriers.

PubMed

Hotton, Matthew; Derakshan, Nazanin; Fox, Elaine

2018-01-01

The process of worry has been associated with reductions in working memory capacity and availability of resources necessary for efficient attentional control. This, in turn, can lead to escalating worry. Recent investigations into working memory training have shown improvements in attentional control and cognitive performance in high trait-anxious individuals and individuals with sub-clinical depression. The current randomised controlled trial investigated the effects of 15 days of adaptive n-back working memory training, or an active control task, on working memory capacity, attentional control and worry in a sample of high worriers. Pre-training, post-training and one-month follow-up measures of working memory capacity were assessed using a Change Detection task, while a Flanker task was used to assess attentional control. A breathing focus task was used as a behavioural measure of worry in addition to a number of self-report assessments of worry and anxiety. Overall there was no difference between the active training and the active control condition with both groups demonstrating similar improvements in working memory capacity and worry, post-training and at follow-up. However, training-related improvements on the n-back task were associated with gains in working memory capacity and reductions in worry symptoms in the active training condition. These results highlight the need for further research investigating the role of individual differences in working memory training. Copyright © 2017. Published by Elsevier Ltd.

Benefits of flexible prioritization in working memory can arise without costs.

PubMed

Myers, Nicholas E; Chekroud, Sammi R; Stokes, Mark G; Nobre, Anna C

2018-03-01

Most recent models conceptualize working memory (WM) as a continuous resource, divided up according to task demands. When an increasing number of items need to be remembered, each item receives a smaller chunk of the memory resource. These models predict that the allocation of attention to high-priority WM items during the retention interval should be a zero-sum game: improvements in remembering cued items come at the expense of uncued items because resources are dynamically transferred from uncued to cued representations. The current study provides empirical data challenging this model. Four precision retrocueing WM experiments assessed cued and uncued items on every trial. This permitted a test for trade-off of the memory resource. We found no evidence for trade-offs in memory across trials. Moreover, robust improvements in WM performance for cued items came at little or no cost to uncued items that were probed afterward, thereby increasing the net capacity of WM relative to neutral cueing conditions. An alternative mechanism of prioritization proposes that cued items are transferred into a privileged state within a response-gating bottleneck, in which an item uniquely controls upcoming behavior. We found evidence consistent with this alternative. When an uncued item was probed first, report of its orientation was biased away from the cued orientation to be subsequently reported. We interpret this bias as competition for behavioral control in the output-driving bottleneck. Other items in WM did not bias each other, making this result difficult to explain with a shared resource model. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Attention mediates the flexible allocation of visual working memory resources.

PubMed

Emrich, Stephen M; Lockhart, Holly A; Al-Aidroos, Naseem

2017-07-01

Though it is clear that it is impossible to store an unlimited amount of information in visual working memory (VWM), the limiting mechanisms remain elusive. While several models of VWM limitations exist, these typically characterize changes in performance as a function of the number of to-be-remembered items. Here, we examine whether changes in spatial attention could better account for VWM performance, independent of load. Across 2 experiments, performance was better predicted by the prioritization of memory items (i.e., attention) than by the number of items to be remembered (i.e., memory load). This relationship followed a power law, and held regardless of whether performance was assessed based on overall precision or any of 3 measures in a mixture model. Moreover, at large set sizes, even minimally attended items could receive a small proportion of resources, without any evidence for a discrete-capacity on the number of items that could be maintained in VWM. Finally, the observed data were best fit by a variable-precision model in which response error was related to the proportion of resources allocated to each item, consistent with a model of VWM in which performance is determined by the continuous allocation of attentional resources during encoding. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Obligatory encoding of task-irrelevant features depletes working memory resources.

PubMed

Marshall, Louise; Bays, Paul M

2013-02-18

Selective attention is often considered the "gateway" to visual working memory (VWM). However, the extent to which we can voluntarily control which of an object's features enter memory remains subject to debate. Recent research has converged on the concept of VWM as a limited commodity distributed between elements of a visual scene. Consequently, as memory load increases, the fidelity with which each visual feature is stored decreases. Here we used changes in recall precision to probe whether task-irrelevant features were encoded into VWM when individuals were asked to store specific feature dimensions. Recall precision for both color and orientation was significantly enhanced when task-irrelevant features were removed, but knowledge of which features would be probed provided no advantage over having to memorize both features of all items. Next, we assessed the effect an interpolated orientation-or color-matching task had on the resolution with which orientations in a memory array were stored. We found that the presence of orientation information in the second array disrupted memory of the first array. The cost to recall precision was identical whether the interfering features had to be remembered, attended to, or could be ignored. Therefore, it appears that storing, or merely attending to, one feature of an object is sufficient to promote automatic encoding of all its features, depleting VWM resources. However, the precision cost was abolished when the match task preceded the memory array. So, while encoding is automatic, maintenance is voluntary, allowing resources to be reallocated to store new visual information.

Interference due to shared features between action plans is influenced by working memory span.

PubMed

Fournier, Lisa R; Behmer, Lawrence P; Stubblefield, Alexandra M

2014-12-01

In this study, we examined the interactions between the action plans that we hold in memory and the actions that we carry out, asking whether the interference due to shared features between action plans is due to selection demands imposed on working memory. Individuals with low and high working memory spans learned arbitrary motor actions in response to two different visual events (A and B), presented in a serial order. They planned a response to the first event (A) and while maintaining this action plan in memory they then executed a speeded response to the second event (B). Afterward, they executed the action plan for the first event (A) maintained in memory. Speeded responses to the second event (B) were delayed when it shared an action feature (feature overlap) with the first event (A), relative to when it did not (no feature overlap). The size of the feature-overlap delay was greater for low-span than for high-span participants. This indicates that interference due to overlapping action plans is greater when fewer working memory resources are available, suggesting that this interference is due to selection demands imposed on working memory. Thus, working memory plays an important role in managing current and upcoming action plans, at least for newly learned tasks. Also, managing multiple action plans is compromised in individuals who have low versus high working memory spans.

Students Meet Wilfred Gordon: Helping Students with Special Needs Understand Their Memory

ERIC Educational Resources Information Center

Zambo, Debby M.

2006-01-01

Understanding how memory works is important for success in school, for "all" students. One way for teachers to help students with disabilities learn about memory is to use picture books and then learn strategies. Picture books are useful for students with disabilities because these resources have moved beyond a means to scaffold early literacy…

The Nature of Working Memory in Linguistic, Arithmetic and Spatial Integration Processes

ERIC Educational Resources Information Center

Fedorenko, Evelina; Gibson, Edward; Rohde, Douglas

2007-01-01

This paper reports the results of four dual-task experiments that were designed to determine the extent of domain-specificity of the verbal working memory resources used in linguistic integrations. To address this question, syntactic complexity was crossed in a 2x2 design with the complexity of a secondary task, which involved either (1)…

Neural basis for generalized quantifier comprehension.

PubMed

McMillan, Corey T; Clark, Robin; Moore, Peachie; Devita, Christian; Grossman, Murray

2005-01-01

Generalized quantifiers like "all cars" are semantically well understood, yet we know little about their neural representation. Our model of quantifier processing includes a numerosity device, operations that combine number elements and working memory. Semantic theory posits two types of quantifiers: first-order quantifiers identify a number state (e.g. "at least 3") and higher-order quantifiers additionally require maintaining a number state actively in working memory for comparison with another state (e.g. "less than half"). We used BOLD fMRI to test the hypothesis that all quantifiers recruit inferior parietal cortex associated with numerosity, while only higher-order quantifiers recruit prefrontal cortex associated with executive resources like working memory. Our findings showed that first-order and higher-order quantifiers both recruit right inferior parietal cortex, suggesting that a numerosity component contributes to quantifier comprehension. Moreover, only probes of higher-order quantifiers recruited right dorsolateral prefrontal cortex, suggesting involvement of executive resources like working memory. We also observed activation of thalamus and anterior cingulate that may be associated with selective attention. Our findings are consistent with a large-scale neural network centered in frontal and parietal cortex that supports comprehension of generalized quantifiers.

Attention and Visuospatial Working Memory Share the Same Processing Resources

PubMed Central

Feng, Jing; Pratt, Jay; Spence, Ian

2012-01-01

Attention and visuospatial working memory (VWM) share very similar characteristics; both have the same upper bound of about four items in capacity and they recruit overlapping brain regions. We examined whether both attention and VWM share the same processing resources using a novel dual-task costs approach based on a load-varying dual-task technique. With sufficiently large loads on attention and VWM, considerable interference between the two processes was observed. A further load increase on either process produced reciprocal increases in interference on both processes, indicating that attention and VWM share common resources. More critically, comparison among four experiments on the reciprocal interference effects, as measured by the dual-task costs, demonstrates no significant contribution from additional processing other than the shared processes. These results support the notion that attention and VWM share the same processing resources. PMID:22529826

Working memory capacity in generalized social phobia.

PubMed

Amir, Nader; Bomyea, Jessica

2011-05-01

Research suggests that understanding complex social cues depends on the availability of cognitive resources (e.g., Phillips, Channon, Tunstall, Hedenstrom, & Lyons, 2008). In spite of evidence suggesting that executive control functioning may impact anxiety (e.g., Eysenck, Derakshan, Santos, & Calvo, 2007), relatively few studies have examined working memory in individuals with generalized social phobia. Moreover, few studies have examined the role of threat-relevant content in working memory performance in clinically anxious populations. To this end, the present study assessed working memory capacity (WMC) in individuals with generalized social phobia and nonanxious controls using an operation span task with threat-relevant and neutral stimuli. Results revealed that nonanxious individuals demonstrated better WMC than individuals with generalized social phobia for neutral words but not for social threat words. Individuals with generalized social phobia demonstrated better WMC performance for threat words relative to neutral words. These results suggest that individuals with generalized social phobia may have relatively enhanced working memory performance for salient, socially relevant information. This enhanced working memory capacity for threat-relevant information may be the result of practice with this information in generalized social phobia.

Neural mechanisms of interference control in working memory capacity.

PubMed

Bomyea, Jessica; Taylor, Charles T; Spadoni, Andrea D; Simmons, Alan N

2018-02-01

The extent to which one can use cognitive resources to keep information in working memory is known to rely on (1) active maintenance of target representations and (2) downregulation of interference from irrelevant representations. Neurobiologically, the global capacity of working memory is thought to depend on the prefrontal and parietal cortices; however, the neural mechanisms involved in controlling interference specifically in working memory capacity tasks remain understudied. In this study, 22 healthy participants completed a modified complex working memory capacity task (Reading Span) with trials of varying levels of interference control demands while undergoing functional MRI. Neural activity associated with interference control demands was examined separately during encoding and recall phases of the task. Results suggested a widespread network of regions in the prefrontal, parietal, and occipital cortices, and the cingulate and cerebellum associated with encoding, and parietal and occipital regions associated with recall. Results align with prior findings emphasizing the importance of frontoparietal circuits for working memory performance, including the role of the inferior frontal gyrus, cingulate, occipital cortex, and cerebellum in regulation of interference demands. © 2017 Wiley Periodicals, Inc.

Age-Related Differences in Recognition Memory for Items and Associations: Contribution of Individual Differences in Working Memory and Metamemory

PubMed Central

Bender, Andrew R.; Raz, Naftali

2012-01-01

Ability to form new associations between unrelated items is particularly sensitive to aging, but the reasons for such differential vulnerability are unclear. In this study, we examined the role of objective and subjective factors (working memory and beliefs about memory strategies) on differential relations of age with recognition of items and associations. Healthy adults (N = 100, age 21 to 79) studied word pairs, completed item and association recognition tests, and rated the effectiveness of shallow (e.g., repetition) and deep (e.g., imagery or sentence generation) encoding strategies. Advanced age was associated with reduced working memory (WM) capacity and poorer associative recognition. In addition, reduced WM capacity, beliefs in the utility of ineffective encoding strategies, and lack of endorsement of effective ones were independently associated with impaired associative memory. Thus, maladaptive beliefs about memory in conjunction with reduced cognitive resources account in part for differences in associative memory commonly attributed to aging. PMID:22251381

Dopamine D1 signaling organizes network dynamics underlying working memory

PubMed Central

Roffman, Joshua L.; Tanner, Alexandra S.; Eryilmaz, Hamdi; Rodriguez-Thompson, Anais; Silverstein, Noah J.; Ho, New Fei; Nitenson, Adam Z.; Chonde, Daniel B.; Greve, Douglas N.; Abi-Dargham, Anissa; Buckner, Randy L.; Manoach, Dara S.; Rosen, Bruce R.; Hooker, Jacob M.; Catana, Ciprian

2016-01-01

Local prefrontal dopamine signaling supports working memory by tuning pyramidal neurons to task-relevant stimuli. Enabled by simultaneous positron emission tomography–magnetic resonance imaging (PET-MRI), we determined whether neuromodulatory effects of dopamine scale to the level of cortical networks and coordinate their interplay during working memory. Among network territories, mean cortical D1 receptor densities differed substantially but were strongly interrelated, suggesting cross-network regulation. Indeed, mean cortical D1 density predicted working memory–emergent decoupling of the frontoparietal and default networks, which respectively manage task-related and internal stimuli. In contrast, striatal D1 predicted opposing effects within these two networks but no between-network effects. These findings specifically link cortical dopamine signaling to network crosstalk that redirects cognitive resources to working memory, echoing neuromodulatory effects of D1 signaling on the level of cortical microcircuits. PMID:27386561

Focusing on attention: the effects of working memory capacity and load on selective attention.

PubMed

Ahmed, Lubna; de Fockert, Jan W

2012-01-01

Working memory (WM) is imperative for effective selective attention. Distractibility is greater under conditions of high (vs. low) concurrent working memory load (WML), and in individuals with low (vs. high) working memory capacity (WMC). In the current experiments, we recorded the flanker task performance of individuals with high and low WMC during low and high WML, to investigate the combined effect of WML and WMC on selective attention. In Experiment 1, distractibility from a distractor at a fixed distance from the target was greater when either WML was high or WMC was low, but surprisingly smaller when both WML was high and WMC low. Thus we observed an inverted-U relationship between reductions in WM resources and distractibility. In Experiment 2, we mapped the distribution of spatial attention as a function of WMC and WML, by recording distractibility across several target-to-distractor distances. The pattern of distractor effects across the target-to-distractor distances demonstrated that the distribution of the attentional window becomes dispersed as WM resources are limited. The attentional window was more spread out under high compared to low WML, and for low compared to high WMC individuals, and even more so when the two factors co-occurred (i.e., under high WML in low WMC individuals). The inverted-U pattern of distractibility effects in Experiment 1, replicated in Experiment 2, can thus be explained by differences in the spread of the attentional window as a function of WM resource availability. The current findings show that limitations in WM resources, due to either WML or individual differences in WMC, affect the spatial distribution of attention. The difference in attentional constraining between high and low WMC individuals demonstrated in the current experiments helps characterise the nature of previously established associations between WMC and controlled attention.

The sensory components of high-capacity iconic memory and visual working memory.

PubMed

Bradley, Claire; Pearson, Joel

2012-01-01

EARLY VISUAL MEMORY CAN BE SPLIT INTO TWO PRIMARY COMPONENTS: a high-capacity, short-lived iconic memory followed by a limited-capacity visual working memory that can last many seconds. Whereas a large number of studies have investigated visual working memory for low-level sensory features, much research on iconic memory has used more "high-level" alphanumeric stimuli such as letters or numbers. These two forms of memory are typically examined separately, despite an intrinsic overlap in their characteristics. Here, we used a purely sensory paradigm to examine visual short-term memory for 10 homogeneous items of three different visual features (color, orientation and motion) across a range of durations from 0 to 6 s. We found that the amount of information stored in iconic memory is smaller for motion than for color or orientation. Performance declined exponentially with longer storage durations and reached chance levels after ∼2 s. Further experiments showed that performance for the 10 items at 1 s was contingent on unperturbed attentional resources. In addition, for orientation stimuli, performance was contingent on the location of stimuli in the visual field, especially for short cue delays. Overall, our results suggest a smooth transition between an automatic, high-capacity, feature-specific sensory-iconic memory, and an effortful "lower-capacity" visual working memory.

Effects of emotional content on working memory capacity.

PubMed

Garrison, Katie E; Schmeichel, Brandon J

2018-02-13

Emotional events tend to be remembered better than neutral events, but emotional states and stimuli may also interfere with cognitive processes that underlie memory performance. The current study investigated the effects of emotional content on working memory capacity (WMC), which involves both short term storage and executive attention control. We tested competing hypotheses in a preregistered experiment (N = 297). The emotional enhancement hypothesis predicts that emotional stimuli attract attention and additional processing resources relative to neutral stimuli, thereby making it easier to encode and store emotional information in WMC. The emotional impairment hypothesis, by contrast, predicts that emotional stimuli interfere with attention control and the active maintenance of information in working memory. Participants completed a common measure of WMC (the operation span task; Turner, M. L., & Engle, R. W. [1989]. Is working memory capacity task dependent? Journal of Memory and Language, 28, 127-154) that included either emotional or neutral words. Results revealed that WMC was reduced for emotional words relative to neutral words, consistent with the emotional impairment hypothesis.

Reasoning and dyslexia: is visual memory a compensatory resource?

PubMed

Bacon, Alison M; Handley, Simon J

2014-11-01

Effective reasoning is fundamental to problem solving and achievement in education and employment. Protocol studies have previously suggested that people with dyslexia use reasoning strategies based on visual mental representations, whereas non-dyslexics use abstract verbal strategies. This research presents converging evidence from experimental and individual differences perspectives. In Experiment 1, dyslexic and non-dyslexic participants were similarly accurate on reasoning problems, but scores on a measure of visual memory ability only predicted reasoning accuracy for dyslexics. In Experiment 2, a secondary task loaded visual memory resources during concurrent reasoning. Dyslexics were significantly less accurate when reasoning under conditions of high memory load and showed reduced ability to subsequently recall the visual stimuli, suggesting that the memory and reasoning tasks were competing for the same visual cognitive resource. The results are consistent with an explanation based on limitations in the verbal and executive components of working memory in dyslexia and the use of compensatory visual strategies for reasoning. There are implications for cognitive activities that do not readily support visual thinking, whether in education, employment or less formal everyday settings. Copyright © 2014 John Wiley & Sons, Ltd.

Working memory and attentional bias on reinforcing efficacy of food.

PubMed

Carr, Katelyn A; Epstein, Leonard H

2017-09-01

Reinforcing efficacy of food, or the relationship between food prices and purchasing, is related to obesity status and energy intake in adults. Determining how to allocate resources for food is a decision making process influenced by executive functions. Attention to appetitive cues, as well as working memory capacity, or the ability to flexibly control attention while mentally retaining information, may be important executive functions involved in food purchasing decisions. In two studies, we examined how attention bias to food and working memory capacity are related to reinforcing efficacy of both high energy-dense and low energy-dense foods. The first study examined 48 women of varying body mass index (BMI) and found that the relationship between attentional processes and reinforcing efficacy was moderated by working memory capacity. Those who avoid food cues and had high working memory capacity had the lowest reinforcing efficacy, as compared to those with low working memory capacity. Study 2 systematically replicated the methods of study 1 with assessment of maintained attention in a sample of 48 overweight/obese adults. Results showed the relationship between maintained attention to food cues and reinforcing efficacy was moderated by working memory capacity. Those with a maintained attention to food and high working memory capacity had higher reinforcing efficacy than low working memory capacity individuals. These studies suggest working memory capacity moderated the relationship between different aspects of attention and food reinforcement. Understanding how decision making process are involved in reinforcing efficacy may help to identify future intervention targets. Copyright © 2017 Elsevier Ltd. All rights reserved.

Binding biological motion and visual features in working memory.

PubMed

Ding, Xiaowei; Zhao, Yangfan; Wu, Fan; Lu, Xiqian; Gao, Zaifeng; Shen, Mowei

2015-06-01

Working memory mechanisms for binding have been examined extensively in the last decade, yet few studies have explored bindings relating to human biological motion (BM). Human BM is the most salient and biologically significant kinetic information encountered in everyday life and is stored independently from other visual features (e.g., colors). The current study explored 3 critical issues of BM-related binding in working memory: (a) how many BM binding units can be retained in working memory, (b) whether involuntarily object-based binding occurs during BM binding, and (c) whether the maintenance of BM bindings in working memory requires attention above and beyond that needed to maintain the constituent dimensions. We isolated motion signals of human BM from non-BM sources by using point-light displays as to-be-memorized BM and presented the participants colored BM in a change detection task. We found that working memory capacity for BM-color bindings is rather low; only 1 or 2 BM-color bindings could be retained in working memory regardless of the presentation manners (Experiments 1-3). Furthermore, no object-based encoding took place for colored BM stimuli regardless of the processed dimensions (Experiments 4 and 5). Central executive attention contributes to the maintenance of BM-color bindings, yet maintaining BM bindings in working memory did not require more central attention than did maintaining the constituent dimensions in working memory (Experiment 6). Overall, these results suggest that keeping BM bindings in working memory is a fairly resource-demanding process, yet central executive attention does not play a special role in this cross-module binding. (c) 2015 APA, all rights reserved).

Neurophysiological capacity in a working memory task differentiates dependent from nondependent heavy drinkers and controls.

PubMed

Wesley, Michael J; Lile, Joshua A; Fillmore, Mark T; Porrino, Linda J

2017-06-01

Determining the neurobehavioral profiles that differentiate heavy drinkers who are and are not alcohol dependent will inform treatment efforts. Working memory is linked to substance use disorders and can serve as a representation of the demand placed on the neurophysiology associated with cognitive control. Behavior and brain activity (via fMRI) were recorded during an N-Back working memory task in controls (CTRL), nondependent heavy drinkers (A-ND) and dependent heavy drinkers (A-D). Typical and novel step-wise analyses examined profiles of working memory load and increasing task demand, respectively. Performance was significantly decreased in A-D during high working memory load (2-Back), compared to CTRL and A-ND. Analysis of brain activity during high load (0-Back vs. 2- Back) showed greater responses in the dorsal lateral and medial prefrontal cortices of A-D than CTRL, suggesting increased but failed compensation. The step-wise analysis revealed that the transition to Low Demand (0-Back to 1-Back) was associated with robust increases and decreases in cognitive control and default-mode brain regions, respectively, in A-D and A-ND but not CTRL. The transition to High Demand (1-Back to 2-Back) resulted in additional engagement of these networks in A-ND and CTRL, but not A-D. Heavy drinkers engaged working memory neural networks at lower demand than controls. As demand increased, nondependent heavy drinkers maintained control performance but relied on additional neurophysiological resources, and dependent heavy drinkers did not display further resource engagement and had poorer performance. These results support targeting these brain areas for treatment interventions. Copyright © 2017 Elsevier B.V. All rights reserved.

How do musical tonality and experience affect visual working memory?

PubMed

Yang, Hua; Lu, Jing; Gong, Diankun; Yao, Dezhong

2016-01-20

The influence of music on the human brain has continued to attract increasing attention from neuroscientists and musicologists. Currently, tonal music is widely present in people's daily lives; however, atonal music has gradually become an important part of modern music. In this study, we conducted two experiments: the first one tested for differences in perception of distractibility between tonal music and atonal music. The second experiment tested how tonal music and atonal music affect visual working memory by comparing musicians and nonmusicians who were placed in contexts with background tonal music, atonal music, and silence. They were instructed to complete a delay matching memory task. The results show that musicians and nonmusicians have different evaluations of the distractibility of tonal music and atonal music, possibly indicating that long-term training may lead to a higher auditory perception threshold among musicians. For the working memory task, musicians reacted faster than nonmusicians in all background music cases, and musicians took more time to respond in the tonal background music condition than in the other conditions. Therefore, our results suggest that for a visual memory task, background tonal music may occupy more cognitive resources than atonal music or silence for musicians, leaving few resources left for the memory task. Moreover, the musicians outperformed the nonmusicians because of the higher sensitivity to background music, which also needs a further longitudinal study to be confirmed.

Human short-term spatial memory: precision predicts capacity.

PubMed

Banta Lavenex, Pamela; Boujon, Valérie; Ndarugendamwo, Angélique; Lavenex, Pierre

2015-03-01

Here, we aimed to determine the capacity of human short-term memory for allocentric spatial information in a real-world setting. Young adults were tested on their ability to learn, on a trial-unique basis, and remember over a 1-min interval the location(s) of 1, 3, 5, or 7 illuminating pads, among 23 pads distributed in a 4m×4m arena surrounded by curtains on three sides. Participants had to walk to and touch the pads with their foot to illuminate the goal locations. In contrast to the predictions from classical slot models of working memory capacity limited to a fixed number of items, i.e., Miller's magical number 7 or Cowan's magical number 4, we found that the number of visited locations to find the goals was consistently about 1.6 times the number of goals, whereas the number of correct choices before erring and the number of errorless trials varied with memory load even when memory load was below the hypothetical memory capacity. In contrast to resource models of visual working memory, we found no evidence that memory resources were evenly distributed among unlimited numbers of items to be remembered. Instead, we found that memory for even one individual location was imprecise, and that memory performance for one location could be used to predict memory performance for multiple locations. Our findings are consistent with a theoretical model suggesting that the precision of the memory for individual locations might determine the capacity of human short-term memory for spatial information. Copyright © 2015 Elsevier Inc. All rights reserved.

Working memory accuracy for multiple targets is driven by reward expectation and stimulus contrast with different time-courses.

PubMed

Klink, P Christiaan; Jeurissen, Danique; Theeuwes, Jan; Denys, Damiaan; Roelfsema, Pieter R

2017-08-22

The richness of sensory input dictates that the brain must prioritize and select information for further processing and storage in working memory. Stimulus salience and reward expectations influence this prioritization but their relative contributions and underlying mechanisms are poorly understood. Here we investigate how the quality of working memory for multiple stimuli is determined by priority during encoding and later memory phases. Selective attention could, for instance, act as the primary gating mechanism when stimuli are still visible. Alternatively, observers might still be able to shift priorities across memories during maintenance or retrieval. To distinguish between these possibilities, we investigated how and when reward cues determine working memory accuracy and found that they were only effective during memory encoding. Previously learned, but currently non-predictive, color-reward associations had a similar influence, which gradually weakened without reinforcement. Finally, we show that bottom-up salience, manipulated through varying stimulus contrast, influences memory accuracy during encoding with a fundamentally different time-course than top-down reward cues. While reward-based effects required long stimulus presentation, the influence of contrast was strongest with brief presentations. Our results demonstrate how memory resources are distributed over memory targets and implicates selective attention as a main gating mechanism between sensory and memory systems.

Working memory, math performance, and math anxiety.

PubMed

Ashcraft, Mark H; Krause, Jeremy A

2007-04-01

The cognitive literature now shows how critically math performance depends on working memory, for any form of arithmetic and math that involves processes beyond simple memory retrieval. The psychometric literature is also very clear on the global consequences of mathematics anxiety. People who are highly math anxious avoid math: They avoid elective coursework in math, both in high school and college, they avoid college majors that emphasize math, and they avoid career paths that involve math. We go beyond these psychometric relationships to examine the cognitive consequences of math anxiety. We show how performance on a standardized math achievement test varies as a function of math anxiety, and that math anxiety compromises the functioning of working memory. High math anxiety works much like a dual task setting: Preoccupation with one's math fears and anxieties functions like a resource-demanding secondary task. We comment on developmental and educational factors related to math and working memory, and on factors that may contribute to the development of math anxiety.

Age differences and format effects in working memory.

PubMed

Foos, Paul W; Goolkasian, Paula

2010-07-01

Format effects refer to lower recall of printed words from working memory when compared to spoken words or pictures. These effects have been attributed to an attenuation of attention to printed words. The present experiment compares younger and older adults' recall of three or six items presented as pictures, spoken words, printed words, and alternating case WoRdS. The latter stimuli have been shown to increase attention to printed words and, thus, reduce format effects. The question of interest was whether these stimuli would also reduce format effects for older adults whose working memory capacity has fewer attentional resources to allocate. Results showed that older adults performed as well as younger adults with three items but less well with six and that format effects were reduced for both age groups, but more for young, when alternating case words were used. Other findings regarding executive control of working memory are discussed. The obtained differences support models of reduced capacity in older adult working memory.

Working memory capacity and visual-verbal cognitive load modulate auditory-sensory gating in the brainstem: toward a unified view of attention.

PubMed

Sörqvist, Patrik; Stenfelt, Stefan; Rönnberg, Jerker

2012-11-01

Two fundamental research questions have driven attention research in the past: One concerns whether selection of relevant information among competing, irrelevant, information takes place at an early or at a late processing stage; the other concerns whether the capacity of attention is limited by a central, domain-general pool of resources or by independent, modality-specific pools. In this article, we contribute to these debates by showing that the auditory-evoked brainstem response (an early stage of auditory processing) to task-irrelevant sound decreases as a function of central working memory load (manipulated with a visual-verbal version of the n-back task). Furthermore, individual differences in central/domain-general working memory capacity modulated the magnitude of the auditory-evoked brainstem response, but only in the high working memory load condition. The results support a unified view of attention whereby the capacity of a late/central mechanism (working memory) modulates early precortical sensory processing.

Study Modality and False Recall: The Influence of Resource Availability

PubMed Central

Smith, Rebekah E.; Engle, Randall W.

2010-01-01

False memories occur when individuals mistakenly report an event as having taken place when that event did not in fact occur. The DRM (Deese, 1959; Roediger & McDermott, 1995) paradigm provides an effective technique for creating and investigating false memories. In this paradigm participants study a list of words (e.g., SOUR, CANDY,…) that are highly associated to a non-presented critical item (e.g., SWEET). The study phase is followed by a test of memory for the study list words. Researchers typically find very high levels of false recall of the critical non-presented item. However, the likelihood of falsely remembering the non-presented critical items can be reduced by presenting studied associates visually rather than auditorally (e.g. Smith & Hunt, 1998). This is referred to as the modality effect in false memory. The current study investigated the role of resource availability in the expression of this modality effect in false recall. In Experiment 1 false recall was reduced in the visual study presentation condition relative to the auditory condition for participants with higher working memory capacity, but not for participants with lower working memory capacity. In Experiment 2 the effect of study modality on false recall was eliminated by the addition of a divided attention task at encoding. Both studies support the proposal that resource availability plays a role in the expression of the modality effect in the DRM paradigm (Smith, Lozito, & Bayen, 2005). PMID:20494859

Short-term memory and working memory in children with blindness: support for a domain general or domain specific system?

PubMed

Swanson, H Lee; Luxenberg, Diana

2009-05-01

The study explored the contribution of two component processes (phonological and executive) to blind children's memory performance. Children with blindness and sight were matched on gender, chronological age, and verbal intelligence and compared on measures of short-term memory (STM) and working memory (WM). Although the measures were highly correlated, the results from two experiments indicated that the blind children were superior to sighted children on measures of STM, but not on measures of WM. The results supported the notion that children with blindness have advantages on memory tasks that draw upon resources from the phonological loop. However, comparable performance between the ability groups on WM measures suggests there are domain specific aspects in the executive system.

Rapid Forgetting Results From Competition Over Time Between Items in Visual Working Memory

PubMed Central

2016-01-01

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. PMID:27668485

The Focus of Spatial Attention Determines the Number and Precision of Face Representations in Working Memory.

PubMed

Towler, John; Kelly, Maria; Eimer, Martin

2016-06-01

The capacity of visual working memory for faces is extremely limited, but the reasons for these limitations remain unknown. We employed event-related brain potential measures to demonstrate that individual faces have to be focally attended in order to be maintained in working memory, and that attention is allocated to only a single face at a time. When 2 faces have to be memorized simultaneously in a face identity-matching task, the focus of spatial attention during encoding predicts which of these faces can be successfully maintained in working memory and matched to a subsequent test face. We also show that memory representations of attended faces are maintained in a position-dependent fashion. These findings demonstrate that the limited capacity of face memory is directly linked to capacity limits of spatial attention during the encoding and maintenance of individual face representations. We suggest that the capacity and distribution of selective spatial attention is a dynamic resource that constrains the capacity and fidelity of working memory for faces. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

The stability of working memory: do previous tasks influence complex span?

PubMed

Healey, M Karl; Hasher, Lynn; Danilova, Elena

2011-11-01

Schmeichel (2007) reported that performing an initial task before completing a working memory span task can lower span scores and suggested that the effect was due to depleted cognitive resources. We showed that the detrimental effect of prior tasks depends on a match between the stimuli used in the span task and the preceding task. A task requiring participants to ignore words reduced performance on a subsequent word-based verbal span task but not on an arrow-based spatial span task. Ignoring arrows had the opposite pattern of effects: reducing performance on the spatial span task but not on the word-based span task. Finally, we showed that antisaccade, a nonverbal task that taxes domain-general processes implicated in working memory, did not influence subsequent performance of either a verbal or a spatial span task. Together these results suggest that while span is sensitive to prior tasks, that sensitivity does not stem from depleted resources. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

Regulation of Cognitive Resources During an N-Back Task in Youth-Onset Psychosis and Attention-Deficit/Hyperactivity Disorder (ADHD)

PubMed Central

Karatekin, Canan; Bingham, Christopher; White, Tonya

2009-01-01

The goals of the current study were to use behavioral and pupillary measures to examine working memory on a spatial n-back task in 8-20-year-olds with youth-onset psychosis or ADHD (Combined subtype) and healthy controls to determine the contribution of different attentional factors to spatial working memory impairments, and to examine if age-related changes in performance differed across groups. Although both clinical groups had lower perceptual sensitivity on both 0- and 1-back, there was no evidence of an impairment in spatial working memory or differential order effects on the 0-back. Instead, results suggest that both clinical groups had difficulty encoding the stimuli. They also appeared to have difficulty maintaining attention and/or readiness to respond, and, to a lesser extent, recruiting resources on a trial-to-trial basis. It is likely that these attentional problems prevented the clinical groups from encoding the stimuli effectively and contributed to their general performance deficits. PMID:19427339

Working Memory Integration Processes in Benign Childhood Epilepsy with Centrotemporal Spikes.

PubMed

Kárpáti, Judit; Donauer, Nándor; Somogyi, Eszter; Kónya, Anikó

2015-12-01

Benign epilepsy of childhood with centrotemporal spikes (BECTS) is the most frequent focal epilepsy in children; however, the pattern of affected memory processes remains controversial. Previous studies in BECTS imply deficits in complex working memory tasks, but not in simple modality-specific tasks. We studied working memory processes in children with BECTS by comparing performance in memory binding tasks of different complexities. We compared 17 children with BECTS (aged 6 to 13 years) to 17 healthy children matched for age, sex, and intelligence quotient. We measured spatial and verbal memory components separately and jointly on three single-binding tasks (binding of what and where; what and when; and where and when) and a combined-binding task (integration of what, where, and when). We also evaluated basic visuospatial memory functions with subtests of the Children's Memory Scale, and intellectual abilities with verbal tasks of the Wechsler Intelligence Scale for Children-Fourth Edition and the Raven Progressive Matrices. We found no difference between the BECTS and control groups in single-binding tasks; however, the children with BECTS performed significantly worse on the combined task, which included integration of spatial, verbal, and temporal information. We found no deficits in their intellectual abilities or basic visuospatial memory functions. Children with BECTS may have intact simple maintenance processes of working memory, but difficulty with high-level functions requiring attentional and executive resources. Our findings imply no specific memory dysfunction in BECTS, but suggest difficulties in integrating information within working memory, and possible frontal lobe disturbances.

Working Memory in the Prefrontal Cortex

PubMed Central

Funahashi, Shintaro

2017-01-01

The prefrontal cortex participates in a variety of higher cognitive functions. The concept of working memory is now widely used to understand prefrontal functions. Neurophysiological studies have revealed that stimulus-selective delay-period activity is a neural correlate of the mechanism for temporarily maintaining information in working memory processes. The central executive, which is the master component of Baddeley’s working memory model and is thought to be a function of the prefrontal cortex, controls the performance of other components by allocating a limited capacity of memory resource to each component based on its demand. Recent neurophysiological studies have attempted to reveal how prefrontal neurons achieve the functions of the central executive. For example, the neural mechanisms of memory control have been examined using the interference effect in a dual-task paradigm. It has been shown that this interference effect is caused by the competitive and overloaded recruitment of overlapping neural populations in the prefrontal cortex by two concurrent tasks and that the information-processing capacity of a single neuron is limited to a fixed level, can be flexibly allocated or reallocated between two concurrent tasks based on their needs, and enhances behavioral performance when its allocation to one task is increased. Further, a metamemory task requiring spatial information has been used to understand the neural mechanism for monitoring its own operations, and it has been shown that monitoring the quality of spatial information represented by prefrontal activity is an important factor in the subject's choice and that the strength of spatially selective delay-period activity reflects confidence in decision-making. Although further studies are needed to elucidate how the prefrontal cortex controls memory resource and supervises other systems, some important mechanisms related to the central executive have been identified. PMID:28448453

Domain-Specific Control of Selective Attention

PubMed Central

Lin, Szu-Hung; Yeh, Yei-Yu

2014-01-01

Previous research has shown that loading information on working memory affects selective attention. However, whether the load effect on selective attention is domain-general or domain-specific remains unresolved. The domain-general effect refers to the findings that load in one content (e.g. phonological) domain in working memory influences processing in another content (e.g., visuospatial) domain. Attentional control supervises selection regardless of information domain. The domain-specific effect refers to the constraint of influence only when maintenance and processing operate in the same domain. Selective attention operates in a specific content domain. This study is designed to resolve this controversy. Across three experiments, we manipulated the type of representation maintained in working memory and the type of representation upon which the participants must exert control to resolve conflict and select a target into the focus of attention. In Experiments 1a and 1b, participants maintained digits and nonverbalized objects, respectively, in working memory while selecting a target in a letter array. In Experiment 2, we presented auditory digits with a letter flanker task to exclude the involvement of resource competition within the same input modality. In Experiments 3a and 3b, we replaced the letter flanker task with an object flanker task while manipulating the memory load on object and digit representation, respectively. The results consistently showed that memory load modulated distractibility only when the stimuli of the two tasks were represented in the same domain. The magnitude of distractor interference was larger under high load than under low load, reflecting a lower efficacy of information prioritization. When the stimuli of the two tasks were represented in different domains, memory load did not modulate distractibility. Control of processing priority in selective attention demands domain-specific resources. PMID:24866977

Dopamine and the Management of Attentional Resources: Genetic Markers of Striatal D2 Dopamine Predict Individual Differences in the Attentional Blink

ERIC Educational Resources Information Center

Colzato, Lorenza S.; Slagter, Heleen A.; de Rover, Mischa; Hommel, Bernhard

2011-01-01

The attentional blink (AB)--a deficit in reporting the second of two target stimuli presented in close succession in a rapid sequence of distracters--has been related to processing limitations in working memory. Given that dopamine (DA) plays a crucial role working memory, the present study tested whether individual differences in the size of the…

The influence of linguistic and cognitive factors on the time course of verb-based implicit causality.

PubMed

Koornneef, Arnout; Dotlačil, Jakub; van den Broek, Paul; Sanders, Ted

2016-01-01

In three eye-tracking experiments the influence of the Dutch causal connective "want" (because) and the working memory capacity of readers on the usage of verb-based implicit causality was examined. Experiments 1 and 2 showed that although a causal connective is not required to activate implicit causality information during reading, effects of implicit causality surfaced more rapidly and were more pronounced when a connective was present in the discourse than when it was absent. In addition, Experiment 3 revealed that-in contrast to previous claims-the activation of implicit causality is not a resource-consuming mental operation. Moreover, readers with higher and lower working memory capacities behaved differently in a dual-task situation. Higher span readers were more likely to use implicit causality when they had all their working memory resources at their disposal. Lower span readers showed the opposite pattern as they were more likely to use the implicit causality cue in the case of an additional working memory load. The results emphasize that both linguistic and cognitive factors mediate the impact of implicit causality on text comprehension. The implications of these results are discussed in terms of the ongoing controversies in the literature-that is, the focusing-integration debate and the debates on the source of implicit causality.

The Sensory Components of High-Capacity Iconic Memory and Visual Working Memory

PubMed Central

Bradley, Claire; Pearson, Joel

2012-01-01

Early visual memory can be split into two primary components: a high-capacity, short-lived iconic memory followed by a limited-capacity visual working memory that can last many seconds. Whereas a large number of studies have investigated visual working memory for low-level sensory features, much research on iconic memory has used more “high-level” alphanumeric stimuli such as letters or numbers. These two forms of memory are typically examined separately, despite an intrinsic overlap in their characteristics. Here, we used a purely sensory paradigm to examine visual short-term memory for 10 homogeneous items of three different visual features (color, orientation and motion) across a range of durations from 0 to 6 s. We found that the amount of information stored in iconic memory is smaller for motion than for color or orientation. Performance declined exponentially with longer storage durations and reached chance levels after ∼2 s. Further experiments showed that performance for the 10 items at 1 s was contingent on unperturbed attentional resources. In addition, for orientation stimuli, performance was contingent on the location of stimuli in the visual field, especially for short cue delays. Overall, our results suggest a smooth transition between an automatic, high-capacity, feature-specific sensory-iconic memory, and an effortful “lower-capacity” visual working memory. PMID:23055993

The Role of Cognitive Load in Intentional Forgetting Using the Think/No-Think Task.

PubMed

Noreen, Saima; de Fockert, Jan W

2017-01-01

We investigated the role of cognitive control in intentional forgetting by manipulating working memory load during the think/no-think task. In two experiments, participants learned a series of cue-target word pairs and were asked to recall the target words associated with some cues or to avoid thinking about the target associated with other cues. In addition to this, participants also performed a modified version of the n-back task which required them to respond to the identity of a single target letter present in the currently presented cue word (n = 0 condition, low working memory load), and in either the previous cue word (n = 1 condition, high working memory load, Experiment 1) or the cue word presented two trials previously (n = 2 condition, high working memory load, Experiment 2). Participants' memory for the target words was subsequently tested using same and novel independent probes. In both experiments it was found that although participants were successful at forgetting on both the same and independent-probe tests in the low working memory load condition, they were only successful at forgetting on the same-probe test in the high working memory load condition. We argue that our findings suggest that the high load working memory task diverted attention from direct suppression and acted as an interference-based strategy. Thus, when cognitive resources are limited participants can switch between the strategies they use to prevent unwanted memories from coming to mind.

Slot-like capacity and resource-like coding in a neural model of multiple-item working memory.

PubMed

Standage, Dominic; Pare, Martin

2018-06-27

For the past decade, research on the storage limitations of working memory has been dominated by two fundamentally different hypotheses. On the one hand, the contents of working memory may be stored in a limited number of `slots', each with a fixed resolution. On the other hand, any number of items may be stored, but with decreasing resolution. These two hypotheses have been invaluable in characterizing the computational structure of working memory, but neither provides a complete account of the available experimental data, nor speaks to the neural basis of the limitations it characterizes. To address these shortcomings, we simulated a multiple-item working memory task with a cortical network model, the cellular resolution of which allowed us to quantify the coding fidelity of memoranda as a function of memory load, as measured by the discriminability, regularity and reliability of simulated neural spiking. Our simulations account for a wealth of neural and behavioural data from human and non-human primate studies, and they demonstrate that feedback inhibition lowers both capacity and coding fidelity. Because the strength of inhibition scales with the number of items stored by the network, increasing this number progressively lowers fidelity until capacity is reached. Crucially, the model makes specific, testable predictions for neural activity on multiple-item working memory tasks.

Top-down modulation: Bridging selective attention and working memory

PubMed Central

Gazzaley, Adam; Nobre, Anna C.

2012-01-01

Selective attention, the ability to focus our cognitive resources on information relevant to our goals, influences working memory (WM) performance. Indeed, attention and working memory are increasingly viewed as overlapping constructs. Here, we review recent evidence from human neurophysiological studies demonstrating that top-down modulation serves as a common neural mechanism underlying these two cognitive operations. The core features include activity modulation in stimulus-selective sensory cortices with concurrent engagement of prefrontal and parietal control regions that function as sources of top-down signals. Notably, top-down modulation is engaged during both stimulus-present and stimulus-absent stages of WM tasks, i.e., expectation of an ensuing stimulus to be remembered, selection and encoding of stimuli, maintenance of relevant information in mind and memory retrieval. PMID:22209601

Scalar implicatures: working memory and a comparison with only

PubMed Central

Marty, Paul P.; Chemla, Emmanuel

2013-01-01

A Scalar Implicature (SI) arises when the use of a relatively weak sentence (e.g., some politicians are corrupt) implies the denial of an alternative, stronger sentence (e.g., not all politicians are corrupt). The cognitive effort associated with the processing of SIs involves central memory resources (De Neys and Schaeken, 2007; Dieussaert et al., 2011; Marty et al., 2013). The goal of this study is to locate this previous result within the current psycholinguistic debate, and to understand at which level of SI processing these resources are specifically involved. Using a dual-task approach, we show that (1) tapping participant's memory resources interferes with the derivation of SIs, whereas (2) it does not affect the interpretation of sentences involving similar competition mechanisms between a sentence and potential alternatives through the use of only (e.g., only some politicians are corrupt). We explain how these findings suggest that the central memory resources are not involved in the core process at the source of SIs, and discuss how this difference between SIs and only bears on recent linguistic debates on the division of labor between grammar and pragmatics. PMID:23882230

Attention, Working Memory, and Grammaticality Judgment in Typical Young Adults

ERIC Educational Resources Information Center

Smith, Pamela A.

2011-01-01

Purpose: To examine resource allocation and sentence processing, this study examined the effects of auditory distraction on grammaticality judgment (GJ) of sentences varied by semantics (reversibility) and short-term memory requirements. Method: Experiment 1: Typical young adult females (N = 60) completed a whole-sentence GJ task in distraction…

Effects of working memory load on visual selective attention: behavioral and electrophysiological evidence.

PubMed

Pratt, Nikki; Willoughby, Adrian; Swick, Diane

2011-01-01

Working memory and attention interact in a way that enables us to focus on relevant items and maintain current goals. The influence of working memory on attention has been noted in several studies using dual task designs. Multitasking increases the demands on working memory and reduces the amount of resources available for cognitive control functions such as resolving stimulus conflict. However, few studies have investigated the temporal activation of the cortex while multitasking. The present study addresses the extent to which working memory load influences early (P1) and late (P300) attention-sensitive event-related potential components using a dual task paradigm. Participants performed an arrow flanker task alone (single task condition) or concurrently with a Sternberg memory task (dual task condition). In the flanker task, participants responded to the direction of a central arrow surrounded by congruent or incongruent arrows. In the dual task condition, participants were presented with a Sternberg task that consisted of either four or seven consonants to remember prior to a short block of flanker trials. Participants were slower and less accurate on incongruent versus congruent trials. Furthermore, accuracy on incongruent trials was reduced in both dual task conditions. Likewise, P300 amplitude to incongruent flanker stimuli decreased when working memory load increased. These findings suggest that interference from incongruent flankers was more difficult to suppress when working memory was taxed. In addition, P1 amplitude was diminished on all flanker trials in the dual task condition. This result indicates that top-down attentional control over early visual processing is diminished by increasing demands on working memory. Both the behavioral and electrophysiological results suggest that working memory is critical in maintaining attentional focus and resolving conflict.

Effects of Working Memory Load on Visual Selective Attention: Behavioral and Electrophysiological Evidence

PubMed Central

Pratt, Nikki; Willoughby, Adrian; Swick, Diane

2011-01-01

Working memory and attention interact in a way that enables us to focus on relevant items and maintain current goals. The influence of working memory on attention has been noted in several studies using dual task designs. Multitasking increases the demands on working memory and reduces the amount of resources available for cognitive control functions such as resolving stimulus conflict. However, few studies have investigated the temporal activation of the cortex while multitasking. The present study addresses the extent to which working memory load influences early (P1) and late (P300) attention-sensitive event-related potential components using a dual task paradigm. Participants performed an arrow flanker task alone (single task condition) or concurrently with a Sternberg memory task (dual task condition). In the flanker task, participants responded to the direction of a central arrow surrounded by congruent or incongruent arrows. In the dual task condition, participants were presented with a Sternberg task that consisted of either four or seven consonants to remember prior to a short block of flanker trials. Participants were slower and less accurate on incongruent versus congruent trials. Furthermore, accuracy on incongruent trials was reduced in both dual task conditions. Likewise, P300 amplitude to incongruent flanker stimuli decreased when working memory load increased. These findings suggest that interference from incongruent flankers was more difficult to suppress when working memory was taxed. In addition, P1 amplitude was diminished on all flanker trials in the dual task condition. This result indicates that top-down attentional control over early visual processing is diminished by increasing demands on working memory. Both the behavioral and electrophysiological results suggest that working memory is critical in maintaining attentional focus and resolving conflict. PMID:21716633

Does polycystic ovary syndrome affect cognition? A functional magnetic resonance imaging study exploring working memory.

PubMed

Soleman, Remi S; Kreukels, Baudewijntje P C; Veltman, Dick J; Cohen-Kettenis, Peggy T; Hompes, Peter G A; Drent, Madeleine L; Lambalk, Cornelis B

2016-05-01

To study effects of overexposure to androgens and subsequent antiandrogenic treatment on brain activity during working memory processes in women with polycystic ovary syndrome (PCOS). In this longitudinal study, working memory function was evaluated with the use of functional magnetic resonance imaging (MRI) in women with PCOS before and after antiandrogenic treatment. Department of reproductive medicine, university medical center. Fourteen women with PCOS and with hyperandrogenism and 20 healthy control women without any features of PCOS or other hormonal disorders. Antiandrogenic hormone treatment. Functional MRI response during a working memory task. At baseline women with PCOS showed more activation than the control group within the right superior parietal lobe and the inferior parietal lobe during task (all memory conditions). Task performance (speed and accuracy) did not differ between the groups. After antiandrogenic treatment the difference in overall brain activity between the groups disappeared and accuracy in the high memory load condition of the working memory task increased in women with PCOS. Women with PCOS may need additional neural resources during a working memory task compared with women without PCOS, suggesting less efficient executive functioning. This inefficiency may have effects on daily life functioning of women with PCOS. Antiandrogenic treatment appears to have a beneficial effect on this area of cognitive functioning. NTR2493. Copyright © 2016. Published by Elsevier Inc.

Visual short-term memory for oriented, colored objects.

PubMed

Shin, Hongsup; Ma, Wei Ji

2017-08-01

A central question in the study of visual short-term memory (VSTM) has been whether its basic units are objects or features. Most studies addressing this question have used change detection tasks in which the feature value before the change is highly discriminable from the feature value after the change. This approach assumes that memory noise is negligible, which recent work has shown not to be the case. Here, we investigate VSTM for orientation and color within a noisy-memory framework, using change localization with a variable magnitude of change. A specific consequence of the noise is that it is necessary to model the inference (decision) stage. We find that (a) orientation and color have independent pools of memory resource (consistent with classic results); (b) an irrelevant feature dimension is either encoded but ignored during decision-making, or encoded with low precision and taken into account during decision-making; and (c) total resource available in a given feature dimension is lower in the presence of task-relevant stimuli that are neutral in that feature dimension. We propose a framework in which feature resource comes both in packaged and in targeted form.

Fast and fragile: A new look at the automaticity of negation processing.

PubMed

Deutsch, Roland; Kordts-Freudinger, Robert; Gawronski, Bertram; Strack, Fritz

2009-01-01

Numerous studies suggest that processing verbal materials containing negations slows down cognition and makes it more error-prone. This suggests that processing negations affords relatively nonautomatic processes. The present research studied the role of two automaticity features (processing speed and resource dependency) for negation processing. In three experiments, we tested the impact of verbal negations on affective priming effects in the Affect Misattribution Paradigm. Going beyond previous work, the results indicate that negations can be processed unintentionally and quickly (Experiments 1 and 2). In Experiment 3, negations failed to qualify affective priming effects when participants' working memory was taxed by memorizing an eight-digit number. In sum, the experiments suggest that negations can be processed unintentionally, very quickly, but that they rely on working-memory resources.

Stereotype threat can both enhance and impair older adults' memory.

PubMed

Barber, Sarah J; Mather, Mara

2013-12-01

Negative stereotypes about aging can impair older adults' memory via stereotype threat; however, the mechanisms underlying this phenomenon are unclear. In two experiments, we tested competing predictions derived from two theoretical accounts of stereotype threat: executive-control interference and regulatory fit. Older adults completed a working memory test either under stereotype threat about age-related memory declines or not under such threat. Monetary incentives were manipulated such that recall led to gains or forgetting led to losses. The executive-control-interference account predicts that stereotype threat decreases the availability of executive-control resources and hence should impair working memory performance. The regulatory-fit account predicts that threat induces a prevention focus, which should impair performance when gains are emphasized but improve performance when losses are emphasized. Results were consistent only with the regulatory-fit account. Although stereotype threat significantly impaired older adults' working memory performance when remembering led to gains, it significantly improved performance when forgetting led to losses.

Modulation of selective attention by polarity-specific tDCS effects.

PubMed

Pecchinenda, Anna; Ferlazzo, Fabio; Lavidor, Michal

2015-02-01

Selective attention relies on working memory to maintain an attention set of task priorities. Consequently, selective attention is more efficient when working memory resources are not depleted. However, there is some evidence that distractors are processed even when working memory load is low. We used tDCS to assess whether boosting the activity of the Dorsolateral Prefrontal Cortex (DLPFC), involved in selective attention and working memory, would reduce interference from emotional distractors. Findings showed that anodal tDCS over the DLPFC was not sufficient to reduce interference from angry distractors. In contrast, cathodal tDCS over the DLPFC reduced interference from happy distractors. These findings show that altering the DLPFC activity is not sufficient to establish top-down control and increase selective attention efficiency. Although, when the neural signal in the DLPFC is altered by cathodal tDCS, interference from emotional distractors is reduced, leading to an improved performance. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Effects of Similarity on High-Level Visual Working Memory Processing.

PubMed

Yang, Li; Mo, Lei

2017-01-01

Similarity has been observed to have opposite effects on visual working memory (VWM) for complex images. How can these discrepant results be reconciled? To answer this question, we used a change-detection paradigm to test visual working memory performance for multiple real-world objects. We found that working memory for moderate similarity items was worse than that for either high or low similarity items. This pattern was unaffected by manipulations of stimulus type (faces vs. scenes), encoding duration (limited vs. self-paced), and presentation format (simultaneous vs. sequential). We also found that the similarity effects differed in strength in different categories (scenes vs. faces). These results suggest that complex real-world objects are represented using a centre-surround inhibition organization . These results support the category-specific cortical resource theory and further suggest that centre-surround inhibition organization may differ by category.

Visual Working Memory Cannot Trade Quantity for Quality.

PubMed

Ramaty, Ayelet; Luria, Roy

2018-01-01

Two main models have been proposed to describe how visual working memory (WM) allocates its capacity: the slot-model and the continuous resource-model. The purpose of the current study was to test a direct prediction of the resource model suggesting that WM can trade-off between the quantity and quality of the encoded information. Previous research reported equivocal results, with studies that failed to find such a trade-off and other studies that reported a trade-off. Following the design of previous studies, in Experiment 1 we replicated this trade-off, by presenting the memory array for 1200 ms. Experiment 2 failed to observe a trade-off between quantity and quality using a memory array interval of 300 ms (a standard interval for visual WM). Experiment 3 again failed to find this trade-off, when reinstating the 1200 ms memory array interval but adding an articulatory suppression manipulation. We argue that while participants can trade quantity for quality, this pattern depends on verbal encoding and transfer to long-term memory processes that were possible to perform only during the long retention interval. When these processes were eliminated, the trade-off disappeared. Thus, we didn't find any evidence that the trade-off between quantity for quality can occur within visual WM.

Symbiosis of executive and selective attention in working memory

PubMed Central

Vandierendonck, André

2014-01-01

The notion of working memory (WM) was introduced to account for the usage of short-term memory resources by other cognitive tasks such as reasoning, mental arithmetic, language comprehension, and many others. This collaboration between memory and other cognitive tasks can only be achieved by a dedicated WM system that controls task coordination. To that end, WM models include executive control. Nevertheless, other attention control systems may be involved in coordination of memory and cognitive tasks calling on memory resources. The present paper briefly reviews the evidence concerning the role of selective attention in WM activities. A model is proposed in which selective attention control is directly linked to the executive control part of the WM system. The model assumes that apart from storage of declarative information, the system also includes an executive WM module that represents the current task set. Control processes are automatically triggered when particular conditions in these modules are met. As each task set represents the parameter settings and the actions needed to achieve the task goal, it will depend on the specific settings and actions whether selective attention control will have to be shared among the active tasks. Only when such sharing is required, task performance will be affected by the capacity limits of the control system involved. PMID:25152723

Symbiosis of executive and selective attention in working memory.

PubMed

Vandierendonck, André

2014-01-01

The notion of working memory (WM) was introduced to account for the usage of short-term memory resources by other cognitive tasks such as reasoning, mental arithmetic, language comprehension, and many others. This collaboration between memory and other cognitive tasks can only be achieved by a dedicated WM system that controls task coordination. To that end, WM models include executive control. Nevertheless, other attention control systems may be involved in coordination of memory and cognitive tasks calling on memory resources. The present paper briefly reviews the evidence concerning the role of selective attention in WM activities. A model is proposed in which selective attention control is directly linked to the executive control part of the WM system. The model assumes that apart from storage of declarative information, the system also includes an executive WM module that represents the current task set. Control processes are automatically triggered when particular conditions in these modules are met. As each task set represents the parameter settings and the actions needed to achieve the task goal, it will depend on the specific settings and actions whether selective attention control will have to be shared among the active tasks. Only when such sharing is required, task performance will be affected by the capacity limits of the control system involved.

Bidirectional Frontoparietal Oscillatory Systems Support Working Memory.

PubMed

Johnson, Elizabeth L; Dewar, Callum D; Solbakk, Anne-Kristin; Endestad, Tor; Meling, Torstein R; Knight, Robert T

2017-06-19

The ability to represent and select information in working memory provides the neurobiological infrastructure for human cognition. For 80 years, dominant views of working memory have focused on the key role of prefrontal cortex (PFC) [1-8]. However, more recent work has implicated posterior cortical regions [9-12], suggesting that PFC engagement during working memory is dependent on the degree of executive demand. We provide evidence from neurological patients with discrete PFC damage that challenges the dominant models attributing working memory to PFC-dependent systems. We show that neural oscillations, which provide a mechanism for PFC to communicate with posterior cortical regions [13], independently subserve communications both to and from PFC-uncovering parallel oscillatory mechanisms for working memory. Fourteen PFC patients and 20 healthy, age-matched controls performed a working memory task where they encoded, maintained, and actively processed information about pairs of common shapes. In controls, the electroencephalogram (EEG) exhibited oscillatory activity in the low-theta range over PFC and directional connectivity from PFC to parieto-occipital regions commensurate with executive processing demands. Concurrent alpha-beta oscillations were observed over parieto-occipital regions, with directional connectivity from parieto-occipital regions to PFC, regardless of processing demands. Accuracy, PFC low-theta activity, and PFC → parieto-occipital connectivity were attenuated in patients, revealing a PFC-independent, alpha-beta system. The PFC patients still demonstrated task proficiency, which indicates that the posterior alpha-beta system provides sufficient resources for working memory. Taken together, our findings reveal neurologically dissociable PFC and parieto-occipital systems and suggest that parallel, bidirectional oscillatory systems form the basis of working memory. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Neural effects of cognitive control load on auditory selective attention

PubMed Central

Sabri, Merav; Humphries, Colin; Verber, Matthew; Liebenthal, Einat; Binder, Jeffrey R.; Mangalathu, Jain; Desai, Anjali

2014-01-01

Whether and how working memory disrupts or alters auditory selective attention is unclear. We compared simultaneous event-related potentials (ERP) and functional magnetic resonance imaging (fMRI) responses associated with task-irrelevant sounds across high and low working memory load in a dichotic-listening paradigm. Participants performed n-back tasks (1-back, 2-back) in one ear (Attend ear) while ignoring task-irrelevant speech sounds in the other ear (Ignore ear). The effects of working memory load on selective attention were observed at 130-210 msec, with higher load resulting in greater irrelevant syllable-related activation in localizer-defined regions in auditory cortex. The interaction between memory load and presence of irrelevant information revealed stronger activations primarily in frontal and parietal areas due to presence of irrelevant information in the higher memory load. Joint independent component analysis of ERP and fMRI data revealed that the ERP component in the N1 time-range is associated with activity in superior temporal gyrus and medial prefrontal cortex. These results demonstrate a dynamic relationship between working memory load and auditory selective attention, in agreement with the load model of attention and the idea of common neural resources for memory and attention. PMID:24946314

Control of Working Memory in Rhesus Monkeys (Macaca mulatta)

PubMed Central

Tu, Hsiao-Wei; Hampton, Robert R.

2014-01-01

Cognitive control is critical for efficiently using the limited resources in working memory. It is well established that humans use rehearsal to increase the probability of remembering needed information, but little is known in nonhumans, with some studies reporting the absence of active control and others subject to alternative explanations. We trained monkeys in a visual matching-to-sample paradigm with a post-sample memory cue. Monkeys either saw a remember cue that predicted the occurrence of a matching test that required memory for the sample, or a forget cue that predicted a discrimination test that did not require memory of the sample. Infrequent probe trials on which monkeys were given tests of the type not cued on that trial were used to assess whether memory was under cognitive control. Our procedures controlled for reward expectation and for the surprising nature of the probes. Monkeys matched less accurately after forget cues, while discrimination accuracy was equivalent in the two cue conditions. We also tested monkeys with lists of two consecutive sample images that shared the same cue. Again, memory for expected memory tests was superior to that on unexpected tests. Together these results show that monkeys cognitively control their working memory. PMID:25436219

Differential working memory correlates for implicit sequence performance in young and older adults.

PubMed

Bo, Jin; Jennett, S; Seidler, R D

2012-09-01

Our recent work has revealed that visuospatial working memory (VSWM) relates to the rate of explicit motor sequence learning (Bo and Seidler in J Neurophysiol 101:3116-3125, 2009) and implicit sequence performance (Bo et al. in Exp Brain Res 214:73-81, 2011a) in young adults (YA). Although aging has a detrimental impact on many cognitive functions, including working memory, older adults (OA) still rely on their declining working memory resources in an effort to optimize explicit motor sequence learning. Here, we evaluated whether age-related differences in VSWM and/or verbal working memory (VWM) performance relates to implicit performance change in the serial reaction time (SRT) sequence task in OA. Participants performed two computerized working memory tasks adapted from change detection working memory assessments (Luck and Vogel in Nature 390:279-281, 1997), an implicit SRT task and several neuropsychological tests. We found that, although OA exhibited an overall reduction in both VSWM and VWM, both OA and YA showed similar performance in the implicit SRT task. Interestingly, while VSWM and VWM were significantly correlated with each other in YA, there was no correlation between these two working memory scores in OA. In YA, the rate of SRT performance change (exponential fit to the performance curve) was significantly correlated with both VSWM and VWM, while in contrast, OA's performance was only correlated with VWM, and not VSWM. These results demonstrate differential reliance on VSWM and VWM for SRT performance between YA and OA. OA may utilize VWM to maintain optimized performance of second-order conditional sequences.

The impact of storage on processing: how is information maintained in working memory?

PubMed

Vergauwe, Evie; Camos, Valérie; Barrouillet, Pierre

2014-07-01

Working memory is typically defined as a system devoted to the simultaneous maintenance and processing of information. However, the interplay between these 2 functions is still a matter of debate in the literature, with views ranging from complete independence to complete dependence. The time-based resource-sharing model assumes that a central bottleneck constrains the 2 functions to alternate in such a way that maintenance activities postpone concurrent processing, with each additional piece of information to be maintained resulting in an additional postponement. Using different kinds of memoranda, we examined in a series of 7 experiments the effect of increasing memory load on different processing tasks. The results reveal that, insofar as attention is needed for maintenance, processing times linearly increase at a rate of about 50 ms per verbal or visuospatial memory item, suggesting a very fast refresh rate in working memory. Our results also show an asymmetry between verbal and spatial information, in that spatial information can solely rely on attention for its maintenance while verbal information can also rely on a domain-specific maintenance mechanism independent from attention. The implications for the functioning of working memory are discussed, with a specific focus on how information is maintained in working memory. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Rapid forgetting results from competition over time between items in visual working memory.

PubMed

Pertzov, Yoni; Manohar, Sanjay; Husain, Masud

2017-04-01

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).

Vocabulary learning in primary school children: working memory and long-term memory components.

PubMed

Morra, Sergio; Camba, Roberta

2009-10-01

The goal of this study was to investigate which working memory and long-term memory components predict vocabulary learning. We used a nonword learning paradigm in which 8- to 10-year-olds learned picture-nonword pairs. The nonwords varied in length (two vs. four syllables) and phonology (native sounding vs. including one Russian phoneme). Short, phonologically native nonwords were learned best, whereas learning long nonwords leveled off after a few presentation cycles. Linear structural equation analyses showed an influence of three constructs-phonological sensitivity, vocabulary knowledge, and central attentional resources (M capacity)-on nonword learning, but the extent of their contributions depended on specific characteristics of the nonwords to be learned. Phonological sensitivity predicted learning of all nonword types except short native nonwords, vocabulary predicted learning of only short native nonwords, and M capacity predicted learning of short nonwords but not long nonwords. The discussion considers three learning processes-effortful activation of phonological representations, lexical mediation, and passive associative learning-that use different cognitive resources and could be involved in learning different nonword types.

Focusing on Attention: The Effects of Working Memory Capacity and Load on Selective Attention

PubMed Central

Ahmed, Lubna; de Fockert, Jan W.

2012-01-01

Background Working memory (WM) is imperative for effective selective attention. Distractibility is greater under conditions of high (vs. low) concurrent working memory load (WML), and in individuals with low (vs. high) working memory capacity (WMC). In the current experiments, we recorded the flanker task performance of individuals with high and low WMC during low and high WML, to investigate the combined effect of WML and WMC on selective attention. Methodology/Principal Findings In Experiment 1, distractibility from a distractor at a fixed distance from the target was greater when either WML was high or WMC was low, but surprisingly smaller when both WML was high and WMC low. Thus we observed an inverted-U relationship between reductions in WM resources and distractibility. In Experiment 2, we mapped the distribution of spatial attention as a function of WMC and WML, by recording distractibility across several target-to-distractor distances. The pattern of distractor effects across the target-to-distractor distances demonstrated that the distribution of the attentional window becomes dispersed as WM resources are limited. The attentional window was more spread out under high compared to low WML, and for low compared to high WMC individuals, and even more so when the two factors co-occurred (i.e., under high WML in low WMC individuals). The inverted-U pattern of distractibility effects in Experiment 1, replicated in Experiment 2, can thus be explained by differences in the spread of the attentional window as a function of WM resource availability. Conclusions/Significance The current findings show that limitations in WM resources, due to either WML or individual differences in WMC, affect the spatial distribution of attention. The difference in attentional constraining between high and low WMC individuals demonstrated in the current experiments helps characterise the nature of previously established associations between WMC and controlled attention. PMID:22952636

What–where–when memory and encoding strategies in healthy aging

PubMed Central

2016-01-01

Older adults exhibit disproportionate impairments in memory for item-associations. These impairments may stem from an inability to self-initiate deep encoding strategies. The present study investigates this using the “treasure-hunt task”; a what–where–when style episodic memory test that requires individuals to “hide” items around complex scenes. This task separately assesses memory for item, location, and temporal order, as well as bound what–where–when information. The results suggest that older adults are able to ameliorate integration memory deficits by using self-initiated encoding strategies when these are externally located and therefore place reduced demands on working memory and attentional resources. PMID:26884230

Electrophysiological indices of altered working memory processes in long-term ecstasy users.

PubMed

Nulsen, Claire; Fox, Allison; Hammond, Geoff

2011-10-01

The aim of this study was to determine the effect of light long-term ecstasy consumption on verbal short-term and working memory and to identify the cognitive processes contributing to task performance. Electroencephalogram was recorded while ecstasy users (N = 11), polydrug users (N = 13), and non-users (N = 13) completed forward and backward serial recognition tasks designed to engage verbal short-term memory and verbal working memory, respectively. All three groups displayed significantly lower digit-backward span than digit-forward span with ecstasy users displaying the greatest difference. The parietally distributed P3b was significantly smaller in the digits backward task than in the digits forward task in non-ecstasy-using controls. Ecstasy users did not show the reduced P3b component in the backward task that was seen in both non-ecstasy-using control groups. Ecstasy users' performance was suppressed more by the concurrent processing demands of the working memory task than that of the non-ecstasy-using controls. Non-ecstasy-using controls showed differential event-related potential wave forms in the short-term and working memory tasks, and this pattern was not seen in the ecstasy users. This is consistent with a reduction in the cognitive resources allocated to processing in working memory in ecstasy users. Copyright © 2011 John Wiley & Sons, Ltd.

Modality dependence and intermodal transfer in the Corsi Spatial Sequence Task: Screen vs. Floor.

PubMed

Röser, Andrea; Hardiess, Gregor; Mallot, Hanspeter A

2016-07-01

Four versions of the Corsi Spatial Sequence Task (CSST) were tested in a complete within-subject design, investigating whether participants' performance depends on the modality of task presentation and reproduction that put different demands on spatial processing. Presentation of the sequence (encoding phase) and the reproduction (recall phase) were each carried out either on a computer screen or on the floor of a room, involving actual walking in the recall phase. Combinations of the two different encoding and recall procedures result in the modality conditions Screen-Screen, Screen-Floor, Floor-Screen, and Floor-Floor. Results show the expected decrease in performance with increasing sequence length, which is likely due to processing limitations of working memory. We also found differences in performance between the modality conditions indicating different involvements of spatial working memory processes. Participants performed best in the Screen-Screen modality condition. Floor-Screen and Floor-Floor modality conditions require additional working memory resources for reference frame transformation and spatial updating, respectively; the resulting impairment of the performance was about the same in these two conditions. Finally, the Screen-Floor modality condition requires both types of additional spatial demands and led to the poorest performance. Therefore, we suggest that besides the well-known spatial requirements of CSST, additional working memory resources are demanded in walking CSST supporting processes such as spatial updating, mental rotation, reference frame transformation, and the control of walking itself.

Self-Regulated Reading in Adulthood

PubMed Central

Stine-Morrow, Elizabeth A. L.; Soederberg Miller, Lisa M.; Gagne, Danielle D.; Hertzog, Christopher

2008-01-01

Younger and older adults read a series of passages of three different genres for an immediate assessment of text memory (measured by recall and true-false questions). Word-by-word reading times were measured and decomposed into components reflecting resource allocation to particular linguistic processes using regression. Allocation to word and textbase processes showed some consistency across the three text types and was predictive of memory performance. Older adults allocated more time to word and textbase processes than the young did, but showed enhanced contextual facilitation. Structural equation modeling showed that greater resource allocation to word processes was required among readers with relatively low working memory spans and poorer verbal ability, and that greater resource allocation to textbase processes was engendered by higher verbal ability. Results are discussed in terms of a model of self-regulated language processing suggesting that older readers may compensate for processing deficiencies through greater reliance on discourse context and on increases in resource allocation that are enabled through growth in crystallized ability. PMID:18361662

The persistence of thought: evidence for a role of working memory in the maintenance of task-unrelated thinking.

PubMed

Levinson, Daniel B; Smallwood, Jonathan; Davidson, Richard J

2012-04-01

Tasks that tax working memory (WM) have consistently been found to decrease mind wandering. These findings may indicate that maintenance of mind wandering requires WM resources, such that mind wandering cannot persist when WM resources are being consumed by a task. An alternative explanation for these findings, however, is that mind wandering persists without the support of WM but is nonetheless decreased during any demanding task because good task performance requires that attention be restricted from task-unrelated thought (TUT). The present study tested these two competing theories by investigating whether individuals with greater WM resources mind-wander more during an undemanding task, as would be predicted only by the theory that WM supports TUT. We found that individuals with higher WM capacity reported more TUT in undemanding tasks, which suggests that WM enables the maintenance of mind wandering.

Maternal scaffolding in a disadvantaged global context: The influence of working memory and cognitive capacities.

PubMed

Obradović, Jelena; Portilla, Ximena A; Tirado-Strayer, Nicole; Siyal, Saima; Rasheed, Muneera A; Yousafzai, Aisha K

2017-03-01

The current study focuses on maternal cognitive capacities as determinants of parenting in a highly disadvantaged global context, where children's experiences at home are often the 1st and only opportunity for learning and intellectual growth. In a large sample of 1,291 biological mothers of preschool-aged children in rural Pakistan, we examined the unique association of maternal working memory skills (independent of related cognitive capacities) with cognitively stimulating parenting behaviors. Path analysis revealed that directly assessed working memory, short-term memory, and verbal intelligence independently predicted greater levels of observed maternal scaffolding behaviors. Mothers from poorer families demonstrated lower levels of working memory, short-term memory, and verbal intelligence. However, mothers' participation in an early childhood parenting intervention that ended 2 years prior to this study contributed to greater levels of working memory skills and verbal intelligence. Further, all 3 domains of maternal cognitive capacity mediated the effect of family economic resources on maternal scaffolding, and verbal intelligence also mediated the effect of early parenting intervention exposure on maternal scaffolding. The study demonstrates the unique relevance of maternal working memory for scaffolding behaviors that required continuously monitoring the child's engagement, providing assistance, and minimizing external distractions. These results highlight the importance of directly targeting maternal cognitive capacities in poor women with little or no formal education, using a 2-generation intervention approach that includes activities known to promote parental executive functioning and literacy. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Age-related decline of precision and binding in visual working memory.

PubMed

Peich, Muy-Cheng; Husain, Masud; Bays, Paul M

2013-09-01

Working memory declines with normal aging, but the nature of this impairment is debated. Studies based on detecting changes to arrays of visual objects have identified two possible components to age-related decline: a reduction in the number of items that can be stored, or a deficit in maintaining the associations (bindings) between individual object features. However, some investigations have reported intact binding with aging, and specific deficits arising only in Alzheimer's disease. Here, using a recently developed continuous measure of recall fidelity, we tested the precision with which adults of different ages could reproduce from memory the orientation and color of a probed array item. The results reveal a further component of cognitive decline: an age-related decrease in the resolution with which visual information can be maintained in working memory. This increase in recall variability with age was strongest under conditions of greater memory load. Moreover, analysis of the distribution of errors revealed that older participants were more likely to incorrectly report one of the unprobed items in memory, consistent with an age-related increase in misbinding. These results indicate a systematic decline with age in working memory resources that can be recruited to store visual information. The paradigm presented here provides a sensitive index of both memory resolution and feature binding, with the potential for assessing their modulation by interventions. The findings have implications for understanding the mechanisms underpinning working memory deficits in both health and disease.

Age-Related Decline of Precision and Binding in Visual Working Memory

PubMed Central

2013-01-01

Working memory declines with normal aging, but the nature of this impairment is debated. Studies based on detecting changes to arrays of visual objects have identified two possible components to age-related decline: a reduction in the number of items that can be stored, or a deficit in maintaining the associations (bindings) between individual object features. However, some investigations have reported intact binding with aging, and specific deficits arising only in Alzheimer’s disease. Here, using a recently developed continuous measure of recall fidelity, we tested the precision with which adults of different ages could reproduce from memory the orientation and color of a probed array item. The results reveal a further component of cognitive decline: an age-related decrease in the resolution with which visual information can be maintained in working memory. This increase in recall variability with age was strongest under conditions of greater memory load. Moreover, analysis of the distribution of errors revealed that older participants were more likely to incorrectly report one of the unprobed items in memory, consistent with an age-related increase in misbinding. These results indicate a systematic decline with age in working memory resources that can be recruited to store visual information. The paradigm presented here provides a sensitive index of both memory resolution and feature binding, with the potential for assessing their modulation by interventions. The findings have implications for understanding the mechanisms underpinning working memory deficits in both health and disease. PMID:23978008

Food Cravings Consume Limited Cognitive Resources

ERIC Educational Resources Information Center

Kemps, Eva; Tiggemann, Marika; Grigg, Megan

2008-01-01

Using Tiffany's (1990) cognitive model of drug use and craving as a theoretical basis, the present experiments investigated whether cravings for food expend limited cognitive resources. Cognitive performance was assessed by simple reaction time (Experiment 1) and an established measure of working memory capacity, the operation span task…

Brain and effort: brain activation and effort-related working memory in healthy participants and patients with working memory deficits.

PubMed

Engström, Maria; Landtblom, Anne-Marie; Karlsson, Thomas

2013-01-01

Despite the interest in the neuroimaging of working memory, little is still known about the neurobiology of complex working memory in tasks that require simultaneous manipulation and storage of information. In addition to the central executive network, we assumed that the recently described salience network [involving the anterior insular cortex (AIC) and the anterior cingulate cortex (ACC)] might be of particular importance to working memory tasks that require complex, effortful processing. Healthy participants (n = 26) and participants suffering from working memory problems related to the Kleine-Levin syndrome (KLS) (a specific form of periodic idiopathic hypersomnia; n = 18) participated in the study. Participants were further divided into a high- and low-capacity group, according to performance on a working memory task (listening span). In a functional magnetic resonance imaging (fMRI) study, participants were administered the reading span complex working memory task tapping cognitive effort. The fMRI-derived blood oxygen level dependent (BOLD) signal was modulated by (1) effort in both the central executive and the salience network and (2) capacity in the salience network in that high performers evidenced a weaker BOLD signal than low performers. In the salience network there was a dichotomy between the left and the right hemisphere; the right hemisphere elicited a steeper increase of the BOLD signal as a function of increasing effort. There was also a stronger functional connectivity within the central executive network because of increased task difficulty. The ability to allocate cognitive effort in complex working memory is contingent upon focused resources in the executive and in particular the salience network. Individual capacity during the complex working memory task is related to activity in the salience (but not the executive) network so that high-capacity participants evidence a lower signal and possibly hence a larger dynamic response.

Brain and effort: brain activation and effort-related working memory in healthy participants and patients with working memory deficits

PubMed Central

Engström, Maria; Landtblom, Anne-Marie; Karlsson, Thomas

2013-01-01

Despite the interest in the neuroimaging of working memory, little is still known about the neurobiology of complex working memory in tasks that require simultaneous manipulation and storage of information. In addition to the central executive network, we assumed that the recently described salience network [involving the anterior insular cortex (AIC) and the anterior cingulate cortex (ACC)] might be of particular importance to working memory tasks that require complex, effortful processing. Method: Healthy participants (n = 26) and participants suffering from working memory problems related to the Kleine–Levin syndrome (KLS) (a specific form of periodic idiopathic hypersomnia; n = 18) participated in the study. Participants were further divided into a high- and low-capacity group, according to performance on a working memory task (listening span). In a functional magnetic resonance imaging (fMRI) study, participants were administered the reading span complex working memory task tapping cognitive effort. Principal findings: The fMRI-derived blood oxygen level dependent (BOLD) signal was modulated by (1) effort in both the central executive and the salience network and (2) capacity in the salience network in that high performers evidenced a weaker BOLD signal than low performers. In the salience network there was a dichotomy between the left and the right hemisphere; the right hemisphere elicited a steeper increase of the BOLD signal as a function of increasing effort. There was also a stronger functional connectivity within the central executive network because of increased task difficulty. Conclusion: The ability to allocate cognitive effort in complex working memory is contingent upon focused resources in the executive and in particular the salience network. Individual capacity during the complex working memory task is related to activity in the salience (but not the executive) network so that high-capacity participants evidence a lower signal and possibly hence a larger dynamic response. PMID:23616756

Working-Class Women Study Social Science Degrees: Remembering Enablers and Detractors

ERIC Educational Resources Information Center

Fraser, Heather; Michell, Dee; Beddoe, Liz; Jarldorn, Michele

2016-01-01

In this article, we report on a feminist memory work project conducted with 11 working-class women in Australia. Participants responded to the question: "what helps and hinders working-class women study social science degrees?" The women confirmed that to succeed at university, they needed opportunities, resources, support and…

Fine-grained versus categorical: Pupil size differentiates between strategies for spatial working memory performance.

PubMed

Starc, Martina; Anticevic, Alan; Repovš, Grega

2017-05-01

Pupillometry provides an accessible option to track working memory processes with high temporal resolution. Several studies showed that pupil size increases with the number of items held in working memory; however, no study has explored whether pupil size also reflects the quality of working memory representations. To address this question, we used a spatial working memory task to investigate the relationship of pupil size with spatial precision of responses and indicators of reliance on generalized spatial categories. We asked 30 participants (15 female, aged 19-31) to remember the position of targets presented at various locations along a hidden radial grid. After a delay, participants indicated the remembered location with a high-precision joystick providing a parametric measure of trial-to-trial accuracy. We recorded participants' pupil dilations continuously during task performance. Results showed a significant relation between pupil dilation during preparation/early encoding and the precision of responses, possibly reflecting the attentional resources devoted to memory encoding. In contrast, pupil dilation at late maintenance and response predicted larger shifts of responses toward prototypical locations, possibly reflecting larger reliance on categorical representation. On an intraindividual level, smaller pupil dilations during encoding predicted larger dilations during late maintenance and response. On an interindividual level, participants relying more on categorical representation also produced larger precision errors. The results confirm the link between pupil size and the quality of spatial working memory representation. They suggest compensatory strategies of spatial working memory performance-loss of precise spatial representation likely increases reliance on generalized spatial categories. © 2017 Society for Psychophysiological Research.

Study modality and false recall.

PubMed

Smith, Rebekah E; Engle, Randall W

2011-01-01

False memories occur when individuals mistakenly report an event as having taken place when that event did not in fact occur. The DRM (Deese, 1959; Roediger & McDermott, 1995) paradigm provides an effective technique for creating and investigating false memories. In this paradigm participants study a list of words (e.g., SOUR, CANDY,…) that are highly associated to a non-presented critical item (e.g., SWEET). The study phase is followed by a test of memory for the study list words. Researchers typically find very high levels of false recall of the critical non-presented item. However, the likelihood of falsely remembering the non-presented critical items can be reduced by presenting studied associates visually rather than auditorally (e.g., Smith & Hunt, 1998). This is referred to as the modality effect in false memory. The current study investigated the role of resource availability in the expression of this modality effect in false recall. In Experiment 1 false recall was reduced in the visual study presentation condition relative to the auditory condition for participants with higher working memory capacity, but not for participants with lower working memory capacity. In Experiment 2 the effect of study modality on false recall was eliminated by the addition of a divided attention task at encoding. Both studies support the proposal that resource availability plays a role in the expression of the modality effect in the DRM paradigm (Smith, Lozito, & Bayen, 2005).

Negative emotional experiences arouse rumination and affect working memory capacity.

PubMed

Curci, Antonietta; Lanciano, Tiziana; Soleti, Emanuela; Rimé, Bernard

2013-10-01

Following an emotional experience, individuals are confronted with the persistence of ruminative thoughts that disturb the undertaking of other activities. In the present study, we experimentally tested the idea that experiencing a negative emotion triggers a ruminative process that drains working memory (WM) resources normally devoted to other tasks. Undergraduate participants of high versus low WM capacity were administered the operation-word memory span test (OSPAN) as a measure of availability of WM resources preceding and following the presentation of negative emotional versus neutral material. Rumination was assessed immediately after the second OSPAN session and at a 24-hr delay. Results showed that both the individual's WM capacity and the emotional valence of the material influenced WM performance and the persistence of ruminative thoughts. Following the experimental induction, rumination mediated the relationship between the negative emotional state and the concomitant WM performance. Based on these results, we argue that ruminative processes deplete WM resources, making them less available for concurrent tasks; in addition, rumination tends to persist over time. These findings have implications for the theoretical modeling of the long-term effects of emotions in both daily life and clinical contexts.

Causes and consequences of limitations in visual working memory

PubMed Central

Zokaei, Nahid; Husain, Masud

2016-01-01

Recent methodological and conceptual advances have led to a fundamental reappraisal of the nature of visual working memory (WM). A large corpus of evidence now suggests that there might not be a hard limit on the number of items that can be stored. Instead, WM may be better captured by a highly limited––but flexible––resource model. More resource can be allocated to prioritized items but, crucially, at a cost of reduced recall precision for other stored items. Expectations may modulate resource distribution, for example, through neural oscillations in the alpha band increasing inhibition of irrelevant cortical regions. Our understanding of the neural architecture of WM is also undergoing radical revision. Whereas the prefrontal cortex has previously dominated research endeavors, other cortical regions, such as early visual areas, are now considered to make an essential contribution, for example holding one or more items in a privileged state or “focus of attention” within WM. By contrast, the striatum is increasingly viewed as crucial in determining why and how items are gated into memory, while the hippocampus, it has controversially been argued, might be critical in the formation of temporally resilient conjunctions across features of stored items in WM. PMID:26773268

Neural effects of cognitive control load on auditory selective attention.

PubMed

Sabri, Merav; Humphries, Colin; Verber, Matthew; Liebenthal, Einat; Binder, Jeffrey R; Mangalathu, Jain; Desai, Anjali

2014-08-01

Whether and how working memory disrupts or alters auditory selective attention is unclear. We compared simultaneous event-related potentials (ERP) and functional magnetic resonance imaging (fMRI) responses associated with task-irrelevant sounds across high and low working memory load in a dichotic-listening paradigm. Participants performed n-back tasks (1-back, 2-back) in one ear (Attend ear) while ignoring task-irrelevant speech sounds in the other ear (Ignore ear). The effects of working memory load on selective attention were observed at 130-210ms, with higher load resulting in greater irrelevant syllable-related activation in localizer-defined regions in auditory cortex. The interaction between memory load and presence of irrelevant information revealed stronger activations primarily in frontal and parietal areas due to presence of irrelevant information in the higher memory load. Joint independent component analysis of ERP and fMRI data revealed that the ERP component in the N1 time-range is associated with activity in superior temporal gyrus and medial prefrontal cortex. These results demonstrate a dynamic relationship between working memory load and auditory selective attention, in agreement with the load model of attention and the idea of common neural resources for memory and attention. Copyright © 2014 Elsevier Ltd. All rights reserved.

Is less really more: Does a prefrontal efficiency genotype actually confer better performance when working memory becomes difficult?

PubMed

Ihne, Jessica L; Gallagher, Natalie M; Sullivan, Marie; Callicott, Joseph H; Green, Adam E

2016-01-01

Perhaps the most widely studied effect to emerge from the combination of neuroimaging and human genetics is the association of the COMT-Val(108/158)Met polymorphism with prefrontal activity during working memory. COMT-Val is a putative risk factor in schizophrenia, which is characterized by disordered prefrontal function. Work in healthy populations has sought to characterize mechanisms by which the valine (Val) allele may lead to disadvantaged prefrontal cognition. Lower activity in methionine (Met) carriers has been interpreted as advantageous neural efficiency. Notably, however, studies reporting COMT effects on neural efficiency have generally not reported working memory performance effects. Those studies have employed relatively low/easy working memory loads. Higher loads are known to elicit individual differences in working memory performance that are not visible at lower loads. If COMT-Met confers greater neural efficiency when working memory is easy, a reasonable prediction is that Met carriers will be better able to cope with increasing demand for neural resources when working memory becomes difficult. To our knowledge, this prediction has thus far gone untested. Here, we tested performance on three working memory tasks. Performance on each task was measured at multiple levels of load/difficulty, including loads more demanding than those used in prior studies. We found no genotype-by-load interactions or main effects of COMT genotype on accuracy or reaction time. Indeed, even testing for performance differences at each load of each task failed to find a single significant effect of COMT genotype. Thus, even if COMT genotype has the effects on prefrontal efficiency that prior work has suggested, such effects may not directly impact high-load working memory ability. The present findings accord with previous evidence that behavioral effects of COMT are small or nonexistent and, more broadly, with a growing consensus that substantial effects on phenotype will not emerge from candidate gene studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Neural substrate of initiation of cross-modal working memory retrieval.

PubMed

Zhang, Yangyang; Hu, Yang; Guan, Shuchen; Hong, Xiaolong; Wang, Zhaoxin; Li, Xianchun

2014-01-01

Cross-modal working memory requires integrating stimuli from different modalities and it is associated with co-activation of distributed networks in the brain. However, how brain initiates cross-modal working memory retrieval remains not clear yet. In the present study, we developed a cued matching task, in which the necessity for cross-modal/unimodal memory retrieval and its initiation time were controlled by a task cue appeared in the delay period. Using functional magnetic resonance imaging (fMRI), significantly larger brain activations were observed in the left lateral prefrontal cortex (l-LPFC), left superior parietal lobe (l-SPL), and thalamus in the cued cross-modal matching trials (CCMT) compared to those in the cued unimodal matching trials (CUMT). However, no significant differences in the brain activations prior to task cue were observed for sensory stimulation in the l-LPFC and l-SPL areas. Although thalamus displayed differential responses to the sensory stimulation between two conditions, the differential responses were not the same with responses to the task cues. These results revealed that the frontoparietal-thalamus network participated in the initiation of cross-modal working memory retrieval. Secondly, the l-SPL and thalamus showed differential activations between maintenance and working memory retrieval, which might be associated with the enhanced demand for cognitive resources.

Effects of Age and Working Memory Capacity on Speech Recognition Performance in Noise Among Listeners With Normal Hearing.

PubMed

Gordon-Salant, Sandra; Cole, Stacey Samuels

2016-01-01

This study aimed to determine if younger and older listeners with normal hearing who differ on working memory span perform differently on speech recognition tests in noise. Older adults typically exhibit poorer speech recognition scores in noise than younger adults, which is attributed primarily to poorer hearing sensitivity and more limited working memory capacity in older than younger adults. Previous studies typically tested older listeners with poorer hearing sensitivity and shorter working memory spans than younger listeners, making it difficult to discern the importance of working memory capacity on speech recognition. This investigation controlled for hearing sensitivity and compared speech recognition performance in noise by younger and older listeners who were subdivided into high and low working memory groups. Performance patterns were compared for different speech materials to assess whether or not the effect of working memory capacity varies with the demands of the specific speech test. The authors hypothesized that (1) normal-hearing listeners with low working memory span would exhibit poorer speech recognition performance in noise than those with high working memory span; (2) older listeners with normal hearing would show poorer speech recognition scores than younger listeners with normal hearing, when the two age groups were matched for working memory span; and (3) an interaction between age and working memory would be observed for speech materials that provide contextual cues. Twenty-eight older (61 to 75 years) and 25 younger (18 to 25 years) normal-hearing listeners were assigned to groups based on age and working memory status. Northwestern University Auditory Test No. 6 words and Institute of Electrical and Electronics Engineers sentences were presented in noise using an adaptive procedure to measure the signal-to-noise ratio corresponding to 50% correct performance. Cognitive ability was evaluated with two tests of working memory (Listening Span Test and Reading Span Test) and two tests of processing speed (Paced Auditory Serial Addition Test and The Letter Digit Substitution Test). Significant effects of age and working memory capacity were observed on the speech recognition measures in noise, but these effects were mediated somewhat by the speech signal. Specifically, main effects of age and working memory were revealed for both words and sentences, but the interaction between the two was significant for sentences only. For these materials, effects of age were observed for listeners in the low working memory groups only. Although all cognitive measures were significantly correlated with speech recognition in noise, working memory span was the most important variable accounting for speech recognition performance. The results indicate that older adults with high working memory capacity are able to capitalize on contextual cues and perform as well as young listeners with high working memory capacity for sentence recognition. The data also suggest that listeners with normal hearing and low working memory capacity are less able to adapt to distortion of speech signals caused by background noise, which requires the allocation of more processing resources to earlier processing stages. These results indicate that both younger and older adults with low working memory capacity and normal hearing are at a disadvantage for recognizing speech in noise.

Only "efficient" emotional stimuli affect the content of working memory during free-recollection from natural scenes.

PubMed

Buttafuoco, Arianna; Pedale, Tiziana; Buchanan, Tony W; Santangelo, Valerio

2018-02-01

Emotional events are thought to have privileged access to attention and memory, consuming resources needed to encode competing emotionally neutral stimuli. However, it is not clear whether this detrimental effect is automatic or depends on the successful maintenance of the specific emotional object within working memory. Here, participants viewed everyday scenes including an emotional object among other neutral objects followed by a free-recollection task. Results showed that emotional objects-irrespective of their perceptual saliency-were recollected more often than neutral objects. The probability of being recollected increased as a function of the arousal of the emotional objects, specifically for negative objects. Successful recollection of emotional objects (positive or negative) from a scene reduced the overall number of recollected neutral objects from the same scene. This indicates that only emotional stimuli that are efficient in grabbing (and then consuming) available attentional resources play a crucial role during the encoding of competing information, with a subsequent bias in the recollection of neutral representations.

Working memory predicts children's analogical reasoning.

PubMed

Simms, Nina K; Frausel, Rebecca R; Richland, Lindsey E

2018-02-01

Analogical reasoning is the cognitive skill of drawing relationships between representations, often between prior knowledge and new representations, that allows for bootstrapping cognitive and language development. Analogical reasoning proficiency develops substantially during childhood, although the mechanisms underlying this development have been debated, with developing cognitive resources as one proposed mechanism. We explored the role of executive function (EF) in supporting children's analogical reasoning development, with the goal of determining whether predicted aspects of EF were related to analogical development at the level of individual differences. We assessed 5- to 11-year-old children's working memory, inhibitory control, and cognitive flexibility using measures from the National Institutes of Health Toolbox Cognition battery. Individual differences in children's working memory best predicted performance on an analogical mapping task, even when controlling for age, suggesting a fundamental interrelationship between analogical reasoning and working memory development. These findings underscore the need to consider cognitive capacities in comprehensive theories of children's reasoning development. Copyright © 2017 Elsevier Inc. All rights reserved.

Efficiency at rest: magnetoencephalographic resting-state connectivity and individual differences in verbal working memory.

PubMed

del Río, David; Cuesta, Pablo; Bajo, Ricardo; García-Pacios, Javier; López-Higes, Ramón; del-Pozo, Francisco; Maestú, Fernando

2012-11-01

Inter-individual differences in cognitive performance are based on an efficient use of task-related brain resources. However, little is known yet on how these differences might be reflected on resting-state brain networks. Here we used Magnetoencephalography resting-state recordings to assess the relationship between a behavioral measurement of verbal working memory and functional connectivity as measured through Mutual Information. We studied theta (4-8 Hz), low alpha (8-10 Hz), high alpha (10-13 Hz), low beta (13-18 Hz) and high beta (18-30 Hz) frequency bands. A higher verbal working memory capacity was associated with a lower mutual information in the low alpha band, prominently among right-anterior and left-lateral sensors. The results suggest that an efficient brain organization in the domain of verbal working memory might be related to a lower resting-state functional connectivity across large-scale brain networks possibly involving right prefrontal and left perisylvian areas. Copyright © 2012 Elsevier B.V. All rights reserved.

Working memory load reduces the late positive potential and this effect is attenuated with increasing anxiety.

PubMed

MacNamara, Annmarie; Ferri, Jamie; Hajcak, Greg

2011-09-01

Emotion regulation decreases the processing of arousing stimuli, as indexed by the late positive potential (LPP), an electrocortical component that varies in amplitude with emotional arousal. Emotion regulation increases activity in the prefrontal areas associated with cognitive control, including the dosolateral prefrontal cortex (DLPFC). The present study manipulated working memory load, known to activate the DLPFC, and recorded the LPP elicited by aversive and neutral IAPS pictures presented during the retention interval. The LPP was larger on low-load compared to high-load trials, and on trials with aversive compared to neutral pictures. These LPP data suggest that emotional content and working memory load have opposing effects on attention to distracting stimuli. State anxiety was associated with reduced modulation of the LPP by working memory load. Results are discussed in terms of competition for attention between emotion and cognition and suggest a relationship between DLPFC activation and the allocation of attentional resources to distracting visual stimuli-a relationship that may be disrupted with increasing anxiety.

Working memory and the design of health materials: a cognitive factors perspective.

PubMed

Wilson, Elizabeth A H; Wolf, Michael S

2009-03-01

Working memory and other supportive cognitive processes involved in learning are reviewed in the context of developing patient education materials. We specifically focus on the impact of certain design factors such as text format and syntax, the inclusion of images, and the choice of modality on individuals' ability to understand and remember health information. A selective review of relevant cognitive and learning theories is discussed with regard to their potential impact on the optimal design of health materials. Working memory is measured as an individual's capacity to hold and manipulate information in active consciousness. It is limited by necessity, and well-designed health materials can effectively minimize extraneous cognitive demands placed on individuals, making working memory resources more available to better process content-related information. Further research is needed to evaluate specific design principles and identify ideal uses of print versus video-based forms of communication for conveying information. The process of developing health materials should account for the cognitive demands that extrinsic factors such as modality place on patients.

Modified stretched exponential model of computer system resources management limitations-The case of cache memory

NASA Astrophysics Data System (ADS)

Strzałka, Dominik; Dymora, Paweł; Mazurek, Mirosław

2018-02-01

In this paper we present some preliminary results in the field of computer systems management with relation to Tsallis thermostatistics and the ubiquitous problem of hardware limited resources. In the case of systems with non-deterministic behaviour, management of their resources is a key point that guarantees theirs acceptable performance and proper working. This is very wide problem that stands for many challenges in financial, transport, water and food, health, etc. areas. We focus on computer systems with attention paid to cache memory and propose to use an analytical model that is able to connect non-extensive entropy formalism, long-range dependencies, management of system resources and queuing theory. Obtained analytical results are related to the practical experiment showing interesting and valuable results.

Processing distinct linguistic information types in working memory in aphasia.

PubMed

Wright, Heather Harris; Downey, Ryan A; Gravier, Michelle; Love, Tracy; Shapiro, Lewis P

2007-06-01

BACKGROUND: Recent investigations have suggested that adults with aphasia present with a working memory deficit that may contribute to their language-processing difficulties. Working memory capacity has been conceptualised as a single "resource" pool for attentional, linguistic, and other executive processing-alternatively, it has been suggested that there may be separate working memory abilities for different types of linguistic information. A challenge in this line of research is developing an appropriate measure of working memory ability in adults with aphasia. One candidate measure of working memory ability that may be appropriate for this population is the n-back task. By manipulating stimulus type, the n-back task may be appropriate for tapping linguistic-specific working memory abilities. AIMS: The purposes of this study were (a) to measure working memory ability in adults with aphasia for processing specific types of linguistic information, and (b) to examine whether a relationship exists between participants' performance on working memory and auditory comprehension measures. METHOD #ENTITYSTARTX00026; PROCEDURES: Nine adults with aphasia participated in the study. Participants completed three n-back tasks, each tapping different types of linguistic information. They included the PhonoBack (phonological level), SemBack (semantic level), and SynBack (syntactic level). For all tasks, two n-back levels were administered: a 1-back and 2-back. Each level contained 20 target items; accuracy was recorded by stimulus presentation software. The Subject-relative, Object-relative, Active, Passive Test of Syntactic Complexity (SOAP) was the syntactic sentence comprehension task administered to all participants. OUTCOMES #ENTITYSTARTX00026; RESULTS: Participants' performance declined as n-back task difficulty increased. Overall, participants performed better on the SemBack than PhonoBack and SynBack tasks, but the differences were not statistically significant. Finally, participants who performed poorly on the SynBack also had more difficulty comprehending syntactically complex sentence structures (i.e., passive & object-relative sentences). CONCLUSIONS: Results indicate that working memory ability for different types of linguistic information can be measured in adults with aphasia. Further, our results add to the growing literature that favours separate working memory abilities for different types of linguistic information view.

Temporal dynamics of encoding, storage and reallocation of visual working memory

PubMed Central

Bays, Paul M; Gorgoraptis, Nikos; Wee, Natalie; Marshall, Louise; Husain, Masud

2012-01-01

The process of encoding a visual scene into working memory has previously been studied using binary measures of recall. Here we examine the temporal evolution of memory resolution, based on observers’ ability to reproduce the orientations of objects presented in brief, masked displays. Recall precision was accurately described by the interaction of two independent constraints: an encoding limit that determines the maximum rate at which information can be transferred into memory, and a separate storage limit that determines the maximum fidelity with which information can be maintained. Recall variability decreased incrementally with time, consistent with a parallel encoding process in which visual information from multiple objects accumulates simultaneously in working memory. No evidence was observed for a limit on the number of items stored. Cueing one display item with a brief flash led to rapid development of a recall advantage for that item. This advantage was short-lived if the cue was simply a salient visual event, but was maintained if it indicated an object of particular relevance to the task. These cueing effects were observed even for items that had already been encoded into memory, indicating that limited memory resources can be rapidly reallocated to prioritize salient or goal-relevant information. PMID:21911739

Role of auditory non-verbal working memory in sentence repetition for bilingual children with primary language impairment.

PubMed

Ebert, Kerry Danahy

2014-01-01

Sentence repetition performance is attracting increasing interest as a valuable clinical marker for primary (or specific) language impairment (LI) in both monolingual and bilingual populations. Multiple aspects of memory appear to contribute to sentence repetition performance, but non-verbal memory has not yet been considered. To explore the relationship between a measure of non-verbal auditory working memory (NVWM) and sentence repetition performance in a sample of bilingual children with LI. Forty-seven school-aged Spanish-English bilingual children with LI completed sentence repetition and non-word repetition tasks in both Spanish and English as well as an NVWM task. Hierarchical multiple linear regression was used to predict sentence repetition in each language using age, non-word repetition and NVWM. NVWM predicted unique variance in sentence repetition performance in both languages after accounting for chronological age and language-specific phonological memory, as measured by non-word repetition. Domain-general memory resources play a unique role in sentence repetition performance in children with LI. Non-verbal working memory weaknesses may contribute to the poor performance of children with LI on sentence repetition tasks. © 2014 Royal College of Speech and Language Therapists.

Temporal dynamics of encoding, storage, and reallocation of visual working memory.

PubMed

Bays, Paul M; Gorgoraptis, Nikos; Wee, Natalie; Marshall, Louise; Husain, Masud

2011-09-12

The process of encoding a visual scene into working memory has previously been studied using binary measures of recall. Here, we examine the temporal evolution of memory resolution, based on observers' ability to reproduce the orientations of objects presented in brief, masked displays. Recall precision was accurately described by the interaction of two independent constraints: an encoding limit that determines the maximum rate at which information can be transferred into memory and a separate storage limit that determines the maximum fidelity with which information can be maintained. Recall variability decreased incrementally with time, consistent with a parallel encoding process in which visual information from multiple objects accumulates simultaneously in working memory. No evidence was observed for a limit on the number of items stored. Cuing one display item with a brief flash led to rapid development of a recall advantage for that item. This advantage was short-lived if the cue was simply a salient visual event but was maintained if it indicated an object of particular relevance to the task. These cuing effects were observed even for items that had already been encoded into memory, indicating that limited memory resources can be rapidly reallocated to prioritize salient or goal-relevant information.

The Role of Auditory Nonverbal Working Memory in Sentence Repetition for Bilingual Children with Primary Language Impairment

PubMed Central

Ebert, Kerry Danahy

2015-01-01

Background Sentence repetition performance is attracting increasing interest as a valuable clinical marker for Primary (or Specific) Language Impairment (LI) in both monolingual and bilingual populations. Multiple aspects of memory appear to contribute to sentence repetition performance, but nonverbal memory has not yet been considered. Aims The purpose of this study was to explore the relationship between a measure of nonverbal auditory working memory (NVWM) and sentence repetition performance in a sample of bilingual children with LI. Methods & Procedures Forty-seven school-aged Spanish-English bilingual children with LI completed sentence repetition and nonword repetition tasks in both Spanish and English as well as an NVWM task. Hierarchical multiple linear regression was used to predict sentence repetition in each language using age, nonword repetition, and NVWM. Outcomes & Results NVWM predicted unique variance in sentence repetition performance in both languages after accounting for chronological age and language-specific phonological memory, as measured by nonword repetition. Conclusions & Implications Domain-general memory resources play a unique role in sentence repetition performance in children with LI. Nonverbal working memory weaknesses may contribute to the poor performance of children with LI on sentence repetition tasks. PMID:24894308

Distractor devaluation requires visual working memory.

PubMed

Goolsby, Brian A; Shapiro, Kimron L; Raymond, Jane E

2009-02-01

Visual stimuli seen previously as distractors in a visual search task are subsequently evaluated more negatively than those seen as targets. An attentional inhibition account for this distractor-devaluation effect posits that associative links between attentional inhibition and to-be-ignored stimuli are established during search, stored, and then later reinstantiated, implying that distractor devaluation may require visual working memory (WM) resources. To assess this, we measured distractor devaluation with and without a concurrent visual WM load. Participants viewed a memory array, performed a simple search task, evaluated one of the search items (or a novel item), and then viewed a memory test array. Although distractor devaluation was observed with low (and no) WM load, it was absent when WM load was increased. This result supports the notions that active association of current attentional states with stimuli requires WM and that memory for these associations plays a role in affective response.

Quantum Behavior of an Autonomous Maxwell Demon

NASA Astrophysics Data System (ADS)

Chapman, Adrian; Miyake, Akimasa

2015-03-01

A Maxwell Demon is an agent that can exploit knowledge of a system's microstate to perform useful work. The second law of thermodynamics is only recovered upon taking into account the work required to irreversibly update the demon's memory, bringing information theoretic concepts into a thermodynamic framework. Recently, there has been interest in modeling a classical Maxwell demon as an autonomous physical system to study this information-work tradeoff explicitly. Motivated by the idea that states with non-local entanglement structure can be used as a computational resource, we ask whether these states have thermodynamic resource quality as well by generalizing a particular classical autonomous Maxwell demon to the quantum regime. We treat the full quantum description using a matrix product operator formalism, which allows us to handle quantum and classical correlations in a unified framework. Applying this, together with techniques from statistical mechanics, we are able to approximate nonlocal quantities such as the erasure performed on the demon's memory register when correlations are present. Finally, we examine how the demon may use these correlations as a resource to outperform its classical counterpart.

ConfChem Conference on Flipped Classroom: Time-Saving Resources Aligned with Cognitive Science to Help Instructors

ERIC Educational Resources Information Center

Hartman, JudithAnn R.; Dahm, Donald J.; Nelson, Eric A.

2015-01-01

Studies in cognitive science have verified that working memory (where the brain solves problems) can manipulate nearly all elements of knowledge that can be recalled automatically from long-term memory, but only a few elements that have not previously been well memorized. Research in reading comprehension has found that "lecture notes with…

P3 amplitude attenuation secondary to increases in target-to-target interval (TTI) during spatial serial order recall: Implications for EEG models of working memory function.

PubMed

Hochberger, William C; Axelrod, Jenna L; Sarapas, Casey; Shankman, Stewart A; Hill, S Kristian

2018-06-08

Research suggests that increasing delays in stimulus read-out can trigger declines in serial order recall accuracy due to increases in cognitive demand imposed by the delay; however, the exact neural mechanisms associated with this decline are unclear. Changes in neural resource allocation present as the ideal target and can easily be monitored by examining changes in the amplitude of an ERP component known as the P3. Changes in P3 amplitude secondary to exogenous pacing of stimulus read-out via increased target-to-target intervals (TTI) during recall could reflect decreased neural resource allocation due to increased cognitive demand. This shift in resource allocation could result in working memory storage decay and the declines in serial order accuracy described by prior research. In order to examine this potential effect, participants were administered a spatial serial order processing task, with the recall series consisting of a series of correct ("match") or incorrect ("non-match" or "oddball") stimuli. Moreover, the recall series included either a brief (500ms) or extended (2000ms) delay between stimuli. Results were significant for the presence of a P3 response to non-match stimuli for both experimental conditions, and attenuation of P3 amplitude secondary to the increase in target-to-target interval (TTI). These findings suggest that extending the delay between target recognition could increase cognitive demand and trigger a decrease in neural resource allocation that results in a decay of working memory stores.

The role of attention in item-item binding in visual working memory.

PubMed

Peterson, Dwight J; Naveh-Benjamin, Moshe

2017-09-01

An important yet unresolved question regarding visual working memory (VWM) relates to whether or not binding processes within VWM require additional attentional resources compared with processing solely the individual components comprising these bindings. Previous findings indicate that binding of surface features (e.g., colored shapes) within VWM is not demanding of resources beyond what is required for single features. However, it is possible that other types of binding, such as the binding of complex, distinct items (e.g., faces and scenes), in VWM may require additional resources. In 3 experiments, we examined VWM item-item binding performance under no load, articulatory suppression, and backward counting using a modified change detection task. Binding performance declined to a greater extent than single-item performance under higher compared with lower levels of concurrent load. The findings from each of these experiments indicate that processing item-item bindings within VWM requires a greater amount of attentional resources compared with single items. These findings also highlight an important distinction between the role of attention in item-item binding within VWM and previous studies of long-term memory (LTM) where declines in single-item and binding test performance are similar under divided attention. The current findings provide novel evidence that the specific type of binding is an important determining factor regarding whether or not VWM binding processes require attention. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The irrelevant speech effect and working memory load.

PubMed

Gisselgård, Jens; Petersson, Karl Magnus; Ingvar, Martin

2004-07-01

Irrelevant speech impairs the immediate serial recall of visually presented material. Previously, we have shown that the irrelevant speech effect (ISE) was associated with a relative decrease of regional blood flow in cortical regions subserving the verbal working memory, in particular the superior temporal cortex. In this extension of the previous study, the working memory load was increased and an increased activity as a response to irrelevant speech was noted in the dorsolateral prefrontal cortex. We suggest that the two studies together provide some basic insights as to the nature of the irrelevant speech effect. Firstly, no area in the brain can be ascribed as the single locus of the irrelevant speech effect. Instead, the functional neuroanatomical substrate to the effect can be characterized in terms of changes in networks of functionally interrelated areas. Secondly, the areas that are sensitive to the irrelevant speech effect are also generically activated by the verbal working memory task itself. Finally, the impact of irrelevant speech and related brain activity depends on working memory load as indicated by the differences between the present and the previous study. From a brain perspective, the irrelevant speech effect may represent a complex phenomenon that is a composite of several underlying mechanisms, which depending on the working memory load, include top-down inhibition as well as recruitment of compensatory support and control processes. We suggest that, in the low-load condition, a selection process by an inhibitory top-down modulation is sufficient, whereas in the high-load condition, at or above working memory span, auxiliary adaptive cognitive resources are recruited as compensation. Copyright 2004 Elsevier Inc.

Running with emotion: when affective content hampers working memory performance.

PubMed

Fairfield, Beth; Mammarella, Nicola; Di Domenico, Alberto; Palumbo, Rocco

2015-03-01

This study tested the hypothesis that affective content may undermine rather than facilitate working memory (WM) performance. To this end, participants performed a running WM task with positive, negative and neutral words. In typical running memory tasks, participants are presented with lists of unpredictable length and are asked to recall the last three or four items. We found that accuracy with affective words decreased as lists lengthened, whereas list length did not influence recall of neutral words. We interpreted this pattern of results in terms of a limited resource model of WM in which valence represents additional information that needs to be manipulated, especially in the context of difficult trials. © 2014 International Union of Psychological Science.

Working memory capacity does not always support future-oriented mind-wandering.

PubMed

McVay, Jennifer C; Unsworth, Nash; McMillan, Brittany D; Kane, Michael J

2013-03-01

To evaluate the claim that mind-wandering demands executive resources, and more specifically that people with better executive control will have the resources to engage in more future-oriented thought than will those with poorer executive control, we reanalyzed thought-report data from 2 independently conducted studies (J. C. McVay & M. J. Kane, 2012, Why does working memory capacity predict variation in reading comprehension? On the influence of mind wandering and executive attention, Journal of Experimental Psychology: General, Vol. 141, pp. 302-320; N. Unsworth & B. D. McMillan, in press, Mind-wandering and reading comprehension: Examining the roles of working memory capacity, interest, motivation, and topic experience, Journal of Experimental Psychology: Learning, Memory, and Cognition) on working memory capacity (WMC), mind-wandering, and reading comprehension. Both of these individual-differences studies assessed large samples of university subjects' WMC abilities via multiple tasks and probed their immediate thought content while reading; in reporting any task-unrelated thoughts (TUTs), subjects indicated whether those thoughts were about the future or the past, if applicable. In contrast to previously published findings indicating that higher WMC subjects mind-wandered about the future more than did lower WMC subjects (B. Baird, J. Smallwood, & J. W. Schooler, 2011, Back to the future: Autobiographical planning and the functionality of mind-wandering, Consciousness and Cognition, Vol. 20, pp. 1604-1611), we found only weak to modest negative correlations between WMC and future-oriented TUTs. If anything, our findings suggest that higher WMC subjects' TUTs were somewhat less often future-oriented than were lower WMC subjects'. Either WMC is not truly associated with mind-wandering about the future, or we have identified some important boundary conditions around that association.

Individual differences in working memory capacity determine the effects of oculomotor task load on concurrent word recall performance.

PubMed

Lee, Eun-Ju; Kwon, Gusang; Lee, Aekyoung; Ghajar, Jamshid; Suh, Minah

2011-07-05

In this study, the interaction between individual differences in working memory capacity, which were assessed by the Korean version of the California Verbal Learning Test (K-CVLT), and the effects of oculomotor task load on word recall performance are examined in a dual-task experiment. We hypothesized that varying levels of oculomotor task load should result in different demands on cognitive resources. The verbal working memory task used in this study involved a brief exposure to seven words to be remembered, followed by a 30-second delay during which the subject carried out an oculomotor task. Then, memory performance was assessed by having the subjects recall as many words as possible. Forty healthy normal subjects with no vision-related problems carried out four separate dual-tasks over four consecutive days of participation, wherein word recall performances were tested under unpredictable random SPEM (smooth pursuit eye movement), predictive SPEM, fixation, and eyes-closed conditions. The word recall performance of subjects with low K-CVLT scores was significantly enhanced under predictive SPEM conditions as opposed to the fixation and eyes-closed conditions, but performance was reduced under the random SPEM condition, thus reflecting an inverted-U relationship between the oculomotor task load and word recall performance. Subjects with high K-CVLT scores evidenced steady word recall performances, regardless of the type of oculomotor task performed. The concurrent oculomotor performance measured by velocity error did not differ significantly among the K-CVLT groups. However, the high-scoring subjects evidenced smaller phase errors under predictive SPEM conditions than did the low-scoring subjects; this suggests that different resource allocation strategies may be adopted, depending on individuals' working memory capacity. Copyright © 2011 Elsevier B.V. All rights reserved.

Modality-specific alpha modulations facilitate long-term memory encoding in the presence of distracters.

PubMed

Jiang, Haiteng; van Gerven, Marcel A J; Jensen, Ole

2015-03-01

It has been proposed that long-term memory encoding is not only dependent on engaging task-relevant regions but also on disengaging task-irrelevant regions. In particular, oscillatory alpha activity has been shown to be involved in shaping the functional architecture of the working brain because it reflects the functional disengagement of specific regions in attention and memory tasks. We here ask if such allocation of resources by alpha oscillations generalizes to long-term memory encoding in a cross-modal setting in which we acquired the ongoing brain activity using magnetoencephalography. Participants were asked to encode pictures while ignoring simultaneously presented words and vice versa. We quantified the brain activity during rehearsal reflecting subsequent memory in the different attention conditions. The key finding was that successful long-term memory encoding is reflected by alpha power decreases in the sensory region of the to-be-attended modality and increases in the sensory region of the to-be-ignored modality to suppress distraction during rehearsal period. Our results corroborate related findings from attention studies by demonstrating that alpha activity is also important for the allocation of resources during long-term memory encoding in the presence of distracters.

Prefrontal Hemodynamics of Physical Activity and Environmental Complexity During Cognitive Work.

PubMed

McKendrick, Ryan; Mehta, Ranjana; Ayaz, Hasan; Scheldrup, Melissa; Parasuraman, Raja

2017-02-01

The aim of this study was to assess performance and cognitive states during cognitive work in the presence of physical work and in natural settings. Authors of previous studies have examined the interaction between cognitive and physical work, finding performance decrements in working memory. Neuroimaging has revealed increases and decreases in prefrontal oxygenated hemoglobin during the interaction of cognitive and physical work. The effect of environment on cognitive-physical dual tasking has not been previously considered. Thirteen participants were monitored with wireless functional near-infrared spectroscopy (fNIRS) as they performed an auditory 1-back task while sitting, walking indoors, and walking outdoors. Relative to sitting and walking indoors, auditory working memory performance declined when participants were walking outdoors. Sitting during the auditory 1-back task increased oxygenated hemoglobin and decreased deoxygenated hemoglobin in bilateral prefrontal cortex. Walking reduced the total hemoglobin available to bilateral prefrontal cortex. An increase in environmental complexity reduced oxygenated hemoglobin and increased deoxygenated hemoglobin in bilateral prefrontal cortex. Wireless fNIRS is capable of monitoring cognitive states in naturalistic environments. Selective attention and physical work compete with executive processing. During executive processing loading of selective attention and physical work results in deactivation of bilateral prefrontal cortex and degraded working memory performance, indicating that physical work and concomitant selective attention may supersede executive processing in the distribution of mental resources. This research informs decision-making procedures in work where working memory, physical activity, and attention interact. Where working memory is paramount, precautions should be taken to eliminate competition from physical work and selective attention.

Working memory management and predicted utility

PubMed Central

Chatham, Christopher H.; Badre, David

2013-01-01

Given the limited capacity of working memory (WM), its resources should be allocated strategically. One strategy is filtering, whereby access to WM is granted preferentially to items with the greatest utility. However, reallocation of WM resources might be required if the utility of maintained information subsequently declines. Here, we present behavioral, computational, and neuroimaging evidence that human participants track changes in the predicted utility of information in WM. First, participants demonstrated behavioral costs when the utility of items already maintained in WM declined and resources should be reallocated. An adapted Q-learning model indicated that these costs scaled with the historical utility of individual items. Finally, model-based neuroimaging demonstrated that frontal cortex tracked the utility of items to be maintained in WM, whereas ventral striatum tracked changes in the utility of items maintained in WM to the degree that these items are no longer useful. Our findings suggest that frontostriatal mechanisms track the utility of information in WM, and that these dynamics may predict delays in the removal of information from WM. PMID:23882196

Working memory maintenance is sufficient to reduce state anxiety.

PubMed

Balderston, Nicholas L; Quispe-Escudero, David; Hale, Elizabeth; Davis, Andrew; O'Connell, Katherine; Ernst, Monique; Grillon, Christian

2016-11-01

According to the attentional control theory (ACT) proposed by Eysenck and colleagues, anxiety interferes with cognitive processing by prioritizing bottom-up attentional processes over top-down attentional processes, leading to competition for access to limited resources in working memory, particularly the central executive (Eysenck, Derakshan, Santos, & Calvo, ). However, previous research using the n-back working memory task suggests that working memory load also reduces state anxiety. Assuming that similar mechanisms underlie the effect of anxiety on cognition, and the effect of cognition on anxiety, one possible implication of the ACT would suggest that the reduction of state anxiety with increasing working memory load is driven by activation of central executive attentional control processes. We tested this hypothesis using the Sternberg working memory paradigm, where maintenance processes can be isolated from central executive processes (Altamura et al., ; Sternberg, ). Consistent with the n-back results, subjects showed decreased state anxiety during the maintenance period of high-load trials relative to low-load trials, suggesting that maintenance processes alone are sufficient to achieve this state anxiety reduction. Given that the Sternberg task does not require central executive engagement, these results are not consistent with an implication of the ACT where the cognition/anxiety relationship and anxiety/cognition relationship are mediated by similar central executive mechanisms. Instead, we propose an extension of the ACT such that engaging working memory maintenance suppresses state anxiety in a load-dependent manner. Furthermore, we hypothesize that the efficacy of this effect may moderate the effect of trait anxiety on cognition. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Visuospatial bootstrapping: Binding useful visuospatial information during verbal working memory encoding does not require set-shifting executive resources.

PubMed

Calia, Clara; Darling, Stephen; Havelka, Jelena; Allen, Richard J

2018-05-01

Immediate serial recall of digits is better when the digits are shown by highlighting them in a familiar array, such as a phone keypad, compared with presenting them serially in a single location, a pattern referred to as "visuospatial bootstrapping." This pattern implies the establishment of temporary links between verbal and spatial working memory, alongside access to information in long-term memory. However, the role of working memory control processes like those implied by the "Central Executive" in bootstrapping has not been directly investigated. Here, we report a study addressing this issue, focusing on executive processes of attentional shifting. Tasks in which information has to be sequenced are thought to be heavily dependent on shifting. Memory for digits presented in keypads versus single locations was assessed under two secondary task load conditions, one with and one without a sequencing requirement, and hence differing in the degree to which they invoke shifting. Results provided clear evidence that multimodal binding (visuospatial bootstrapping) can operate independently of this form of executive control process.

Phonological and Visual Similarity Effects in Chinese and English Language Users: Implications for the Use of Cognitive Resources in Short-Term Memory

ERIC Educational Resources Information Center

Cole, Rachel L.; Pickering, Susan J.

2010-01-01

This study investigated the encoding strategies employed by Chinese and English language users when recalling sequences of pictured objects. The working memory performance of native English participants (n = 14) and Chinese speakers of English as a second language (Chinese ESL; n = 14) was compared using serial recall of visually-presented…

Memory: As It Relates to Children Ages 9 to 12 Years. Skills Essential to Learning Television Project: Working Paper.

ERIC Educational Resources Information Center

Perry, Fred L., Jr.

An overview of theory and research in memory as it relates to developmental differences is offered in this paper, which is intended to provide background information for the staff of the Skills Essential to Learning Television Project (a multi-level series of video and print resources for classroom use). A model for viewing information processing…

Relative time sharing: new findings and an extension of the resource allocation model of temporal processing.

PubMed

Buhusi, Catalin V; Meck, Warren H

2009-07-12

Individuals time as if using a stopwatch that can be stopped or reset on command. Here, we review behavioural and neurobiological data supporting the time-sharing hypothesis that perceived time depends on the attentional and memory resources allocated to the timing process. Neuroimaging studies in humans suggest that timekeeping tasks engage brain circuits typically involved in attention and working memory. Behavioural, pharmacological, lesion and electrophysiological studies in lower animals support this time-sharing hypothesis. When subjects attend to a second task, or when intruder events are presented, estimated durations are shorter, presumably due to resources being taken away from timing. Here, we extend the time-sharing hypothesis by proposing that resource reallocation is proportional to the perceived contrast, both in temporal and non-temporal features, between intruders and the timed events. New findings support this extension by showing that the effect of an intruder event is dependent on the relative duration of the intruder to the intertrial interval. The conclusion is that the brain circuits engaged by timekeeping comprise not only those primarily involved in time accumulation, but also those involved in the maintenance of attentional and memory resources for timing, and in the monitoring and reallocation of those resources among tasks.

An interference model of visual working memory.

PubMed

Oberauer, Klaus; Lin, Hsuan-Yu

2017-01-01

The article introduces an interference model of working memory for information in a continuous similarity space, such as the features of visual objects. The model incorporates the following assumptions: (a) Probability of retrieval is determined by the relative activation of each retrieval candidate at the time of retrieval; (b) activation comes from 3 sources in memory: cue-based retrieval using context cues, context-independent memory for relevant contents, and noise; (c) 1 memory object and its context can be held in the focus of attention, where it is represented with higher precision, and partly shielded against interference. The model was fit to data from 4 continuous-reproduction experiments testing working memory for colors or orientations. The experiments involved variations of set size, kind of context cues, precueing, and retro-cueing of the to-be-tested item. The interference model fit the data better than 2 competing models, the Slot-Averaging model and the Variable-Precision resource model. The interference model also fared well in comparison to several new models incorporating alternative theoretical assumptions. The experiments confirm 3 novel predictions of the interference model: (a) Nontargets intrude in recall to the extent that they are close to the target in context space; (b) similarity between target and nontarget features improves recall, and (c) precueing-but not retro-cueing-the target substantially reduces the set-size effect. The success of the interference model shows that working memory for continuous visual information works according to the same principles as working memory for more discrete (e.g., verbal) contents. Data and model codes are available at https://osf.io/wgqd5/. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

The effect of functional hearing loss and age on long- and short-term visuospatial memory: evidence from the UK biobank resource.

PubMed

Rönnberg, Jerker; Hygge, Staffan; Keidser, Gitte; Rudner, Mary

2014-01-01

The UK Biobank offers cross-sectional epidemiological data collected on >500,000 individuals in the UK between 40 and 70 years of age. Using the UK Biobank data, the aim of this study was to investigate the effects of functional hearing loss and hearing aid usage on visuospatial memory function. This selection of variables resulted in a sub-sample of 138,098 participants after discarding extreme values. A digit triplets functional hearing test was used to divide the participants into three groups: poor, insufficient and normal hearers. We found negative relationships between functional hearing loss and both visuospatial working memory (i.e., a card pair matching task) and visuospatial, episodic long-term memory (i.e., a prospective memory task), with the strongest association for episodic long-term memory. The use of hearing aids showed a small positive effect for working memory performance for the poor hearers, but did not have any influence on episodic long-term memory. Age also showed strong main effects for both memory tasks and interacted with gender and education for the long-term memory task. Broader theoretical implications based on a memory systems approach will be discussed and compared to theoretical alternatives.

Cognitive and neuropsychological underpinnings of relational and conjunctive working memory binding across age.

PubMed

van Geldorp, Bonnie; Parra, Mario A; Kessels, Roy P C

2015-01-01

The ability to form associations (i.e., binding) is critical for memory formation. Recent studies suggest that aging specifically affects relational binding (associating separate features) but not conjunctive binding (integrating features within an object). Possibly, this dissociation may be driven by the spatial nature of the studies so far. Alternatively, relational binding may simply require more attentional resources. We assessed relational and conjunctive binding in three age groups and we included an interfering task (i.e., an articulatory suppression task). Binding was examined in a working memory (WM) task using non-spatial features: shape and colour. Thirty-one young adults (mean age = 22.35), 30 middle-aged adults (mean age = 54.80) and 30 older adults (mean age = 70.27) performed the task. Results show an effect of type of binding and an effect of age but no interaction between type of binding and age. The interaction between type of binding and interference was significant. These results indicate that aging affects relational binding and conjunctive binding similarly. However, relational binding is more susceptible to interference than conjunctive binding, which suggests that relational binding may require more attentional resources. We suggest that a general decline in WM resources associated with frontal dysfunction underlies age-related deficits in WM binding.

Effects of reverberation time on the cognitive load in speech communication: theoretical considerations.

PubMed

Kjellberg, A

2004-01-01

The paper presents a theoretical analysis of possible effects of reverberation time on the cognitive load in speech communication. Speech comprehension requires not only phonological processing of the spoken words. Simultaneously, this information must be further processed and stored. All this processing takes place in the working memory, which has a limited processing capacity. The more resources that are allocated to word identification, the fewer resources are therefore left for the further processing and storing of the information. Reverberation conditions that allow the identification of almost all words may therefore still interfere with speech comprehension and memory storing. These problems are likely to be especially serious in situations where speech has to be followed continuously for a long time. An unfavourable reverberation time (RT) then could contribute to the development of cognitive fatigue, which means that working memory resources are gradually reduced. RT may also affect the cognitive load in two other ways: RT may change the distracting effects of a sound and a person's mood. Both effects could influence the cognitive load of a listener. It is argued that we need studies of RT effects in realistic long-lasting listening situations to better understand the effect of RT on speech communication. Furthermore, the effect of RT on distraction and mood need to be better understood.

Anterior medial prefrontal cortex exhibits activation during task preparation but deactivation during task execution.

PubMed

Koshino, Hideya; Minamoto, Takehiro; Ikeda, Takashi; Osaka, Mariko; Otsuka, Yuki; Osaka, Naoyuki

2011-01-01

The anterior prefrontal cortex (PFC) exhibits activation during some cognitive tasks, including episodic memory, reasoning, attention, multitasking, task sets, decision making, mentalizing, and processing of self-referenced information. However, the medial part of anterior PFC is part of the default mode network (DMN), which shows deactivation during various goal-directed cognitive tasks compared to a resting baseline. One possible factor for this pattern is that activity in the anterior medial PFC (MPFC) is affected by dynamic allocation of attentional resources depending on task demands. We investigated this possibility using an event related fMRI with a face working memory task. Sixteen students participated in a single fMRI session. They were asked to form a task set to remember the faces (Face memory condition) or to ignore them (No face memory condition), then they were given 6 seconds of preparation period before the onset of the face stimuli. During this 6-second period, four single digits were presented one at a time at the center of the display, and participants were asked to add them and to remember the final answer. When participants formed a task set to remember faces, the anterior MPFC exhibited activation during a task preparation period but deactivation during a task execution period within a single trial. The results suggest that the anterior MPFC plays a role in task set formation but is not involved in execution of the face working memory task. Therefore, when attentional resources are allocated to other brain regions during task execution, the anterior MPFC shows deactivation. The results suggest that activation and deactivation in the anterior MPFC are affected by dynamic allocation of processing resources across different phases of processing.

Anterior Medial Prefrontal Cortex Exhibits Activation during Task Preparation but Deactivation during Task Execution

PubMed Central

Koshino, Hideya; Minamoto, Takehiro; Ikeda, Takashi; Osaka, Mariko; Otsuka, Yuki; Osaka, Naoyuki

2011-01-01

Background The anterior prefrontal cortex (PFC) exhibits activation during some cognitive tasks, including episodic memory, reasoning, attention, multitasking, task sets, decision making, mentalizing, and processing of self-referenced information. However, the medial part of anterior PFC is part of the default mode network (DMN), which shows deactivation during various goal-directed cognitive tasks compared to a resting baseline. One possible factor for this pattern is that activity in the anterior medial PFC (MPFC) is affected by dynamic allocation of attentional resources depending on task demands. We investigated this possibility using an event related fMRI with a face working memory task. Methodology/Principal Findings Sixteen students participated in a single fMRI session. They were asked to form a task set to remember the faces (Face memory condition) or to ignore them (No face memory condition), then they were given 6 seconds of preparation period before the onset of the face stimuli. During this 6-second period, four single digits were presented one at a time at the center of the display, and participants were asked to add them and to remember the final answer. When participants formed a task set to remember faces, the anterior MPFC exhibited activation during a task preparation period but deactivation during a task execution period within a single trial. Conclusions/Significance The results suggest that the anterior MPFC plays a role in task set formation but is not involved in execution of the face working memory task. Therefore, when attentional resources are allocated to other brain regions during task execution, the anterior MPFC shows deactivation. The results suggest that activation and deactivation in the anterior MPFC are affected by dynamic allocation of processing resources across different phases of processing. PMID:21829668

Mental Objects in Working Memory: Development of Basic Capacity or of Cognitive Completion?

PubMed Central

Cowan, Nelson

2018-01-01

Working memory is the small amount of information that we hold in mind and use to carry out cognitive processes such as language comprehension and production, problem-solving, and decision-making. In order to understand cognitive development, it would be helpful to know whether working memory increases in capacity with development and, if so, how and why. I will focus on two major stumbling blocks toward understanding working memory development, namely that (1) many potentially relevant aspects of the mind change in parallel during development, obscuring the role of any one change; and (2) one cannot use the same test procedure from infancy to adulthood, complicating comparisons across age groups. With regard to the first stumbling block, the parallel development of different aspects of the mind, we discuss research in which attempts were made to hold constant some factors (knowledge, strategies, direction of attention) to investigate whether developmental differences remain. With regard to the second stumbling block, procedural differences in tests at different age groups, I suggest ways in which the results might be reconciled across procedures. I highlight the value of pursuing research that could distinguish between two different key hypotheses that emerge: that there is a developmental increase in the number of working memory slots (or in a basic resource that holds items in working memory), and that there is a developmental increase in the amount of detail that each of these slots can hold. PMID:28215289

Mental Objects in Working Memory: Development of Basic Capacity or of Cognitive Completion?

PubMed

Cowan, N

2017-01-01

Working memory is the small amount of information that we hold in mind and use to carry out cognitive processes such as language comprehension and production, problem solving, and decision making. In order to understand cognitive development, it would be helpful to know whether working memory increases in capacity with development and, if so, how and why. I will focus on two major stumbling blocks toward understanding working memory development, namely that (1) many potentially relevant aspects of the mind change in parallel during development, obscuring the role of any one change; and (2) one cannot use the same test procedure from infancy to adulthood, complicating comparisons across age groups. With regard to the first stumbling block, the parallel development of different aspects of the mind, we discuss research in which attempts were made to hold constant some factors (knowledge, strategies, direction of attention) to investigate whether developmental differences remain. With regard to the second stumbling block, procedural differences in tests for different age groups, I suggest ways in which the results might be reconciled across procedures. I highlight the value of pursuing research that could distinguish between two different key hypotheses that emerge: that there is a developmental increase in the number of working memory slots (or in a basic resource that holds items in working memory), and that there is a developmental increase in the amount of detail that each of these slots can hold. © 2017 Elsevier Inc. All rights reserved.

The Effects of Stress on Reading: A Comparison of First-Language versus Intermediate Second-Language Reading Comprehension

ERIC Educational Resources Information Center

Rai, Manpreet K.; Loschky, Lester C.; Harris, Richard Jackson

2015-01-01

This study investigated how resource-demanding reading tasks and stressful conditions affect 1st-language (L1) and intermediate 2nd-language (L2) reading comprehension. Using the attentional control theory framework (Eysenck, Derakshan, Santos, & Calvo, 2007), we investigated the roles of central executive working memory (WM) resources,…

The Contribution of Verbal Working Memory to Deaf Children’s Oral and Written Production

PubMed Central

Arfé, Barbara; Rossi, Cristina; Sicoli, Silvia

2015-01-01

This study investigated the contribution of verbal working memory to the oral and written story production of deaf children. Participants were 29 severely to profoundly deaf children aged 8–13 years and 29 hearing controls, matched for grade level. The children narrated a picture story orally and in writing and performed a reading comprehension test, the Wechsler Intelligence Scale for Children-Fourth Edition forward digit span task, and a reading span task. Oral and written stories were analyzed at the microstructural (i.e., clause) and macrostructural (discourse) levels. Hearing children’s stories scored higher than deaf children’s at both levels. Verbal working memory skills contributed to deaf children’s oral and written production over and above age and reading comprehension skills. Verbal rehearsal skills (forward digit span) contributed significantly to deaf children’s ability to organize oral and written stories at the microstructural level; they also accounted for unique variance at the macrostructural level in writing. Written story production appeared to involve greater verbal working memory resources than oral story production. PMID:25802319

A Stream Tilling Approach to Surface Area Estimation for Large Scale Spatial Data in a Shared Memory System

NASA Astrophysics Data System (ADS)

Liu, Jiping; Kang, Xiaochen; Dong, Chun; Xu, Shenghua

2017-12-01

Surface area estimation is a widely used tool for resource evaluation in the physical world. When processing large scale spatial data, the input/output (I/O) can easily become the bottleneck in parallelizing the algorithm due to the limited physical memory resources and the very slow disk transfer rate. In this paper, we proposed a stream tilling approach to surface area estimation that first decomposed a spatial data set into tiles with topological expansions. With these tiles, the one-to-one mapping relationship between the input and the computing process was broken. Then, we realized a streaming framework towards the scheduling of the I/O processes and computing units. Herein, each computing unit encapsulated a same copy of the estimation algorithm, and multiple asynchronous computing units could work individually in parallel. Finally, the performed experiment demonstrated that our stream tilling estimation can efficiently alleviate the heavy pressures from the I/O-bound work, and the measured speedup after being optimized have greatly outperformed the directly parallel versions in shared memory systems with multi-core processors.

Visual Working Memory Capacity: From Psychophysics and Neurobiology to Individual Differences

PubMed Central

Luck, Steven J.; Vogel, Edward K.

2013-01-01

Visual working memory capacity is of great interest because it is strongly correlated with overall cognitive ability, can be understood at the level of neural circuits, and is easily measured. Recent studies have shown that capacity influences tasks ranging from saccade targeting to analogical reasoning. A debate has arisen over whether capacity is constrained by a limited number of discrete representations or by an infinitely divisible resource, but the empirical evidence and neural network models currently favor a discrete item limit. Capacity differs markedly across individuals and groups, and recent research indicates that some of these differences reflect true differences in storage capacity whereas others reflect variations in the ability to use memory capacity efficiently. PMID:23850263

How do we learn to "kill" in volleyball?: The role of working memory capacity and expertise in volleyball motor learning.

PubMed

Bisagno, Elisa; Morra, Sergio

2018-03-01

This study examines young volleyball players' learning of increasingly complex attack gestures. The main purpose of the study was to examine the predictive role of a cognitive variable, working memory capacity (or "M capacity"), in the acquisition and development of motor skills in a structured sport. Pascual-Leone's theory of constructive operators (TCO) was used as a framework; it defines working memory capacity as the maximum number of schemes that can be simultaneously activated by attentional resources. The role of expertise in motor learning was also considered. The expertise of each athlete was assessed in terms of years of practice and number of training sessions per week. The participants were 120 volleyball players, aged between 6 and 26 years, who performed both working memory tests and practical tests of volleyball involving the execution of the "third touch" by means of technical gestures of varying difficulty. We proposed a task analysis of these different gestures framed within the TCO. The results pointed to a very clear dissociation. On the one hand, M capacity was the best predictor of correct motor performance, and a specific capacity threshold was found for learning each attack gesture. On the other hand, experience was the key for the precision of the athletic gestures. This evidence could underline the existence of two different cognitive mechanisms in motor learning. The first one, relying on attentional resources, is required to learn a gesture. The second one, based on repeated experience, leads to its automatization. Copyright © 2017 Elsevier Inc. All rights reserved.

Attentional and non-attentional systems in the maintenance of verbal information in working memory: the executive and phonological loops

PubMed Central

Camos, Valérie; Barrouillet, Pierre

2014-01-01

Working memory is the structure devoted to the maintenance of information at short term during concurrent processing activities. In this respect, the question regarding the nature of the mechanisms and systems fulfilling this maintenance function is of particular importance and has received various responses in the recent past. In the time-based resource-sharing (TBRS) model, we suggest that only two systems sustain the maintenance of information at the short term, counteracting the deleterious effect of temporal decay and interference. A non-attentional mechanism of verbal rehearsal, similar to the one described by Baddeley in the phonological loop model, uses language processes to reactivate phonological memory traces. Besides this domain-specific mechanism, an executive loop allows the reconstruction of memory traces through an attention-based mechanism of refreshing. The present paper reviews evidence of the involvement of these two independent systems in the maintenance of verbal memory items. PMID:25426049

Visual Short-Term Memory Compared in Rhesus Monkeys and Humans

PubMed Central

Elmore, L. Caitlin; Ma, Wei Ji; Magnotti, John F.; Leising, Kenneth J.; Passaro, Antony D.; Katz, Jeffrey S.; Wright, Anthony A.

2011-01-01

Summary Change detection is a popular task to study visual short-term memory (STM) in humans [1–4]. Much of this work suggests that STM has a fixed capacity of 4 ± 1 items [1–6]. Here we report the first comparison of change detection memory between humans and a species closely related to humans, the rhesus monkey. Monkeys and humans were tested in nearly identical procedures with overlapping display sizes. Although the monkeys’ STM was well fit by a 1-item fixed-capacity memory model, other monkey memory tests with 4-item lists have shown performance impossible to obtain with a 1-item capacity [7]. We suggest that this contradiction can be resolved using a continuous-resource approach more closely tied to the neural basis of memory [8,9]. In this view, items have a noisy memory representation whose noise level depends on display size due to distributed allocation of a continuous resource. In accord with this theory, we show that performance depends on the perceptual distance between items before and after the change, and d′ depends on display size in an approximately power law fashion. Our results open the door to combining the power of psychophysics, computation, and physiology to better understand the neural basis of STM. PMID:21596568

Stressing the mind: the effect of cognitive load and articulatory suppression on attentional guidance from working memory.

PubMed

Soto, David; Humphreys, Glyn W

2008-07-01

Four experiments explored the effect of cognitive load on the time course of top-down guidance of attention from working memory (WM). Observers had to search for a target presented among several distractors, with the target and distractor stimuli embedded inside different objects. On half of the trials, one of the distractor objects was cued by a matching item held in WM. When a single item was maintained in memory, search performance was impaired relative to a neutral baseline, where the memory and search displays did not match. These effects of WM on subsequent search were reduced by including a verbal suppression task during the WM and search displays, and by varying the WM load. The degree of competition for resources in WM is a key factor in determining the time course and magnitude of the interaction between WM and visual selection.

Computer Game Play Reduces Intrusive Memories of Experimental Trauma via Reconsolidation-Update Mechanisms.

PubMed

James, Ella L; Bonsall, Michael B; Hoppitt, Laura; Tunbridge, Elizabeth M; Geddes, John R; Milton, Amy L; Holmes, Emily A

2015-08-01

Memory of a traumatic event becomes consolidated within hours. Intrusive memories can then flash back repeatedly into the mind's eye and cause distress. We investigated whether reconsolidation-the process during which memories become malleable when recalled-can be blocked using a cognitive task and whether such an approach can reduce these unbidden intrusions. We predicted that reconsolidation of a reactivated visual memory of experimental trauma could be disrupted by engaging in a visuospatial task that would compete for visual working memory resources. We showed that intrusive memories were virtually abolished by playing the computer game Tetris following a memory-reactivation task 24 hr after initial exposure to experimental trauma. Furthermore, both memory reactivation and playing Tetris were required to reduce subsequent intrusions (Experiment 2), consistent with reconsolidation-update mechanisms. A simple, noninvasive cognitive-task procedure administered after emotional memory has already consolidated (i.e., > 24 hours after exposure to experimental trauma) may prevent the recurrence of intrusive memories of those emotional events. © The Author(s) 2015.

Computer Game Play Reduces Intrusive Memories of Experimental Trauma via Reconsolidation-Update Mechanisms

PubMed Central

James, Ella L.; Bonsall, Michael B.; Hoppitt, Laura; Tunbridge, Elizabeth M.; Geddes, John R.; Milton, Amy L.

2015-01-01

Memory of a traumatic event becomes consolidated within hours. Intrusive memories can then flash back repeatedly into the mind’s eye and cause distress. We investigated whether reconsolidation—the process during which memories become malleable when recalled—can be blocked using a cognitive task and whether such an approach can reduce these unbidden intrusions. We predicted that reconsolidation of a reactivated visual memory of experimental trauma could be disrupted by engaging in a visuospatial task that would compete for visual working memory resources. We showed that intrusive memories were virtually abolished by playing the computer game Tetris following a memory-reactivation task 24 hr after initial exposure to experimental trauma. Furthermore, both memory reactivation and playing Tetris were required to reduce subsequent intrusions (Experiment 2), consistent with reconsolidation-update mechanisms. A simple, noninvasive cognitive-task procedure administered after emotional memory has already consolidated (i.e., > 24 hours after exposure to experimental trauma) may prevent the recurrence of intrusive memories of those emotional events. PMID:26133572

Cognitive-behavioral and electrophysiological evidence of the affective consequences of ignoring stimulus representations in working memory.

PubMed

De Vito, David; Ferrey, Anne E; Fenske, Mark J; Al-Aidroos, Naseem

2018-06-01

Ignoring visual stimuli in the external environment leads to decreased liking of those items, a phenomenon attributed to the affective consequences of attentional inhibition. Here we investigated the generality of this "distractor devaluation" phenomenon by asking whether ignoring stimuli represented internally within visual working memory has the same affective consequences. In two experiments we presented participants with two or three visual stimuli and then, after the stimuli were no longer visible, provided an attentional cue indicating which item in memory was the target they would have to later recall, and which were task-irrelevant distractors. Participants subsequently judged how much they liked these stimuli. Previously-ignored distractors were consistently rated less favorably than targets, replicating prior findings of distractor devaluation. To gain converging evidence, in Experiment 2, we also examined the electrophysiological processes associated with devaluation by measuring individual differences in attention (N2pc) and working memory (CDA) event-related potentials following the attention cue. Larger amplitude of an N2pc-like component was associated with greater devaluation, suggesting that individuals displaying more effective selection of memory targets-an act aided by distractor inhibition-displayed greater levels of distractor devaluation. Individuals showing a larger post-cue CDA amplitude (but not pre-cue CDA amplitude) also showed greater distractor devaluation, supporting prior evidence that visual working-memory resources have a functional role in effecting devaluation. Together, these findings demonstrate that ignoring working-memory representations has affective consequences, and adds to the growing evidence that the contribution of selective-attention mechanisms to a wide range of human thoughts and behaviors leads to devaluation.

Physicians' perceptions of capacity building for managing chronic disease in seniors using integrated interprofessional care models.

PubMed

Lee, Linda; Heckman, George; McKelvie, Robert; Jong, Philip; D'Elia, Teresa; Hillier, Loretta M

2015-03-01

To explore the barriers to and facilitators of adapting and expanding a primary care memory clinic model to integrate care of additional complex chronic geriatric conditions (heart failure, falls, chronic obstructive pulmonary disease, and frailty) into care processes with the goal of improving outcomes for seniors. Mixed-methods study using quantitative (questionnaires) and qualitative (interviews) methods. Ontario. Family physicians currently working in primary care memory clinic teams and supporting geriatric specialists. Family physicians currently working in memory clinic teams (n = 29) and supporting geriatric specialists(n = 9) were recruited as survey participants. Interviews were conducted with memory clinic lead physicians (n = 16).Statistical analysis was done to assess differences between family physician ratings and geriatric specialist ratings related to the capacity for managing complex chronic geriatric conditions, the role of interprofessional collaboration within primary care, and funding and staffing to support geriatric care. Results from both study methods were compared to identify common findings. Results indicate overall support for expanding the memory clinic model to integrate care for other complex conditions. However, the current primary care structure is challenged to support optimal management of patients with multiple comorbidities, particularly as related to limited funding and staffing resources. Structured training, interprofessional teams, and an active role of geriatric specialists within primary care were identified as important facilitators. The memory clinic model, as applied to other complex chronic geriatric conditions, has the potential to build capacity for high-quality primary care, improve health outcomes,promote efficient use of health care resources, and reduce healthcare costs.

Blood Alcohol Concentration-Related Lower Performance in Immediate Visual Memory and Working Memory in Adolescent Binge Drinkers

PubMed Central

Vinader-Caerols, Concepción; Duque, Aránzazu; Montañés, Adriana; Monleón, Santiago

2017-01-01

The binge drinking (BD) pattern of alcohol consumption is prevalent during adolescence, a period characterized by critical changes to the structural and functional development of brain areas related with memory and cognition. There is considerable evidence of the cognitive dysfunctions caused by the neurotoxic effects of BD in the not-yet-adult brain. Thus, the aim of the present study was to evaluate the effects of different blood alcohol concentrations (BAC) on memory during late adolescence (18–19 years old) in males and females with a history of BD. The sample consisted of 154 adolescents (67 males and 87 females) that were classified as refrainers if they had never previously drunk alcoholic drinks and as binge drinkers if they had drunk six or more standard drink units in a row for men or five or more for women at a minimum frequency of three occasions in a month, throughout the previous 12 months. After intake of a high acute dose of alcohol by binge drinkers or a control refreshment by refrainers and binge drinkers, subjects were distributed into four groups for each gender according to their BAC: BAC0-R (0 g/L, in refrainers), BAC0-BD (0 g/L, in binge drinkers), BAC1 (0.3 – 0.5 g/L, in binge drinkers) or BAC2 (0.54 – 1.1 g/L, in binge drinkers). The subjects’ immediate visual memory and working memory were then measured according to the Wechsler Memory Scale (WMS-III). The BAC1 group showed lower scores of immediate visual memory but not of working memory, while lower performance in both memories were found in the BAC2 group. Therefore, the brain of binge drinkers with moderate BAC could be employing compensatory mechanisms from additional brain areas to perform a working memory task adequately, but these resources would be undermined when BAC is higher (>0.5 g/L). No gender differences were found in BAC-related lower performance in immediate visual memory and working memory. In conclusion, immediate visual memory is more sensitive than working memory to the neurotoxic effects of alcohol in adolescent binge drinkers of both genders, being a BAC-related lower performance, and without obvious differences between males and females. PMID:29046656

Blood Alcohol Concentration-Related Lower Performance in Immediate Visual Memory and Working Memory in Adolescent Binge Drinkers.

PubMed

Vinader-Caerols, Concepción; Duque, Aránzazu; Montañés, Adriana; Monleón, Santiago

2017-01-01

The binge drinking (BD) pattern of alcohol consumption is prevalent during adolescence, a period characterized by critical changes to the structural and functional development of brain areas related with memory and cognition. There is considerable evidence of the cognitive dysfunctions caused by the neurotoxic effects of BD in the not-yet-adult brain. Thus, the aim of the present study was to evaluate the effects of different blood alcohol concentrations (BAC) on memory during late adolescence (18-19 years old) in males and females with a history of BD. The sample consisted of 154 adolescents (67 males and 87 females) that were classified as refrainers if they had never previously drunk alcoholic drinks and as binge drinkers if they had drunk six or more standard drink units in a row for men or five or more for women at a minimum frequency of three occasions in a month, throughout the previous 12 months. After intake of a high acute dose of alcohol by binge drinkers or a control refreshment by refrainers and binge drinkers, subjects were distributed into four groups for each gender according to their BAC: BAC0-R (0 g/L, in refrainers), BAC0-BD (0 g/L, in binge drinkers), BAC1 (0.3 - 0.5 g/L, in binge drinkers) or BAC2 (0.54 - 1.1 g/L, in binge drinkers). The subjects' immediate visual memory and working memory were then measured according to the Wechsler Memory Scale (WMS-III). The BAC1 group showed lower scores of immediate visual memory but not of working memory, while lower performance in both memories were found in the BAC2 group. Therefore, the brain of binge drinkers with moderate BAC could be employing compensatory mechanisms from additional brain areas to perform a working memory task adequately, but these resources would be undermined when BAC is higher (>0.5 g/L). No gender differences were found in BAC-related lower performance in immediate visual memory and working memory. In conclusion, immediate visual memory is more sensitive than working memory to the neurotoxic effects of alcohol in adolescent binge drinkers of both genders, being a BAC-related lower performance, and without obvious differences between males and females.

Your brain on speed: cognitive performance of a spatial working memory task is not affected by walking speed

PubMed Central

Kline, Julia E.; Poggensee, Katherine; Ferris, Daniel P.

2014-01-01

When humans walk in everyday life, they typically perform a range of cognitive tasks while they are on the move. Past studies examining performance changes in dual cognitive-motor tasks during walking have produced a variety of results. These discrepancies may be related to the type of cognitive task chosen, differences in the walking speeds studied, or lack of controlling for walking speed. The goal of this study was to determine how young, healthy subjects performed a spatial working memory task over a range of walking speeds. We used high-density electroencephalography to determine if electrocortical activity mirrored changes in cognitive performance across speeds. Subjects stood (0.0 m/s) and walked (0.4, 0.8, 1.2, and 1.6 m/s) with and without performing a Brooks spatial working memory task. We hypothesized that performance of the spatial working memory task and the associated electrocortical activity would decrease significantly with walking speed. Across speeds, the spatial working memory task caused subjects to step more widely compared with walking without the task. This is typically a sign that humans are adapting their gait dynamics to increase gait stability. Several cortical areas exhibited power fluctuations time-locked to memory encoding during the cognitive task. In the somatosensory association cortex, alpha power increased prior to stimulus presentation and decreased during memory encoding. There were small significant reductions in theta power in the right superior parietal lobule and the posterior cingulate cortex around memory encoding. However, the subjects did not show a significant change in cognitive task performance or electrocortical activity with walking speed. These findings indicate that in young, healthy subjects walking speed does not affect performance of a spatial working memory task. These subjects can devote adequate cortical resources to spatial cognition when needed, regardless of walking speed. PMID:24847239

Interaction of threat and verbal working memory in adolescents.

PubMed

Patel, Nilam; Vytal, Katherine; Pavletic, Nevia; Stoodley, Catherine; Pine, Daniel S; Grillon, Christian; Ernst, Monique

2016-04-01

Threat induces a state of sustained anxiety that can disrupt cognitive processing, and, reciprocally, cognitive processing can modulate an anxiety response to threat. These effects depend on the level of cognitive engagement, which itself varies as a function of task difficulty. In adults, we recently showed that induced anxiety impaired working memory accuracy at low and medium but not high load. Conversely, increasing the task load reduced the physiological correlates of anxiety (anxiety-potentiated startle). The present work examines such threat-cognition interactions as a function of age. We expected threat to more strongly impact working memory in younger individuals by virtue of putatively restricted cognitive resources and weaker emotion regulation. This was tested by examining the influence of age on the interaction of anxiety and working memory in 25 adolescents (10 to 17 years) and 25 adults (22 to 46 years). Working memory load was manipulated using a verbal n-back task. Anxiety was induced using the threat of an aversive loud scream and measured via eyeblink startle. Findings revealed that, in both age groups, accuracy was lower during threat than safe conditions at low and medium but not high load, and reaction times were faster during threat than safe conditions at high load but did not differ at other loads. Additionally, anxiety-potentiated startle was greater during low and medium than high load. Thus, the interactions of anxiety with working memory appear similar in adolescents and adults. Whether these similarities reflect common neural mechanisms would need to be assessed using functional neuroimaging. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

The Meeting Point: Where Language Production and Working Memory Share Resources.

PubMed

Ishkhanyan, Byurakn; Boye, Kasper; Mogensen, Jesper

2018-06-07

The interaction between working memory and language processing is widely discussed in cognitive research. However, those studies often explore the relationship between language comprehension and working memory (WM). The role of WM is rarely considered in language production, despite some evidence suggesting a relationship between the two cognitive systems. This study attempts to fill that gap by using a complex span task during language production. We make our predictions based on the reorganization of elementary functions neurocognitive model, a usage based theory about grammatical status, and language production models. In accordance with these theories, we expect an overlap between language production and WM at one or more levels of language planning. Our results show that WM is involved at the phonological encoding level of language production and that adding WM load facilitates language production, which leads us to suggest that an extra task-specific storage is being created while the task is performed.

Configural Representations in Spatial Working Memory: Modulation by Perceptual Segregation and Voluntary Attention

PubMed Central

Gmeindl, Leon; Nelson, James K.; Wiggin, Timothy; Reuter-Lorenz, Patricia A.

2011-01-01

In what form are multiple spatial locations represented in working memory? The current study revealed that people often maintain the configural properties (inter-item relationships) of visuospatial stimuli even when this information is explicitly task-irrelevant. However, results also indicate that the voluntary allocation of selective attention prior to stimulus presentation, as well as feature-based perceptual segregation of relevant from irrelevant stimuli, can eliminate the influences of stimulus configuration on location change detection performance. In contrast, voluntary attention cued to the relevant target location following presentation of the stimulus array failed to attenuate these influences. Thus, whereas voluntary selective attention can isolate or prevent the encoding of irrelevant stimulus locations and configural properties, people, perhaps due to limitations in attentional resources, reliably fail to isolate or suppress configural representations that have been encoded into working memory. PMID:21761373

Executive control processes underlying multi-item working memory

PubMed Central

Lara, Antonio H.; Wallis, Jonathan D.

2014-01-01

A dominant view of prefrontal cortex (PFC) function is that it stores task-relevant information in working memory. To examine this and determine how it applies when multiple pieces of information must be stored, we trained two macaque monkeys to perform a multi-item color change-detection task and recorded activity of neurons in PFC. Few neurons encoded the color of the items. Instead, the predominant encoding was spatial: a static signal reflecting the item's position and a dynamic signal reflecting the animal's covert attention. These findings challenge the notion that PFC stores task-relevant information. Instead, we suggest that the contribution of PFC is in controlling the allocation of resources to support working memory. In support of this, we found that increased power in the alpha and theta bands of PFC local field potentials, which are thought to reflect long-range communication with other brain areas, was correlated with more precise color representations. PMID:24747574

Effects of Age, Acoustic Challenge, and Verbal Working Memory on Recall of Narrative Speech.

PubMed

Ward, Caitlin M; Rogers, Chad S; Van Engen, Kristin J; Peelle, Jonathan E

2016-01-01

A common goal during speech comprehension is to remember what we have heard. Encoding speech into long-term memory frequently requires processes such as verbal working memory that may also be involved in processing degraded speech. Here the authors tested whether young and older adult listeners' memory for short stories was worse when the stories were acoustically degraded, or whether the additional contextual support provided by a narrative would protect against these effects. The authors tested 30 young adults (aged 18-28 years) and 30 older adults (aged 65-79 years) with good self-reported hearing. Participants heard short stories that were presented as normal (unprocessed) speech or acoustically degraded using a noise vocoding algorithm with 24 or 16 channels. The degraded stories were still fully intelligible. Following each story, participants were asked to repeat the story in as much detail as possible. Recall was scored using a modified idea unit scoring approach, which included separately scoring hierarchical levels of narrative detail. Memory for acoustically degraded stories was significantly worse than for normal stories at some levels of narrative detail. Older adults' memory for the stories was significantly worse overall, but there was no interaction between age and acoustic clarity or level of narrative detail. Verbal working memory (assessed by reading span) significantly correlated with recall accuracy for both young and older adults, whereas hearing ability (better ear pure tone average) did not. The present findings are consistent with a framework in which the additional cognitive demands caused by a degraded acoustic signal use resources that would otherwise be available for memory encoding for both young and older adults. Verbal working memory is a likely candidate for supporting both of these processes.

Efficient Parallel Algorithms on Restartable Fail-Stop Processors

DTIC Science & Technology

1991-01-01

resource (memory), and ( 3 ) that processors, memory and their interconnection must be The model of parallel computation known as the Par- perfectly...setting), arid ure an(I restart errors. We describe these arguments if] [AAtPS 871 (in a deterministic setting). Fault-tolerance Section 3 . of...grannmarity at the processor level --- for recent work on where Al is the nmber of failures during this step’s gate granilarities see [All 90, Pip 85

Studies of Implicit Prototype Extraction In Patients with Mild Cognitive Impairment and Early Alzheimer’s Disease

PubMed Central

Nosofsky, Robert M.; Denton, Stephen E.; Zaki, Safa R.; Murphy-Knudsen, Anne F.; Unverzagt, Frederick W.

2013-01-01

Studies of incidental category learning support the hypothesis of an implicit prototype-extraction system which is distinct from explicit memory (Smith, 2008). In those studies, patients with explicit-memory impairments due to damage to the medial-temporal lobe performed normally in implicit categorization tasks (Bozoki, Grossman, & Smith, 2006; Knowlton & Squire, 1993). However, alternative interpretations are that: i) even people with impairments to a single memory system have sufficient resources to succeed on the particular categorization tasks that have been tested (Nosofsky & Zaki, 1998; Zaki & Nosofsky, 2001); and ii) working memory can be used at time of test to learn the categories (Palmeri & Flanery, 1999). In the present experiments, patients with amnestic mild cognitive impairment or early Alzheimer’s disease were tested in prototype-extraction tasks to examine these possibilities. In a categorization task involving discrete-feature stimuli, the majority of subjects relied on memories for exceedingly few features, even when the task structure strongly encouraged reliance on broad-based prototypes. In a dot-pattern categorization task, even the memory-impaired patients were able to use working memory at time of test to extract the category structure (at least for the stimulus set used in past work). We argue that the results weaken the past case made in favor of a separate system of implicit-prototype extraction. PMID:22746953

Causes and consequences of limitations in visual working memory.

PubMed

Fallon, Sean James; Zokaei, Nahid; Husain, Masud

2016-04-01

Recent methodological and conceptual advances have led to a fundamental reappraisal of the nature of visual working memory (WM). A large corpus of evidence now suggests that there might not be a hard limit on the number of items that can be stored. Instead, WM may be better captured by a highly limited--but flexible--resource model. More resource can be allocated to prioritized items but, crucially, at a cost of reduced recall precision for other stored items. Expectations may modulate resource distribution, for example, through neural oscillations in the alpha band increasing inhibition of irrelevant cortical regions. Our understanding of the neural architecture of WM is also undergoing radical revision. Whereas the prefrontal cortex has previously dominated research endeavors, other cortical regions, such as early visual areas, are now considered to make an essential contribution, for example holding one or more items in a privileged state or "focus of attention" within WM. By contrast, the striatum is increasingly viewed as crucial in determining why and how items are gated into memory, while the hippocampus, it has controversially been argued, might be critical in the formation of temporally resilient conjunctions across features of stored items in WM. © 2016 The Authors. Annals of the New York Academy of Sciences published by Wiley Periodicals Inc. on behalf of The New York Academy of Sciences.

Daydreaming style moderates the relation between working memory and mind wandering: Integrating two hypotheses.

PubMed

Marcusson-Clavertz, David; Cardeña, Etzel; Terhune, Devin Blair

2016-03-01

Mind wandering-mentation unrelated to one's current activity and surroundings-is a ubiquitous phenomenon, but seemingly competing ideas have been proposed regarding its relation to executive cognitive processes. The control-failure hypothesis postulates that executive processes prevent mind wandering, whereas the global availability hypothesis proposes that mind wandering requires executive resources, and thus an excess of such resources enables mind wandering. Here, we examined whether these hypotheses could be reconciled by considering the moderating influence of daydreaming style. We expected that executive resources would be positively related to mind wandering in those who typically experience positive mind wandering mentation, but negatively related in those who typically experience negative mentation. One hundred eleven participants reported mind wandering over 4 days using experience sampling and completed the sustained attention to response task (SART), the symmetry span task, and the Stroop task. There was a significant interaction between working memory and negative, but not positive, daydreaming style on mind wandering: Working memory related positively to mind wandering in those with a low negative style, but negatively in those with a high negative style. In contrast, poor Stroop performance significantly predicted increased mind wandering, but only in those with a low positive style. SART responses did not predict mind wandering although the relation was suggestively enhanced as the difficulty of daily life activities increased, indicating that the SART is more generalizable to high-demanding than low-demanding activities. These results suggest that the content and context of mind wandering episodes play important roles in the relation between executive processes and mind wandering. (c) 2016 APA, all rights reserved).

Fine motor movements while drawing during the encoding phase of a serial verbal recall task reduce working memory performance.

PubMed

Tindle, Richard; Longstaff, Mitchell G

2016-02-01

The time-based resource-sharing (TBRS) model of working memory indicates that secondary tasks that capture attention for relatively long periods can result in the interference of working memory processing and maintenance. The current study investigates if discrete and continuous movements have differing effects on a concurrent, verbal serial recall task. In the listening condition, participants were asked to recall spoken words presented in lists of six. In the drawing conditions, participants performed the same task while producing discrete (star) or continuous (circle) movements. As hypothesised, participants recalled more words overall in the listening condition compared to the combined drawing conditions. The prediction that the continuous movement condition would reduce recall compared to listening was also supported. Fine-grained analysis at each serial position revealed significantly more words were recalled at mid serial positions in the listening condition, with worst recall for the continuous condition at position 5 compared to the listening and discrete conditions. Kinematic analysis showed that participants increased the size and speed of the continuous movements resulting in a similar duration and number of strokes for each condition. The duration of brief pauses in the discrete condition was associated with the number of words recalled. The results indicate that fine motor movements reduced working memory performance; however, it was not merely performing a movement but the type of the movement that determined how resources were diverted. In the context of the TBRS, continuous movements could be capturing attention for longer periods relative to discrete movements, reducing verbal serial recall. Copyright © 2016 Elsevier B.V. All rights reserved.

To hear or not to hear: Voice processing under visual load.

PubMed

Zäske, Romi; Perlich, Marie-Christin; Schweinberger, Stefan R

2016-07-01

Adaptation to female voices causes subsequent voices to be perceived as more male, and vice versa. This contrastive aftereffect disappears under spatial inattention to adaptors, suggesting that voices are not encoded automatically. According to Lavie, Hirst, de Fockert, and Viding (2004), the processing of task-irrelevant stimuli during selective attention depends on perceptual resources and working memory. Possibly due to their social significance, faces may be an exceptional domain: That is, task-irrelevant faces can escape perceptual load effects. Here we tested voice processing, to study whether voice gender aftereffects (VGAEs) depend on low or high perceptual (Exp. 1) or working memory (Exp. 2) load in a relevant visual task. Participants adapted to irrelevant voices while either searching digit displays for a target (Exp. 1) or recognizing studied digits (Exp. 2). We found that the VGAE was unaffected by perceptual load, indicating that task-irrelevant voices, like faces, can also escape perceptual-load effects. Intriguingly, the VGAE was increased under high memory load. Therefore, visual working memory load, but not general perceptual load, determines the processing of task-irrelevant voices.

Similarity to the self influences cortical recruitment during impression formation

PubMed Central

Leshikar, Eric D.; Cassidy, Brittany S.; Gutchess, Angela H.

2015-01-01

Prior work has shown that whether or not someone is similar to the self influences person memory—a type of self-reference effect for others. In this study, we were interested in understanding the neural regions supporting the generation of impressions and subsequent memory for targets who vary in similarity to the self. Participants underwent fMRI scanning while forming positive or negative impressions of face-behavior pairs. We tested participants’ memory for their generated impressions, and then back-sorted the impression trials (encoding) into different levels of self-similarity (high, medium, low) using a self-similarity post-test that came after recognition. Extending prior behavioral work, our data confirmed our hypothesis that memory would be highest for self-similar others and lowest for self-dissimilar others. Dorsal anterior cingulate cortex (dACC) activity increased with self-similarity (high > medium > low) to targets, regardless of later memory for them. An analysis of regions supporting impression memory revealed a double dissociation within medial temporal lobe regions: for similar others, amygdala recruitment supported memory, whereas for dissimilar others, hippocampal activation supported memory. These results suggest that self-similarity influences evaluation and memory for targets, but also affects the underlying neural resources engaged when thinking about others who vary in self-similarity. PMID:26558615

A two-phase model of resource allocation in visual working memory.

PubMed

Ye, Chaoxiong; Hu, Zhonghua; Li, Hong; Ristaniemi, Tapani; Liu, Qiang; Liu, Taosheng

2017-10-01

Two broad theories of visual working memory (VWM) storage have emerged from current research, a discrete slot-based theory and a continuous resource theory. However, neither the discrete slot-based theory or continuous resource theory clearly stipulates how the mental commodity for VWM (discrete slot or continuous resource) is allocated. Allocation may be based on the number of items via stimulus-driven factors, or it may be based on task demands via voluntary control. Previous studies have obtained conflicting results regarding the automaticity versus controllability of such allocation. In the current study, we propose a two-phase allocation model, in which the mental commodity could be allocated only by stimulus-driven factors in the early consolidation phase. However, when there is sufficient time to complete the early phase, allocation can enter the late consolidation phase, where it can be flexibly and voluntarily controlled according to task demands. In an orientation recall task, we instructed participants to store either fewer items at high-precision or more items at low-precision. In 3 experiments, we systematically manipulated memory set size and exposure duration. We did not find an effect of task demands when the set size was high and exposure duration was short. However, when we either decreased the set size or increased the exposure duration, we found a trade-off between the number and precision of VWM representations. These results can be explained by a two-phase model, which can also account for previous conflicting findings in the literature. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Unraveling Network-induced Memory Contention: Deeper Insights with Machine Learning

DOE PAGES

Groves, Taylor Liles; Grant, Ryan; Gonzales, Aaron; ...

2017-11-21

Remote Direct Memory Access (RDMA) is expected to be an integral communication mechanism for future exascale systems enabling asynchronous data transfers, so that applications may fully utilize CPU resources while simultaneously sharing data amongst remote nodes. We examine Network-induced Memory Contention (NiMC) on Infiniband networks. We expose the interactions between RDMA, main-memory and cache, when applications and out-of-band services compete for memory resources. We then explore NiMCs resulting impact on application-level performance. For a range of hardware technologies and HPC workloads, we quantify NiMC and show that NiMCs impact grows with scale resulting in up to 3X performance degradation atmore » scales as small as 8K processes even in applications that previously have been shown to be performance resilient in the presence of noise. In addition, this work examines the problem of predicting NiMC's impact on applications by leveraging machine learning and easily accessible performance counters. This approach provides additional insights about the root cause of NiMC and facilitates dynamic selection of potential solutions. Finally, we evaluated three potential techniques to reduce NiMCs impact, namely hardware offloading, core reservation and network throttling.« less

Unraveling Network-induced Memory Contention: Deeper Insights with Machine Learning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Groves, Taylor Liles; Grant, Ryan; Gonzales, Aaron

Remote Direct Memory Access (RDMA) is expected to be an integral communication mechanism for future exascale systems enabling asynchronous data transfers, so that applications may fully utilize CPU resources while simultaneously sharing data amongst remote nodes. We examine Network-induced Memory Contention (NiMC) on Infiniband networks. We expose the interactions between RDMA, main-memory and cache, when applications and out-of-band services compete for memory resources. We then explore NiMCs resulting impact on application-level performance. For a range of hardware technologies and HPC workloads, we quantify NiMC and show that NiMCs impact grows with scale resulting in up to 3X performance degradation atmore » scales as small as 8K processes even in applications that previously have been shown to be performance resilient in the presence of noise. In addition, this work examines the problem of predicting NiMC's impact on applications by leveraging machine learning and easily accessible performance counters. This approach provides additional insights about the root cause of NiMC and facilitates dynamic selection of potential solutions. Finally, we evaluated three potential techniques to reduce NiMCs impact, namely hardware offloading, core reservation and network throttling.« less

Ecological Relevance Determines Task Priority in Older Adults' Multitasking.

PubMed

Doumas, Michail; Krampe, Ralf Th

2015-05-01

Multitasking is a challenging aspect of human behavior, especially if the concurrently performed tasks are different in nature. Several studies demonstrated pronounced performance decrements (dual-task costs) in older adults for combinations of cognitive and motor tasks. However, patterns of costs among component tasks differed across studies and reasons for participants' resource allocation strategies remained elusive. We investigated young and older adults' multitasking of a working memory task and two sensorimotor tasks, one with low (finger force control) and one with high ecological relevance (postural control). The tasks were performed in single-, dual-, and triple-task contexts. Working memory accuracy was reduced in dual-task contexts with either sensorimotor task and deteriorated further under triple-task conditions. Postural and force performance deteriorated with age and task difficulty in dual-task contexts. However, in the triple-task context with its maximum resource demands, older adults prioritized postural control over both force control and memory. Our results identify ecological relevance as the key factor in older adults' multitasking. © The Author 2013. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Binding in visual working memory: the role of the episodic buffer.

PubMed

Baddeley, Alan D; Allen, Richard J; Hitch, Graham J

2011-05-01

The episodic buffer component of working memory is assumed to play a central role in the binding of features into objects, a process that was initially assumed to depend upon executive resources. Here, we review a program of work in which we specifically tested this assumption by studying the effects of a range of attentionally demanding concurrent tasks on the capacity to encode and retain both individual features and bound objects. We found no differential effect of concurrent load, even when the process of binding was made more demanding by separating the shape and color features spatially, temporally or across visual and auditory modalities. Bound features were however more readily disrupted by subsequent stimuli, a process we studied using a suffix paradigm. This suggested a need to assume a feature-based attentional filter followed by an object based storage process. Our results are interpreted within a modified version of the multicomponent working memory model. We also discuss work examining the role of the hippocampus in visual feature binding. Copyright © 2011 Elsevier Ltd. All rights reserved.

Physicians’ perceptions of capacity building for managing chronic disease in seniors using integrated interprofessional care models

PubMed Central

Lee, Linda; Heckman, George; McKelvie, Robert; Jong, Philip; D’Elia, Teresa; Hillier, Loretta M.

2015-01-01

Abstract Objective To explore the barriers to and facilitators of adapting and expanding a primary care memory clinic model to integrate care of additional complex chronic geriatric conditions (heart failure, falls, chronic obstructive pulmonary disease, and frailty) into care processes with the goal of improving outcomes for seniors. Design Mixed-methods study using quantitative (questionnaires) and qualitative (interviews) methods. Setting Ontario. Participants Family physicians currently working in primary care memory clinic teams and supporting geriatric specialists. Methods Family physicians currently working in memory clinic teams (n = 29) and supporting geriatric specialists (n = 9) were recruited as survey participants. Interviews were conducted with memory clinic lead physicians (n = 16). Statistical analysis was done to assess differences between family physician ratings and geriatric specialist ratings related to the capacity for managing complex chronic geriatric conditions, the role of interprofessional collaboration within primary care, and funding and staffing to support geriatric care. Results from both study methods were compared to identify common findings. Main findings Results indicate overall support for expanding the memory clinic model to integrate care for other complex conditions. However, the current primary care structure is challenged to support optimal management of patients with multiple comorbidities, particularly as related to limited funding and staffing resources. Structured training, interprofessional teams, and an active role of geriatric specialists within primary care were identified as important facilitators. Conclusion The memory clinic model, as applied to other complex chronic geriatric conditions, has the potential to build capacity for high-quality primary care, improve health outcomes, promote efficient use of health care resources, and reduce health care costs. PMID:25932482

Effects of levodopa on corticostriatal circuits supporting working memory in Parkinson's disease.

PubMed

Simioni, Alison C; Dagher, Alain; Fellows, Lesley K

2017-08-01

Working memory dysfunction is common in Parkinson's disease, even in its early stages, but its neural basis is debated. Working memory performance likely reflects a balance between corticostriatal dysfunction and compensatory mechanisms. We tested this hypothesis by examining working memory performance with a letter n-back task in 19 patients with mild-moderate Parkinson's disease and 20 demographically matched healthy controls. Parkinson's disease patients were tested after an overnight washout of their usual dopamine replacement therapy, and again after a standard dose of levodopa. FMRI was used to assess task-related activation and resting state functional connectivity; changes in BOLD signal were related to performance to disentangle pathological and compensatory processes. Parkinson's disease patients off dopamine replacement therapy displayed significantly reduced spatial extent of task-related activation in left prefrontal and bilateral parietal cortex, and poorer working memory performance, compared to controls. Amongst the Parkinson's disease patients off dopamine replacement therapy, relatively better performance was associated with greater activation of right dorsolateral prefrontal cortex compared to controls, consistent with compensatory right hemisphere recruitment. Administration of levodopa remediated the working memory deficit in the Parkinson's disease group, and resulted in a different pattern of performance-correlated activity, with a shift to greater left ventrolateral prefrontal cortex activation in patients on, compared to off dopamine replacement therapy. Levodopa also significantly increased resting-state functional connectivity between caudate and right parietal cortex (within the right fronto-parietal attentional network). The strength of this connectivity contributed to better performance in patients and controls, suggesting a general compensatory mechanism. These findings argue that Parkinson's disease patients can recruit additional neural resources, here, the right fronto-parietal network, to optimize working memory performance despite impaired corticostriatal function. Levodopa seems to both boost engagement of a task-specific prefrontal region, and strengthen a putative compensatory caudate-cortical network to support this executive function. Copyright © 2017 Elsevier Ltd. All rights reserved.

Task set induces dynamic reallocation of resources in visual short-term memory.

PubMed

Sheremata, Summer L; Shomstein, Sarah

2017-08-01

Successful interaction with the environment requires the ability to flexibly allocate resources to different locations in the visual field. Recent evidence suggests that visual short-term memory (VSTM) resources are distributed asymmetrically across the visual field based upon task demands. Here, we propose that context, rather than the stimulus itself, determines asymmetrical distribution of VSTM resources. To test whether context modulates the reallocation of resources to the right visual field, task set, defined by memory-load, was manipulated to influence visual short-term memory performance. Performance was measured for single-feature objects embedded within predominantly single- or two-feature memory blocks. Therefore, context was varied to determine whether task set directly predicts changes in visual field biases. In accord with the dynamic reallocation of resources hypothesis, task set, rather than aspects of the physical stimulus, drove improvements in performance in the right- visual field. Our results show, for the first time, that preparation for upcoming memory demands directly determines how resources are allocated across the visual field.

Memory performance on the Auditory Inference Span Test is independent of background noise type for young adults with normal hearing at high speech intelligibility

PubMed Central

Rönnberg, Niklas; Rudner, Mary; Lunner, Thomas; Stenfelt, Stefan

2014-01-01

Listening in noise is often perceived to be effortful. This is partly because cognitive resources are engaged in separating the target signal from background noise, leaving fewer resources for storage and processing of the content of the message in working memory. The Auditory Inference Span Test (AIST) is designed to assess listening effort by measuring the ability to maintain and process heard information. The aim of this study was to use AIST to investigate the effect of background noise types and signal-to-noise ratio (SNR) on listening effort, as a function of working memory capacity (WMC) and updating ability (UA). The AIST was administered in three types of background noise: steady-state speech-shaped noise, amplitude modulated speech-shaped noise, and unintelligible speech. Three SNRs targeting 90% speech intelligibility or better were used in each of the three noise types, giving nine different conditions. The reading span test assessed WMC, while UA was assessed with the letter memory test. Twenty young adults with normal hearing participated in the study. Results showed that AIST performance was not influenced by noise type at the same intelligibility level, but became worse with worse SNR when background noise was speech-like. Performance on AIST also decreased with increasing memory load level. Correlations between AIST performance and the cognitive measurements suggested that WMC is of more importance for listening when SNRs are worse, while UA is of more importance for listening in easier SNRs. The results indicated that in young adults with normal hearing, the effort involved in listening in noise at high intelligibility levels is independent of the noise type. However, when noise is speech-like and intelligibility decreases, listening effort increases, probably due to extra demands on cognitive resources added by the informational masking created by the speech fragments and vocal sounds in the background noise. PMID:25566159

Memory performance on the Auditory Inference Span Test is independent of background noise type for young adults with normal hearing at high speech intelligibility.

PubMed

Rönnberg, Niklas; Rudner, Mary; Lunner, Thomas; Stenfelt, Stefan

2014-01-01

Listening in noise is often perceived to be effortful. This is partly because cognitive resources are engaged in separating the target signal from background noise, leaving fewer resources for storage and processing of the content of the message in working memory. The Auditory Inference Span Test (AIST) is designed to assess listening effort by measuring the ability to maintain and process heard information. The aim of this study was to use AIST to investigate the effect of background noise types and signal-to-noise ratio (SNR) on listening effort, as a function of working memory capacity (WMC) and updating ability (UA). The AIST was administered in three types of background noise: steady-state speech-shaped noise, amplitude modulated speech-shaped noise, and unintelligible speech. Three SNRs targeting 90% speech intelligibility or better were used in each of the three noise types, giving nine different conditions. The reading span test assessed WMC, while UA was assessed with the letter memory test. Twenty young adults with normal hearing participated in the study. Results showed that AIST performance was not influenced by noise type at the same intelligibility level, but became worse with worse SNR when background noise was speech-like. Performance on AIST also decreased with increasing memory load level. Correlations between AIST performance and the cognitive measurements suggested that WMC is of more importance for listening when SNRs are worse, while UA is of more importance for listening in easier SNRs. The results indicated that in young adults with normal hearing, the effort involved in listening in noise at high intelligibility levels is independent of the noise type. However, when noise is speech-like and intelligibility decreases, listening effort increases, probably due to extra demands on cognitive resources added by the informational masking created by the speech fragments and vocal sounds in the background noise.

In search for instructional techniques to maximize the use of germane cognitive resources: A case of teaching complex tasks in physics

NASA Astrophysics Data System (ADS)

Sliva, Yekaterina

The purpose of this study was to introduce an instructional technique for teaching complex tasks in physics, test its effectiveness and efficiency, and understand cognitive processes taking place in learners' minds while they are exposed to this technique. The study was based primarily on cognitive load theory (CLT). CLT determines the amount of total cognitive load imposed on a learner by a learning task as combined intrinsic (invested in comprehending task complexity) and extraneous (wasteful) cognitive load. Working memory resources associated with intrinsic cognitive load are defined as germane resources caused by element interactivity that lead to learning, in contrast to extraneous working memory resources that are devoted to dealing with extraneous cognitive load. However, the amount of learner's working memory resources actually devoted to a task depends on how well the learner is engaged in the learning environment. Since total cognitive load has to stay within limits of working memory capacity, both extraneous and intrinsic cognitive load need to be reduced. In order for effective learning to occur, the use of germane cognitive resources should be maximized. In this study, the use of germane resources was maximized for two experimental groups by providing a learning environment that combined problem-solving procedure with prompts to self-explain with and without completion problems. The study tested three hypotheses and answered two research questions. The first hypothesis predicting that experimental treatments would reduce total cognitive load was not supported. The second hypothesis predicting that experimental treatments would increase performance was supported for the self-explanation group only. The third hypothesis that tested efficiency measure as adopted from Paas and van Merrienboer (1993) was not supported. As for the research question of whether the quality of self-explanations would change with time for the two experimental conditions, it was determined that time had a positive effect on such quality. The research question that investigated learners' attitudes towards the instructions revealed that experimental groups understood the main idea behind the suggested technique and positively reacted to it. The results of the study support the conclusions that (a) prompting learners to self-explain while independently solving problems can increase performance, especially on far transfer questions; (b) better performance is achieved in combination with increased mental effort; (c) self-explanations do not increase time on task; and (d) quality of self-explanations can be improved with time. Results based on the analyses of learners' attitudes further support that learners in the experimental groups understood the main idea behind the suggested techniques and positively reacted to them. The study also raised concern about application of efficiency formula for instructional conditions that increase both performance and mental effort in CLT. As a result, an alternative model was suggested to explain the relationship between performance and mental effort based on Yerkes-Dodson law (1908). Keywords: instructional design, cognitive load, complex tasks, problem-solving, self-explanation.

An Event Related Potentials Study of the Effects of Age, Load and Maintenance Duration on Working Memory Recognition.

PubMed

Pinal, Diego; Zurrón, Montserrat; Díaz, Fernando

2015-01-01

Age-related decline in cognitive capacities has been attributed to a generalized slowing of processing speed and a reduction in working memory (WM) capacity. Nevertheless, it is unclear how age affects visuospatial WM recognition and its underlying brain electrical activity. Whether age modulates the effects of memory load or information maintenance duration, which determine the limits of WM, remains also elusive. In this exploratory study, performance in a delayed match to sample task declined with age, particularly in conditions with high memory load. Event related potentials analysis revealed longer N2 and P300 latencies in old than in young adults during WM recognition, which may reflect slowing of stimulus evaluation and classification processes, respectively. Although there were no differences between groups in N2 or P300 amplitudes, the latter was more homogeneously distributed in old than in young adults, which may indicate an age-related increased reliance in frontal vs parietal resources during WM recognition. This was further supported by an age-related reduced posterior cingulate activation and increased superior frontal gyrus activation revealed through standardized low resolution electromagnetic tomography. Memory load and maintenance duration effects on brain activity were similar in both age groups. These behavioral and electrophysiological results add evidence in support of age-related decline in WM recognition theories, with a slowing of processing speed that may be limited to stimulus evaluation and categorization processes--with no effects on perceptual processes--and a posterior to anterior shift in the recruitment of neural resources.

Prospective memory and working memory: asymmetrical effects during frontal lobe TMS stimulation.

PubMed

Basso, Demis; Ferrari, Marcella; Palladino, Paola

2010-09-01

The role of working memory (WM) for the realization of an intended action (prospective memory, PM) has been debated in recent neuropsychological literature. The present study aimed to assess whether WM and PM share resources or are, alternatively, two distinct mechanisms. A verbal task was used, which manipulated the cognitive demand of both WM and PM dimensions on an event-based prospective task. Transcranial magnetic stimulation (TMS) was also employed to clarify the causal contribution of frontal areas previously related to WM, to the PM process. The prospective task required the participant to respond whenever a word appeared which had been presented before the beginning of the task. Two ongoing tasks were administered: an updating WM task (in two conditions of medium and high WM demands) and a lexical decision task (representing a low WM demand). In the first two experiments, higher PM demand affected WM only at higher loads, but the PM load effect was independent of WM, showing asymmetrical behavioural effects. In the third experiment, single pulse TMS was applied to left and right dorsolateral prefrontal cortices. When applied to the experimental sites, stimulation increased error rates of the PM task, while the effect was only marginal in the WM task. The effect was bilateral, since there was no difference between left and right stimulation sites. These findings demonstrated, from both behavioural and neurofunctional perspectives, that WM and PM processes are not based on the same memory system, but PM may require WM resources at high demand. Copyright 2010 Elsevier Ltd. All rights reserved.

An Event Related Potentials Study of the Effects of Age, Load and Maintenance Duration on Working Memory Recognition

PubMed Central

Pinal, Diego; Zurrón, Montserrat; Díaz, Fernando

2015-01-01

Age-related decline in cognitive capacities has been attributed to a generalized slowing of processing speed and a reduction in working memory (WM) capacity. Nevertheless, it is unclear how age affects visuospatial WM recognition and its underlying brain electrical activity. Whether age modulates the effects of memory load or information maintenance duration, which determine the limits of WM, remains also elusive. In this exploratory study, performance in a delayed match to sample task declined with age, particularly in conditions with high memory load. Event related potentials analysis revealed longer N2 and P300 latencies in old than in young adults during WM recognition, which may reflect slowing of stimulus evaluation and classification processes, respectively. Although there were no differences between groups in N2 or P300 amplitudes, the latter was more homogeneously distributed in old than in young adults, which may indicate an age-related increased reliance in frontal vs parietal resources during WM recognition. This was further supported by an age-related reduced posterior cingulate activation and increased superior frontal gyrus activation revealed through standardized low resolution electromagnetic tomography. Memory load and maintenance duration effects on brain activity were similar in both age groups. These behavioral and electrophysiological results add evidence in support of age-related decline in WM recognition theories, with a slowing of processing speed that may be limited to stimulus evaluation and categorization processes -with no effects on perceptual processes- and a posterior to anterior shift in the recruitment of neural resources. PMID:26569113

The Integration of Realistic Episodic Memories Relies on Different Working Memory Processes: Evidence from Virtual Navigation.

PubMed

Plancher, Gaën; Gyselinck, Valérie; Piolino, Pascale

2018-01-01

Memory is one of the most important cognitive functions in a person's life as it is essential for recalling personal memories and performing many everyday tasks. Although a huge number of studies have been conducted in the field, only a few of them investigated memory in realistic situations, due to methodological issues. The various tools that have been developed using virtual environments (VEs) have gained popularity in cognitive psychology and neuropsychology because they enable to create naturalistic and controlled situations, and are thus particularly adapted to the study of episodic memory (EM), for which an ecological evaluation is of prime importance. EM is the conscious recollection of personal events combined with their phenomenological and spatiotemporal encoding contexts. Using an original paradigm in a VE, the objective of the present study was to characterize the construction of episodic memories. While the concept of working memory has become central in the understanding of a wide range of cognitive functions, its role in the integration of episodic memories has seldom been assessed in an ecological context. This experiment aimed at filling this gap by studying how EM is affected by concurrent tasks requiring working memory resources in a realistic situation. Participants navigated in a virtual town and had to memorize as many elements in their spatiotemporal context as they could. During learning, participants had either to perform a concurrent task meant to prevent maintenance through the phonological loop, or a task aimed at preventing maintenance through the visuospatial sketchpad, or no concurrent task. EM was assessed in a recall test performed after learning through various scores measuring the what, where and when of the memories. Results showed that, compared to the control condition with no concurrent task, the prevention of maintenance through the phonological loop had a deleterious impact only on the encoding of central elements. By contrast, the prevention of visuo-spatial maintenance interfered both with the encoding of the temporal context and with the binding. These results suggest that the integration of realistic episodic memories relies on different working memory processes that depend on the nature of the traces.

Short-term memory and dual task performance

NASA Technical Reports Server (NTRS)

Regan, J. E.

1982-01-01

Two hypotheses concerning the way in which short-term memory interacts with another task in a dual task situation are considered. It is noted that when two tasks are combined, the activity of controlling and organizing performance on both tasks simultaneously may compete with either task for a resource; this resource may be space in a central mechanism or general processing capacity or it may be some task-specific resource. If a special relationship exists between short-term memory and control, especially if there is an identity relationship between short-term and a central controlling mechanism, then short-term memory performance should show a decrement in a dual task situation. Even if short-term memory does not have any particular identity with a controlling mechanism, but both tasks draw on some common resource or resources, then a tradeoff between the two tasks in allocating resources is possible and could be reflected in performance. The persistent concurrence cost in memory performance in these experiments suggests that short-term memory may have a unique status in the information processing system.

Language aptitude for pronunciation in advanced second language (L2) learners: behavioural predictors and neural substrates.

PubMed

Hu, Xiaochen; Ackermann, Hermann; Martin, Jason A; Erb, Michael; Winkler, Susanne; Reiterer, Susanne M

2013-12-01

Individual differences in second language (L2) aptitude have been assumed to depend upon a variety of cognitive and personality factors. Especially, the cognitive factor phonological working memory has been conceptualised as language learning device. However, strong associations between phonological working memory and L2 aptitude have been previously found in early-stage learners only, not in advanced learners. The current study aimed at investigating the behavioural and neurobiological predictors of advanced L2 learning. Our behavioural results showed that phonetic coding ability and empathy, but not phonological working memory, predict L2 pronunciation aptitude in advanced learners. Second, functional neuroimaging revealed this behavioural trait to be correlated with hemodynamic responses of the cerebral network of speech motor control and auditory-perceptual areas. We suggest that the acquisition of L2 pronunciation aptitude is a dynamic process, requiring a variety of neural resources at different processing stages over time. Copyright © 2012 Elsevier Inc. All rights reserved.

Working memory and inhibitory control across the life span: Intrusion errors in the Reading Span Test.

PubMed

Robert, Christelle; Borella, Erika; Fagot, Delphine; Lecerf, Thierry; de Ribaupierre, Anik

2009-04-01

The aim of this study was to examine to what extent inhibitory control and working memory capacity are related across the life span. Intrusion errors committed by children and younger and older adults were investigated in two versions of the Reading Span Test. In Experiment 1, a mixed Reading Span Test with items of various list lengths was administered. Older adults and children recalled fewer correct words and produced more intrusions than did young adults. Also, age-related differences were found in the type of intrusions committed. In Experiment 2, an adaptive Reading Span Test was administered, in which the list length of items was adapted to each individual's working memory capacity. Age groups differed neither on correct recall nor on the rate of intrusions, but they differed on the type of intrusions. Altogether, these findings indicate that the availability of attentional resources influences the efficiency of inhibition across the life span.

Domain-Specific Interference Tests on Navigational Working Memory in Military Pilots.

PubMed

Verde, Paola; Boccia, Maddalena; Colangeli, Stefano; Barbetti, Sonia; Nori, Raffaella; Ferlazzo, Fabio; Piccolo, Francesco; Vitalone, Roberto; Lucertini, Elena; Piccardi, Laura

2016-06-01

Human navigation is a very complex ability that encompasses all four stages of human information processing (sensory input, perception/cognition, selection, and execution of an action), involving both cognitive and physical requirements. During flight, the pilot uses all of these stages and one of the most critical aspect is interference. In fact, spatial tasks competing for the same cognitive resource cause greater distraction from a concurrent task than another task that uses different resource modalities. Here we compared and contrasted the performance of pilots and nonpilots of both genders performing increasingly complex navigational memory tasks while exposed to various forms of interference. We investigated the effects of four different sources of interference: motor, spatial motor, verbal, and spatial environment, focusing on gender differences. We found that flight experts perform better than controls (Pilots: 6.50 ± 1.29; Nonpilots: 5.45 ± 1.41). Furthermore, in the general population, navigational working memory is compromised only by spatial environmental interference (Nonpilots: 4.52 ± 1.50); female nonpilots were less able than male nonpilots. Also, the flight expert group showed the same interference, even if reduced (Pilots: 5.24 ± 0.92); moreover, we highlighted a complete absence of gender-related effects. Spatial environmental interference is the only interference producing a decrease in performance. Nevertheless, pilots are less affected than the general population. This is probably a consequence of the need to commit substantial cognitive resources to process spatial information during flight.

How Managers' everyday decisions create or destroy your company's strategy.

PubMed

Bower, Joseph L; Gilbert, Clark G

2007-02-01

Senior executives have long been frustrated by the disconnection between the plans and strategies they devise and the actual behavior of the managers throughout the company. This article approaches the problem from the ground up, recognizing that every time a manager allocates resources, that decision moves the company either into or out of alignment with its announced strategy. A well-known story--Intel's exit from the memory business--illustrates this point. When discussing what businesses Intel should be in, Andy Grove asked Gordon Moore what they would do if Intel were a company that they had just acquired. When Moore answered, "Get out of memory," they decided to do just that. It turned out, though, that Intel's revenues from memory were by this time only 4% of total sales. Intel's lower-level managers had already exited the business. What Intel hadn't done was to shut down the flow of research funding into memory (which was still eating up one-third of all research expenditures); nor had the company announced its exit to the outside world. Because divisional and operating managers-as well as customers and capital markets-have such a powerful impact on the realized strategy of the firm, senior management might consider focusing less on the company's formal strategy and more on the processes by which the company allocates resources. Top managers must know the track record of the people who are making resource allocation proposals; recognize the strategic issues at stake; reach down to operational managers to work across division lines; frame resource questions to reflect the corporate perspective, especially when large sums of money are involved and conditions are highly uncertain; and create a new context that allows top executives to circumvent the regular resource allocation process when necessary.

Neural hyperactivity related to working memory in drug-naive boys with attention deficit hyperactivity disorder.

PubMed

Li, Yuanyuan; Li, Fei; He, Ning; Guo, Lanting; Huang, Xiaoqi; Lui, Su; Gong, Qiyong

2014-08-04

Impaired working memory is thought to be a core feature of attention deficit hyperactivity disorder (ADHD). Previous imaging studies investigating working memory in ADHD have used tasks involving different cognitive resources and ignoring the categorical judgments about objects that are essential parts of performance in visual working memory tasks, thus complicating the interpretation of their findings. In the present study, we explored differential neural activation in children and adolescents with ADHD and in healthy controls using functional magnetic resonance imaging (fMRI) with the categorical n-back task (CN-BT), which maximized demands for executive reasoning while holding memory demands constant. A total of 33 drug-naive, right-handed male ADHD without comorbidity (mean age 9.9±2.4 years) and 27 right-handed, healthy male controls (mean age 10.9±2.7 years) were recruited in the present study. Event-related fMRI was used to study differences in brain activity during the CN-BT between the two groups. The two groups did not differ in their accuracy in the CN-BT, although the ADHD patients showed significantly shorter reaction times to correct responses than did the controls. During the CN-BT, both ADHD patients and controls showed significant positive and negative activations by the correct responses, mainly in the sensory-motor pathways and the striato-cerebellum circuit. Additionally, the ADHD patients showed significantly higher activation in the bilateral globus pallidus and the right hippocampus compared with the controls. There was also a positive correlation between hyperactivation of the left globus pallidus and the reaction time to correct responses in ADHD. In contrast to controls, ADHD patients showed neural hyperactivation in the striatum and mediotemporal areas during a working memory task involving categorization. Hyperfunction in these areas might be the pathophysiological foundation of ADHD, related to the deficits of working memory and the impulsive symptoms. Copyright © 2014 Elsevier Inc. All rights reserved.

Resource-sharing between internal maintenance and external selection modulates attentional capture by working memory content.

PubMed

Kiyonaga, Anastasia; Egner, Tobias

2014-01-01

It is unclear why and under what circumstances working memory (WM) and attention interact. Here, we apply the logic of the time-based resource-sharing (TBRS) model of WM (e.g., Barrouillet et al., 2004) to explore the mixed findings of a separate, but related, literature that studies the guidance of visual attention by WM contents. Specifically, we hypothesize that the linkage between WM representations and visual attention is governed by a time-shared cognitive resource that alternately refreshes internal (WM) and selects external (visual attention) information. If this were the case, WM content should guide visual attention (involuntarily), but only when there is time for it to be refreshed in an internal focus of attention. To provide an initial test for this hypothesis, we examined whether the amount of unoccupied time during a WM delay could impact the magnitude of attentional capture by WM contents. Participants were presented with a series of visual search trials while they maintained a WM cue for a delayed-recognition test. WM cues could coincide with the search target, a distracter, or neither. We varied both the number of searches to be performed, and the amount of available time to perform them. Slowing of visual search by a WM matching distracter-and facilitation by a matching target-were curtailed when the delay was filled with fast-paced (refreshing-preventing) search trials, as was subsequent memory probe accuracy. WM content may, therefore, only capture visual attention when it can be refreshed, suggesting that internal (WM) and external attention demands reciprocally impact one another because they share a limited resource. The TBRS rationale can thus be applied in a novel context to explain why WM contents capture attention, and under what conditions that effect should be observed.

Resource-sharing between internal maintenance and external selection modulates attentional capture by working memory content

PubMed Central

Kiyonaga, Anastasia; Egner, Tobias

2014-01-01

It is unclear why and under what circumstances working memory (WM) and attention interact. Here, we apply the logic of the time-based resource-sharing (TBRS) model of WM (e.g., Barrouillet et al., 2004) to explore the mixed findings of a separate, but related, literature that studies the guidance of visual attention by WM contents. Specifically, we hypothesize that the linkage between WM representations and visual attention is governed by a time-shared cognitive resource that alternately refreshes internal (WM) and selects external (visual attention) information. If this were the case, WM content should guide visual attention (involuntarily), but only when there is time for it to be refreshed in an internal focus of attention. To provide an initial test for this hypothesis, we examined whether the amount of unoccupied time during a WM delay could impact the magnitude of attentional capture by WM contents. Participants were presented with a series of visual search trials while they maintained a WM cue for a delayed-recognition test. WM cues could coincide with the search target, a distracter, or neither. We varied both the number of searches to be performed, and the amount of available time to perform them. Slowing of visual search by a WM matching distracter—and facilitation by a matching target—were curtailed when the delay was filled with fast-paced (refreshing-preventing) search trials, as was subsequent memory probe accuracy. WM content may, therefore, only capture visual attention when it can be refreshed, suggesting that internal (WM) and external attention demands reciprocally impact one another because they share a limited resource. The TBRS rationale can thus be applied in a novel context to explain why WM contents capture attention, and under what conditions that effect should be observed. PMID:25221499

Memory for a single object has differently variable precisions for relevant and irrelevant features.

PubMed

Swan, Garrett; Collins, John; Wyble, Brad

2016-01-01

Working memory is a limited resource. To further characterize its limitations, it is vital to understand exactly what is encoded about a visual object beyond the "relevant" features probed in a particular task. We measured the memory quality of a task-irrelevant feature of an attended object by coupling a delayed estimation task with a surprise test. Participants were presented with a single colored arrow and were asked to retrieve just its color for the first half of the experiment before unexpectedly being asked to report its direction. Mixture modeling of the data revealed that participants had highly variable precision on the surprise test, indicating a coarse-grained memory for the irrelevant feature. Following the surprise test, all participants could precisely recall the arrow's direction; however, this improvement in direction memory came at a cost in precision for color memory even though only a single object was being remembered. We attribute these findings to varying levels of attention to different features during memory encoding.

Differential recruitment of executive resources during mind wandering.

PubMed

Kam, Julia W Y; Handy, Todd C

2014-05-01

Recent research has shown that mind wandering recruits executive resources away from the external task towards inner thoughts. No studies however have determined whether executive functions are drawn away in a unitary manner during mind wandering episodes, or whether there is variation in specific functions impacted. Accordingly, we examined whether mind wandering differentially modulates three core executive functions-response inhibition, updating of working memory, and mental set shifting. In three experiments, participants performed one of these three executive function tasks and reported their attentional state as either on-task or mind wandering at random intervals. We found that mind wandering led to poorer performance in the response inhibition and working memory tasks, but not the set-shifting task. These findings suggest that mind wandering does not recruit executive functions in a monolithic manner. Rather, it appears to selectively engage certain executive functions, which may reflect the adaptive maintenance of ongoing task performance. Copyright © 2014 Elsevier Inc. All rights reserved.

Coherence across consciousness levels: Symmetric visual displays spare working memory resources.

PubMed

Dumitru, Magda L

2015-12-15

Two studies demonstrate that the need for coherence could nudge individuals to use structural similarities between binary visual displays and two concurrent cognitive tasks to unduly solve the latter in similar fashion. In an overt truth-judgement task, participants decided whether symmetric colourful displays matched conjunction or disjunction descriptions (e.g., "the black and/or the orange"). In the simultaneous covert categorisation task, they decided whether a colour name (e.g., "black") described a two-colour object or half of a single-colour object. Two response patterns emerged as follows. Participants either acknowledged or rejected matches between disjunction descriptions and two visual stimuli and, similarly, either acknowledged or rejected matches between single colour names and two-colour objects or between single colour names and half of single-colour objects. These findings confirm the coherence hypothesis, highlight the role of coherence in preserving working-memory resources, and demonstrate an interaction between high-level and low-level consciousness. Copyright © 2015 Elsevier Inc. All rights reserved.

Does working memory capacity predict cross-modally induced failures of awareness?

PubMed

Kreitz, Carina; Furley, Philip; Simons, Daniel J; Memmert, Daniel

2016-01-01

People often fail to notice unexpected stimuli when they are focusing attention on another task. Most studies of this phenomenon address visual failures induced by visual attention tasks (inattentional blindness). Yet, such failures also occur within audition (inattentional deafness), and people can even miss unexpected events in one sensory modality when focusing attention on tasks in another modality. Such cross-modal failures are revealing because they suggest the existence of a common, central resource limitation. And, such central limits might be predicted from individual differences in cognitive capacity. We replicated earlier evidence, establishing substantial rates of inattentional deafness during a visual task and inattentional blindness during an auditory task. However, neither individual working memory capacity nor the ability to perform the primary task predicted noticing in either modality. Thus, individual differences in cognitive capacity did not predict failures of awareness even though the failures presumably resulted from central resource limitations. Copyright © 2015 Elsevier Inc. All rights reserved.

Mindfulness, anxiety, and high-stakes mathematics performance in the laboratory and classroom.

PubMed

Bellinger, David B; DeCaro, Marci S; Ralston, Patricia A S

2015-12-01

Mindfulness enhances emotion regulation and cognitive performance. A mindful approach may be especially beneficial in high-stakes academic testing environments, in which anxious thoughts disrupt cognitive control. The current studies examined whether mindfulness improves the emotional response to anxiety-producing testing situations, freeing working memory resources, and improving performance. In Study 1, we examined performance in a high-pressure laboratory setting. Mindfulness indirectly benefited math performance by reducing the experience of state anxiety. This benefit occurred selectively for problems that required greater working memory resources. Study 2 extended these findings to a calculus course taken by undergraduate engineering majors. Mindfulness indirectly benefited students' performance on high-stakes quizzes and exams by reducing their cognitive test anxiety. Mindfulness did not impact performance on lower-stakes homework assignments. These findings reveal an important mechanism by which mindfulness benefits academic performance, and suggest that mindfulness may help attenuate the negative effects of test anxiety. Copyright © 2015 Elsevier Inc. All rights reserved.

Independent operation of implicit working memory under cognitive load.

PubMed

Ji, Eunhee; Lee, Kyung Min; Kim, Min-Shik

2017-10-01

Implicit working memory (WM) has been known to operate non-consciously and unintentionally. The current study investigated whether implicit WM is a discrete mechanism from explicit WM in terms of cognitive resource. To induce cognitive resource competition, we used a conjunction search task (Experiment 1) and imposed spatial WM load (Experiment 2a and 2b). Each trial was composed of a set of five consecutive search displays. The location of the first four displays appeared as per pre-determined patterns, but the fifth display could follow the same pattern or not. If implicit WM can extract the moving pattern of stimuli, response times for the fifth target would be faster when it followed the pattern compared to when it did not. Our results showed implicit WM can operate when participants are searching for the conjunction target and even while maintaining spatial WM information. These results suggest that implicit WM is independent from explicit spatial WM. Copyright © 2017. Published by Elsevier Inc.

Neural circuitry governing anxious individuals' mis-allocation of working memory to threat.

PubMed

Stout, Daniel M; Shackman, Alexander J; Pedersen, Walker S; Miskovich, Tara A; Larson, Christine L

2017-08-18

Dispositional anxiety is a trait-like phenotype that confers increased risk for a range of debilitating neuropsychiatric disorders. Like many patients with anxiety disorders, individuals with elevated levels of dispositional anxiety are prone to intrusive and distressing thoughts in the absence of immediate threat. Recent electrophysiological research suggests that these symptoms are rooted in the mis-allocation of working memory (WM) resources to threat-related information. Here, functional MRI was used to identify the network of brain regions that support WM for faces and to quantify the allocation of neural resources to threat-related distracters in 81 young adults. Results revealed widespread evidence of mis-allocation. This was evident in both face-selective regions of the fusiform cortex and domain-general regions of the prefrontal and parietal cortices. This bias was exaggerated among individuals with a more anxious disposition. Mediation analyses provided compelling evidence that anxious individuals' tendency to mis-allocate WM resources to threat-related distracters is statistically explained by heightened amygdala reactivity. Collectively, these results provide a neurocognitive framework for understanding the pathways linking anxious phenotypes to the development of internalizing psychopathology and set the stage for developing improved intervention strategies.

Age-related changes in event-cued visual and auditory prospective memory proper.

PubMed

Uttl, Bob

2006-06-01

We rely upon prospective memory proper (ProMP) to bring back to awareness previously formed plans and intentions at the right place and time, and to enable us to act upon those plans and intentions. To examine age-related changes in ProMP, younger and older participants made decisions about simple stimuli (ongoing task) and at the same time were required to respond to a ProM cue, either a picture (visually cued ProM test) or a sound (auditorily cued ProM test), embedded in a simultaneously presented series of similar stimuli (either pictures or sounds). The cue display size or loudness increased across trials until a response was made. The cue size and cue loudness at the time of response indexed ProMP. The main results showed that both visual and auditory ProMP declined with age, and that such declines were mediated by age declines in sensory functions (visual acuity and hearing level), processing resources, working memory, intelligence, and ongoing task resource allocation.

Divided attention selectively impairs memory for self-relevant information.

PubMed

Turk, David J; Brady-van den Bos, Mirjam; Collard, Philip; Gillespie-Smith, Karri; Conway, Martin A; Cunningham, Sheila J

2013-05-01

Information that is relevant to oneself tends to be remembered more than information that relates to other people, but the role of attention in eliciting this "self-reference effect" is unclear. In the present study, we assessed the importance of attention in self-referential encoding using an ownership paradigm, which required participants to encode items under conditions of imagined ownership by themselves or by another person. Previous work has established that this paradigm elicits a robust self-reference effect, with more "self-owned" items being remembered than "other-owned" items. Access to attentional resources was manipulated using divided-attention tasks at encoding. A significant self-reference effect emerged under full-attention conditions and was related to an increase in episodic recollection for self-owned items, but dividing attention eliminated this memory advantage. These findings are discussed in relation to the nature of self-referential cognition and the importance of attentional resources at encoding in the manifestation of the self-reference effect in memory.

The working memory stroop effect: when internal representations clash with external stimuli.

PubMed

Kiyonaga, Anastasia; Egner, Tobias

2014-08-01

Working memory (WM) has recently been described as internally directed attention, which implies that WM content should affect behavior exactly like an externally perceived and attended stimulus. We tested whether holding a color word in WM, rather than attending to it in the external environment, can produce interference in a color-discrimination task, which would mimic the classic Stroop effect. Over three experiments, the WM Stroop effect recapitulated core properties of the classic attentional Stroop effect, displaying equivalent congruency effects, additive contributions from stimulus- and response-level congruency, and susceptibility to modulation by the percentage of congruent and incongruent trials. Moreover, WM maintenance was inversely related to attentional demands during the WM delay between stimulus presentation and recall, with poorer memory performance following incongruent than congruent trials. Together, these results suggest that WM and attention rely on the same resources and operate over the same representations. © The Author(s) 2014.

When planning results in loss of control: intention-based reflexivity and working-memory

PubMed Central

Meiran, Nachshon; Cole, Michael W.; Braver, Todd S.

2012-01-01

In this review, the authors discuss the seemingly paradoxical loss of control associated with states of high readiness to execute a plan, termed “intention-based reflexivity.” The review suggests that the neuro-cognitive systems involved in the preparation of novel plans are different than those involved in preparation of practiced plans (i.e., those that have been executed beforehand). When the plans are practiced, intention-based reflexivity depends on the prior availability of response codes in long-term memory (LTM). When the plans are novel, reflexivity is observed when the plan is pending and the goal has not yet been achieved. Intention-based reflexivity also depends on the availability of working-memory (WM) limited resources and the motivation to prepare. Reflexivity is probably related to the fact that, unlike reactive control (once a plan is prepared), proactive control tends to be relatively rigid. PMID:22586382

The relation between working memory and language comprehension in signers and speakers.

PubMed

Emmorey, Karen; Giezen, Marcel R; Petrich, Jennifer A F; Spurgeon, Erin; O'Grady Farnady, Lucinda

2017-06-01

This study investigated the relation between linguistic and spatial working memory (WM) resources and language comprehension for signed compared to spoken language. Sign languages are both linguistic and visual-spatial, and therefore provide a unique window on modality-specific versus modality-independent contributions of WM resources to language processing. Deaf users of American Sign Language (ASL), hearing monolingual English speakers, and hearing ASL-English bilinguals completed several spatial and linguistic serial recall tasks. Additionally, their comprehension of spatial and non-spatial information in ASL and spoken English narratives was assessed. Results from the linguistic serial recall tasks revealed that the often reported advantage for speakers on linguistic short-term memory tasks does not extend to complex WM tasks with a serial recall component. For English, linguistic WM predicted retention of non-spatial information, and both linguistic and spatial WM predicted retention of spatial information. For ASL, spatial WM predicted retention of spatial (but not non-spatial) information, and linguistic WM did not predict retention of either spatial or non-spatial information. Overall, our findings argue against strong assumptions of independent domain-specific subsystems for the storage and processing of linguistic and spatial information and furthermore suggest a less important role for serial encoding in signed than spoken language comprehension. Copyright © 2017 Elsevier B.V. All rights reserved.

Experimentally modeling stochastic processes with less memory by the use of a quantum processor

PubMed Central

Palsson, Matthew S.; Gu, Mile; Ho, Joseph; Wiseman, Howard M.; Pryde, Geoff J.

2017-01-01

Computer simulation of observable phenomena is an indispensable tool for engineering new technology, understanding the natural world, and studying human society. However, the most interesting systems are often so complex that simulating their future behavior demands storing immense amounts of information regarding how they have behaved in the past. For increasingly complex systems, simulation becomes increasingly difficult and is ultimately constrained by resources such as computer memory. Recent theoretical work shows that quantum theory can reduce this memory requirement beyond ultimate classical limits, as measured by a process’ statistical complexity, C. We experimentally demonstrate this quantum advantage in simulating stochastic processes. Our quantum implementation observes a memory requirement of Cq = 0.05 ± 0.01, far below the ultimate classical limit of C = 1. Scaling up this technique would substantially reduce the memory required in simulations of more complex systems. PMID:28168218

A steady state visually evoked potential investigation of memory and ageing.

PubMed

Macpherson, Helen; Pipingas, Andrew; Silberstein, Richard

2009-04-01

Old age is generally accompanied by a decline in memory performance. Specifically, neuroimaging and electrophysiological studies have revealed that there are age-related changes in the neural correlates of episodic and working memory. This study investigated age-associated changes in the steady state visually evoked potential (SSVEP) amplitude and latency associated with memory performance. Participants were 15 older (59-67 years) and 14 younger (20-30 years) adults who performed an object working memory (OWM) task and a contextual recognition memory (CRM) task, whilst the SSVEP was recorded from 64 electrode sites. Retention of a single object in the low demand OWM task was characterised by smaller frontal SSVEP amplitude and latency differences in older adults than in younger adults, indicative of an age-associated reduction in neural processes. Recognition of visual images in the more difficult CRM task was accompanied by larger, more sustained SSVEP amplitude and latency decreases over temporal parietal regions in older adults. In contrast, the more transient, frontally mediated pattern of activity demonstrated by younger adults suggests that younger and older adults utilize different neural resources to perform recognition judgements. The results provide support for compensatory processes in the aging brain; at lower task demands, older adults demonstrate reduced neural activity, whereas at greater task demands neural activity is increased.

Stream-based Hebbian eigenfilter for real-time neuronal spike discrimination

PubMed Central

2012-01-01

Background Principal component analysis (PCA) has been widely employed for automatic neuronal spike sorting. Calculating principal components (PCs) is computationally expensive, and requires complex numerical operations and large memory resources. Substantial hardware resources are therefore needed for hardware implementations of PCA. General Hebbian algorithm (GHA) has been proposed for calculating PCs of neuronal spikes in our previous work, which eliminates the needs of computationally expensive covariance analysis and eigenvalue decomposition in conventional PCA algorithms. However, large memory resources are still inherently required for storing a large volume of aligned spikes for training PCs. The large size memory will consume large hardware resources and contribute significant power dissipation, which make GHA difficult to be implemented in portable or implantable multi-channel recording micro-systems. Method In this paper, we present a new algorithm for PCA-based spike sorting based on GHA, namely stream-based Hebbian eigenfilter, which eliminates the inherent memory requirements of GHA while keeping the accuracy of spike sorting by utilizing the pseudo-stationarity of neuronal spikes. Because of the reduction of large hardware storage requirements, the proposed algorithm can lead to ultra-low hardware resources and power consumption of hardware implementations, which is critical for the future multi-channel micro-systems. Both clinical and synthetic neural recording data sets were employed for evaluating the accuracy of the stream-based Hebbian eigenfilter. The performance of spike sorting using stream-based eigenfilter and the computational complexity of the eigenfilter were rigorously evaluated and compared with conventional PCA algorithms. Field programmable logic arrays (FPGAs) were employed to implement the proposed algorithm, evaluate the hardware implementations and demonstrate the reduction in both power consumption and hardware memories achieved by the streaming computing Results and discussion Results demonstrate that the stream-based eigenfilter can achieve the same accuracy and is 10 times more computationally efficient when compared with conventional PCA algorithms. Hardware evaluations show that 90.3% logic resources, 95.1% power consumption and 86.8% computing latency can be reduced by the stream-based eigenfilter when compared with PCA hardware. By utilizing the streaming method, 92% memory resources and 67% power consumption can be saved when compared with the direct implementation of GHA. Conclusion Stream-based Hebbian eigenfilter presents a novel approach to enable real-time spike sorting with reduced computational complexity and hardware costs. This new design can be further utilized for multi-channel neuro-physiological experiments or chronic implants. PMID:22490725

Working memory, short-term memory, and reading disabilities: a selective meta-analysis of the literature.

PubMed

Swanson, H Lee; Xinhua Zheng; Jerman, Olga

2009-01-01

The purpose of the present study was to synthesize research that compares children with and without reading disabilities (RD) on measures of short-term memory (STM) and working memory (WM). Across a broad age, reading, and IQ range, 578 effect sizes (ESs) were computed, yielding a mean ES across studies of -.89 (SD = 1.03). A total of 257 ESs were in the moderate range for STM measures (M = -.61, 95% confidence range of -.65 to -.58), and 320 ESs were in the moderate range for WM measures (M = -.67, 95% confidence range of -.68 to -.64). The results indicated that children with RD were distinctively disadvantaged compared with average readers on (a) STM measures requiring the recall of phonemes and digit sequences and (b) WM measures requiring the simultaneous processing and storage of digits within sentence sequences and final words from unrelated sentences. No significant moderating effects emerged for age, IQ, or reading level on memory ESs. The findings indicated that domain-specific STM and WM differences between ability groups persisted across age, suggesting that a verbal deficit model that fails to efficiently draw resources from both a phonological and executive system underlies RD.

Selective Attention to Auditory Memory Neurally Enhances Perceptual Precision.

PubMed

Lim, Sung-Joo; Wöstmann, Malte; Obleser, Jonas

2015-12-09

Selective attention to a task-relevant stimulus facilitates encoding of that stimulus into a working memory representation. It is less clear whether selective attention also improves the precision of a stimulus already represented in memory. Here, we investigate the behavioral and neural dynamics of selective attention to representations in auditory working memory (i.e., auditory objects) using psychophysical modeling and model-based analysis of electroencephalographic signals. Human listeners performed a syllable pitch discrimination task where two syllables served as to-be-encoded auditory objects. Valid (vs neutral) retroactive cues were presented during retention to allow listeners to selectively attend to the to-be-probed auditory object in memory. Behaviorally, listeners represented auditory objects in memory more precisely (expressed by steeper slopes of a psychometric curve) and made faster perceptual decisions when valid compared to neutral retrocues were presented. Neurally, valid compared to neutral retrocues elicited a larger frontocentral sustained negativity in the evoked potential as well as enhanced parietal alpha/low-beta oscillatory power (9-18 Hz) during memory retention. Critically, individual magnitudes of alpha oscillatory power (7-11 Hz) modulation predicted the degree to which valid retrocues benefitted individuals' behavior. Our results indicate that selective attention to a specific object in auditory memory does benefit human performance not by simply reducing memory load, but by actively engaging complementary neural resources to sharpen the precision of the task-relevant object in memory. Can selective attention improve the representational precision with which objects are held in memory? And if so, what are the neural mechanisms that support such improvement? These issues have been rarely examined within the auditory modality, in which acoustic signals change and vanish on a milliseconds time scale. Introducing a new auditory memory paradigm and using model-based electroencephalography analyses in humans, we thus bridge this gap and reveal behavioral and neural signatures of increased, attention-mediated working memory precision. We further show that the extent of alpha power modulation predicts the degree to which individuals' memory performance benefits from selective attention. Copyright © 2015 the authors 0270-6474/15/3516094-11$15.00/0.

Tinnitus and Its Effect on Working Memory and Attention

ERIC Educational Resources Information Center

Rossiter, Susan; Stevens, Catherine; Walker, Gary

2006-01-01

Purpose: In 2 experiments, the assumption that continual orienting to tinnitus uses cognitive resources was investigated. It was hypothesized that differences in performance of tinnitus and control groups would manifest during demanding or unfamiliar tasks that required strategic, controlled processing and that reduced performance was not related…

Time and Cognitive Load in Working Memory

ERIC Educational Resources Information Center

Barrouillet, Pierre; Bernardin, Sophie; Portrat, Sophie; Vergauwe, Evie; Camos, Valerie

2007-01-01

According to the time-based resource-sharing model (P. Barrouillet, S. Bernardin, & V. Camos, 2004), the cognitive load a given task involves is a function of the proportion of time during which it captures attention, thus impeding other attention-demanding processes. Accordingly, the present study demonstrates that the disruptive effect on…

Discrimination against Facially Stigmatized Applicants in Interviews: An Eye-Tracking and Face-to-Face Investigation

ERIC Educational Resources Information Center

Madera, Juan M.; Hebl, Michelle R.

2012-01-01

Drawing from theory and research on perceived stigma (Pryor, Reeder, Yeadon, & Hesson-McInnis, 2004), attentional processes (Rinck & Becker, 2006), working memory (Baddeley & Hitch, 1974), and regulatory resources (Muraven & Baumeister, 2000), the authors examined discrimination against facially stigmatized applicants and the processes involved.…

Ghosts in the Machine II: Neural Correlates of Memory Interference from the Previous Trial.

PubMed

Papadimitriou, Charalampos; White, Robert L; Snyder, Lawrence H

2017-04-01

Previous memoranda interfere with working memory. For example, spatial memories are biased toward locations memorized on the previous trial. We predicted, based on attractor network models of memory, that activity in the frontal eye fields (FEFs) encoding a previous target location can persist into the subsequent trial and that this ghost will then bias the readout of the current target. Contrary to this prediction, we find that FEF memory representations appear biased away from (not toward) the previous target location. The behavioral and neural data can be reconciled by a model in which receptive fields of memory neurons converge toward remembered locations, much as receptive fields converge toward attended locations. Convergence increases the resources available to encode the relevant memoranda and decreases overall error in the network, but the residual convergence from the previous trial can give rise to an attractive behavioral bias on the next trial. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Self-Regulatory Strategies in Daily Life: Selection, Optimization, and Compensation and Everyday Memory Problems

PubMed Central

Stephanie, Robinson; Margie, Lachman; Elizabeth, Rickenbach

2015-01-01

The effective use of self-regulatory strategies, such as selection, optimization, and compensation (SOC) requires resources. However, it is theorized that SOC use is most advantageous for those experiencing losses and diminishing resources. The present study explored this seeming paradox within the context of limitations or constraints due to aging, low cognitive resources, and daily stress in relation to everyday memory problems. We examined whether SOC usage varied by age and level of constraints, and if the relationship between resources and memory problems was mitigated by SOC usage. A daily diary paradigm was used to explore day-to-day fluctuations in these relationships. Participants (n=145, ages 22 to 94) completed a baseline interview and a daily diary for seven consecutive days. Multilevel models examined between- and within-person relationships between daily SOC use, daily stressors, cognitive resources, and everyday memory problems. Middle-aged adults had the highest SOC usage, although older adults also showed high SOC use if they had high cognitive resources. More SOC strategies were used on high stress compared to low stress days. Moreover, the relationship between daily stress and memory problems was buffered by daily SOC use, such that on high-stress days, those who used more SOC strategies reported fewer memory problems than participants who used fewer SOC strategies. The paradox of resources and SOC use can be qualified by the type of resource-limitation. Deficits in global resources were not tied to SOC usage or benefits. Conversely, under daily constraints tied to stress, the use of SOC increased and led to fewer memory problems. PMID:26997686

From Resource-Adaptive Navigation Assistance to Augmented Cognition

NASA Astrophysics Data System (ADS)

Zimmer, Hubert D.; Münzer, Stefan; Baus, Jörg

In an assistance scenario, a computer provides purposive information supporting a human user in an everyday situation. Wayfinding with navigation assistance is a prototypical assistance scenario. The present chapter analyzes the interplay of the resources of the assistance system and the resources of the user. The navigation assistance system provides geographic knowledge, positioning information, route planning, spatial overview information, and route commands at decision points. The user's resources encompass spatial knowledge, spatial abilities and visuo-spatial working memory, orientation strategies, and cultural habit. Flexible adaptations of the assistance system to available resources of the user are described, taking different wayfinding goals, situational constraints, and individual differences into account. Throughout the chapter, the idea is pursued that the available resources of the user should be kept active.

Interference Impacts Working Memory in Mild Cognitive Impairment

PubMed Central

Aurtenetxe, Sara; García-Pacios, Javier; del Río, David; López, María E.; Pineda-Pardo, José A.; Marcos, Alberto; Delgado Losada, Maria L.; López-Frutos, José M.; Maestú, Fernando

2016-01-01

Mild cognitive impairment (MCI) is considered a transitional stage between healthy aging and dementia, specifically Alzheimer's disease (AD). The most common cognitive impairment of MCI includes episodic memory loss and difficulties in working memory (WM). Interference can deplete WM, and an optimal WM performance requires an effective control of attentional resources between the memoranda and the incoming stimuli. Difficulties in handling interference lead to forgetting. However, the interplay between interference and WM in MCI is not well-understood and needs further investigation. The current study investigated the effect of interference during a WM task in 20 MCIs and 20 healthy elder volunteers. Participants performed a delayed match-to-sample paradigm which consisted in two interference conditions, distraction and interruption, and one control condition without any interference. Results evidenced a disproportionate impact of interference on the WM performance of MCIs, mainly in the presence of interruption. These findings demonstrate that interference, and more precisely interruption, is an important proxy for memory-related deficits in MCI. Thus, the current findings reveal novel evidence regarding the causes of WM forgetting in MCI patients, associated with difficulties in the mechanisms of attentional control. PMID:27790082

Retro-dimension-cue benefit in visual working memory.

PubMed

Ye, Chaoxiong; Hu, Zhonghua; Ristaniemi, Tapani; Gendron, Maria; Liu, Qiang

2016-10-24

In visual working memory (VWM) tasks, participants' performance can be improved by a retro-object-cue. However, previous studies have not investigated whether participants' performance can also be improved by a retro-dimension-cue. Three experiments investigated this issue. We used a recall task with a retro-dimension-cue in all experiments. In Experiment 1, we found benefits from retro-dimension-cues compared to neutral cues. This retro-dimension-cue benefit is reflected in an increased probability of reporting the target, but not in the probability of reporting the non-target, as well as increased precision with which this item is remembered. Experiment 2 replicated the retro-dimension-cue benefit and showed that the length of the blank interval after the cue disappeared did not influence recall performance. Experiment 3 replicated the results of Experiment 2 with a lower memory load. Our studies provide evidence that there is a robust retro-dimension-cue benefit in VWM. Participants can use internal attention to flexibly allocate cognitive resources to a particular dimension of memory representations. The results also support the feature-based storing hypothesis.

Visual Search Elicits the Electrophysiological Marker of Visual Working Memory

PubMed Central

Emrich, Stephen M.; Al-Aidroos, Naseem; Pratt, Jay; Ferber, Susanne

2009-01-01

Background Although limited in capacity, visual working memory (VWM) plays an important role in many aspects of visually-guided behavior. Recent experiments have demonstrated an electrophysiological marker of VWM encoding and maintenance, the contralateral delay activity (CDA), which has been shown in multiple tasks that have both explicit and implicit memory demands. Here, we investigate whether the CDA is evident during visual search, a thoroughly-researched task that is a hallmark of visual attention but has no explicit memory requirements. Methodology/Principal Findings The results demonstrate that the CDA is present during a lateralized search task, and that it is similar in amplitude to the CDA observed in a change-detection task, but peaks slightly later. The changes in CDA amplitude during search were strongly correlated with VWM capacity, as well as with search efficiency. These results were paralleled by behavioral findings showing a strong correlation between VWM capacity and search efficiency. Conclusions/Significance We conclude that the activity observed during visual search was generated by the same neural resources that subserve VWM, and that this activity reflects the maintenance of previously searched distractors. PMID:19956663

Retro-dimension-cue benefit in visual working memory

PubMed Central

Ye, Chaoxiong; Hu, Zhonghua; Ristaniemi, Tapani; Gendron, Maria; Liu, Qiang

2016-01-01

In visual working memory (VWM) tasks, participants’ performance can be improved by a retro-object-cue. However, previous studies have not investigated whether participants’ performance can also be improved by a retro-dimension-cue. Three experiments investigated this issue. We used a recall task with a retro-dimension-cue in all experiments. In Experiment 1, we found benefits from retro-dimension-cues compared to neutral cues. This retro-dimension-cue benefit is reflected in an increased probability of reporting the target, but not in the probability of reporting the non-target, as well as increased precision with which this item is remembered. Experiment 2 replicated the retro-dimension-cue benefit and showed that the length of the blank interval after the cue disappeared did not influence recall performance. Experiment 3 replicated the results of Experiment 2 with a lower memory load. Our studies provide evidence that there is a robust retro-dimension-cue benefit in VWM. Participants can use internal attention to flexibly allocate cognitive resources to a particular dimension of memory representations. The results also support the feature-based storing hypothesis. PMID:27774983

The role of attention in binding visual features in working memory: evidence from cognitive ageing.

PubMed

Brown, Louise A; Brockmole, James R

2010-10-01

Two experiments were conducted to assess the costs of attentional load during a feature (colour-shape) binding task in younger and older adults. Experiment 1 showed that a demanding backwards counting task, which draws upon central executive/general attentional resources, reduced binding to a greater extent than individual feature memory, but the effect was no greater in older than in younger adults. Experiment 2 showed that presenting memory items sequentially rather than simultaneously, such that items are required to be maintained while new representations are created, selectively affects binding performance in both age groups. Although this experiment exhibited an age-related binding deficit overall, both age groups were affected by the attention manipulation to an equal extent. While a role for attentional processes in colour-shape binding was apparent across both experiments, manipulations of attention exerted equal effects in both age groups. We therefore conclude that age-related binding deficits neither emerge nor are exacerbated under conditions of high attentional load. Implications for theories of visual working memory and cognitive ageing are discussed.

Energy-aware Thread and Data Management in Heterogeneous Multi-core, Multi-memory Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Su, Chun-Yi

By 2004, microprocessor design focused on multicore scaling—increasing the number of cores per die in each generation—as the primary strategy for improving performance. These multicore processors typically equip multiple memory subsystems to improve data throughput. In addition, these systems employ heterogeneous processors such as GPUs and heterogeneous memories like non-volatile memory to improve performance, capacity, and energy efficiency. With the increasing volume of hardware resources and system complexity caused by heterogeneity, future systems will require intelligent ways to manage hardware resources. Early research to improve performance and energy efficiency on heterogeneous, multi-core, multi-memory systems focused on tuning a single primitivemore » or at best a few primitives in the systems. The key limitation of past efforts is their lack of a holistic approach to resource management that balances the tradeoff between performance and energy consumption. In addition, the shift from simple, homogeneous systems to these heterogeneous, multicore, multi-memory systems requires in-depth understanding of efficient resource management for scalable execution, including new models that capture the interchange between performance and energy, smarter resource management strategies, and novel low-level performance/energy tuning primitives and runtime systems. Tuning an application to control available resources efficiently has become a daunting challenge; managing resources in automation is still a dark art since the tradeoffs among programming, energy, and performance remain insufficiently understood. In this dissertation, I have developed theories, models, and resource management techniques to enable energy-efficient execution of parallel applications through thread and data management in these heterogeneous multi-core, multi-memory systems. I study the effect of dynamic concurrent throttling on the performance and energy of multi-core, non-uniform memory access (NUMA) systems. I use critical path analysis to quantify memory contention in the NUMA memory system and determine thread mappings. In addition, I implement a runtime system that combines concurrent throttling and a novel thread mapping algorithm to manage thread resources and improve energy efficient execution in multi-core, NUMA systems.« less

Lie construction affects information storage under high memory load condition.

PubMed

Liu, Yuqiu; Wang, Chunjie; Jiang, Haibo; He, Hongjian; Chen, Feiyan

2017-01-01

Previous studies indicate that lying consumes cognitive resources, especially working memory (WM) resources. Considering the dual functions that WM might play in lying: holding the truth-related information and turning the truth into lies, the present study examined the relationship between the information storage and processing in the lie construction. To achieve that goal, a deception task based on the old/new recognition paradigm was designed, which could manipulate two levels of WM load (low-load task using 4 items and high-load task using 6 items) during the deception process. The analyses based on the amplitude of the contralateral delay activity (CDA), a proved index of the number of representations being held in WM, showed that the CDA amplitude was lower in the deception process than that in the truth telling process under the high-load condition. In contrast, under the low-load condition, no CDA difference was found between the deception and truth telling processes. Therefore, we deduced that the lie construction and information storage compete for WM resources; when the available WM resources cannot meet this cognitive demand, the WM resources occupied by the information storage would be consumed by the lie construction.

Lie construction affects information storage under high memory load condition

PubMed Central

Liu, Yuqiu; Wang, Chunjie; Jiang, Haibo; He, Hongjian; Chen, Feiyan

2017-01-01

Previous studies indicate that lying consumes cognitive resources, especially working memory (WM) resources. Considering the dual functions that WM might play in lying: holding the truth-related information and turning the truth into lies, the present study examined the relationship between the information storage and processing in the lie construction. To achieve that goal, a deception task based on the old/new recognition paradigm was designed, which could manipulate two levels of WM load (low-load task using 4 items and high-load task using 6 items) during the deception process. The analyses based on the amplitude of the contralateral delay activity (CDA), a proved index of the number of representations being held in WM, showed that the CDA amplitude was lower in the deception process than that in the truth telling process under the high-load condition. In contrast, under the low-load condition, no CDA difference was found between the deception and truth telling processes. Therefore, we deduced that the lie construction and information storage compete for WM resources; when the available WM resources cannot meet this cognitive demand, the WM resources occupied by the information storage would be consumed by the lie construction. PMID:28727794

A Little Goes a Long Way: Low Working Memory Load Is Associated with Optimal Distractor Inhibition and Increased Vagal Control under Anxiety.

PubMed

Spangler, Derek P; Friedman, Bruce H

2017-01-01

Anxiety impairs both inhibition of distraction and attentional focus. It is unclear whether these impairments are reduced or exacerbated when loading working memory with non-affective information. Cardiac vagal control has been related to top-down regulation of anxiety; therefore, vagal control may reflect load-related inhibition of distraction under anxiety. The present study examined whether: (1) the enhancing and impairing effects of load on inhibition exist together in a non-linear function, (2) there is a similar association between inhibition and concurrent vagal control under anxiety. During anxiogenic threat-of-noise, 116 subjects maintained a digit series of varying lengths (0, 2, 4, and 6 digits) while completing a visual flanker task. The task was broken into four blocks, with a baseline period preceding each. Electrocardiography was acquired throughout to quantify vagal control as high-frequency heart rate variability (HRV). There were significant quadratic relations of working memory load to flanker performance and to HRV, but no associations between HRV and performance. Results indicate that low load was associated with relatively better inhibition and increased HRV. These findings suggest that attentional performance under anxiety depends on the availability of working memory resources, which might be reflected by vagal control. These results have implications for treating anxiety disorders, in which regulation of anxiety can be optimized for attentional focus.

Facial expression perception correlates with verbal working memory function in schizophrenia.

PubMed

Hagiya, Kumiko; Sumiyoshi, Tomiki; Kanie, Ayako; Pu, Shenghong; Kaneko, Koichi; Mogami, Tamiko; Oshima, Sachie; Niwa, Shin-ichi; Inagaki, Akiko; Ikebuchi, Emi; Kikuchi, Akiko; Yamasaki, Syudo; Iwata, Kazuhiko; Nakagome, Kazuyuki

2015-12-01

Facial emotion perception is considered to provide a measure of social cognition. Numerous studies have examined the perception of emotion in patients with schizophrenia, and the majority has reported impaired ability to recognize facial emotion perception. We aimed to investigate the correlation between facial expression recognition and other domains of social cognition and neurocognition in Japanese patients with schizophrenia. Participants were 52 patients with schizophrenia and 53 normal controls with no history of psychiatric diseases. All participants completed the Hinting Task and the Social Cognition Screening Questionnaire. The Brief Assessment of Cognition in Schizophrenia was administered only to the patients. Facial emotion perception measured by the Facial Emotion Selection Test (FEST) was compared between the patients and normal controls. Patients performed significantly worse on the FEST compared to normal control subjects. The FEST total score was significantly positively correlated with scores of the Brief Assessment of Cognition in Schizophrenia attention subscale, Hinting Task, Social Cognition Screening Questionnaire Verbal Working Memory and Metacognition subscales. Stepwise multiple regression analysis revealed that verbal working memory function was positively related to the facial emotion perception ability in patients with schizophrenia. These results point to the concept that facial emotion perception and some types of working memory use common cognitive resources. Our findings may provide implications for cognitive rehabilitation and related interventions in schizophrenia. © 2015 The Authors. Psychiatry and Clinical Neurosciences © 2015 Japanese Society of Psychiatry and Neurology.

Opposing effects of perceptual versus working memory load on emotional distraction.

PubMed

Tavares, Tamara P; Logie, Kyle; Mitchell, Derek G V

2016-10-01

Throughout our day-to-day activities, we are subjected to numerous stimuli that compete for our attention; consequently, we must prioritize stimuli for further processing and influence over behaviour. Previous research has demonstrated that the extent to which task-irrelevant distractors are processed is mediated by the nature of the cognitive task, and the level of processing load. Importantly though, the interaction between cognitive task, processing load, and emotional distractor processing remains unclear. This is a particularly important question given the unique ways that emotion interacts with attention, and the fact that some other forms of processing load have been shown to reduce emotional distractor encoding. In the present study, participants were presented with emotional distractors during a perceptual and working memory task, under varying levels of load. In Experiment 1, we showed that the impact of emotional distractors on behaviour was reduced under conditions of high relative to low perceptual load. However, in sharp contrast, high working memory load was associated with increased emotional distraction. Importantly, these results were replicated in Experiment 2. Overall, the impact of processing load on emotional distraction varies according to the cognitive function being performed. These results raise the intriguing possibility that working memory operations deplete some of the cognitive resources needed to control the impact of emotion on behaviour. The findings, therefore, may have important implications for clinical populations featuring cognitive dysfunction and emotional dysregulation.

A Little Goes a Long Way: Low Working Memory Load Is Associated with Optimal Distractor Inhibition and Increased Vagal Control under Anxiety

PubMed Central

Spangler, Derek P.; Friedman, Bruce H.

2017-01-01

Anxiety impairs both inhibition of distraction and attentional focus. It is unclear whether these impairments are reduced or exacerbated when loading working memory with non-affective information. Cardiac vagal control has been related to top–down regulation of anxiety; therefore, vagal control may reflect load-related inhibition of distraction under anxiety. The present study examined whether: (1) the enhancing and impairing effects of load on inhibition exist together in a non-linear function, (2) there is a similar association between inhibition and concurrent vagal control under anxiety. During anxiogenic threat-of-noise, 116 subjects maintained a digit series of varying lengths (0, 2, 4, and 6 digits) while completing a visual flanker task. The task was broken into four blocks, with a baseline period preceding each. Electrocardiography was acquired throughout to quantify vagal control as high-frequency heart rate variability (HRV). There were significant quadratic relations of working memory load to flanker performance and to HRV, but no associations between HRV and performance. Results indicate that low load was associated with relatively better inhibition and increased HRV. These findings suggest that attentional performance under anxiety depends on the availability of working memory resources, which might be reflected by vagal control. These results have implications for treating anxiety disorders, in which regulation of anxiety can be optimized for attentional focus. PMID:28217091

The role of processing difficulty in the predictive utility of working memory span.

PubMed

Bunting, Michael

2006-12-01

Storage-plus-processing working memory span tasks (e.g., operation span [OSPAN]) are strong predictors of higher order cognition, including general fluid intelligence. This is due, in part, to the difficulty of the processing component. When the processing component prevents only articulatory rehearsal, but not executive attentional control, the predictive utility is attenuated. Participants in one experiment (N = 59) completed Raven's Advanced Progressive Matrices (RAPM) and multiple versions of OSPAN and probed recall (PR). A distractor task (high or low difficulty) was added to PR, and OSPAN's processing component was manipulated for difficulty. OSPAN and PR correlated with RAPM when the processing component took executive attentional control. These results are suggestive of resource sharing between processing and storage.

Prospective memory across adolescence: the effects of age and cue focality.

PubMed

Wang, Lijuan; Altgassen, Mareike; Liu, Wei; Xiong, Weirui; Akgün, Canan; Kliegel, Matthias

2011-01-01

The present study examined the role of controlled attention in age differences in event-based prospective memory performance across adolescence. The researchers tested whether presenting the prospective memory cue in or out of focal awareness of the ongoing task (resulting in low versus high demands for controlled attention, respectively) might affect age-related prospective memory performance. In total, 119 Chinese participants ages 13 to 20 took part in this study (60 adolescents: age M = 13.26 years, SD = 0.50; 23 boys; 59 young adults: age M = 19.70 years, SD = 0.87; 19 men). Findings demonstrated a significant interaction, F(1, 114) = 6.41, p < .05. No effect of age on prospective memory performance was revealed when a focal cue was used (F < 1), whereas there was a reliable age effect between adolescents and young adults when nonfocal prospective memory cues were presented, F(1, 59) = 16.13, p < .01. This pattern of results suggests that the interplay of both available resources of controlled attention and working memory, along with specific task demands, may contribute to possible age differences in prospective memory performance across adolescence. Results are discussed in the context of the multiprocess theory of prospective memory.

A multidisciplinary approach of workload assessment in real-job situations: investigation in the field of aerospace activities.

PubMed

Mélan, Claudine; Cascino, Nadine

2014-01-01

The present contribution presents two field studies combining tools and methods from cognitive psychology and from occupational psychology in order to perform a thorough investigation of workload in employees. Cognitive load theory proposes to distinguish different load categories of working memory, in a context of instruction. Intrinsic load is inherent to the task, extraneous load refers to components of a learning environment that may be modified to reduce total load, and germane load enables schemas construction and thus efficient learning. We showed previously that this theoretical framework may be successfully extended to working memory tasks in non-instructional designs. Other theoretical models, issued from the field of occupational psychology, account for an individual's perception of work demands or requirements in the context of different psychosocial features of the (work) environment. Combining these approaches is difficult as workload assessment by job-perception questionnaires explore an individual's overall job-perception over a large time-period, whereas cognitive load investigations in working memory tasks are typically performed within short time-periods. We proposed an original methodology enabling investigation of workload and load factors in a comparable time-frame. We report two field studies investigating workload on different shift-phases and between work-shifts, with two custom-made tools. The first one enabled workload assessment by manipulating intrinsic load (task difficulty) and extraneous load (time pressure) in a working-memory task. The second tool was a questionnaire based on the theoretical concepts of work-demands, control, and psychosocial support. Two additional dimensions suspected to contribute to job-perception, i.e., work-family conflicts and availability of human and technical resources were also explored. Results of workload assessments were discussed in light of operators' alertness and job-performance.

Eye movements reduce vividness and emotionality of "flashforwards".

PubMed

Engelhard, Iris M; van den Hout, Marcel A; Janssen, Wilco C; van der Beek, Jorinde

2010-05-01

Earlier studies have shown that eye movements during retrieval of disturbing images about past events reduce their vividness and emotionality, which may be due to both tasks competing for working memory resources. This study examined whether eye movements reduce vividness and emotionality of visual distressing images about feared future events: "flashforwards". A non-clinical sample was asked to select two images of feared future events, which were self-rated for vividness and emotionality. These images were retrieved while making eye movements or without a concurrent secondary task, and then vividness and emotionality were rated again. Relative to the no-dual task condition, eye movements while thinking of future-oriented images resulted in decreased ratings of image vividness and emotional intensity. Apparently, eye movements reduce vividness and emotionality of visual images about past and future feared events. This is in line with a working memory account of the beneficial effects of eye movements, which predicts that any task that taxes working memory during retrieval of disturbing mental images will be beneficial. Copyright 2010 Elsevier Ltd. All rights reserved.

Inhibition-Induced Forgetting Results from Resource Competition between Response Inhibition and Memory Encoding Processes.

PubMed

Chiu, Yu-Chin; Egner, Tobias

2015-08-26

Response inhibition is a key component of executive control, but its relation to other cognitive processes is not well understood. We recently documented the "inhibition-induced forgetting effect": no-go cues are remembered more poorly than go cues. We attributed this effect to central-resource competition, whereby response inhibition saps attention away from memory encoding. However, this proposal is difficult to test with behavioral means alone. We therefore used fMRI in humans to test two neural predictions of the "common resource hypothesis": (1) brain regions associated with response inhibition should exhibit greater resource demands during encoding of subsequently forgotten than remembered no-go cues; and (2) this higher inhibitory resource demand should lead to memory encoding regions having less resources available during encoding of subsequently forgotten no-go cues. Participants categorized face stimuli by gender in a go/no-go task and, following a delay, performed a surprise recognition memory test for those faces. Replicating previous findings, memory was worse for no-go than for go stimuli. Crucially, forgetting of no-go cues was predicted by high inhibitory resource demand, as quantified by the trial-by-trial ratio of activity in neural "no-go" versus "go" networks. Moreover, this index of inhibitory demand exhibited an inverse trial-by-trial relationship with activity in brain regions responsible for the encoding of no-go cues into memory, notably the ventrolateral prefrontal cortex. This seesaw pattern between the neural resource demand of response inhibition and activity related to memory encoding directly supports the hypothesis that response inhibition temporarily saps attentional resources away from stimulus processing. Recent behavioral experiments showed that inhibiting a motor response to a stimulus (a "no-go cue") impairs subsequent memory for that cue. Here, we used fMRI to test whether this "inhibition-induced forgetting effect" is caused by competition for neural resources between the processes of response inhibition and memory encoding. We found that trial-by-trial variations in neural inhibitory resource demand predicted subsequent forgetting of no-go cues and that higher inhibitory demand was furthermore associated with lower concurrent activation in brain regions responsible for successful memory encoding of no-go cues. Thus, motor inhibition and stimulus encoding appear to compete with each other: when more resources have to be devoted to inhibiting action, less are available for encoding sensory stimuli. Copyright © 2015 the authors 0270-6474/15/3511936-10$15.00/0.

Low latency memory access and synchronization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blumrich, Matthias A.; Chen, Dong; Coteus, Paul W.

A low latency memory system access is provided in association with a weakly-ordered multiprocessor system. Each processor in the multiprocessor shares resources, and each shared resource has an associated lock within a locking device that provides support for synchronization between the multiple processors in the multiprocessor and the orderly sharing of the resources. A processor only has permission to access a resource when it owns the lock associated with that resource, and an attempt by a processor to own a lock requires only a single load operation, rather than a traditional atomic load followed by store, such that the processormore » only performs a read operation and the hardware locking device performs a subsequent write operation rather than the processor. A simple prefetching for non-contiguous data structures is also disclosed. A memory line is redefined so that in addition to the normal physical memory data, every line includes a pointer that is large enough to point to any other line in the memory, wherein the pointers to determine which memory line to prefetch rather than some other predictive algorithm. This enables hardware to effectively prefetch memory access patterns that are non-contiguous, but repetitive.« less

Low latency memory access and synchronization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blumrich, Matthias A.; Chen, Dong; Coteus, Paul W.

A low latency memory system access is provided in association with a weakly-ordered multiprocessor system. Bach processor in the multiprocessor shares resources, and each shared resource has an associated lock within a locking device that provides support for synchronization between the multiple processors in the multiprocessor and the orderly sharing of the resources. A processor only has permission to access a resource when it owns the lock associated with that resource, and an attempt by a processor to own a lock requires only a single load operation, rather than a traditional atomic load followed by store, such that the processormore » only performs a read operation and the hardware locking device performs a subsequent write operation rather than the processor. A simple prefetching for non-contiguous data structures is also disclosed. A memory line is redefined so that in addition to the normal physical memory data, every line includes a pointer that is large enough to point to any other line in the memory, wherein the pointers to determine which memory line to prefetch rather than some other predictive algorithm. This enables hardware to effectively prefetch memory access patterns that are non-contiguous, but repetitive.« less

Synaptic efficacy shapes resource limitations in working memory.

PubMed

Krishnan, Nikhil; Poll, Daniel B; Kilpatrick, Zachary P

2018-06-01

Working memory (WM) is limited in its temporal length and capacity. Classic conceptions of WM capacity assume the system possesses a finite number of slots, but recent evidence suggests WM may be a continuous resource. Resource models typically assume there is no hard upper bound on the number of items that can be stored, but WM fidelity decreases with the number of items. We analyze a neural field model of multi-item WM that associates each item with the location of a bump in a finite spatial domain, considering items that span a one-dimensional continuous feature space. Our analysis relates the neural architecture of the network to accumulated errors and capacity limitations arising during the delay period of a multi-item WM task. Networks with stronger synapses support wider bumps that interact more, whereas networks with weaker synapses support narrower bumps that are more susceptible to noise perturbations. There is an optimal synaptic strength that both limits bump interaction events and the effects of noise perturbations. This optimum shifts to weaker synapses as the number of items stored in the network is increased. Our model not only provides a circuit-based explanation for WM capacity, but also speaks to how capacity relates to the arrangement of stored items in a feature space.

Parietal plasticity after training with a complex video game is associated with individual differences in improvements in an untrained working memory task

PubMed Central

Nikolaidis, Aki; Voss, Michelle W.; Lee, Hyunkyu; Vo, Loan T. K.; Kramer, Arthur F.

2014-01-01

Researchers have devoted considerable attention and resources to cognitive training, yet there have been few examinations of the relationship between individual differences in patterns of brain activity during the training task and training benefits on untrained tasks (i.e., transfer). While a predominant hypothesis suggests that training will transfer if there is training-induced plasticity in brain regions important for the untrained task, this theory lacks sufficient empirical support. To address this issue we investigated the relationship between individual differences in training-induced changes in brain activity during a cognitive training videogame, and whether those changes explained individual differences in the resulting changes in performance in untrained tasks. Forty-five young adults trained with a videogame that challenges working memory, attention, and motor control for 15 2-h sessions. Before and after training, all subjects received neuropsychological assessments targeting working memory, attention, and procedural learning to assess transfer. Subjects also underwent pre- and post-functional magnetic resonance imaging (fMRI) scans while they played the training videogame to assess how these patterns of brain activity change in response to training. For regions implicated in working memory, such as the superior parietal lobe (SPL), individual differences in the post-minus-pre changes in activation predicted performance changes in an untrained working memory task. These findings suggest that training-induced plasticity in the functional representation of a training task may play a role in individual differences in transfer. Our data support and extend previous literature that has examined the association between training related cognitive changes and associated changes in underlying neural networks. We discuss the role of individual differences in brain function in training generalizability and make suggestions for future cognitive training research. PMID:24711792

Parietal plasticity after training with a complex video game is associated with individual differences in improvements in an untrained working memory task.

PubMed

Nikolaidis, Aki; Voss, Michelle W; Lee, Hyunkyu; Vo, Loan T K; Kramer, Arthur F

2014-01-01

Researchers have devoted considerable attention and resources to cognitive training, yet there have been few examinations of the relationship between individual differences in patterns of brain activity during the training task and training benefits on untrained tasks (i.e., transfer). While a predominant hypothesis suggests that training will transfer if there is training-induced plasticity in brain regions important for the untrained task, this theory lacks sufficient empirical support. To address this issue we investigated the relationship between individual differences in training-induced changes in brain activity during a cognitive training videogame, and whether those changes explained individual differences in the resulting changes in performance in untrained tasks. Forty-five young adults trained with a videogame that challenges working memory, attention, and motor control for 15 2-h sessions. Before and after training, all subjects received neuropsychological assessments targeting working memory, attention, and procedural learning to assess transfer. Subjects also underwent pre- and post-functional magnetic resonance imaging (fMRI) scans while they played the training videogame to assess how these patterns of brain activity change in response to training. For regions implicated in working memory, such as the superior parietal lobe (SPL), individual differences in the post-minus-pre changes in activation predicted performance changes in an untrained working memory task. These findings suggest that training-induced plasticity in the functional representation of a training task may play a role in individual differences in transfer. Our data support and extend previous literature that has examined the association between training related cognitive changes and associated changes in underlying neural networks. We discuss the role of individual differences in brain function in training generalizability and make suggestions for future cognitive training research.

How Verbal and Spatial Manipulation Networks Contribute to Calculation: An fMRI Study

ERIC Educational Resources Information Center

Zago, Laure; Petit, Laurent; Turbelin, Marie-Renee; Andersson, Frederic; Vigneau, Mathieu; Tzourio-Mazoyer, Nathalie

2008-01-01

The manipulation of numbers required during calculation is known to rely on working memory (WM) resources. Here, we investigated the respective contributions of verbal and/or spatial WM manipulation brain networks during the addition of four numbers performed by adults, using functional magnetic resonance imaging (fMRI). Both manipulation and…

Human Abilities and Modes of Attention: The Issue of Stylistic Consistencies in Cognition.

ERIC Educational Resources Information Center

Messick, Samuel

Spearman's notions of mental energy and mental span presage modern conceptions of attentional resources and working memory as fundamental to intelligence. Viewing attention as the conative directing of the intellect, as "the application of intellectual energy," Spearman's quantitative law of mental span deals with limits on the…

A multidisciplinary approach of workload assessment in real-job situations: investigation in the field of aerospace activities

PubMed Central

Mélan, Claudine; Cascino, Nadine

2014-01-01

The present contribution presents two field studies combining tools and methods from cognitive psychology and from occupational psychology in order to perform a thorough investigation of workload in employees. Cognitive load theory proposes to distinguish different load categories of working memory, in a context of instruction. Intrinsic load is inherent to the task, extraneous load refers to components of a learning environment that may be modified to reduce total load, and germane load enables schemas construction and thus efficient learning. We showed previously that this theoretical framework may be successfully extended to working memory tasks in non-instructional designs. Other theoretical models, issued from the field of occupational psychology, account for an individual’s perception of work demands or requirements in the context of different psychosocial features of the (work) environment. Combining these approaches is difficult as workload assessment by job-perception questionnaires explore an individual’s overall job-perception over a large time-period, whereas cognitive load investigations in working memory tasks are typically performed within short time-periods. We proposed an original methodology enabling investigation of workload and load factors in a comparable time-frame. We report two field studies investigating workload on different shift-phases and between work-shifts, with two custom-made tools. The first one enabled workload assessment by manipulating intrinsic load (task difficulty) and extraneous load (time pressure) in a working-memory task. The second tool was a questionnaire based on the theoretical concepts of work-demands, control, and psychosocial support. Two additional dimensions suspected to contribute to job-perception, i.e., work–family conflicts and availability of human and technical resources were also explored. Results of workload assessments were discussed in light of operators’ alertness and job-performance. PMID:25232346

A malicious pattern detection engine for embedded security systems in the Internet of Things.

PubMed

Oh, Doohwan; Kim, Deokho; Ro, Won Woo

2014-12-16

With the emergence of the Internet of Things (IoT), a large number of physical objects in daily life have been aggressively connected to the Internet. As the number of objects connected to networks increases, the security systems face a critical challenge due to the global connectivity and accessibility of the IoT. However, it is difficult to adapt traditional security systems to the objects in the IoT, because of their limited computing power and memory size. In light of this, we present a lightweight security system that uses a novel malicious pattern-matching engine. We limit the memory usage of the proposed system in order to make it work on resource-constrained devices. To mitigate performance degradation due to limitations of computation power and memory, we propose two novel techniques, auxiliary shifting and early decision. Through both techniques, we can efficiently reduce the number of matching operations on resource-constrained systems. Experiments and performance analyses show that our proposed system achieves a maximum speedup of 2.14 with an IoT object and provides scalable performance for a large number of patterns.

Executive control of stimulus-driven and goal-directed attention in visual working memory.

PubMed

Hu, Yanmei; Allen, Richard J; Baddeley, Alan D; Hitch, Graham J

2016-10-01

We examined the role of executive control in stimulus-driven and goal-directed attention in visual working memory using probed recall of a series of objects, a task that allows study of the dynamics of storage through analysis of serial position data. Experiment 1 examined whether executive control underlies goal-directed prioritization of certain items within the sequence. Instructing participants to prioritize either the first or final item resulted in improved recall for these items, and an increase in concurrent task difficulty reduced or abolished these gains, consistent with their dependence on executive control. Experiment 2 examined whether executive control is also involved in the disruption caused by a post-series visual distractor (suffix). A demanding concurrent task disrupted memory for all items except the most recent, whereas a suffix disrupted only the most recent items. There was no interaction when concurrent load and suffix were combined, suggesting that deploying selective attention to ignore the distractor did not draw upon executive resources. A final experiment replicated the independent interfering effects of suffix and concurrent load while ruling out possible artifacts. We discuss the results in terms of a domain-general episodic buffer in which information is retained in a transient, limited capacity privileged state, influenced by both stimulus-driven and goal-directed processes. The privileged state contains the most recent environmental input together with goal-relevant representations being actively maintained using executive resources.

Neuronal Oscillations Indicate Sleep-dependent Changes in the Cortical Memory Trace.

PubMed

Köster, Moritz; Finger, Holger; Kater, Maren-Jo; Schenk, Christoph; Gruber, Thomas

2017-04-01

Sleep promotes the consolidation of newly acquired associative memories. Here we used neuronal oscillations in the human EEG to investigate sleep-dependent changes in the cortical memory trace. The retrieval activity for object-color associations was assessed immediately after encoding and after 3 hr of sleep or wakefulness. Sleep had beneficial effects on memory performance and led to reduced event-related theta and gamma power during the retrieval of associative memories. Furthermore, event-related alpha suppression was attenuated in the wake group for memorized and novel stimuli. There were no sleep-dependent changes in retrieval activity for missed items or items retrieved without color. Thus, the sleep-dependent reduction in theta and gamma oscillations was specific for the retrieval of associative memories. In line with theoretical accounts on sleep-dependent memory consolidation, decreased theta may indicate reduced mediotemporal activity because of a transfer of information into neocortical networks during sleep, whereas reduced parietal gamma may reflect effects of synaptic downscaling. Changes in alpha suppression in the wake group possibly index reduced attentional resources that may also contribute to a lower memory performance in this group. These findings indicate that the consolidation of associative memories during sleep is associated with profound changes in the cortical memory trace and relies on multiple neuronal processes working in concert.

The effect of strategic memory training in older adults: who benefits most?

PubMed

Rosi, Alessia; Del Signore, Federica; Canelli, Elisa; Allegri, Nicola; Bottiroli, Sara; Vecchi, Tomaso; Cavallini, Elena

2017-12-07

Previous research has suggested that there is a degree of variability among older adults' response to memory training, such that some individuals benefit more than others. The aim of the present study was to identify the profile of older adults who were likely to benefit most from a strategic memory training program that has previously proved to be effective in improving memory in healthy older adults. In total, 44 older adults (60-83 years) participated in a strategic memory training. We examined memory training benefits by measuring changes in memory practiced (word list learning) and non-practiced tasks (grocery list and associative learning). In addition, a battery of cognitive measures was administered in order to assess crystallized and fluid abilities, short-term memory, working memory, and processing speed. Results confirmed the efficacy of the training in improving performance in both practiced and non-practiced memory tasks. For the practiced memory tasks, results showed that memory baseline performance and crystallized ability predicted training gains. For the non-practiced memory tasks, analyses showed that memory baseline performance was a significant predictor of gain in the grocery list learning task. For the associative learning task, the significant predictors were memory baseline performance, processing speed, and marginally the age. Our results indicate that older adults with a higher baseline memory capacity and with more efficient cognitive resources were those who tended to benefit most from the training. The present study provides new avenues in designing personalized intervention according to the older adults' cognitive profile.

The Effect of Divided Attention on Emotion-Induced Memory Narrowing

PubMed Central

Steinmetz, Katherine R. Mickley; Waring, Jill D.; Kensinger, Elizabeth A.

2014-01-01

Individuals are more likely to remember emotional than neutral information, but this benefit does not always extend to the surrounding background information. This memory narrowing is theorized to be linked to the availability of attentional resources at encoding. In contrast to the predictions of this theoretical account, altering participants’ attentional resources at encoding, by dividing attention, did not affect the emotion-induced memory narrowing. Attention was divided using three separate manipulations: a digit ordering task (Experiment 1), an arithmetic task (Experiment 2), and an auditory discrimination task (Experiment 3). Across all three experiments, divided attention decreased memory across-the-board but did not affect the degree of memory narrowing. These findings suggest that theories to explain memory narrowing must be expanded to include other potential mechanisms beyond limitations of attentional resources. PMID:24295041

The effect of divided attention on emotion-induced memory narrowing.

PubMed

Mickley Steinmetz, Katherine R; Waring, Jill D; Kensinger, Elizabeth A

2014-01-01

Individuals are more likely to remember emotional than neutral information, but this benefit does not always extend to the surrounding background information. This memory narrowing is theorised to be linked to the availability of attentional resources at encoding. In contrast to the predictions of this theoretical account, altering participants' attentional resources at encoding by dividing attention did not affect emotion-induced memory narrowing. Attention was divided using three separate manipulations: a digit ordering task (Experiment 1), an arithmetic task (Experiment 2) and an auditory discrimination task (Experiment 3). Across all three experiments, divided attention decreased memory across the board but did not affect the degree of memory narrowing. These findings suggest that theories to explain memory narrowing must be expanded to include other potential mechanisms beyond the limitations of attentional resources.

Fine-grained, local maps and coarse, global representations support human spatial working memory.

PubMed

Katshu, Mohammad Zia Ul Haq; d'Avossa, Giovanni

2014-01-01

While sensory processes are tuned to particular features, such as an object's specific location, color or orientation, visual working memory (vWM) is assumed to store information using representations, which generalize over a feature dimension. Additionally, current vWM models presume that different features or objects are stored independently. On the other hand, configurational effects, when observed, are supposed to mainly reflect encoding strategies. We show that the location of the target, relative to the display center and boundaries, and overall memory load influenced recall precision, indicating that, like sensory processes, capacity limited vWM resources are spatially tuned. When recalling one of three memory items the target distance from the display center was overestimated, similar to the error when only one item was memorized, but its distance from the memory items' average position was underestimated, showing that not only individual memory items' position, but also the global configuration of the memory array may be stored. Finally, presenting the non-target items at recall, consequently providing landmarks and configurational information, improved precision and accuracy of target recall. Similarly, when the non-target items were translated at recall, relative to their position in the initial display, a parallel displacement of the recalled target was observed. These findings suggest that fine-grained spatial information in vWM is represented in local maps whose resolution varies with distance from landmarks, such as the display center, while coarse representations are used to store the memory array configuration. Both these representations are updated at the time of recall.

Fine-Grained, Local Maps and Coarse, Global Representations Support Human Spatial Working Memory

PubMed Central

Katshu, Mohammad Zia Ul Haq; d'Avossa, Giovanni

2014-01-01

While sensory processes are tuned to particular features, such as an object's specific location, color or orientation, visual working memory (vWM) is assumed to store information using representations, which generalize over a feature dimension. Additionally, current vWM models presume that different features or objects are stored independently. On the other hand, configurational effects, when observed, are supposed to mainly reflect encoding strategies. We show that the location of the target, relative to the display center and boundaries, and overall memory load influenced recall precision, indicating that, like sensory processes, capacity limited vWM resources are spatially tuned. When recalling one of three memory items the target distance from the display center was overestimated, similar to the error when only one item was memorized, but its distance from the memory items' average position was underestimated, showing that not only individual memory items' position, but also the global configuration of the memory array may be stored. Finally, presenting the non-target items at recall, consequently providing landmarks and configurational information, improved precision and accuracy of target recall. Similarly, when the non-target items were translated at recall, relative to their position in the initial display, a parallel displacement of the recalled target was observed. These findings suggest that fine-grained spatial information in vWM is represented in local maps whose resolution varies with distance from landmarks, such as the display center, while coarse representations are used to store the memory array configuration. Both these representations are updated at the time of recall. PMID:25259601

The neural fate of neutral information in emotion-enhanced memory.

PubMed

Watts, Sarah; Buratto, Luciano G; Brotherhood, Emilie V; Barnacle, Gemma E; Schaefer, Alexandre

2014-07-01

In this study, we report evidence that neural activity reflecting the encoding of emotionally neutral information in memory is reduced when neutral and emotional stimuli are intermixed during encoding. Specifically, participants studied emotional and neutral pictures organized in mixed lists (in which emotional and neutral pictures were intermixed) or in pure lists (only-neutral or only-emotional pictures) and performed a recall test. To estimate encoding efficiency, we used the Dm effect, measured with event-related potentials. Recall for neutral items was lower in mixed compared to pure lists and posterior Dm activity for neutral items was reduced in mixed lists, whereas it remained robust in pure lists. These findings might be caused by an asymmetrical competition for attentional and working memory resources between emotional and neutral information, which could be a major determinant of emotional memory effects. Copyright © 2014 Society for Psychophysiological Research.

Individual differences in working memory and reasoning-remembering relationships in solving class-inclusion problems.

PubMed

Howe, M L; Rabinowitz, F M; Powell, T L

1998-09-01

In the present experiment, we evaluated the effects of individual differences in reading span and variation in memory demands on class-inclusion performance. One hundred twenty college students whose reading spans ranged from low to medium to high (as indexed by a computerized version of the Daneman and Carpenter [1980] reading-span task) solved 48 class-inclusion problems. Half of the subjects had the solution information available when the problems were presented; the other half performed a detection task between solution information and problem presentation. The results from both standard statistical analyses and from a mathematical model indicated that differences in reading span and memory load had predictable, similar effects. Specifically, the sophistication of reasoning strategies declined when memory demands increased or when reading spans decreased. Surprisingly, these effects were primarily additive. The results were interpreted in terms of global resource models and findings from the developmental literature.

Mindful maths: reducing the impact of stereotype threat through a mindfulness exercise.

PubMed

Weger, Ulrich W; Hooper, Nic; Meier, Brian P; Hopthrow, Tim

2012-03-01

Individuals who experience stereotype threat - the pressure resulting from social comparisons that are perceived as unfavourable - show performance decrements across a wide range of tasks. One account of this effect is that the cognitive pressure triggered by such threat drains the same cognitive (or working-memory) resources that are implicated in the respective task. The present study investigates whether mindfulness can be used to moderate stereotype threat, as mindfulness has previously been shown to alleviate working-memory load. Our results show that performance decrements that typically occur under stereotype threat can indeed be reversed when the individual engages in a brief (5 min) mindfulness task. The theoretical implications of our findings are discussed. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.

Preservation of musical memory and engagement in healthy aging and Alzheimer's disease.

PubMed

Cuddy, Lola L; Sikka, Ritu; Vanstone, Ashley

2015-03-01

In striking contrast to the difficulties with new learning and episodic memories in aging and especially in Alzheimer's disease (AD), musical long-term memories appear to be largely preserved. Evidence for spared musical memories in aging and AD is reviewed here. New data involve the development of a Musical Engagement Questionnaire especially designed for use with AD patients. The questionnaire assesses behavioral responses to music and is answered by the care partner. Current results show that, despite cognitive loss, persons with mild to moderate AD preserve musical engagement and music seeking. Familiar music evokes personal autobiographical memories for healthy younger and older adults as well and for those with mild to moderate AD. It is argued that music is a prime candidate for being a stimulus for cognitive stimulation because musical memories and associated emotions may be readily evoked; that is, they are strong and do not need to be repaired. Working with and through music as a resource may enhance social and communication functions. © 2015 New York Academy of Sciences.

Blurring emotional memories using eye movements: individual differences and speed of eye movements.

PubMed

van Schie, Kevin; van Veen, Suzanne C; Engelhard, Iris M; Klugkist, Irene; van den Hout, Marcel A

2016-01-01

In eye movement desensitization and reprocessing (EMDR), patients make eye movements (EM) while recalling traumatic memories. Making EM taxes working memory (WM), which leaves less resources available for imagery of the memory. This reduces memory vividness and emotionality during future recalls. WM theory predicts that individuals with small working memory capacities (WMCs) benefit more from low levels of taxing (i.e., slow EM) whereas individuals with large WMC benefit more from high levels of taxing (i.e., fast EM). We experimentally examined and tested four prespecified hypotheses regarding the role of WMC and EM speed in reducing emotionality and vividness ratings: 1) EM-regardless of WMC and EM speed-are more effective compared to no dual task, 2) increasing EM speed only affects the decrease in memory ratings irrespective of WMC, 3) low-WMC individuals-compared to high-WMC individuals-benefit more from making either type of EM, 4) the EM intervention is most effective when-as predicted by WM theory-EM are adjusted to WMC. Undergraduates with low (n=31) or high (n=35) WMC recalled three emotional memories and rated vividness and emotionality before and after each condition (recall only, recall + slow EM, and recall + fast EM). Contrary to the theory, the data do not support the hypothesis that EM speed should be adjusted to WMC (hypothesis 4). However, the data show that a dual task in general is more effective in reducing memory ratings than no dual task (hypothesis 1), and that a more cognitively demanding dual task increases the intervention's effectiveness (hypothesis 2). Although adjusting EM speed to an individual's WMC seems a straightforward clinical implication, the data do not show any indication that such a titration is helpful.

Blurring emotional memories using eye movements: individual differences and speed of eye movements

PubMed Central

van Schie, Kevin; van Veen, Suzanne C.; Engelhard, Iris M.; Klugkist, Irene; van den Hout, Marcel A.

2016-01-01

Background In eye movement desensitization and reprocessing (EMDR), patients make eye movements (EM) while recalling traumatic memories. Making EM taxes working memory (WM), which leaves less resources available for imagery of the memory. This reduces memory vividness and emotionality during future recalls. WM theory predicts that individuals with small working memory capacities (WMCs) benefit more from low levels of taxing (i.e., slow EM) whereas individuals with large WMC benefit more from high levels of taxing (i.e., fast EM). Objective We experimentally examined and tested four prespecified hypotheses regarding the role of WMC and EM speed in reducing emotionality and vividness ratings: 1) EM—regardless of WMC and EM speed—are more effective compared to no dual task, 2) increasing EM speed only affects the decrease in memory ratings irrespective of WMC, 3) low-WMC individuals—compared to high-WMC individuals—benefit more from making either type of EM, 4) the EM intervention is most effective when—as predicted by WM theory—EM are adjusted to WMC. Method Undergraduates with low (n=31) or high (n=35) WMC recalled three emotional memories and rated vividness and emotionality before and after each condition (recall only, recall + slow EM, and recall + fast EM). Results Contrary to the theory, the data do not support the hypothesis that EM speed should be adjusted to WMC (hypothesis 4). However, the data show that a dual task in general is more effective in reducing memory ratings than no dual task (hypothesis 1), and that a more cognitively demanding dual task increases the intervention's effectiveness (hypothesis 2). Conclusions Although adjusting EM speed to an individual's WMC seems a straightforward clinical implication, the data do not show any indication that such a titration is helpful. PMID:27387843

Method for prefetching non-contiguous data structures

DOEpatents

Blumrich, Matthias A [Ridgefield, CT; Chen, Dong [Croton On Hudson, NY; Coteus, Paul W [Yorktown Heights, NY; Gara, Alan G [Mount Kisco, NY; Giampapa, Mark E [Irvington, NY; Heidelberger, Philip [Cortlandt Manor, NY; Hoenicke, Dirk [Ossining, NY; Ohmacht, Martin [Brewster, NY; Steinmacher-Burow, Burkhard D [Mount Kisco, NY; Takken, Todd E [Mount Kisco, NY; Vranas, Pavlos M [Bedford Hills, NY

2009-05-05

A low latency memory system access is provided in association with a weakly-ordered multiprocessor system. Each processor in the multiprocessor shares resources, and each shared resource has an associated lock within a locking device that provides support for synchronization between the multiple processors in the multiprocessor and the orderly sharing of the resources. A processor only has permission to access a resource when it owns the lock associated with that resource, and an attempt by a processor to own a lock requires only a single load operation, rather than a traditional atomic load followed by store, such that the processor only performs a read operation and the hardware locking device performs a subsequent write operation rather than the processor. A simple perfecting for non-contiguous data structures is also disclosed. A memory line is redefined so that in addition to the normal physical memory data, every line includes a pointer that is large enough to point to any other line in the memory, wherein the pointers to determine which memory line to prefect rather than some other predictive algorithm. This enables hardware to effectively prefect memory access patterns that are non-contiguous, but repetitive.

The effect of visual salience on memory-based choices.

PubMed

Pooresmaeili, Arezoo; Bach, Dominik R; Dolan, Raymond J

2014-02-01

Deciding whether a stimulus is the "same" or "different" from a previous presented one involves integrating among the incoming sensory information, working memory, and perceptual decision making. Visual selective attention plays a crucial role in selecting the relevant information that informs a subsequent course of action. Previous studies have mainly investigated the role of visual attention during the encoding phase of working memory tasks. In this study, we investigate whether manipulation of bottom-up attention by changing stimulus visual salience impacts on later stages of memory-based decisions. In two experiments, we asked subjects to identify whether a stimulus had either the same or a different feature to that of a memorized sample. We manipulated visual salience of the test stimuli by varying a task-irrelevant feature contrast. Subjects chose a visually salient item more often when they looked for matching features and less often so when they looked for a nonmatch. This pattern of results indicates that salient items are more likely to be identified as a match. We interpret the findings in terms of capacity limitations at a comparison stage where a visually salient item is more likely to exhaust resources leading it to be prematurely parsed as a match.

Cultural resource applications for a GIS: Stone conservation at Jefferson and Lincoln Memorials

USGS Publications Warehouse

Joly, Kyle; Donald, Tony; Comer, Douglas

1998-01-01

Geographical information systems are rapidly becoming essential tools for land management. They provide a way to link landscape features to the wide variety of information that managers must consider when formulating plans for a site, designing site improvement and restoration projects, determining maintenance projects and protocols, and even interpreting the site. At the same time, they can be valuable research tools.Standing structures offer a different sort of geography, even though a humanly contrived one. Therefore, the capability of a geographical information system (GIS) to link geographical units to the information pertinent to the site and resource management can be employed in the management of standing structures. This was the idea that inspired the use of a GIS software, ArcView, to link computer aided design CAD) drawings of the Jefferson and Lincoln Memorials with inventories of the stones in the memorials. Both the CAD drawings and the inventory were in existence; what remained to be done was to modify the CAD files and place the inventory in an appropriately designed computerized database, and then to link the two in a GIS project. This work was carried out at the NPS Denver Service Center, Resource Planning Group, Applied Archaeology Center (DSC-RPG-AAC), in Silver Spring, Maryland, with the assistance of US/ICOMOS summer interns Katja Marasovic (Croatia) and Rastislav Gromnica (Slovakia), under the supervision of AAC office manager Douglas Comer. Project guidance was provided by Tony Donald, the Denver Service Center (DSC) project architect for the restoration of the Jefferson and Lincoln Memorials, and GIS consultation services by Kyle Joly.

Research about Memory Detection Based on the Embedded Platform

NASA Astrophysics Data System (ADS)

Sun, Hao; Chu, Jian

As is known to us all, the resources of memory detection of the embedded systems are very limited. Taking the Linux-based embedded arm as platform, this article puts forward two efficient memory detection technologies according to the characteristics of the embedded software. Especially for the programs which need specific libraries, the article puts forwards portable memory detection methods to help program designers to reduce human errors,improve programming quality and therefore make better use of the valuable embedded memory resource.

Task Experience as a Boundary Condition for the Negative Effects of Irrelevant Information on Learning

ERIC Educational Resources Information Center

Rop, Gertjan; van Wermeskerken, Margot; de Nooijer, Jacqueline A.; Verkoeijen, Peter P. J. L.; van Gog, Tamara

2018-01-01

Research on multimedia learning has shown that learning is hampered when a multimedia message includes extraneous information that is not relevant for the task, because processing the extraneous information uses up scarce attention and working memory resources. However, eye-tracking research suggests that task experience might be a boundary…

The Two Sides of Sensory-Cognitive Interactions: Effects of Age, Hearing Acuity, and Working Memory Span on Sentence Comprehension.

PubMed

DeCaro, Renee; Peelle, Jonathan E; Grossman, Murray; Wingfield, Arthur

2016-01-01

Reduced hearing acuity is among the most prevalent of chronic medical conditions among older adults. An experiment is reported in which comprehension of spoken sentences was tested for older adults with good hearing acuity or with a mild-to-moderate hearing loss, and young adults with age-normal hearing. Comprehension was measured by participants' ability to determine the agent of an action in sentences that expressed this relation with a syntactically less complex subject-relative construction or a syntactically more complex object-relative construction. Agency determination was further challenged by inserting a prepositional phrase into sentences between the person performing an action and the action being performed. As a control, prepositional phrases of equivalent length were also inserted into sentences in a non-disruptive position. Effects on sentence comprehension of age, hearing acuity, prepositional phrase placement and sound level of stimulus presentations appeared only for comprehension of sentences with the more syntactically complex object-relative structures. Working memory as tested by reading span scores accounted for a significant amount of the variance in comprehension accuracy. Once working memory capacity and hearing acuity were taken into account, chronological age among the older adults contributed no further variance to comprehension accuracy. Results are discussed in terms of the positive and negative effects of sensory-cognitive interactions in comprehension of spoken sentences and lend support to a framework in which domain-general executive resources, notably verbal working memory, play a role in both linguistic and perceptual processing.

Effects of reducing attentional resources on implicit and explicit memory after severe traumatic brain injury.

PubMed

Watt, S; Shores, E A; Kinoshita, S

1999-07-01

Implicit and explicit memory were examined in individuals with severe traumatic brain injury (TBI) under conditions of full and divided attention. Participants included 12 individuals with severe TBI and 12 matched controls. In Experiment 1, participants carried out an implicit test of word-stem completion and an explicit test of cued recall. Results demonstrated that TBI participants exhibited impaired explicit memory but preserved implicit memory. In Experiment 2, a significant reduction in the explicit memory performance of both TBI and control participants, as well as a significant decrease in the implicit memory performance of TBI participants, was achieved by reducing attentional resources at encoding. These results indicated that performance on an implicit task of word-stem completion may require the availability of additional attentional resources that are not preserved after severe TBI.

Memory, not just perception, plays an important role in terrestrial mammalian migration

PubMed Central

Mueller, Thomas

2017-01-01

One of the key questions regarding the underlying mechanisms of mammalian land migrations is how animals select where to go. Most studies assume perception of resources as the navigational mechanism. The possible role of memory that would allow forecasting conditions at distant locations and times based on information about environmental conditions from previous years has been little studied. We study migrating zebra in Botswana using an individual-based simulation model, where perceptually guided individuals use currently sensed resources at different perceptual ranges, while memory-guided individuals use long-term averages of past resources to forecast future conditions. We compare simulated individuals guided by perception or memory on resource landscapes of remotely sensed vegetation data to trajectories of GPS-tagged zebras. Our results show that memory provides a clear signal that best directs migrants to their destination compared to perception at even the largest perceptual ranges. Zebras modelled with memory arrived two to four times, or up to 100 km, closer to the migration destination than those using perception. We suggest that memory in addition to perception is important for directing ungulate migration. Furthermore, our findings are important for the conservation of migratory mammals, as memory informing direction suggests migration routes could be relatively inflexible. PMID:28539516

Memory, not just perception, plays an important role in terrestrial mammalian migration.

PubMed

Bracis, Chloe; Mueller, Thomas

2017-05-31

One of the key questions regarding the underlying mechanisms of mammalian land migrations is how animals select where to go. Most studies assume perception of resources as the navigational mechanism. The possible role of memory that would allow forecasting conditions at distant locations and times based on information about environmental conditions from previous years has been little studied. We study migrating zebra in Botswana using an individual-based simulation model, where perceptually guided individuals use currently sensed resources at different perceptual ranges, while memory-guided individuals use long-term averages of past resources to forecast future conditions. We compare simulated individuals guided by perception or memory on resource landscapes of remotely sensed vegetation data to trajectories of GPS-tagged zebras. Our results show that memory provides a clear signal that best directs migrants to their destination compared to perception at even the largest perceptual ranges. Zebras modelled with memory arrived two to four times, or up to 100 km, closer to the migration destination than those using perception. We suggest that memory in addition to perception is important for directing ungulate migration. Furthermore, our findings are important for the conservation of migratory mammals, as memory informing direction suggests migration routes could be relatively inflexible. © 2017 The Author(s).

The effect of non-visual working memory load on top-down modulation of visual processing

PubMed Central

Rissman, Jesse; Gazzaley, Adam; D'Esposito, Mark

2009-01-01

While a core function of the working memory (WM) system is the active maintenance of behaviorally relevant sensory representations, it is also critical that distracting stimuli are appropriately ignored. We used functional magnetic resonance imaging to examine the role of domain-general WM resources in the top-down attentional modulation of task-relevant and irrelevant visual representations. In our dual-task paradigm, each trial began with the auditory presentation of six random (high load) or sequentially-ordered (low load) digits. Next, two relevant visual stimuli (e.g., faces), presented amongst two temporally interspersed visual distractors (e.g., scenes), were to be encoded and maintained across a 7-sec delay interval, after which memory for the relevant images and digits was probed. When taxed by high load digit maintenance, participants exhibited impaired performance on the visual WM task and a selective failure to attenuate the neural processing of task-irrelevant scene stimuli. The over-processing of distractor scenes under high load was indexed by elevated encoding activity in a scene-selective region-of-interest relative to low load and passive viewing control conditions, as well as by improved long-term recognition memory for these items. In contrast, the load manipulation did not affect participants' ability to upregulate activity in this region when scenes were task-relevant. These results highlight the critical role of domain-general WM resources in the goal-directed regulation of distractor processing. Moreover, the consequences of increased WM load in young adults closely resemble the effects of cognitive aging on distractor filtering [Gazzaley et al., (2005) Nature Neuroscience 8, 1298-1300], suggesting the possibility of a common underlying mechanism. PMID:19397858

Non-Interfering Effects of Active Post-Encoding Tasks on Episodic Memory Consolidation in Humans

PubMed Central

Varma, Samarth; Takashima, Atsuko; Krewinkel, Sander; van Kooten, Maaike; Fu, Lily; Medendorp, W. Pieter; Kessels, Roy P. C.; Daselaar, Sander M.

2017-01-01

So far, studies that investigated interference effects of post-learning processes on episodic memory consolidation in humans have used tasks involving only complex and meaningful information. Such tasks require reallocation of general or encoding-specific resources away from consolidation-relevant activities. The possibility that interference can be elicited using a task that heavily taxes our limited brain resources, but has low semantic and hippocampal related long-term memory processing demands, has never been tested. We address this question by investigating whether consolidation could persist in parallel with an active, encoding-irrelevant, minimally semantic task, regardless of its high resource demands for cognitive processing. We distinguish the impact of such a task on consolidation based on whether it engages resources that are: (1) general/executive, or (2) specific/overlapping with the encoding modality. Our experiments compared subsequent memory performance across two post-encoding consolidation periods: quiet wakeful rest and a cognitively demanding n-Back task. Across six different experiments (total N = 176), we carefully manipulated the design of the n-Back task to target general or specific resources engaged in the ongoing consolidation process. In contrast to previous studies that employed interference tasks involving conceptual stimuli and complex processing demands, we did not find any differences between n-Back and rest conditions on memory performance at delayed test, using both recall and recognition tests. Our results indicate that: (1) quiet, wakeful rest is not a necessary prerequisite for episodic memory consolidation; and (2) post-encoding cognitive engagement does not interfere with memory consolidation when task-performance has minimal semantic and hippocampally-based episodic memory processing demands. We discuss our findings with reference to resource and reactivation-led interference theories. PMID:28424596

Non-Interfering Effects of Active Post-Encoding Tasks on Episodic Memory Consolidation in Humans.

PubMed

Varma, Samarth; Takashima, Atsuko; Krewinkel, Sander; van Kooten, Maaike; Fu, Lily; Medendorp, W Pieter; Kessels, Roy P C; Daselaar, Sander M

2017-01-01

So far, studies that investigated interference effects of post-learning processes on episodic memory consolidation in humans have used tasks involving only complex and meaningful information. Such tasks require reallocation of general or encoding-specific resources away from consolidation-relevant activities. The possibility that interference can be elicited using a task that heavily taxes our limited brain resources, but has low semantic and hippocampal related long-term memory processing demands, has never been tested. We address this question by investigating whether consolidation could persist in parallel with an active, encoding-irrelevant, minimally semantic task, regardless of its high resource demands for cognitive processing. We distinguish the impact of such a task on consolidation based on whether it engages resources that are: (1) general/executive, or (2) specific/overlapping with the encoding modality. Our experiments compared subsequent memory performance across two post-encoding consolidation periods: quiet wakeful rest and a cognitively demanding n-Back task. Across six different experiments (total N = 176), we carefully manipulated the design of the n-Back task to target general or specific resources engaged in the ongoing consolidation process. In contrast to previous studies that employed interference tasks involving conceptual stimuli and complex processing demands, we did not find any differences between n-Back and rest conditions on memory performance at delayed test, using both recall and recognition tests. Our results indicate that: (1) quiet, wakeful rest is not a necessary prerequisite for episodic memory consolidation; and (2) post-encoding cognitive engagement does not interfere with memory consolidation when task-performance has minimal semantic and hippocampally-based episodic memory processing demands. We discuss our findings with reference to resource and reactivation-led interference theories.

The Resource Usage Aware Backfilling

NASA Astrophysics Data System (ADS)

Guim, Francesc; Rodero, Ivan; Corbalan, Julita

Job scheduling policies for HPC centers have been extensively studied in the last few years, especially backfilling based policies. Almost all of these studies have been done using simulation tools. All the existent simulators use the runtime (either estimated or real) provided in the workload as a basis of their simulations. In our previous work we analyzed the impact on system performance of considering the resource sharing (memory bandwidth) of running jobs including a new resource model in the Alvio simulator. Based on this studies we proposed the LessConsume and LessConsume Threshold resource selection policies. Both are oriented to reduce the saturation of the shared resources thus increasing the performance of the system. The results showed how both resource allocation policies shown how the performance of the system can be improved by considering where the jobs are finally allocated.

Processing speed and visuospatial executive function predict visual working memory ability in older adults.

PubMed

Brown, Louise A; Brockmole, James R; Gow, Alan J; Deary, Ian J

2012-01-01

BACKGROUND/STUDY CONTEXT: Visual working memory (VWM) has been shown to be particularly age sensitive. Determining which measures share variance with this cognitive ability in older adults may help to elucidate the key factors underlying the effects of aging. Predictors of VWM (measured by a modified Visual Patterns Test) were investigated in a subsample (N = 44, mean age = 73) of older adults from the Lothian Birth Cohort 1936 (LBC1936; Deary et al., 2007 , BMC Geriatrics, 7, 28). Childhood intelligence (Moray House Test) and contemporaneous measures of processing speed (four-choice reaction time), executive function (verbal fluency; block design), and spatial working memory (backward spatial span), were assessed as potential predictors. All contemporaneous measures except verbal fluency were significantly associated with VWM, and processing speed had the largest effect size (r = -.53, p < .001). In linear regression analysis, even after adjusting for childhood intelligence, processing speed and the executive measure associated with visuospatial organization accounted for 35% of the variance in VWM. Processing speed may affect VWM performance in older adults via speed of encoding and/or rate of rehearsal, while executive resources specifically associated with visuospatial material are also important.

Trait and state anxiety is marked by increased working memory-related parietal BOLD signal.

PubMed

Ford, Talitha C; Simpson, Tamara; McPhee, Grace; Stough, Con; Downey, Luke A

2018-05-16

Anxiety is associated with compromised cognitive control functions, such as working memory. State and trait anxiety within the non-clinical population can be utilised to investigate potential neural markers for anxiety, which may help to elucidate potential prevention and intervention methods. Thirty-two healthy adults (20 female, 12 male), aged between 30 and 65 years, performed a 2-back task whilst fMRI BOLD signal was acquired using a 3T scanner. Mean BOLD signal was obtained in cognitive control network regions of interest of: left and right dorsolateral prefrontal cortex (DLPFC) and posterior parietal lobe (PPL), and medial prefrontal cortex (MPFC). State and trait anxiety levels were recorded. Higher overall anxiety was moderately associated with more left and right PPL BOLD signal; there was a weak relationship between anxiety and left DLPFC BOLD signal. MPFC BOLD signal and trait anxiety were moderately associated with overall 2-back task performance. These findings suggest that non-clinical anxiety affects the recruitment of cortical resources during working memory, but that anxiety does not impair performance during a 2-back task. Copyright © 2018 Elsevier B.V. All rights reserved.

Sensory processing patterns predict the integration of information held in visual working memory.

PubMed

Lowe, Matthew X; Stevenson, Ryan A; Wilson, Kristin E; Ouslis, Natasha E; Barense, Morgan D; Cant, Jonathan S; Ferber, Susanne

2016-02-01

Given the limited resources of visual working memory, multiple items may be remembered as an averaged group or ensemble. As a result, local information may be ill-defined, but these ensemble representations provide accurate diagnostics of the natural world by combining gist information with item-level information held in visual working memory. Some neurodevelopmental disorders are characterized by sensory processing profiles that predispose individuals to avoid or seek-out sensory stimulation, fundamentally altering their perceptual experience. Here, we report such processing styles will affect the computation of ensemble statistics in the general population. We identified stable adult sensory processing patterns to demonstrate that individuals with low sensory thresholds who show a greater proclivity to engage in active response strategies to prevent sensory overstimulation are less likely to integrate mean size information across a set of similar items and are therefore more likely to be biased away from the mean size representation of an ensemble display. We therefore propose the study of ensemble processing should extend beyond the statistics of the display, and should also consider the statistics of the observer. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Attentional distractor interference may be diminished by concurrent working memory load in normal participants and traumatic brain injury patients.

PubMed

Gil-Gómez de Liaño, Beatriz; Umiltà, Carlo; Stablum, Franca; Tebaldi, Francesca; Cantagallo, Anna

2010-12-01

A reduction in congruency effects under working memory (WM) load has been previously described using different attentional paradigms (e.g., Kim, Kim, & Chun, 2005; Smilek, Enns, Eastwood, & Merikle, 2006). One hypothesis is that different types of WM load have different effects on attentional selection, depending on whether a specific memory load demands resources in common with target or distractor processing. In particular, if information in WM is related to the distractors in the selective attention task, there is a reduction in distraction (Kim et al., 2005). However, although previous results seem to point to a decrease in interference under high WM load conditions (Kim et al., 2005), the lack of a neutral baseline for the congruency effects makes it difficult to differentiate between a decrease in interference or in facilitation. In the present work we included neutral trials in the task introduced by Kim et al. (2005) and tested normal participants and traumatic brain injury patients. Results support a reduction in the processing of distractors under WM load, at least for incongruent trials in both groups. Theoretical as well as applied implications are discussed. Copyright © 2010 Elsevier Inc. All rights reserved.

JANUS: A Compilation System for Balancing Parallelism and Performance in OpenVX

NASA Astrophysics Data System (ADS)

Omidian, Hossein; Lemieux, Guy G. F.

2018-04-01

Embedded systems typically do not have enough on-chip memory for entire an image buffer. Programming systems like OpenCV operate on entire image frames at each step, making them use excessive memory bandwidth and power. In contrast, the paradigm used by OpenVX is much more efficient; it uses image tiling, and the compilation system is allowed to analyze and optimize the operation sequence, specified as a compute graph, before doing any pixel processing. In this work, we are building a compilation system for OpenVX that can analyze and optimize the compute graph to take advantage of parallel resources in many-core systems or FPGAs. Using a database of prewritten OpenVX kernels, it automatically adjusts the image tile size as well as using kernel duplication and coalescing to meet a defined area (resource) target, or to meet a specified throughput target. This allows a single compute graph to target implementations with a wide range of performance needs or capabilities, e.g. from handheld to datacenter, that use minimal resources and power to reach the performance target.

Strategies for Energy Efficient Resource Management of Hybrid Programming Models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Dong; Supinski, Bronis de; Schulz, Martin

2013-01-01

Many scientific applications are programmed using hybrid programming models that use both message-passing and shared-memory, due to the increasing prevalence of large-scale systems with multicore, multisocket nodes. Previous work has shown that energy efficiency can be improved using software-controlled execution schemes that consider both the programming model and the power-aware execution capabilities of the system. However, such approaches have focused on identifying optimal resource utilization for one programming model, either shared-memory or message-passing, in isolation. The potential solution space, thus the challenge, increases substantially when optimizing hybrid models since the possible resource configurations increase exponentially. Nonetheless, with the accelerating adoptionmore » of hybrid programming models, we increasingly need improved energy efficiency in hybrid parallel applications on large-scale systems. In this work, we present new software-controlled execution schemes that consider the effects of dynamic concurrency throttling (DCT) and dynamic voltage and frequency scaling (DVFS) in the context of hybrid programming models. Specifically, we present predictive models and novel algorithms based on statistical analysis that anticipate application power and time requirements under different concurrency and frequency configurations. We apply our models and methods to the NPB MZ benchmarks and selected applications from the ASC Sequoia codes. Overall, we achieve substantial energy savings (8.74% on average and up to 13.8%) with some performance gain (up to 7.5%) or negligible performance loss.« less

Reward-dependent modulation of working memory is associated with negative symptoms in schizophrenia.

PubMed

Hager, Oliver M; Kirschner, Matthias; Bischof, Martin; Hartmann-Riemer, Matthias N; Kluge, Agne; Seifritz, Erich; Tobler, Philippe N; Kaiser, Stefan

2015-10-01

The negative symptoms of schizophrenia have been associated with altered neural activity during both reward processing and cognitive processing. Even though increasing evidence suggests a strong interaction between these two domains, it has not been studied in relation to negative symptoms. To elucidate neural mechanisms of the reward-cognition interaction, we applied a letter variant of the n-back working memory task and varied the financial incentives for performance. In the interaction contrast, we found a significantly activated cluster in the rostral anterior cingulate cortex (ACC), the middle frontal gyrus, and the bilateral superior frontal gyrus. The interaction did not differ significantly between the patient group and a healthy control group, suggesting that patients with schizophrenia are on average able to integrate reward information and utilize this information to maximize cognitive performance. However within the patient group, we found a significant inverse correlation of ACC activity with the factor diminished expression. This finding is consistent with the model that a lack of available cognitive resources leads to diminished expression. We therefore argue that patients with diminished expression have difficulties in recruiting additional cognitive resources (as implemented in the ACC) in response to an anticipated reward. Due to this lack of cognitive resources, less processing capacity is available for effective expression, resulting in diminished expressive behavior. Copyright © 2015 Elsevier B.V. All rights reserved.

Is the Link from Working Memory to Analogy Causal? No Analogy Improvements following Working Memory Training Gains

PubMed Central

Richey, J. Elizabeth; Phillips, Jeffrey S.; Schunn, Christian D.; Schneider, Walter

2014-01-01

Analogical reasoning has been hypothesized to critically depend upon working memory through correlational data [1], but less work has tested this relationship through experimental manipulation [2]. An opportunity for examining the connection between working memory and analogical reasoning has emerged from the growing, although somewhat controversial, body of literature suggests complex working memory training can sometimes lead to working memory improvements that transfer to novel working memory tasks. This study investigated whether working memory improvements, if replicated, would increase analogical reasoning ability. We assessed participants’ performance on verbal and visual analogy tasks after a complex working memory training program incorporating verbal and spatial tasks [3], [4]. Participants’ improvements on the working memory training tasks transferred to other short-term and working memory tasks, supporting the possibility of broad effects of working memory training. However, we found no effects on analogical reasoning. We propose several possible explanations for the lack of an impact of working memory improvements on analogical reasoning. PMID:25188356

Localized Fluctuant Oscillatory Activity by Working Memory Load: A Simultaneous EEG-fMRI Study.

PubMed

Zhao, Xiaojie; Li, Xiaoyun; Yao, Li

2017-01-01

Working memory (WM) is a resource-limited memory system for temporary storage and processing of brain information during the execution of cognitive tasks. Increased WM load will increase the amount and difficulty of memory information. Several studies have used electroencephalography (EEG) or functional magnetic resonance imaging (fMRI) to explore load-dependent cognition processing according to the time courses of electrophysiological activity or the spatial pattern of blood oxygen metabolic activity. However, the relationships between these two activities and the underlying neural mechanism are still unclear. In this study, using simultaneously collected EEG and fMRI data under an n-back verbal WM task, we modeled the spectral perturbation of EEG oscillation and fMRI activation through joint independent component analysis (JICA). Multi-channel oscillation features were also introduced into the JICA model for further analysis. The results showed that time-locked activity of theta and beta were modulated by memory load in the early stimuli evaluation stage, corresponding to the enhanced activation in the frontal and parietal lobe, which were involved in stimulus discrimination, information encoding and delay-period activity. In the late response selection stage, alpha and gamma activity changes dependent on the load correspond to enhanced activation in the areas of frontal, temporal and parietal lobes, which played important roles in attention, information extraction and memory retention. These findings suggest that the increases in memory load not only affect the intensity and time course of the EEG activities, but also lead to the enhanced activation of brain regions which plays different roles during different time periods of cognitive process of WM.

The impact of early visual cortex transcranial magnetic stimulation on visual working memory precision and guess rate.

PubMed

Rademaker, Rosanne L; van de Ven, Vincent G; Tong, Frank; Sack, Alexander T

2017-01-01

Neuroimaging studies have demonstrated that activity patterns in early visual areas predict stimulus properties actively maintained in visual working memory. Yet, the mechanisms by which such information is represented remain largely unknown. In this study, observers remembered the orientations of 4 briefly presented gratings, one in each quadrant of the visual field. A 10Hz Transcranial Magnetic Stimulation (TMS) triplet was applied directly at stimulus offset, or midway through a 2-second delay, targeting early visual cortex corresponding retinotopically to a sample item in the lower hemifield. Memory for one of the four gratings was probed at random, and participants reported this orientation via method of adjustment. Recall errors were smaller when the visual field location targeted by TMS overlapped with that of the cued memory item, compared to errors for stimuli probed diagonally to TMS. This implied topographic storage of orientation information, and a memory-enhancing effect at the targeted location. Furthermore, early pulses impaired performance at all four locations, compared to late pulses. Next, response errors were fit empirically using a mixture model to characterize memory precision and guess rates. Memory was more precise for items proximal to the pulse location, irrespective of pulse timing. Guesses were more probable with early TMS pulses, regardless of stimulus location. Thus, while TMS administered at the offset of the stimulus array might disrupt early-phase consolidation in a non-topographic manner, TMS also boosts the precise representation of an item at its targeted retinotopic location, possibly by increasing attentional resources or by injecting a beneficial amount of noise.

The impact of early visual cortex transcranial magnetic stimulation on visual working memory precision and guess rate

PubMed Central

van de Ven, Vincent G.; Tong, Frank; Sack, Alexander T.

2017-01-01

Neuroimaging studies have demonstrated that activity patterns in early visual areas predict stimulus properties actively maintained in visual working memory. Yet, the mechanisms by which such information is represented remain largely unknown. In this study, observers remembered the orientations of 4 briefly presented gratings, one in each quadrant of the visual field. A 10Hz Transcranial Magnetic Stimulation (TMS) triplet was applied directly at stimulus offset, or midway through a 2-second delay, targeting early visual cortex corresponding retinotopically to a sample item in the lower hemifield. Memory for one of the four gratings was probed at random, and participants reported this orientation via method of adjustment. Recall errors were smaller when the visual field location targeted by TMS overlapped with that of the cued memory item, compared to errors for stimuli probed diagonally to TMS. This implied topographic storage of orientation information, and a memory-enhancing effect at the targeted location. Furthermore, early pulses impaired performance at all four locations, compared to late pulses. Next, response errors were fit empirically using a mixture model to characterize memory precision and guess rates. Memory was more precise for items proximal to the pulse location, irrespective of pulse timing. Guesses were more probable with early TMS pulses, regardless of stimulus location. Thus, while TMS administered at the offset of the stimulus array might disrupt early-phase consolidation in a non-topographic manner, TMS also boosts the precise representation of an item at its targeted retinotopic location, possibly by increasing attentional resources or by injecting a beneficial amount of noise. PMID:28384347

Happiness increases verbal and spatial working memory capacity where sadness does not: Emotion, working memory and executive control.

PubMed

Storbeck, Justin; Maswood, Raeya

2016-08-01

The effects of emotion on working memory and executive control are often studied in isolation. Positive mood enhances verbal and impairs spatial working memory, whereas negative mood enhances spatial and impairs verbal working memory. Moreover, positive mood enhances executive control, whereas negative mood has little influence. We examined how emotion influences verbal and spatial working memory capacity, which requires executive control to coordinate between holding information in working memory and completing a secondary task. We predicted that positive mood would improve both verbal and spatial working memory capacity because of its influence on executive control. Positive, negative and neutral moods were induced followed by completing a verbal (Experiment 1) or spatial (Experiment 2) working memory operation span task to assess working memory capacity. Positive mood enhanced working memory capacity irrespective of the working memory domain, whereas negative mood had no influence on performance. Thus, positive mood was more successful holding information in working memory while processing task-irrelevant information, suggesting that the influence mood has on executive control supersedes the independent effects mood has on domain-specific working memory.

Preexisting semantic representation improves working memory performance in the visuospatial domain.

PubMed

Rudner, Mary; Orfanidou, Eleni; Cardin, Velia; Capek, Cheryl M; Woll, Bencie; Rönnberg, Jerker

2016-05-01

Working memory (WM) for spoken language improves when the to-be-remembered items correspond to preexisting representations in long-term memory. We investigated whether this effect generalizes to the visuospatial domain by administering a visual n-back WM task to deaf signers and hearing signers, as well as to hearing nonsigners. Four different kinds of stimuli were presented: British Sign Language (BSL; familiar to the signers), Swedish Sign Language (SSL; unfamiliar), nonsigns, and nonlinguistic manual actions. The hearing signers performed better with BSL than with SSL, demonstrating a facilitatory effect of preexisting semantic representation. The deaf signers also performed better with BSL than with SSL, but only when WM load was high. No effect of preexisting phonological representation was detected. The deaf signers performed better than the hearing nonsigners with all sign-based materials, but this effect did not generalize to nonlinguistic manual actions. We argue that deaf signers, who are highly reliant on visual information for communication, develop expertise in processing sign-based items, even when those items do not have preexisting semantic or phonological representations. Preexisting semantic representation, however, enhances the quality of the gesture-based representations temporarily maintained in WM by this group, thereby releasing WM resources to deal with increased load. Hearing signers, on the other hand, may make strategic use of their speech-based representations for mnemonic purposes. The overall pattern of results is in line with flexible-resource models of WM.

Rhesus monkeys employ a procedural strategy to reduce working memory load in a self-ordered spatial search task

PubMed Central

Taffe, Michael A.; Taffe, William J.

2011-01-01

Several nonhuman primate species have been reported to employ a distance-minimizing, traveling salesman-like, strategy during foraging as well as in experimental spatial search tasks involving lesser amounts of locomotion. Spatial sequencing may optimize performance by reducing reference or episodic memory loads, locomotor costs, competition or other demands. A computerized self-ordered spatial search (SOSS) memory task has been adapted from a human neuropsychological testing battery (CANTAB, Cambridge Cognition, Ltd) for use in monkeys. Accurate completion of a trial requires sequential responses to colored boxes in two or more spatial locations without repetition of a previous location. Marmosets have been reported to employ a circling pattern of search, suggesting spontaneous adoption of a strategy to reduce working memory load. In this study the SOSS performance of rhesus monkeys was assessed to determine if the use of a distance-minimizing search path enhances accuracy. A novel strategy score, independent of the trial difficulty and arrangement of boxes, has been devised. Analysis of the performance of 21 monkeys trained on SOSS over two years shows that a distance-minimizing search strategy is associated with improved accuracy. This effect is observed within individuals as they improve over many cumulative sessions of training on the task and across individuals at any given level of training. Erroneous trials were associated with a failure to deploy the strategy. It is concluded that the effect of utilizing the strategy on this locomotion-free, laboratory task is to enhance accuracy by reducing demands on spatial working memory resources. PMID:21840507

Cognitive spare capacity: evaluation data and its association with comprehension of dynamic conversations

PubMed Central

Keidser, Gitte; Best, Virginia; Freeston, Katrina; Boyce, Alexandra

2015-01-01

It is well-established that communication involves the working memory system, which becomes increasingly engaged in understanding speech as the input signal degrades. The more resources allocated to recovering a degraded input signal, the fewer resources, referred to as cognitive spare capacity (CSC), remain for higher-level processing of speech. Using simulated natural listening environments, the aims of this paper were to (1) evaluate an English version of a recently introduced auditory test to measure CSC that targets the updating process of the executive function, (2) investigate if the test predicts speech comprehension better than the reading span test (RST) commonly used to measure working memory capacity, and (3) determine if the test is sensitive to increasing the number of attended locations during listening. In Experiment I, the CSC test was presented using a male and a female talker, in quiet and in spatially separated babble- and cafeteria-noises, in an audio-only and in an audio-visual mode. Data collected on 21 listeners with normal and impaired hearing confirmed that the English version of the CSC test is sensitive to population group, noise condition, and clarity of speech, but not presentation modality. In Experiment II, performance by 27 normal-hearing listeners on a novel speech comprehension test presented in noise was significantly associated with working memory capacity, but not with CSC. Moreover, this group showed no significant difference in CSC as the number of talker locations in the test increased. There was no consistent association between the CSC test and the RST. It is recommended that future studies investigate the psychometric properties of the CSC test, and examine its sensitivity to the complexity of the listening environment in participants with both normal and impaired hearing. PMID:25999904

Retrieval and Monitoring Processes during Visual Working Memory: An ERP Study of the Benefit of Visual Semantics

PubMed Central

Orme, Elizabeth; Brown, Louise A.; Riby, Leigh M.

2017-01-01

In this study, we examined electrophysiological indices of episodic remembering whilst participants recalled novel shapes, with and without semantic content, within a visual working memory paradigm. The components of interest were the parietal episodic (PE; 400–800 ms) and late posterior negativity (LPN; 500–900 ms), as these have previously been identified as reliable markers of recollection and post-retrieval monitoring, respectively. Fifteen young adults completed a visual matrix patterns task, assessing memory for low and high semantic visual representations. Matrices with either low semantic or high semantic content (containing familiar visual forms) were briefly presented to participants for study (1500 ms), followed by a retention interval (6000 ms) and finally a same/different recognition phase. The event-related potentials of interest were tracked from the onset of the recognition test stimuli. Analyses revealed equivalent amplitude for the earlier PE effect for the processing of both low and high semantic stimulus types. However, the LPN was more negative-going for the processing of the low semantic stimuli. These data are discussed in terms of relatively ‘pure’ and complete retrieval of high semantic items, where support can readily be recruited from semantic memory. However, for the low semantic items additional executive resources, as indexed by the LPN, are recruited when memory monitoring and uncertainty exist in order to recall previously studied items more effectively. PMID:28725203

Retrieval and Monitoring Processes during Visual Working Memory: An ERP Study of the Benefit of Visual Semantics.

PubMed

Orme, Elizabeth; Brown, Louise A; Riby, Leigh M

2017-01-01

In this study, we examined electrophysiological indices of episodic remembering whilst participants recalled novel shapes, with and without semantic content, within a visual working memory paradigm. The components of interest were the parietal episodic (PE; 400-800 ms) and late posterior negativity (LPN; 500-900 ms), as these have previously been identified as reliable markers of recollection and post-retrieval monitoring, respectively. Fifteen young adults completed a visual matrix patterns task, assessing memory for low and high semantic visual representations. Matrices with either low semantic or high semantic content (containing familiar visual forms) were briefly presented to participants for study (1500 ms), followed by a retention interval (6000 ms) and finally a same/different recognition phase. The event-related potentials of interest were tracked from the onset of the recognition test stimuli. Analyses revealed equivalent amplitude for the earlier PE effect for the processing of both low and high semantic stimulus types. However, the LPN was more negative-going for the processing of the low semantic stimuli. These data are discussed in terms of relatively 'pure' and complete retrieval of high semantic items, where support can readily be recruited from semantic memory. However, for the low semantic items additional executive resources, as indexed by the LPN, are recruited when memory monitoring and uncertainty exist in order to recall previously studied items more effectively.

The Relation between Acquisition of a Theory of Mind and the Capacity to Hold in Mind.

ERIC Educational Resources Information Center

Gordon, Anne C. L.; Olson, David R.

1998-01-01

Tested hypothesized relationship between development of a theory of mind and increasing computational resources in 3- to 5-year olds. Found that the correlations between performance on theory of mind tasks and dual processing tasks were as high as r=.64, suggesting that changes in working memory capacity allow the expression of, and arguably the…

To extend the legislative authority of the Adams Memorial Foundation to establish a commemorative work in honor of former President John Adams and his legacy, and for other purposes.

THOMAS, 113th Congress

Rep. Lynch, Stephen F. [D-MA-8

2013-12-19

Senate - 07/23/2014 Received in the Senate and Read twice and referred to the Committee on Energy and Natural Resources. (All Actions) Tracker: This bill has the status Passed HouseHere are the steps for Status of Legislation:

Huffman coding in advanced audio coding standard

NASA Astrophysics Data System (ADS)

Brzuchalski, Grzegorz

2012-05-01

This article presents several hardware architectures of Advanced Audio Coding (AAC) Huffman noiseless encoder, its optimisations and working implementation. Much attention has been paid to optimise the demand of hardware resources especially memory size. The aim of design was to get as short binary stream as possible in this standard. The Huffman encoder with whole audio-video system has been implemented in FPGA devices.

Non-Markovianity-assisted high-fidelity Deutsch-Jozsa algorithm in diamond

NASA Astrophysics Data System (ADS)

Dong, Yang; Zheng, Yu; Li, Shen; Li, Cong-Cong; Chen, Xiang-Dong; Guo, Guang-Can; Sun, Fang-Wen

2018-01-01

The memory effects in non-Markovian quantum dynamics can induce the revival of quantum coherence, which is believed to provide important physical resources for quantum information processing (QIP). However, no real quantum algorithms have been demonstrated with the help of such memory effects. Here, we experimentally implemented a non-Markovianity-assisted high-fidelity refined Deutsch-Jozsa algorithm (RDJA) with a solid spin in diamond. The memory effects can induce pronounced non-monotonic variations in the RDJA results, which were confirmed to follow a non-Markovian quantum process by measuring the non-Markovianity of the spin system. By applying the memory effects as physical resources with the assistance of dynamical decoupling, the probability of success of RDJA was elevated above 97% in the open quantum system. This study not only demonstrates that the non-Markovianity is an important physical resource but also presents a feasible way to employ this physical resource. It will stimulate the application of the memory effects in non-Markovian quantum dynamics to improve the performance of practical QIP.

Time and interference: Effects on working memory.

PubMed

Botto, Marta; Palladino, Paola

2016-05-01

This study tested predictions from the time-based resource-sharing (TBRS) model with a classical verbal working memory (WM) task, where target and non-target information interfere strongly with each other. Different predictions can be formulated according to the dominant perspectives (TBRS and interference hypothesis) on the role of inhibitory control in WM task performance. Here, we aimed to trace the activation of irrelevant information, examining priming effects in a lexical decision task immediately following WM recall. Results indicate the roles of both time and interference constraints in determining task performance. In particular, the role of time available seemed crucial at the highest WM loads (i.e., 3 and 4 memoranda). These were also associated with a higher activation of no-longer-relevant information but, in this case, independently from time available for processing. © 2015 The British Psychological Society.

Verbal working memory predicts co-speech gesture: evidence from individual differences.

PubMed

Gillespie, Maureen; James, Ariel N; Federmeier, Kara D; Watson, Duane G

2014-08-01

Gesture facilitates language production, but there is debate surrounding its exact role. It has been argued that gestures lighten the load on verbal working memory (VWM; Goldin-Meadow, Nusbaum, Kelly, & Wagner, 2001), but gestures have also been argued to aid in lexical retrieval (Krauss, 1998). In the current study, 50 speakers completed an individual differences battery that included measures of VWM and lexical retrieval. To elicit gesture, each speaker described short cartoon clips immediately after viewing. Measures of lexical retrieval did not predict spontaneous gesture rates, but lower VWM was associated with higher gesture rates, suggesting that gestures can facilitate language production by supporting VWM when resources are taxed. These data also suggest that individual variability in the propensity to gesture is partly linked to cognitive capacities. Copyright © 2014 Elsevier B.V. All rights reserved.

The influence of working memory load on response inhibition in children with attention-deficit/hyperactivity disorder or reading disorder.

PubMed

Van De Voorde, Séverine; Roeyers, Herbert; Verté, Sylvie; Wiersema, Jan Roelf

2011-08-01

The aim of the present study was to examine the relationship between response inhibition and working memory in 8-12-year-old children with attention-deficit/hyperactivity disorder (ADHD; n = 19), reading disorder (RD; n = 17), ADHD + RD (n = 21), and control children (n = 19). For the first time a within-task methodology was used to study the combined effect of both executive functions on a common measure of task performance in two often comorbid childhood disorders, ADHD and RD. We found evidence of an interaction between both domains, suggesting that they rely on a common pool of resources. In addition, we found that children with ADHD or RD were not more seriously affected by the combined load of both executive functions than children without ADHD or RD.

Drift in Neural Population Activity Causes Working Memory to Deteriorate Over Time.

PubMed

Schneegans, Sebastian; Bays, Paul M

2018-05-23

Short-term memories are thought to be maintained in the form of sustained spiking activity in neural populations. Decreases in recall precision observed with increasing number of memorized items can be accounted for by a limit on total spiking activity, resulting in fewer spikes contributing to the representation of each individual item. Longer retention intervals likewise reduce recall precision, but it is unknown what changes in population activity produce this effect. One possibility is that spiking activity becomes attenuated over time, such that the same mechanism accounts for both effects of set size and retention duration. Alternatively, reduced performance may be caused by drift in the encoded value over time, without a decrease in overall spiking activity. Human participants of either sex performed a variable-delay cued recall task with a saccadic response, providing a precise measure of recall latency. Based on a spike integration model of decision making, if the effects of set size and retention duration are both caused by decreased spiking activity, we would predict a fixed relationship between recall precision and response latency across conditions. In contrast, the drift hypothesis predicts no systematic changes in latency with increasing delays. Our results show both an increase in latency with set size, and a decrease in response precision with longer delays within each set size, but no systematic increase in latency for increasing delay durations. These results were quantitatively reproduced by a model based on a limited neural resource in which working memories drift rather than decay with time. SIGNIFICANCE STATEMENT Rapid deterioration over seconds is a defining feature of short-term memory, but what mechanism drives this degradation of internal representations? Here, we extend a successful population coding model of working memory by introducing possible mechanisms of delay effects. We show that a decay in neural signal over time predicts that the time required for memory retrieval will increase with delay, whereas a random drift in the stored value predicts no effect of delay on retrieval time. Testing these predictions in a multi-item memory task with an eye movement response, we identified drift as a key mechanism of memory decline. These results provide evidence for a dynamic spiking basis for working memory, in contrast to recent proposals of activity-silent storage. Copyright © 2018 Schneegans and Bays.

Memory Effects on Movement Behavior in Animal Foraging

PubMed Central

Bracis, Chloe; Gurarie, Eliezer; Van Moorter, Bram; Goodwin, R. Andrew

2015-01-01

An individual’s choices are shaped by its experience, a fundamental property of behavior important to understanding complex processes. Learning and memory are observed across many taxa and can drive behaviors, including foraging behavior. To explore the conditions under which memory provides an advantage, we present a continuous-space, continuous-time model of animal movement that incorporates learning and memory. Using simulation models, we evaluate the benefit memory provides across several types of landscapes with variable-quality resources and compare the memory model within a nested hierarchy of simpler models (behavioral switching and random walk). We find that memory almost always leads to improved foraging success, but that this effect is most marked in landscapes containing sparse, contiguous patches of high-value resources that regenerate relatively fast and are located in an otherwise devoid landscape. In these cases, there is a large payoff for finding a resource patch, due to size, value, or locational difficulty. While memory-informed search is difficult to differentiate from other factors using solely movement data, our results suggest that disproportionate spatial use of higher value areas, higher consumption rates, and consumption variability all point to memory influencing the movement direction of animals in certain ecosystems. PMID:26288228

Memory Effects on Movement Behavior in Animal Foraging.

PubMed

Bracis, Chloe; Gurarie, Eliezer; Van Moorter, Bram; Goodwin, R Andrew

2015-01-01

An individual's choices are shaped by its experience, a fundamental property of behavior important to understanding complex processes. Learning and memory are observed across many taxa and can drive behaviors, including foraging behavior. To explore the conditions under which memory provides an advantage, we present a continuous-space, continuous-time model of animal movement that incorporates learning and memory. Using simulation models, we evaluate the benefit memory provides across several types of landscapes with variable-quality resources and compare the memory model within a nested hierarchy of simpler models (behavioral switching and random walk). We find that memory almost always leads to improved foraging success, but that this effect is most marked in landscapes containing sparse, contiguous patches of high-value resources that regenerate relatively fast and are located in an otherwise devoid landscape. In these cases, there is a large payoff for finding a resource patch, due to size, value, or locational difficulty. While memory-informed search is difficult to differentiate from other factors using solely movement data, our results suggest that disproportionate spatial use of higher value areas, higher consumption rates, and consumption variability all point to memory influencing the movement direction of animals in certain ecosystems.

A Malicious Pattern Detection Engine for Embedded Security Systems in the Internet of Things

PubMed Central

Oh, Doohwan; Kim, Deokho; Ro, Won Woo

2014-01-01

With the emergence of the Internet of Things (IoT), a large number of physical objects in daily life have been aggressively connected to the Internet. As the number of objects connected to networks increases, the security systems face a critical challenge due to the global connectivity and accessibility of the IoT. However, it is difficult to adapt traditional security systems to the objects in the IoT, because of their limited computing power and memory size. In light of this, we present a lightweight security system that uses a novel malicious pattern-matching engine. We limit the memory usage of the proposed system in order to make it work on resource-constrained devices. To mitigate performance degradation due to limitations of computation power and memory, we propose two novel techniques, auxiliary shifting and early decision. Through both techniques, we can efficiently reduce the number of matching operations on resource-constrained systems. Experiments and performance analyses show that our proposed system achieves a maximum speedup of 2.14 with an IoT object and provides scalable performance for a large number of patterns. PMID:25521382

Developmental memory capacity resources of typical children retrieving picture communication symbols using direct selection and visual linear scanning with fixed communication displays.

PubMed

Wagner, Barry T; Jackson, Heather M

2006-02-01

This study examined the cognitive demands of 2 selection techniques in augmentative and alternative communication (AAC), direct selection, and visual linear scanning, by determining the memory retrieval abilities of typically developing children when presented with fixed communication displays. One hundred twenty typical children from kindergarten, 1st, and 3rd grades were randomly assigned to either a direct selection or visual linear scanning group. Memory retrieval was assessed through word span using Picture Communication Symbols (PCSs). Participants were presented various numbers and arrays of PCSs and asked to retrieve them by placing identical graphic symbols on fixed communication displays with grid layouts. The results revealed that participants were able to retrieve more PCSs during direct selection than scanning. Additionally, 3rd-grade children retrieved more PCSs than kindergarten and 1st-grade children. An analysis on the type of errors during retrieval indicated that children were more successful at retrieving the correct PCSs than the designated location of those symbols on fixed communication displays. AAC practitioners should consider using direct selection over scanning whenever possible and account for anticipatory monitoring and pulses when scanning is used in the service delivery of children with little or no functional speech. Also, researchers should continue to investigate AAC selection techniques in relationship to working memory resources.

Superior Intraparietal Sulcus Controls the Variability of Visual Working Memory Precision.

PubMed

Galeano Weber, Elena M; Peters, Benjamin; Hahn, Tim; Bledowski, Christoph; Fiebach, Christian J

2016-05-18

Limitations of working memory (WM) capacity depend strongly on the cognitive resources that are available for maintaining WM contents in an activated state. Increasing the number of items to be maintained in WM was shown to reduce the precision of WM and to increase the variability of WM precision over time. Although WM precision was recently associated with neural codes particularly in early sensory cortex, we have so far no understanding of the neural bases underlying the variability of WM precision, and how WM precision is preserved under high load. To fill this gap, we combined human fMRI with computational modeling of behavioral performance in a delayed color-estimation WM task. Behavioral results replicate a reduction of WM precision and an increase of precision variability under high loads (5 > 3 > 1 colors). Load-dependent BOLD signals in primary visual cortex (V1) and superior intraparietal sulcus (IPS), measured during the WM task at 2-4 s after sample onset, were modulated by individual differences in load-related changes in the variability of WM precision. Although stronger load-related BOLD increase in superior IPS was related to lower increases in precision variability, thus stabilizing WM performance, the reverse was observed for V1. Finally, the detrimental effect of load on behavioral precision and precision variability was accompanied by a load-related decline in the accuracy of decoding the memory stimuli (colors) from left superior IPS. We suggest that the superior IPS may contribute to stabilizing visual WM performance by reducing the variability of memory precision in the face of higher load. This study investigates the neural bases of capacity limitations in visual working memory by combining fMRI with cognitive modeling of behavioral performance, in human participants. It provides evidence that the superior intraparietal sulcus (IPS) is a critical brain region that influences the variability of visual working memory precision between and within individuals (Fougnie et al., 2012; van den Berg et al., 2012) under increased memory load, possibly in cooperation with perceptual systems of the occipital cortex. These findings substantially extend our understanding of the nature of capacity limitations in visual working memory and their neural bases. Our work underlines the importance of integrating cognitive modeling with univariate and multivariate methods in fMRI research, thus improving our knowledge of brain-behavior relationships. Copyright © 2016 the authors 0270-6474/16/365623-13$15.00/0.

Parietal-Occipital Interactions Underlying Control- and Representation-Related Processes in Working Memory for Nonspatial Visual Features.

PubMed

Gosseries, Olivia; Yu, Qing; LaRocque, Joshua J; Starrett, Michael J; Rose, Nathan S; Cowan, Nelson; Postle, Bradley R

2018-05-02

Although the manipulation of load is popular in visual working memory research, many studies confound general attentional demands with context binding by drawing memoranda from the same stimulus category. In this fMRI study of human observers (both sexes), we created high- versus low-binding conditions, while holding load constant, by comparing trials requiring memory for the direction of motion of one random dot kinematogram (RDK; 1M trials) versus for three RDKs (3M), or versus one RDK and two color patches (1M2C). Memory precision was highest for 1M trials and comparable for 3M and 1M2C trials. And although delay-period activity in occipital cortex did not differ between the three conditions, returning to baseline for all three, multivariate pattern analysis decoding of a remembered RDK from occipital cortex was also highest for 1M trials and comparable for 3M and 1M2C trials. Delay-period activity in intraparietal sulcus (IPS), although elevated for all three conditions, displayed more sensitivity to demands on context binding than to load per se. The 1M-to-3M increase in IPS signal predicted the 1M-to-3M declines in both behavioral and neural estimates of working memory precision. These effects strengthened along a caudal-to-rostral gradient, from IPS0 to IPS5. Context binding-independent load sensitivity was observed when analyses were lateralized and extended into PFC, with trend-level effects evident in left IPS and strong effects in left lateral PFC. These findings illustrate how visual working memory capacity limitations arise from multiple factors that each recruit dissociable brain systems. SIGNIFICANCE STATEMENT Visual working memory capacity predicts performance on a wide array of cognitive and real-world outcomes. At least two theoretically distinct factors are proposed to influence visual working memory capacity limitations: an amodal attentional resource that must be shared across remembered items; and the demands on context binding. We unconfounded these two factors by varying load with items drawn from the same stimulus category ("high demands on context binding") versus items drawn from different stimulus categories ("low demands on context binding"). The results provide evidence for the dissociability, and the neural bases, of these two theorized factors, and they specify that the functions of intraparietal sulcus may relate more strongly to the control of representations than to the general allocation of attention. Copyright © 2018 the authors 0270-6474/18/384357-10$15.00/0.

Artificial neural networks as quantum associative memory

NASA Astrophysics Data System (ADS)

Hamilton, Kathleen; Schrock, Jonathan; Imam, Neena; Humble, Travis

We present results related to the recall accuracy and capacity of Hopfield networks implemented on commercially available quantum annealers. The use of Hopfield networks and artificial neural networks as content-addressable memories offer robust storage and retrieval of classical information, however, implementation of these models using currently available quantum annealers faces several challenges: the limits of precision when setting synaptic weights, the effects of spurious spin-glass states and minor embedding of densely connected graphs into fixed-connectivity hardware. We consider neural networks which are less than fully-connected, and also consider neural networks which contain multiple sparsely connected clusters. We discuss the effect of weak edge dilution on the accuracy of memory recall, and discuss how the multiple clique structure affects the storage capacity. Our work focuses on storage of patterns which can be embedded into physical hardware containing n < 1000 qubits. This work was supported by the United States Department of Defense and used resources of the Computational Research and Development Programs as Oak Ridge National Laboratory under Contract No. DE-AC0500OR22725 with the U. S. Department of Energy.

Consciousness and working memory: Current trends and research perspectives.

PubMed

Velichkovsky, Boris B

2017-10-01

Working memory has long been thought to be closely related to consciousness. However, recent empirical studies show that unconscious content may be maintained within working memory and that complex cognitive computations may be performed on-line. This promotes research on the exact relationships between consciousness and working memory. Current evidence for working memory being a conscious as well as an unconscious process is reviewed. Consciousness is shown to be considered a subset of working memory by major current theories of working memory. Evidence for unconscious elements in working memory is shown to come from visual masking and attentional blink paradigms, and from the studies of implicit working memory. It is concluded that more research is needed to explicate the relationship between consciousness and working memory. Future research directions regarding the relationship between consciousness and working memory are discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

The Relationships of Working Memory, Secondary Memory, and General Fluid Intelligence: Working Memory is Special

PubMed Central

Shelton, Jill Talley; Elliott, Emily M.; Matthews, Russell A.; Hill, B. D.; Gouvier, Wm. Drew

2010-01-01

Recent efforts have been made to elucidate the commonly observed link between working memory and reasoning ability. The results have been inconsistent, with some work suggesting the emphasis placed on retrieval from secondary memory by working memory tests is the driving force behind this association (Mogle, Lovett, Stawski, & Sliwinski, 2008), while other research suggests retrieval from secondary memory is only partly responsible for the observed link between working memory and reasoning (Unsworth & Engle, 2006, 2007b). The present study investigates the relationship between processing speed, working memory, secondary memory, primary memory, and fluid intelligence. Although our findings show all constructs are significantly correlated with fluid intelligence, working memory, but not secondary memory, accounts for significant unique variance in fluid intelligence. Our data support predictions made by Unsworth and Engle, and suggest that the combined need for maintenance and retrieval processes present in working memory tests makes them “special” in their prediction of higher-order cognition. PMID:20438278

Working Memory From the Psychological and Neurosciences Perspectives: A Review.

PubMed

Chai, Wen Jia; Abd Hamid, Aini Ismafairus; Abdullah, Jafri Malin

2018-01-01

Since the concept of working memory was introduced over 50 years ago, different schools of thought have offered different definitions for working memory based on the various cognitive domains that it encompasses. The general consensus regarding working memory supports the idea that working memory is extensively involved in goal-directed behaviors in which information must be retained and manipulated to ensure successful task execution. Before the emergence of other competing models, the concept of working memory was described by the multicomponent working memory model proposed by Baddeley and Hitch. In the present article, the authors provide an overview of several working memory-relevant studies in order to harmonize the findings of working memory from the neurosciences and psychological standpoints, especially after citing evidence from past studies of healthy, aging, diseased, and/or lesioned brains. In particular, the theoretical framework behind working memory, in which the related domains that are considered to play a part in different frameworks (such as memory's capacity limit and temporary storage) are presented and discussed. From the neuroscience perspective, it has been established that working memory activates the fronto-parietal brain regions, including the prefrontal, cingulate, and parietal cortices. Recent studies have subsequently implicated the roles of subcortical regions (such as the midbrain and cerebellum) in working memory. Aging also appears to have modulatory effects on working memory; age interactions with emotion, caffeine and hormones appear to affect working memory performances at the neurobiological level. Moreover, working memory deficits are apparent in older individuals, who are susceptible to cognitive deterioration. Another younger population with working memory impairment consists of those with mental, developmental, and/or neurological disorders such as major depressive disorder and others. A less coherent and organized neural pattern has been consistently reported in these disadvantaged groups. Working memory of patients with traumatic brain injury was similarly affected and shown to have unusual neural activity (hyper- or hypoactivation) as a general observation. Decoding the underlying neural mechanisms of working memory helps support the current theoretical understandings concerning working memory, and at the same time provides insights into rehabilitation programs that target working memory impairments from neurophysiological or psychological aspects.

Interference and memory capacity limitations.

PubMed

Endress, Ansgar D; Szabó, Szilárd

2017-10-01

Working memory (WM) is thought to have a fixed and limited capacity. However, the origins of these capacity limitations are debated, and generally attributed to active, attentional processes. Here, we show that the existence of interference among items in memory mathematically guarantees fixed and limited capacity limits under very general conditions, irrespective of any processing assumptions. Assuming that interference (a) increases with the number of interfering items and (b) brings memory performance to chance levels for large numbers of interfering items, capacity limits are a simple function of the relative influence of memorization and interference. In contrast, we show that time-based memory limitations do not lead to fixed memory capacity limitations that are independent of the timing properties of an experiment. We show that interference can mimic both slot-like and continuous resource-like memory limitations, suggesting that these types of memory performance might not be as different as commonly believed. We speculate that slot-like WM limitations might arise from crowding-like phenomena in memory when participants have to retrieve items. Further, based on earlier research on parallel attention and enumeration, we suggest that crowding-like phenomena might be a common reason for the 3 major cognitive capacity limitations. As suggested by Miller (1956) and Cowan (2001), these capacity limitations might arise because of a common reason, even though they likely rely on distinct processes. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Practical proof of CP element based design for 14nm node and beyond

NASA Astrophysics Data System (ADS)

Maruyama, Takashi; Takita, Hiroshi; Ikeno, Rimon; Osawa, Morimi; Kojima, Yoshinori; Sugatani, Shinji; Hoshino, Hiromi; Hino, Toshio; Ito, Masaru; Iizuka, Tetsuya; Komatsu, Satoshi; Ikeda, Makoto; Asada, Kunihiro

2013-03-01

To realize HVM (High Volume Manufacturing) with CP (Character Projection) based EBDW, the shot count reduction is the essential key. All device circuits should be composed with predefined character parts and we call this methodology "CP element based design". In our previous work, we presented following three concepts [2]. 1) Memory: We reported the prospects of affordability for the CP-stencil resource. 2) Logic cell: We adopted a multi-cell clustering approach in the physical synthesis. 3) Random interconnect: We proposed an ultra-regular layout scheme using fixed size wiring tiles containing repeated tracks and cutting points at the tile edges. In this paper, we will report the experimental proofs in these methodologies. In full chip layout, CP stencil resource management is critical key. From the MCC-POC (Proof of Concept) result [1], we assumed total available CP stencil resource as 9000um2. We should manage to layout all circuit macros within this restriction. Especially the issues in assignment of CP-stencil resource for the memory macros are the most important as they consume considerable degree of resource because of the various line-ups such as 1RW-, 2RW-SRAMs, Resister Files and ROM which require several varieties of large size peripheral circuits. Furthermore the memory macros typically take large area of more than 40% of die area in the forefront logic LSI products so that the shot count increase impact is serious. To realize CP-stencil resource saving we had constructed automatic CP analyzing system. We developed two types of extraction mode of simple division by block and layout repeatability recognition. By properly controlling these models based upon each peripheral circuit characteristics, we could minimize the consumption of CP stencil resources. The estimation for 14nm technology node had been performed based on the analysis of practical memory compiler. The required resource for memory macro is proved to be affordable value which is 60% of full CP stencil resource and wafer level converted shot count is proved to be the level which meets 100WPH throughput. In logic cell design, circuit performance verification result after the cell clustering has been estimated. The cell clustering by the acknowledgment of physical distance proved to owe large penalty mainly in the wiring length. To reduce this design penalty, we proposed CP cell clustering by the acknowledgment of logical distance. For shot-count reduction of random interconnect area design, we proposed a more structural routing architecture which consists of the track exchange and the via position arrangement. Putting these design approaches together, we can design CP stencils to hit the target throughput within the area constraint. From the analysis for other macros such as analog, I/O, and DUMMY, it has proved that we don't need special CP design approach than legacy pattern matching CP extraction. From all these experimental results we get good prospects to the reality of full CP element based layout.

The Two Sides of Sensory–Cognitive Interactions: Effects of Age, Hearing Acuity, and Working Memory Span on Sentence Comprehension

PubMed Central

DeCaro, Renee; Peelle, Jonathan E.; Grossman, Murray; Wingfield, Arthur

2016-01-01

Reduced hearing acuity is among the most prevalent of chronic medical conditions among older adults. An experiment is reported in which comprehension of spoken sentences was tested for older adults with good hearing acuity or with a mild-to-moderate hearing loss, and young adults with age-normal hearing. Comprehension was measured by participants’ ability to determine the agent of an action in sentences that expressed this relation with a syntactically less complex subject-relative construction or a syntactically more complex object-relative construction. Agency determination was further challenged by inserting a prepositional phrase into sentences between the person performing an action and the action being performed. As a control, prepositional phrases of equivalent length were also inserted into sentences in a non-disruptive position. Effects on sentence comprehension of age, hearing acuity, prepositional phrase placement and sound level of stimulus presentations appeared only for comprehension of sentences with the more syntactically complex object-relative structures. Working memory as tested by reading span scores accounted for a significant amount of the variance in comprehension accuracy. Once working memory capacity and hearing acuity were taken into account, chronological age among the older adults contributed no further variance to comprehension accuracy. Results are discussed in terms of the positive and negative effects of sensory–cognitive interactions in comprehension of spoken sentences and lend support to a framework in which domain-general executive resources, notably verbal working memory, play a role in both linguistic and perceptual processing. PMID:26973557

The Nature of Individual Differences in Working Memory Capacity: Active Maintenance in Primary Memory and Controlled Search from Secondary Memory

ERIC Educational Resources Information Center

Unsworth, Nash; Engle, Randall W.

2007-01-01

Studies examining individual differences in working memory capacity have suggested that individuals with low working memory capacities demonstrate impaired performance on a variety of attention and memory tasks compared with individuals with high working memory capacities. This working memory limitation can be conceived of as arising from 2…

Impact of memory bottleneck on the performance of graphics processing units

NASA Astrophysics Data System (ADS)

Son, Dong Oh; Choi, Hong Jun; Kim, Jong Myon; Kim, Cheol Hong

2015-12-01

Recent graphics processing units (GPUs) can process general-purpose applications as well as graphics applications with the help of various user-friendly application programming interfaces (APIs) supported by GPU vendors. Unfortunately, utilizing the hardware resource in the GPU efficiently is a challenging problem, since the GPU architecture is totally different to the traditional CPU architecture. To solve this problem, many studies have focused on the techniques for improving the system performance using GPUs. In this work, we analyze the GPU performance varying GPU parameters such as the number of cores and clock frequency. According to our simulations, the GPU performance can be improved by 125.8% and 16.2% on average as the number of cores and clock frequency increase, respectively. However, the performance is saturated when memory bottleneck problems incur due to huge data requests to the memory. The performance of GPUs can be improved as the memory bottleneck is reduced by changing GPU parameters dynamically.

Event-Based Prospective Memory Is Resistant but Not Immune to Proactive Interference.

PubMed

Oates, Joyce M; Peynircioglu, Zehra F

2016-01-01

Recent evidence suggests that proactive interference (PI) does not hurt event-based prospective memory (ProM) the way it does retrospective memory (RetroM) (Oates, Peynircioglu, & Bates, 2015). We investigated this apparent resistance further. Introduction of a distractor task to ensure we were testing ProM rather than vigilance in Experiment 1 and tripling the number of lists to provide more opportunity for PI buildup in Experiment 2 still did not produce performance decrements. However, when the ProM task was combined with a RetroM task in Experiment 3, a comparable buildup and release was observed also in the ProM task. It appears that event based ProM is indeed somewhat resistant to PI, but this resistance can break down when the ProM task comprises the same stimuli as in an embedded RetroM task. We discuss the results using the ideas of cue overload and distinctiveness as well as shared attentional and working memory resources.

The contributions of handedness and working memory to episodic memory.

PubMed

Sahu, Aparna; Christman, Stephen D; Propper, Ruth E

2016-11-01

Past studies have independently shown associations of working memory and degree of handedness with episodic memory retrieval. The current study takes a step ahead by examining whether handedness and working memory independently predict episodic memory. In agreement with past studies, there was an inconsistent-handed advantage for episodic memory; however, this advantage was absent for working memory tasks. Furthermore, regression analyses showed handedness, and complex working memory predicted episodic memory performance at different times. Results are discussed in light of theories of episodic memory and hemispheric interaction.

Working Memory From the Psychological and Neurosciences Perspectives: A Review

PubMed Central

Chai, Wen Jia; Abd Hamid, Aini Ismafairus; Abdullah, Jafri Malin

2018-01-01

Since the concept of working memory was introduced over 50 years ago, different schools of thought have offered different definitions for working memory based on the various cognitive domains that it encompasses. The general consensus regarding working memory supports the idea that working memory is extensively involved in goal-directed behaviors in which information must be retained and manipulated to ensure successful task execution. Before the emergence of other competing models, the concept of working memory was described by the multicomponent working memory model proposed by Baddeley and Hitch. In the present article, the authors provide an overview of several working memory-relevant studies in order to harmonize the findings of working memory from the neurosciences and psychological standpoints, especially after citing evidence from past studies of healthy, aging, diseased, and/or lesioned brains. In particular, the theoretical framework behind working memory, in which the related domains that are considered to play a part in different frameworks (such as memory’s capacity limit and temporary storage) are presented and discussed. From the neuroscience perspective, it has been established that working memory activates the fronto-parietal brain regions, including the prefrontal, cingulate, and parietal cortices. Recent studies have subsequently implicated the roles of subcortical regions (such as the midbrain and cerebellum) in working memory. Aging also appears to have modulatory effects on working memory; age interactions with emotion, caffeine and hormones appear to affect working memory performances at the neurobiological level. Moreover, working memory deficits are apparent in older individuals, who are susceptible to cognitive deterioration. Another younger population with working memory impairment consists of those with mental, developmental, and/or neurological disorders such as major depressive disorder and others. A less coherent and organized neural pattern has been consistently reported in these disadvantaged groups. Working memory of patients with traumatic brain injury was similarly affected and shown to have unusual neural activity (hyper- or hypoactivation) as a general observation. Decoding the underlying neural mechanisms of working memory helps support the current theoretical understandings concerning working memory, and at the same time provides insights into rehabilitation programs that target working memory impairments from neurophysiological or psychological aspects. PMID:29636715

Coaching positively influences the effects of working memory training on visual working memory as well as mathematical ability.

PubMed

Nelwan, Michel; Vissers, Constance; Kroesbergen, Evelyn H

2018-05-01

The goal of the present study was to test whether the amount of coaching influenced the results of working memory training on both visual and verbal working memory. Additionally, the effects of the working memory training on the amount of progress after specific training in mathematics were evaluated. In this study, 23 children between 9 and 12 years of age with both attentional and mathematical difficulties participated in a working memory training program with a high amount of coaching, while another 25 children received no working memory training. Results of these groups were compared to 21 children who completed the training with a lower amount of coaching. The quality of working memory, as well as mathematic skills, were measured three times using untrained transfer tasks. Bayesian statistics were used to test informative hypotheses. After receiving working memory training, the highly coached group performed better than the group that received less coaching on visual working memory and mathematics, but not on verbal working memory. The highly coached group retained their advantage in mathematics, even though the effect on visual working memory decreased. However, no added effect of working memory training was found on the learning curve during mathematical training. Moreover, the less-coached group was outperformed by the group that did not receive working memory training, both in visual working memory and mathematics. These results suggest that motivation and proper coaching might be crucial for ensuring compliance and effects of working memory training, and that far transfer might be possible. Copyright © 2018 Elsevier Ltd. All rights reserved.

Introduction to the Special Issue on Visual Working Memory

PubMed Central

Wolfe, Jeremy M

2014-01-01

Objects are not represented individually in visual working memory (VWM), but in relation to the contextual information provided by other memorized objects. We studied whether the contextual information provided by the spatial configuration of all memorized objects is viewpoint-dependent. We ran two experiments asking participants to detect changes in locations between memory and probe for one object highlighted in the probe image. We manipulated the changes in viewpoint between memory and probe (Exp. 1: 0°, 30°, 60°; Exp. 2: 0°, 60°), as well as the spatial configuration visible in the probe image (Exp. 1: full configuration, partial configuration; Exp. 2: full configuration, no configuration). Location change detection was higher with the full spatial configuration than with the partial configuration or with no spatial configuration at viewpoint changes of 0°, thus replicating previous findings on the nonindependent representations of individual objects in VWM. Most importantly, the effect of spatial configurations decreased with increasing viewpoint changes, suggesting a viewpoint-dependent representation of contextual information in VWM. We discuss these findings within the context of this special issue, in particular whether research performed within the slots-versus-resources debate and research on the effects of contextual information might focus on two different storage systems within VWM. PMID:25341647

SPARC: Demonstrate burst-buffer-based checkpoint/restart on ATS-1.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oldfield, Ron A.; Ulmer, Craig D.; Widener, Patrick

Recent high-performance computing (HPC) platforms such as the Trinity Advanced Technology System (ATS-1) feature burst buffer resources that can have a dramatic impact on an application’s I/O performance. While these non-volatile memory (NVM) resources provide a new tier in the storage hierarchy, developers must find the right way to incorporate the technology into their applications in order to reap the benefits. Similar to other laboratories, Sandia is actively investigating ways in which these resources can be incorporated into our existing libraries and workflows without burdening our application developers with excessive, platform-specific details. This FY18Q1 milestone summaries our progress in adaptingmore » the Sandia Parallel Aerodynamics and Reentry Code (SPARC) in Sandia’s ATDM program to leverage Trinity’s burst buffers for checkpoint/restart operations. We investigated four different approaches with varying tradeoffs in this work: (1) simply updating job script to use stage-in/stage out burst buffer directives, (2) modifying SPARC to use LANL’s hierarchical I/O (HIO) library to store/retrieve checkpoints, (3) updating Sandia’s IOSS library to incorporate the burst buffer in all meshing I/O operations, and (4) modifying SPARC to use our Kelpie distributed memory library to store/retrieve checkpoints. Team members were successful in generating initial implementation for all four approaches, but were unable to obtain performance numbers in time for this report (reasons: initial problem sizes were not large enough to stress I/O, and SPARC refactor will require changes to our code). When we presented our work to the SPARC team, they expressed the most interest in the second and third approaches. The HIO work was favored because it is lightweight, unobtrusive, and should be portable to ATS-2. The IOSS work is seen as a long-term solution, and is favored because all I/O work (including checkpoints) can be deferred to a single library.« less

Approach motivation and cognitive resources combine to influence memory for positive emotional stimuli.

PubMed

Crowell, Adrienne; Schmeichel, Brandon J

2016-01-01

Inspired by the elaborated intrusion theory of desire, the current research tested the hypothesis that persons higher in trait approach motivation process positive stimuli deeply, which enhances memory for them. Ninety-four undergraduates completed a measure of trait approach motivation, viewed positive or negative image slideshows in the presence or absence of a cognitive load, and one week later completed an image memory test. Higher trait approach motivation predicted better memory for the positive slideshow, but this memory boost disappeared under cognitive load. Approach motivation did not influence memory for the negative slideshow. The current findings support the idea that individuals higher in approach motivation spontaneously devote limited resources to processing positive stimuli.

Can verbal working memory training improve reading?

PubMed

Banales, Erin; Kohnen, Saskia; McArthur, Genevieve

2015-01-01

The aim of the current study was to determine whether poor verbal working memory is associated with poor word reading accuracy because the former causes the latter, or the latter causes the former. To this end, we tested whether (a) verbal working memory training improves poor verbal working memory or poor word reading accuracy, and whether (b) reading training improves poor reading accuracy or verbal working memory in a case series of four children with poor word reading accuracy and verbal working memory. Each child completed 8 weeks of verbal working memory training and 8 weeks of reading training. Verbal working memory training improved verbal working memory in two of the four children, but did not improve their reading accuracy. Similarly, reading training improved word reading accuracy in all children, but did not improve their verbal working memory. These results suggest that the causal links between verbal working memory and reading accuracy may not be as direct as has been assumed.

The Effects of Age of Immersion and Working Memory on Second Language Processing of Island Constraints: An Eye-Movement Study

ERIC Educational Resources Information Center

Jung, Sehoon

2017-01-01

One of the central questions in recent second language processing research is whether the types of parsing heuristics and linguistic resources adult L2 learners compute during online processing are qualitatively similar or different from those used by native speakers of the target language. While the current L2 processing literature provides…

A bill to provide for an extension of the legislative authority of the Adams Memorial Foundation to establish a commemorative work in honor of former President John Adams and his legacy.

THOMAS, 113th Congress

Sen. Markey, Edward J. [D-MA

2013-12-19

Senate - 07/23/2014 Committee on Energy and Natural Resources Senate Subcommittee on National Parks. Hearings held. With printed Hearing: S.Hrg. 113-493. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

Cognitive Benefits of Last Night's Sleep: Daily Variations in Children's Sleep Behavior Are Related to Working Memory Fluctuations

ERIC Educational Resources Information Center

Könen, Tanja; Dirk, Judith; Schmiedek, Florian

2015-01-01

Background: Recent studies have suggested substantial fluctuations of cognitive performance in adults both across and within days, but very little is known about such fluctuations in children. Children's sleep behavior might have an important influence on their daily cognitive resources, but so far this has not been investigated in terms of…

Visual working memory buffers information retrieved from visual long-term memory.

PubMed

Fukuda, Keisuke; Woodman, Geoffrey F

2017-05-16

Human memory is thought to consist of long-term storage and short-term storage mechanisms, the latter known as working memory. Although it has long been assumed that information retrieved from long-term memory is represented in working memory, we lack neural evidence for this and need neural measures that allow us to watch this retrieval into working memory unfold with high temporal resolution. Here, we show that human electrophysiology can be used to track information as it is brought back into working memory during retrieval from long-term memory. Specifically, we found that the retrieval of information from long-term memory was limited to just a few simple objects' worth of information at once, and elicited a pattern of neurophysiological activity similar to that observed when people encode new information into working memory. Our findings suggest that working memory is where information is buffered when being retrieved from long-term memory and reconcile current theories of memory retrieval with classic notions about the memory mechanisms involved.

Visual working memory buffers information retrieved from visual long-term memory

PubMed Central

Fukuda, Keisuke; Woodman, Geoffrey F.

2017-01-01

Human memory is thought to consist of long-term storage and short-term storage mechanisms, the latter known as working memory. Although it has long been assumed that information retrieved from long-term memory is represented in working memory, we lack neural evidence for this and need neural measures that allow us to watch this retrieval into working memory unfold with high temporal resolution. Here, we show that human electrophysiology can be used to track information as it is brought back into working memory during retrieval from long-term memory. Specifically, we found that the retrieval of information from long-term memory was limited to just a few simple objects’ worth of information at once, and elicited a pattern of neurophysiological activity similar to that observed when people encode new information into working memory. Our findings suggest that working memory is where information is buffered when being retrieved from long-term memory and reconcile current theories of memory retrieval with classic notions about the memory mechanisms involved. PMID:28461479

Working and strategic memory deficits in schizophrenia

NASA Technical Reports Server (NTRS)

Stone, M.; Gabrieli, J. D.; Stebbins, G. T.; Sullivan, E. V.

1998-01-01

Working memory and its contribution to performance on strategic memory tests in schizophrenia were studied. Patients (n = 18) and control participants (n = 15), all men, received tests of immediate memory (forward digit span), working memory (listening, computation, and backward digit span), and long-term strategic (free recall, temporal order, and self-ordered pointing) and nonstrategic (recognition) memory. Schizophrenia patients performed worse on all tests. Education, verbal intelligence, and immediate memory capacity did not account for deficits in working memory in schizophrenia patients. Reduced working memory capacity accounted for group differences in strategic memory but not in recognition memory. Working memory impairment may be central to the profile of impaired cognitive performance in schizophrenia and is consistent with hypothesized frontal lobe dysfunction associated with this disease. Additional medial-temporal dysfunction may account for the recognition memory deficit.

The efficiency of multimedia learning into old age.

PubMed

Van Gerven, Pascal W M; Paas, Fred; Van Merriënboer, Jeroen J G; Hendriks, Maaike; Schmidt, Henk G

2003-12-01

On the basis of a multimodal model of working memory, cognitive load theory predicts that a multimedia-based instructional format leads to a better acquisition of complex subject matter than a purely visual instructional format. This study investigated the extent to which age and instructional format had an impact on training efficiency among both young and old adults. It was hypothesised that studying worked examples that are presented as a narrated animation (multimedia condition) is a more efficient means of complex skill training than studying visually presented worked examples (unimodal condition) and solving conventional problems. Furthermore, it was hypothesised that multimedia-based worked examples are especially helpful for elderly learners, who have to deal with a general decline of working-memory resources, because they address both mode-specific working-memory stores. The sample consisted of 60 young (mean age = 15.98 years) and 60 old adults (mean age = 64.48 years). Participants of both age groups were trained in either a conventional, a unimodal, or a multimedia condition. Subsequently, they had to solve a series of test problems. Dependent variables were perceived cognitive load during the training, performance on the test, and efficiency in terms of the ratio between these two variables. Results showed that for both age groups multimedia-based worked examples were more efficient than the other training formats in that less cognitive load led to at least an equal performance level. Although no difference in the beneficial effect of multimedia learning was found between the age groups, multimedia-based instructions seem promising for the elderly.

Memory systems interaction in the pigeon: working and reference memory.

PubMed

Roberts, William A; Strang, Caroline; Macpherson, Krista

2015-04-01

Pigeons' performance on a working memory task, symbolic delayed matching-to-sample, was used to examine the interaction between working memory and reference memory. Reference memory was established by training pigeons to discriminate between the comparison cues used in delayed matching as S+ and S- stimuli. Delayed matching retention tests then measured accuracy when working and reference memory were congruent and incongruent. In 4 experiments, it was shown that the interaction between working and reference memory is reciprocal: Strengthening either type of memory leads to a decrease in the influence of the other type of memory. A process dissociation procedure analysis of the data from Experiment 4 showed independence of working and reference memory, and a model of working memory and reference memory interaction was shown to predict the findings reported in the 4 experiments. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

Interactions Between Modality of Working Memory Load and Perceptual Load in Distractor Processing.

PubMed

Koshino, Hideya; Olid, Pilar

2015-01-01

The present study investigated interactions between working memory load and perceptual load. The load theory (Lavie, Hirst, de Fockert, & Viding, 2004 ) claims that perceptual load decreases distractor interference, whereas working memory load increases interference. However, recent studies showed that effects of working memory might depend on the relationship between modalities of working memory and task stimuli. Here, we examined whether the relationship between working memory load and perceptual load would remain the same across modalities. The results of Experiment 1 showed that verbal working memory load did not affect a compatibility effect for low perceptual load, whereas it increased the compatibility effect for high perceptual load. In Experiment 2, the compatibility effect remained the same regardless of visual working memory load. These results suggest that the effects of working memory load and perceptual load depend on the relationship between the modalities of working memory and stimuli.

Working-memory performance is related to spatial breadth of attention.

PubMed

Kreitz, Carina; Furley, Philip; Memmert, Daniel; Simons, Daniel J

2015-11-01

Working memory and attention are closely related constructs. Models of working memory often incorporate an attention component, and some even equate working memory and attentional control. Although some attention-related processes, including inhibitory control of response conflict and interference resolution, are strongly associated with working memory, for other aspects of attention the link is less clear. We examined the association between working-memory performance and attentional breadth, the ability to spread attention spatially. If the link between attention and working memory is broader than inhibitory and interference resolution processes, then working-memory performance might also be associated with other attentional abilities, including attentional breadth. We tested 123 participants on a variety of working-memory and attentional-breadth measures, finding a strong correlation between performances on these two types of tasks. This finding demonstrates that the link between working memory and attention extends beyond inhibitory processes.

Integrating information about location and value of resources by white-faced saki monkeys (Pithecia pithecia).

PubMed

Cunningham, Elena; Janson, Charles

2007-07-01

Most studies of spatial memory in primates focus on species that inhabit large home ranges and have dispersed, patchy resources. Researchers assume that primates use memory to minimize distances traveled between resources. We investigated the use of spatial memory in a group of six white-faced sakis (Pithecia pithecia) on 12.8-ha Round Island, Guri Lake, Venezuela during a period of fruit abundance. The sakis' movements were analyzed with logistic regressions, a predictive computer model and a computer model that simulates movements. We considered all the resources available to the sakis and compared observed distances to predicted distances from a computer model for foragers who know nothing about the location of resources. Surprisingly, the observed distances were four times greater than the predicted distances, suggesting that the sakis passed by a majority of the available fruit trees without feeding. The odds of visiting a food tree, however, were significantly increased if the tree had been visited in the previous 3 days and had more than 100 fruit. The sakis' preferred resources were highly productive fruit trees, Capparis trees, and trees with water holes. They traveled efficiently to these sites. The sakis choice of feeding sites indicate that they combined knowledge acquired by repeatedly traveling through their home range with 'what' and 'where' information gained from individual visits to resources. Although the sakis' foraging choices increased the distance they traveled overall, choosing more valued sites allowed the group to minimize intra-group feeding competition, maintain intergroup dominance over important resources, and monitor the state of resources throughout their home range. The sakis' foraging decisions appear to have used spatial memory, elements of episodic-like memory and social and nutritional considerations.

Aging and the intrusion superiority effect in visuo-spatial working memory.

PubMed

Cornoldi, Cesare; Bassani, Chiara; Berto, Rita; Mammarella, Nicola

2007-01-01

This study investigated the active component of visuo-spatial working memory (VSWM) in younger and older adults testing the hypotheses that elderly individuals have a poorer performance than younger ones and that errors in active VSWM tasks depend, at least partially, on difficulties in avoiding intrusions (i.e., avoiding already activated information). In two experiments, participants were presented with sequences of matrices on which three positions were pointed out sequentially: their task was to process all the positions but indicate only the final position of each sequence. Results showed a poorer performance in the elderly compared to the younger group and a higher number of intrusion (errors due to activated but irrelevant positions) rather than invention (errors consisting of pointing out a position never indicated by the experiementer) errors. The number of errors increased when a concurrent task was introduced (Experiment 1) and it was affected by different patterns of matrices (Experiment 2). In general, results show that elderly people have an impaired VSWM and produce a large number of errors due to inhibition failures. However, both the younger and the older adults' visuo-spatial working memory was affected by the presence of activated irrelevant information, the reduction of the available resources, and task constraints.

Working memory load impairs the evaluation of behavioral errors in the medial frontal cortex.

PubMed

Maier, Martin E; Steinhauser, Marco

2017-10-01

Early error monitoring in the medial frontal cortex enables error detection and the evaluation of error significance, which helps prioritize adaptive control. This ability has been assumed to be independent from central capacity, a limited pool of resources assumed to be involved in cognitive control. The present study investigated whether error evaluation depends on central capacity by measuring the error-related negativity (Ne/ERN) in a flanker paradigm while working memory load was varied on two levels. We used a four-choice flanker paradigm in which participants had to classify targets while ignoring flankers. Errors could be due to responding either to the flankers (flanker errors) or to none of the stimulus elements (nonflanker errors). With low load, the Ne/ERN was larger for flanker errors than for nonflanker errors-an effect that has previously been interpreted as reflecting differential significance of these error types. With high load, no such effect of error type on the Ne/ERN was observable. Our findings suggest that working memory load does not impair the generation of an Ne/ERN per se but rather impairs the evaluation of error significance. They demonstrate that error monitoring is composed of capacity-dependent and capacity-independent mechanisms. © 2017 Society for Psychophysiological Research.

Selective visual processing across competition episodes: a theory of task-driven visual attention and working memory

PubMed Central

Schneider, Werner X.

2013-01-01

The goal of this review is to introduce a theory of task-driven visual attention and working memory (TRAM). Based on a specific biased competition model, the ‘theory of visual attention’ (TVA) and its neural interpretation (NTVA), TRAM introduces the following assumption. First, selective visual processing over time is structured in competition episodes. Within an episode, that is, during its first two phases, a limited number of proto-objects are competitively encoded—modulated by the current task—in activation-based visual working memory (VWM). In processing phase 3, relevant VWM objects are transferred via a short-term consolidation into passive VWM. Second, each time attentional priorities change (e.g. after an eye movement), a new competition episode is initiated. Third, if a phase 3 VWM process (e.g. short-term consolidation) is not finished, whereas a new episode is called, a protective maintenance process allows its completion. After a VWM object change, its protective maintenance process is followed by an encapsulation of the VWM object causing attentional resource costs in trailing competition episodes. Viewed from this perspective, a new explanation of key findings of the attentional blink will be offered. Finally, a new suggestion will be made as to how VWM items might interact with visual search processes. PMID:24018722

Does Working Memory Enhance or Interfere With Speech Fluency in Adults Who Do and Do Not Stutter? Evidence From a Dual-Task Paradigm.

PubMed

Eichorn, Naomi; Marton, Klara; Schwartz, Richard G; Melara, Robert D; Pirutinsky, Steven

2016-06-01

The present study examined whether engaging working memory in a secondary task benefits speech fluency. Effects of dual-task conditions on speech fluency, rate, and errors were examined with respect to predictions derived from three related theoretical accounts of disfluencies. Nineteen adults who stutter and twenty adults who do not stutter participated in the study. All participants completed 2 baseline tasks: a continuous-speaking task and a working-memory (WM) task involving manipulations of domain, load, and interstimulus interval. In the dual-task portion of the experiment, participants simultaneously performed the speaking task with each unique combination of WM conditions. All speakers showed similar fluency benefits and decrements in WM accuracy as a result of dual-task conditions. Fluency effects were specific to atypical forms of disfluency and were comparable across WM-task manipulations. Changes in fluency were accompanied by reductions in speaking rate but not by corresponding changes in overt errors. Findings suggest that WM contributes to disfluencies regardless of stuttering status and that engaging WM resources while speaking enhances fluency. Further research is needed to verify the cognitive mechanism involved in this effect and to determine how these findings can best inform clinical intervention.

Modulation of working memory load distinguishes individuals with and without balance impairments following mild traumatic brain injury.

PubMed

Woytowicz, Elizabeth J; Sours, Chandler; Gullapalli, Rao P; Rosenberg, Joseph; Westlake, Kelly P

2018-01-01

Balance and gait deficits can persist after mild traumatic brain injury (TBI), yet an understanding of the underlying neural mechanism remains limited. The purpose of this study was to investigate differences in attention network modulation in patients with and without balance impairments 2-8 weeks following mild TBI. Using functional magnetic resonance imaging, we compared activity and functional connectivity of cognitive brain regions of the default mode, central-executive and salience networks during a 2-back working memory task in participants with mild TBI and balance impairments (n = 7, age 47 ± 15 years) or no balance impairments (n = 7, age 47 ± 15 years). We first identified greater activation in the lateral occipital cortex in the balance impaired group. Second, we observed stronger connectivity of left pre-supplementary motor cortex in the balance impaired group during the working memory task, which was related to decreased activation of regions within the salience and central executive networks and greater suppression of the default mode network. Results suggest a link between impaired balance and modulation of cognitive resources in patients in mTBI. Findings also highlight the potential importance of moving beyond traditional balance assessments towards an integrative assessment of cognition and balance in this population.

Cultural differences in complex addition: efficient Chinese versus adaptive Belgians and Canadians.

PubMed

Imbo, Ineke; LeFevre, Jo-Anne

2009-11-01

In the present study, the authors tested the effects of working-memory load on math problem solving in 3 different cultures: Flemish-speaking Belgians, English-speaking Canadians, and Chinese-speaking Chinese currently living in Canada. Participants solved complex addition problems (e.g., 58 + 76) in no-load and working-memory load conditions, in which either the central executive or the phonological loop was loaded. The authors used the choice/no-choice method to obtain unbiased measures of strategy selection and strategy efficiency. The Chinese participants were faster than the Belgians, who were faster and more accurate than the Canadians. The Chinese also required fewer working-memory resources than did the Belgians and Canadians. However, the Chinese chose less adaptively from the available strategies than did the Belgians and Canadians. These cultural differences in math problem solving are likely the result of different instructional approaches during elementary school (practice and training in Asian countries vs. exploration and flexibility in non-Asian countries), differences in the number language, and informal cultural norms and standards. The relevance of being adaptive is discussed as well as the implications of the results in regards to the strategy choice and discovery simulation model of strategy selection (J. Shrager & R. S. Siegler, 1998).

Effects of Motion in the Far Peripheral Visual Field on Cognitive Test Performance and Cognitive Load.

PubMed

Bevilacqua, Andy; Paas, Fred; Krigbaum, Genomary

2016-04-01

Cognitive load theory posits that limited attention is in actuality a limitation in working memory resources. The load theory of selective attention and cognitive control sees the interplay between attention and awareness as separate modifying functions that act on working memory. Reconciling the theoretical differences in these two theories has important implications for learning. Thirty-nine adult participants performed a cognitively demanding test, with and without movement in the far peripheral field. Although the results for movement effects on cognitive load in this experiment were not statistically significant, men spent less time on the cognitive test in the peripheral movement condition than in the conditions without peripheral movement. No such difference was found for women. The implications of these results and recommendations for future research that extends the present study are presented. © The Author(s) 2016.

Effect of cognitive load on working memory forgetting in aging.

PubMed

Baumans, Christine; Adam, Stephane; Seron, Xavier

2012-01-01

Functional approaches to working memory (WM) have been proposed recently to better investigate "maintenance" and "processing" mechanisms. The cognitive load (CL) hypothesis presented in the "Time-Based Resource-Sharing" model (Barrouillet & Camos, 2007) suggests that forgetting from WM (maintenance) can be investigated by varying the presentation rate and processing speed (processing). In this study, young and elderly participants were compared on WM tasks in which the difference in processing speed was controlled by CL manipulations. Two main results were found. First, when time constraints (CL) were matched for the two groups, no aging effect was observed. Second, whereas a large variation in CL affected WM performance, a small CL manipulation had no effect on the elderly. This suggests that WM forgetting cannot be completely accounted for by the CL hypothesis. Rather, it highlights the need to explore restoration times in particular, and the nature of the refreshment mechanisms within maintenance.

Common neural substrates for visual working memory and attention.

PubMed

Mayer, Jutta S; Bittner, Robert A; Nikolić, Danko; Bledowski, Christoph; Goebel, Rainer; Linden, David E J

2007-06-01

Humans are severely limited in their ability to memorize visual information over short periods of time. Selective attention has been implicated as a limiting factor. Here we used functional magnetic resonance imaging to test the hypothesis that this limitation is due to common neural resources shared by visual working memory (WM) and selective attention. We combined visual search and delayed discrimination of complex objects and independently modulated the demands on selective attention and WM encoding. Participants were presented with a search array and performed easy or difficult visual search in order to encode one or three complex objects into visual WM. Overlapping activation for attention-demanding visual search and WM encoding was observed in distributed posterior and frontal regions. In the right prefrontal cortex and bilateral insula blood oxygen-level-dependent activation additively increased with increased WM load and attentional demand. Conversely, several visual, parietal and premotor areas showed overlapping activation for the two task components and were severely reduced in their WM load response under the condition with high attentional demand. Regions in the left prefrontal cortex were selectively responsive to WM load. Areas selectively responsive to high attentional demand were found within the right prefrontal and bilateral occipital cortex. These results indicate that encoding into visual WM and visual selective attention require to a high degree access to common neural resources. We propose that competition for resources shared by visual attention and WM encoding can limit processing capabilities in distributed posterior brain regions.

Working Memory in the Classroom: An Inside Look at the Central Executive.

PubMed

Barker, Lauren A

2016-01-01

This article provides a review of working memory and its application to educational settings. A discussion of the varying definitions of working memory is presented. Special attention is given to the various multidisciplinary professionals who work with students with working memory deficits, and their unique understanding of the construct. Definitions and theories of working memory are briefly summarized and provide the foundation for understanding practical applications of working memory to assessment and intervention. Although definitions and models of working memory abound, there is limited consensus regarding universally accepted definitions and models. Current research indicates that developing new models of working memory may be an appropriate paradigm shift at this time. The integration of individual practitioner's knowledge regarding academic achievement, working memory and processing speed could provide a foundation for the future development of new working memory models. Future directions for research should aim to explain how tasks and behaviors are supported by the substrates of the cortico-striatal and the cerebro-cerebellar systems. Translation of neurobiological information into educational contexts will be helpful to inform all practitioners' knowledge of working memory constructs. It will also allow for universally accepted definitions and models of working memory to arise and facilitate more effective collaboration between disciplines working in educational setting.

Attractor neural networks with resource-efficient synaptic connectivity

NASA Astrophysics Data System (ADS)

Pehlevan, Cengiz; Sengupta, Anirvan

Memories are thought to be stored in the attractor states of recurrent neural networks. Here we explore how resource constraints interplay with memory storage function to shape synaptic connectivity of attractor networks. We propose that given a set of memories, in the form of population activity patterns, the neural circuit choses a synaptic connectivity configuration that minimizes a resource usage cost. We argue that the total synaptic weight (l1-norm) in the network measures the resource cost because synaptic weight is correlated with synaptic volume, which is a limited resource, and is proportional to neurotransmitter release and post-synaptic current, both of which cost energy. Using numerical simulations and replica theory, we characterize optimal connectivity profiles in resource-efficient attractor networks. Our theory explains several experimental observations on cortical connectivity profiles, 1) connectivity is sparse, because synapses are costly, 2) bidirectional connections are overrepresented and 3) are stronger, because attractor states need strong recurrence.

Examining factors involved in stress-related working memory impairments: Independent or conditional effects?

PubMed

Banks, Jonathan B; Tartar, Jaime L; Tamayo, Brittney A

2015-12-01

A large and growing body of research demonstrates the impact of psychological stress on working memory. However, the typical study approach tests the effects of a single biological or psychological factor on changes in working memory. The current study attempted to move beyond the standard single-factor assessment by examining the impact of 2 possible factors in stress-related working memory impairments. To this end, 60 participants completed a working memory task before and after either a psychological stressor writing task or a control writing task and completed measures of both cortisol and mind wandering. We also included a measure of state anxiety to examine the direct and indirect effect on working memory. We found that mind wandering mediated the relationship between state anxiety and working memory at the baseline measurement. This indirect relationship was moderated by cortisol, such that the impact of mind wandering on working memory increased as cortisol levels increased. No overall working memory impairment was observed following the stress manipulation, but increases in state anxiety and mind wandering were observed. State anxiety and mind wandering independently mediated the relationship between change in working memory and threat perception. The indirect paths resulted in opposing effects on working memory. Combined, the findings from this study suggest that cortisol enhances the impact of mind wandering on working memory, that state anxiety may not always result in stress-related working memory impairments, and that high working memory performance can protect against mind wandering. (c) 2015 APA, all rights reserved).

Transfer after Working Memory Updating Training

PubMed Central

Waris, Otto; Soveri, Anna; Laine, Matti

2015-01-01

During the past decade, working memory training has attracted much interest. However, the training outcomes have varied between studies and methodological problems have hampered the interpretation of results. The current study examined transfer after working memory updating training by employing an extensive battery of pre-post cognitive measures with a focus on near transfer. Thirty-one healthy Finnish young adults were randomized into either a working memory training group or an active control group. The working memory training group practiced with three working memory tasks, while the control group trained with three commercial computer games with a low working memory load. The participants trained thrice a week for five weeks, with one training session lasting about 45 minutes. Compared to the control group, the working memory training group showed strongest transfer to an n-back task, followed by working memory updating, which in turn was followed by active working memory capacity. Our results support the view that working memory training produces near transfer effects, and that the degree of transfer depends on the cognitive overlap between the training and transfer measures. PMID:26406319

Transfer after Working Memory Updating Training.

PubMed

Waris, Otto; Soveri, Anna; Laine, Matti

2015-01-01

During the past decade, working memory training has attracted much interest. However, the training outcomes have varied between studies and methodological problems have hampered the interpretation of results. The current study examined transfer after working memory updating training by employing an extensive battery of pre-post cognitive measures with a focus on near transfer. Thirty-one healthy Finnish young adults were randomized into either a working memory training group or an active control group. The working memory training group practiced with three working memory tasks, while the control group trained with three commercial computer games with a low working memory load. The participants trained thrice a week for five weeks, with one training session lasting about 45 minutes. Compared to the control group, the working memory training group showed strongest transfer to an n-back task, followed by working memory updating, which in turn was followed by active working memory capacity. Our results support the view that working memory training produces near transfer effects, and that the degree of transfer depends on the cognitive overlap between the training and transfer measures.

Seeing the talker's face supports executive processing of speech in steady state noise.

PubMed

Mishra, Sushmit; Lunner, Thomas; Stenfelt, Stefan; Rönnberg, Jerker; Rudner, Mary

2013-01-01

Listening to speech in noise depletes cognitive resources, affecting speech processing. The present study investigated how remaining resources or cognitive spare capacity (CSC) can be deployed by young adults with normal hearing. We administered a test of CSC (CSCT; Mishra et al., 2013) along with a battery of established cognitive tests to 20 participants with normal hearing. In the CSCT, lists of two-digit numbers were presented with and without visual cues in quiet, as well as in steady-state and speech-like noise at a high intelligibility level. In low load conditions, two numbers were recalled according to instructions inducing executive processing (updating, inhibition) and in high load conditions the participants were additionally instructed to recall one extra number, which was the always the first item in the list. In line with previous findings, results showed that CSC was sensitive to memory load and executive function but generally not related to working memory capacity (WMC). Furthermore, CSCT scores in quiet were lowered by visual cues, probably due to distraction. In steady-state noise, the presence of visual cues improved CSCT scores, probably by enabling better encoding. Contrary to our expectation, CSCT performance was disrupted more in steady-state than speech-like noise, although only without visual cues, possibly because selective attention could be used to ignore the speech-like background and provide an enriched representation of target items in working memory similar to that obtained in quiet. This interpretation is supported by a consistent association between CSCT scores and updating skills.

The Effects of Restricted Peripheral Field-of-View on Spatial Learning while Navigating.

PubMed

Barhorst-Cates, Erica M; Rand, Kristina M; Creem-Regehr, Sarah H

2016-01-01

Recent work with simulated reductions in visual acuity and contrast sensitivity has found decrements in survey spatial learning as well as increased attentional demands when navigating, compared to performance with normal vision. Given these findings, and previous work showing that peripheral field loss has been associated with impaired mobility and spatial memory for room-sized spaces, we investigated the role of peripheral vision during navigation using a large-scale spatial learning paradigm. First, we aimed to establish the magnitude of spatial memory errors at different levels of field restriction. Second, we tested the hypothesis that navigation under these different levels of restriction would use additional attentional resources. Normally sighted participants walked on novel real-world paths wearing goggles that restricted the field-of-view (FOV) to severe (15°, 10°, 4°, or 0°) or mild angles (60°) and then pointed to remembered target locations using a verbal reporting measure. They completed a concurrent auditory reaction time task throughout each path to measure cognitive load. Only the most severe restrictions (4° and blindfolded) showed impairment in pointing error compared to the mild restriction (within-subjects). The 10° and 4° conditions also showed an increase in reaction time on the secondary attention task, suggesting that navigating with these extreme peripheral field restrictions demands the use of limited cognitive resources. This comparison of different levels of field restriction suggests that although peripheral field loss requires the actor to use more attentional resources while navigating starting at a less extreme level (10°), spatial memory is not negatively affected until the restriction is very severe (4°). These results have implications for understanding of the mechanisms underlying spatial learning during navigation and the approaches that may be taken to develop assistance for navigation with visual impairment.

The Relationships of Working Memory, Secondary Memory, and General Fluid Intelligence: Working Memory Is Special

ERIC Educational Resources Information Center

Shelton, Jill Talley; Elliott, Emily M.; Matthews, Russell A.; Hill, B. D.; Gouvier, Wm. Drew

2010-01-01

Recent efforts have been made to elucidate the commonly observed link between working memory and reasoning ability. The results have been inconsistent, with some work suggesting that the emphasis placed on retrieval from secondary memory by working memory tests is the driving force behind this association (Mogle, Lovett, Stawski, & Sliwinski,…

Nonvolatile reconfigurable sequential logic in a HfO2 resistive random access memory array.

PubMed

Zhou, Ya-Xiong; Li, Yi; Su, Yu-Ting; Wang, Zhuo-Rui; Shih, Ling-Yi; Chang, Ting-Chang; Chang, Kuan-Chang; Long, Shi-Bing; Sze, Simon M; Miao, Xiang-Shui

2017-05-25

Resistive random access memory (RRAM) based reconfigurable logic provides a temporal programmable dimension to realize Boolean logic functions and is regarded as a promising route to build non-von Neumann computing architecture. In this work, a reconfigurable operation method is proposed to perform nonvolatile sequential logic in a HfO 2 -based RRAM array. Eight kinds of Boolean logic functions can be implemented within the same hardware fabrics. During the logic computing processes, the RRAM devices in an array are flexibly configured in a bipolar or complementary structure. The validity was demonstrated by experimentally implemented NAND and XOR logic functions and a theoretically designed 1-bit full adder. With the trade-off between temporal and spatial computing complexity, our method makes better use of limited computing resources, thus provides an attractive scheme for the construction of logic-in-memory systems.

The effects of refreshing and elaboration on working memory performance, and their contributions to long-term memory formation.

PubMed

Bartsch, Lea M; Singmann, Henrik; Oberauer, Klaus

2018-03-19

Refreshing and elaboration are cognitive processes assumed to underlie verbal working-memory maintenance and assumed to support long-term memory formation. Whereas refreshing refers to the attentional focussing on representations, elaboration refers to linking representations in working memory into existing semantic networks. We measured the impact of instructed refreshing and elaboration on working and long-term memory separately, and investigated to what extent both processes are distinct in their contributions to working as well as long-term memory. Compared with a no-processing baseline, immediate memory was improved by repeating the items, but not by refreshing them. There was no credible effect of elaboration on working memory, except when items were repeated at the same time. Long-term memory benefited from elaboration, but not from refreshing the words. The results replicate the long-term memory benefit for elaboration, but do not support its beneficial role for working memory. Further, refreshing preserves immediate memory, but does not improve it beyond the level achieved without any processing.

Working memory and arithmetic calculation in children: the contributory roles of processing speed, short-term memory, and reading.

PubMed

Berg, Derek H

2008-04-01

The cognitive underpinnings of arithmetic calculation in children are noted to involve working memory; however, cognitive processes related to arithmetic calculation and working memory suggest that this relationship is more complex than stated previously. The purpose of this investigation was to examine the relative contributions of processing speed, short-term memory, working memory, and reading to arithmetic calculation in children. Results suggested four important findings. First, processing speed emerged as a significant contributor of arithmetic calculation only in relation to age-related differences in the general sample. Second, processing speed and short-term memory did not eliminate the contribution of working memory to arithmetic calculation. Third, individual working memory components--verbal working memory and visual-spatial working memory--each contributed unique variance to arithmetic calculation in the presence of all other variables. Fourth, a full model indicated that chronological age remained a significant contributor to arithmetic calculation in the presence of significant contributions from all other variables. Results are discussed in terms of directions for future research on working memory in arithmetic calculation.

Visual Working Memory Capacity and Proactive Interference

PubMed Central

Hartshorne, Joshua K.

2008-01-01

Background Visual working memory capacity is extremely limited and appears to be relatively immune to practice effects or the use of explicit strategies. The recent discovery that visual working memory tasks, like verbal working memory tasks, are subject to proactive interference, coupled with the fact that typical visual working memory tasks are particularly conducive to proactive interference, suggests that visual working memory capacity may be systematically under-estimated. Methodology/Principal Findings Working memory capacity was probed behaviorally in adult humans both in laboratory settings and via the Internet. Several experiments show that although the effect of proactive interference on visual working memory is significant and can last over several trials, it only changes the capacity estimate by about 15%. Conclusions/Significance This study further confirms the sharp limitations on visual working memory capacity, both in absolute terms and relative to verbal working memory. It is suggested that future research take these limitations into account in understanding differences across a variety of tasks between human adults, prelinguistic infants and nonlinguistic animals. PMID:18648493

Visual working memory capacity and proactive interference.

PubMed

Hartshorne, Joshua K

2008-07-23

Visual working memory capacity is extremely limited and appears to be relatively immune to practice effects or the use of explicit strategies. The recent discovery that visual working memory tasks, like verbal working memory tasks, are subject to proactive interference, coupled with the fact that typical visual working memory tasks are particularly conducive to proactive interference, suggests that visual working memory capacity may be systematically under-estimated. Working memory capacity was probed behaviorally in adult humans both in laboratory settings and via the Internet. Several experiments show that although the effect of proactive interference on visual working memory is significant and can last over several trials, it only changes the capacity estimate by about 15%. This study further confirms the sharp limitations on visual working memory capacity, both in absolute terms and relative to verbal working memory. It is suggested that future research take these limitations into account in understanding differences across a variety of tasks between human adults, prelinguistic infants and nonlinguistic animals.

Dissociation of working memory impairments and attention-deficit/hyperactivity disorder in the brain.

PubMed

Mattfeld, Aaron T; Whitfield-Gabrieli, Susan; Biederman, Joseph; Spencer, Thomas; Brown, Ariel; Fried, Ronna; Gabrieli, John D E

2016-01-01

Prevailing neuropsychological models of attention-deficit/hyperactivity disorder (ADHD) propose that ADHD arises from deficits in executive functions such as working memory, but accumulating clinical evidence suggests a dissociation between ADHD and executive dysfunctions. This study examined whether ADHD and working memory capacity are behaviorally and neurobiologically separable using functional magnetic resonance imaging (fMRI). Participants diagnosed with ADHD in childhood who subsequently remitted or persisted in their diagnosis as adults were characterized at follow-up in adulthood as either impaired or unimpaired in spatial working memory relative to controls who never had ADHD. ADHD participants with impaired spatial working memory performed worse than controls and ADHD participants with unimpaired working memory during an n-back working memory task while being scanned. Both controls and ADHD participants with unimpaired working memory exhibited significant linearly increasing activation in the inferior frontal junction, precuneus, lingual gyrus, and cerebellum as a function of working-memory load, and these activations did not differ significantly between these groups. ADHD participants with impaired working memory exhibited significant hypoactivation in the same regions, which was significantly different than both control participants and ADHD participants with unimpaired working memory. These findings support both a behavioral and neurobiological dissociation between ADHD and working memory capacity.

Dissociation of working memory impairments and attention-deficit/hyperactivity disorder in the brain

PubMed Central

Mattfeld, Aaron T.; Whitfield-Gabrieli, Susan; Biederman, Joseph; Spencer, Thomas; Brown, Ariel; Fried, Ronna; Gabrieli, John D.E.

2015-01-01

Prevailing neuropsychological models of attention-deficit/hyperactivity disorder (ADHD) propose that ADHD arises from deficits in executive functions such as working memory, but accumulating clinical evidence suggests a dissociation between ADHD and executive dysfunctions. This study examined whether ADHD and working memory capacity are behaviorally and neurobiologically separable using functional magnetic resonance imaging (fMRI). Participants diagnosed with ADHD in childhood who subsequently remitted or persisted in their diagnosis as adults were characterized at follow-up in adulthood as either impaired or unimpaired in spatial working memory relative to controls who never had ADHD. ADHD participants with impaired spatial working memory performed worse than controls and ADHD participants with unimpaired working memory during an n-back working memory task while being scanned. Both controls and ADHD participants with unimpaired working memory exhibited significant linearly increasing activation in the inferior frontal junction, precuneus, lingual gyrus, and cerebellum as a function of working-memory load, and these activations did not differ significantly between these groups. ADHD participants with impaired working memory exhibited significant hypoactivation in the same regions, which was significantly different than both control participants and ADHD participants with unimpaired working memory. These findings support both a behavioral and neurobiological dissociation between ADHD and working memory capacity. PMID:26900567

Working, declarative and procedural memory in specific language impairment

PubMed Central

Lum, Jarrad A.G.; Conti-Ramsden, Gina; Page, Debra; Ullman, Michael T.

2012-01-01

According to the Procedural Deficit Hypothesis (PDH), abnormalities of brain structures underlying procedural memory largely explain the language deficits in children with specific language impairment (SLI). These abnormalities are posited to result in core deficits of procedural memory, which in turn explain the grammar problems in the disorder. The abnormalities are also likely to lead to problems with other, non-procedural functions, such as working memory, that rely at least partly on the affected brain structures. In contrast, declarative memory is expected to remain largely intact, and should play an important compensatory role for grammar. These claims were tested by examining measures of working, declarative and procedural memory in 51 children with SLI and 51 matched typically-developing (TD) children (mean age 10). Working memory was assessed with the Working Memory Test Battery for Children, declarative memory with the Children’s Memory Scale, and procedural memory with a visuo-spatial Serial Reaction Time task. As compared to the TD children, the children with SLI were impaired at procedural memory, even when holding working memory constant. In contrast, they were spared at declarative memory for visual information, and at declarative memory in the verbal domain after controlling for working memory and language. Visuo-spatial short-term memory was intact, whereas verbal working memory was impaired, even when language deficits were held constant. Correlation analyses showed neither visuo-spatial nor verbal working memory was associated with either lexical or grammatical abilities in either the SLI or TD children. Declarative memory correlated with lexical abilities in both groups of children. Finally, grammatical abilities were associated with procedural memory in the TD children, but with declarative memory in the children with SLI. These findings replicate and extend previous studies of working, declarative and procedural memory in SLI. Overall, we suggest that the evidence largely supports the predictions of the PDH. PMID:21774923

Memory under pressure: secondary-task effects on contextual cueing of visual search.

PubMed

Annac, Efsun; Manginelli, Angela A; Pollmann, Stefan; Shi, Zhuanghua; Müller, Hermann J; Geyer, Thomas

2013-11-04

Repeated display configurations improve visual search. Recently, the question has arisen whether this contextual cueing effect (Chun & Jiang, 1998) is itself mediated by attention, both in terms of selectivity and processing resources deployed. While it is accepted that selective attention modulates contextual cueing (Jiang & Leung, 2005), there is an ongoing debate whether the cueing effect is affected by a secondary working memory (WM) task, specifically at which stage WM influences the cueing effect: the acquisition of configural associations (e.g., Travis, Mattingley, & Dux, 2013) versus the expression of learned associations (e.g., Manginelli, Langer, Klose, & Pollmann, 2013). The present study re-investigated this issue. Observers performed a visual search in combination with a spatial WM task. The latter was applied on either early or late search trials--so as to examine whether WM load hampers the acquisition of or retrieval from contextual memory. Additionally, the WM and search tasks were performed either temporally in parallel or in succession--so as to permit the effects of spatial WM load to be dissociated from those of executive load. The secondary WM task was found to affect cueing in late, but not early, experimental trials--though only when the search and WM tasks were performed in parallel. This pattern suggests that contextual cueing involves a spatial WM resource, with spatial WM providing a workspace linking the current search array with configural long-term memory; as a result, occupying this workspace by a secondary WM task hampers the expression of learned configural associations.

Spatial working memory load affects counting but not subitizing in enumeration.

PubMed

Shimomura, Tomonari; Kumada, Takatsune

2011-08-01

The present study investigated whether subitizing reflects capacity limitations associated with two types of working memory tasks. Under a dual-task situation, participants performed an enumeration task in conjunction with either a spatial (Experiment 1) or a nonspatial visual (Experiment 2) working memory task. Experiment 1 showed that spatial working memory load affected the slope of a counting function but did not affect subitizing performance or subitizing range. Experiment 2 showed that nonspatial visual working memory load affected neither enumeration efficiency nor subitizing range. Furthermore, in both spatial and nonspatial memory tasks, neither subitizing efficiency nor subitizing range was affected by amount of imposed memory load. In all the experiments, working memory load failed to influence slope, subitizing range, or overall reaction time. These findings suggest that subitizing is performed without either spatial or nonspatial working memory. A possible mechanism of subitizing with independent capacity of working memory is discussed.

Working memory involvement in stuttering: exploring the evidence and research implications.

PubMed

Bajaj, Amit

2007-01-01

Several studies of utterance planning and attention processes in stuttering have raised the prospect of working memory involvement in the disorder. In this paper, potential connections between stuttering and two elements of Baddeley's [Baddeley, A. D. (2003). Working memory: Looking back and looking forward. Neuroscience, 4, 829-839] working memory model, phonological memory and central executive, are posited. Empirical evidence is drawn from studies on phonological memory and dual-task performance among children and adults who stutter to examine support for the posited connections. Implications for research to examine working memory as one of the psycholinguistic bases of stuttering are presented. The reader will learn about and be able to: (1) appraise potential relationships between working memory and stuttering; (2) evaluate empirical evidence that suggests the possibility of working memory involvement in stuttering; and (3) identify research directions to explore the role of working memory in stuttering.

Changes in verbal and visuospatial working memory from Grade 1 to Grade 3 of primary school: Population longitudinal study.

PubMed

Nicolaou, E; Quach, J; Lum, J; Roberts, G; Spencer-Smith, M; Gathercole, S; Anderson, P J; Mensah, F K; Wake, M

2018-05-01

Adaptive working memory training is being implemented without an adequate understanding of developmental trajectories of working memory. We aimed to quantify from Grade 1 to Grade 3 of primary school (1) changes in verbal and visuospatial working memory and (2) whether low verbal and visuospatial working memory in Grade 1 predicts low working memory in Grade 3. The study design includes a population-based longitudinal study of 1,802 children (66% uptake from all 2,747 Grade 1 students) at 44 randomly selected primary schools in Melbourne, Australia. Backwards Digit Recall (verbal working memory) and Mister X (visuospatial working memory) screening measures from the Automated Working Memory Assessment (M = 100; SD = 15) were used to assess Grades 1 and 3 (ages 6-7 and 8-9 years) students. Low working memory was defined as ≥1 standard deviation below the standard score mean. Descriptive statistics addressed Aim 1, and predictive parameters addressed Aim 2. One thousand seventy (59%) of 1802 Grade 1 participants were reassessed in Grade 3. As expected for typically developing children, group mean standard scores were similar in Grades 1 and 3 for verbal, visuospatial, and overall working memory, but group mean raw scores increased markedly. Compared to "not low" children, those classified as having low working memory in Grade 1 showed much larger increases in both standard and raw scores across verbal, visuospatial, and overall working memory. Sensitivity was very low for Grade 1 low working memory predicting Grade 3 low classifications. Although mean changes in working memory standard scores between Grades 1 and 3 were minimal, we found that individual development varied widely, with marked natural resolution by Grade 3 in children who initially had low working memory. This may render brain-training interventions ineffective in the early school year ages, particularly if (as population-based programmes usually mandate) selection occurs within a screening paradigm. © 2017 John Wiley & Sons Ltd.

Contribution of auditory working memory to speech understanding in mandarin-speaking cochlear implant users.

PubMed

Tao, Duoduo; Deng, Rui; Jiang, Ye; Galvin, John J; Fu, Qian-Jie; Chen, Bing

2014-01-01

To investigate how auditory working memory relates to speech perception performance by Mandarin-speaking cochlear implant (CI) users. Auditory working memory and speech perception was measured in Mandarin-speaking CI and normal-hearing (NH) participants. Working memory capacity was measured using forward digit span and backward digit span; working memory efficiency was measured using articulation rate. Speech perception was assessed with: (a) word-in-sentence recognition in quiet, (b) word-in-sentence recognition in speech-shaped steady noise at +5 dB signal-to-noise ratio, (c) Chinese disyllable recognition in quiet, (d) Chinese lexical tone recognition in quiet. Self-reported school rank was also collected regarding performance in schoolwork. There was large inter-subject variability in auditory working memory and speech performance for CI participants. Working memory and speech performance were significantly poorer for CI than for NH participants. All three working memory measures were strongly correlated with each other for both CI and NH participants. Partial correlation analyses were performed on the CI data while controlling for demographic variables. Working memory efficiency was significantly correlated only with sentence recognition in quiet when working memory capacity was partialled out. Working memory capacity was correlated with disyllable recognition and school rank when efficiency was partialled out. There was no correlation between working memory and lexical tone recognition in the present CI participants. Mandarin-speaking CI users experience significant deficits in auditory working memory and speech performance compared with NH listeners. The present data suggest that auditory working memory may contribute to CI users' difficulties in speech understanding. The present pattern of results with Mandarin-speaking CI users is consistent with previous auditory working memory studies with English-speaking CI users, suggesting that the lexical importance of voice pitch cues (albeit poorly coded by the CI) did not influence the relationship between working memory and speech perception.

Does Working Memory Training Lead to Generalized Improvements in Children with Low Working Memory? A Randomized Controlled Trial

ERIC Educational Resources Information Center

Dunning, Darren L.; Holmes, Joni; Gathercole, Susan E.

2013-01-01

Children with low working memory typically make poor educational progress, and it has been speculated that difficulties in meeting the heavy working memory demands of the classroom may be a contributory factor. Intensive working memory training has been shown to boost performance on untrained memory tasks in a variety of populations. This first…

Working-memory training improves developmental dyslexia in Chinese children.

PubMed

Luo, Yan; Wang, Jing; Wu, Hanrong; Zhu, Dongmei; Zhang, Yu

2013-02-15

Although plasticity in the neural system underlies working memory, and working memory can be improved by training, there is thus far no evidence that children with developmental dyslexia can benefit from working-memory training. In the present study, thirty dyslexic children aged 8-11 years were recruited from an elementary school in Wuhan, China. They received working-memory training, including training in visuospatial memory, verbal memory, and central executive tasks. The difficulty of the tasks was adjusted based on the performance of each subject, and the training sessions lasted 40 minutes per day, for 5 weeks. The results showed that working-memory training significantly enhanced performance on the nontrained working memory tasks such as the visuospatial, the verbal domains, and central executive tasks in children with developmental dyslexia. More importantly, the visual rhyming task and reading fluency task were also significantly improved by training. Progress on working memory measures was related to changes in reading skills. These experimental findings indicate that working memory is a pivotal factor in reading development among children with developmental dyslexia, and interventions to improve working memory may help dyslexic children to become more proficient in reading.

Developmental changes in mental arithmetic: evidence for increased functional specialization in the left inferior parietal cortex.

PubMed

Rivera, S M; Reiss, A L; Eckert, M A; Menon, V

2005-11-01

Arithmetic reasoning is arguably one of the most important cognitive skills a child must master. Here we examine neurodevelopmental changes in mental arithmetic. Subjects (ages 8-19 years) viewed arithmetic equations and were asked to judge whether the results were correct or incorrect. During two-operand addition or subtraction trials, for which accuracy was comparable across age, older subjects showed greater activation in the left parietal cortex, along the supramarginal gyrus and adjoining anterior intra-parietal sulcus as well as the left lateral occipital temporal cortex. These age-related changes were not associated with alterations in gray matter density, and provide novel evidence for increased functional maturation with age. By contrast, younger subjects showed greater activation in the prefrontal cortex, including the dorsolateral and ventrolateral prefrontal cortex and the anterior cingulate cortex, suggesting that they require comparatively more working memory and attentional resources to achieve similar levels of mental arithmetic performance. Younger subjects also showed greater activation of the hippocampus and dorsal basal ganglia, reflecting the greater demands placed on both declarative and procedural memory systems. Our findings provide evidence for a process of increased functional specialization of the left inferior parietal cortex in mental arithmetic, a process that is accompanied by decreased dependence on memory and attentional resources with development.

Using perspective to resolve reference: The impact of cognitive load and motivation.

PubMed

Cane, James E; Ferguson, Heather J; Apperly, Ian A

2017-04-01

Research has demonstrated a link between perspective taking and working memory. Here we used eye tracking to examine the time course with which working memory load (WML) influences perspective-taking ability in a referential communication task and how motivation to take another's perspective modulates these effects. In Experiment 1, where there was no reward or time pressure, listeners only showed evidence of incorporating perspective knowledge during integration of the target object but did not anticipate reference to this common ground object during the pretarget-noun period. WML did not affect this perspective use. In Experiment 2, where a reward for speed and accuracy was applied, listeners used perspective cues to disambiguate the target object from the competitor object from the earliest moments of processing (i.e., during the pretarget-noun period), but only under low load. Under high load, responses were comparable with the control condition, where both objects were in common ground. Furthermore, attempts to initiate perspective-relevant responses under high load led to impaired recall on the concurrent WML task, indicating that perspective-relevant responses were drawing on limited cognitive resources. These results show that when there is ambiguity, perspective cues guide rapid referential interpretation when there is sufficient motivation and sufficient cognitive resources. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The contribution of working memory to divided attention.

PubMed

Santangelo, Valerio; Macaluso, Emiliano

2013-01-01

Previous studies have indicated that increasing working memory (WM) load can affect the attentional selection of signals originating from one object/location. Here we assessed whether WM load affects also the selection of multiple objects/locations (divided attention). Participants monitored either two object-categories (vs. one category; object-based divided attention) or two locations (vs. one location; space-based divided attention) while maintaining in WM either a variable number of objects (object-based WM load) or locations (space-based WM load). Behavioural results showed that WM load affected attentional performance irrespective of divided or focused attention. However, fMRI results showed that the activity associated with object-based divided attention increased linearly with increasing object-based WM load in the left and right intraparietal sulcus (IPS); while, in the same areas, activity associated with space-based divided attention was not affected by any type of WM load. These findings support the hypothesis that WM contributes to the maintenance of resource-demanding attentional sets in a domain-specific manner. Moreover, the dissociable impact of WM load on performance and brain activity suggests that increased IPS activation reflects a recruitment of additional, domain-specific processing resources that enable dual-task performance under conditions of high WM load and high attentional demand. Copyright © 2011 Wiley Periodicals, Inc.

Can Interactive Working Memory Training Improve Learning?

ERIC Educational Resources Information Center

Alloway, Tracy

2012-01-01

Background: Working memory is linked to learning outcomes and there is emerging evidence that training working memory can yield gains in working memory and fluid intelligence. Aims: The aim of the present study was to investigate whether interactive working memory training would transfer to acquired cognitive skills, such as vocabulary and…

Working memory training may increase working memory capacity but not fluid intelligence.

PubMed

Harrison, Tyler L; Shipstead, Zach; Hicks, Kenny L; Hambrick, David Z; Redick, Thomas S; Engle, Randall W

2013-12-01

Working memory is a critical element of complex cognition, particularly under conditions of distraction and interference. Measures of working memory capacity correlate positively with many measures of real-world cognition, including fluid intelligence. There have been numerous attempts to use training procedures to increase working memory capacity and thereby performance on the real-world tasks that rely on working memory capacity. In the study reported here, we demonstrated that training on complex working memory span tasks leads to improvement on similar tasks with different materials but that such training does not generalize to measures of fluid intelligence.

Spatial attention interacts with serial-order retrieval from verbal working memory.

PubMed

van Dijck, Jean-Philippe; Abrahamse, Elger L; Majerus, Steve; Fias, Wim

2013-09-01

The ability to maintain the serial order of events is recognized as a major function of working memory. Although general models of working memory postulate a close link between working memory and attention, such a link has so far not been proposed specifically for serial-order working memory. The present study provided the first empirical demonstration of a direct link between serial order in verbal working memory and spatial selective attention. We show that the retrieval of later items of a sequence stored in working memory-compared with that of earlier items-produces covert attentional shifts toward the right. This observation suggests the conceptually surprising notion that serial-order working memory, even for nonspatially defined verbal items, draws on spatial attention.

Working Memory Underpins Cognitive Development, Learning, and Education

PubMed Central

Cowan, Nelson

2014-01-01

Working memory is the retention of a small amount of information in a readily accessible form. It facilitates planning, comprehension, reasoning, and problem-solving. I examine the historical roots and conceptual development of the concept and the theoretical and practical implications of current debates about working memory mechanisms. Then I explore the nature of cognitive developmental improvements in working memory, the role of working memory in learning, and some potential implications of working memory and its development for the education of children and adults. The use of working memory is quite ubiquitous in human thought, but the best way to improve education using what we know about working memory is still controversial. I hope to provide some directions for research and educational practice. PMID:25346585

Working Memory Differences Between Children Living in Rural and Urban Poverty

PubMed Central

Tine, Michele

2014-01-01

This study was designed to investigate if the working memory profiles of children living in rural poverty are distinct from the working memory profiles of children living in urban poverty. Verbal and visuospatial working memory tasks were administered to sixth-grade students living in low-income rural, low-income urban, high-income rural, and high-income urban developmental contexts. Both low-income rural and low-income urban children showed working memory deficits compared with their high-income counterparts, but their deficits were distinct. Low-income urban children exhibited symmetrical verbal and visuospatial working memory deficits compared with their high-income urban counterparts. Meanwhile, low-income rural children exhibited asymmetrical deficits when compared with their high-income rural counterparts, with more extreme visuospatial working memory deficits than verbal working memory deficits. These results suggest that different types of poverty are associated with different working memory abilities. PMID:25554726

Working Memory Differences Between Children Living in Rural and Urban Poverty.

PubMed

Tine, Michele

2014-10-02

This study was designed to investigate if the working memory profiles of children living in rural poverty are distinct from the working memory profiles of children living in urban poverty. Verbal and visuospatial working memory tasks were administered to sixth-grade students living in low-income rural, low-income urban, high-income rural, and high-income urban developmental contexts. Both low-income rural and low-income urban children showed working memory deficits compared with their high-income counterparts, but their deficits were distinct. Low-income urban children exhibited symmetrical verbal and visuospatial working memory deficits compared with their high-income urban counterparts. Meanwhile, low-income rural children exhibited asymmetrical deficits when compared with their high-income rural counterparts, with more extreme visuospatial working memory deficits than verbal working memory deficits. These results suggest that different types of poverty are associated with different working memory abilities.

Do TRPC channels support working memory? Comparing modulations of TRPC channels and working memory through G-protein coupled receptors and neuromodulators.

PubMed

Reboreda, Antonio; Theissen, Frederik M; Valero-Aracama, Maria J; Arboit, Alberto; Corbu, Mihaela A; Yoshida, Motoharu

2018-03-01

Working memory is a crucial ability we use in daily life. However, the cellular mechanisms supporting working memory still remain largely unclear. A key component of working memory is persistent neural firing which is believed to serve short-term (hundreds of milliseconds up to tens of seconds) maintenance of necessary information. In this review, we will focus on the role of transient receptor potential canonical (TRPC) channels as a mechanism underlying persistent firing. Many years of in vitro work have been suggesting a crucial role of TRPC channels in working memory and temporal association tasks. If TRPC channels are indeed a central mechanism for working memory, manipulations which impair or facilitate working memory should have a similar effect on TRPC channel modulation. However, modulations of working memory and TRPC channels were never systematically compared, and it remains unanswered whether TRPC channels indeed contribute to working memory in vivo or not. In this article, we review the effects of G-protein coupled receptors (GPCR) and neuromodulators, including acetylcholine, noradrenalin, serotonin and dopamine, on working memory and TRPC channels. Based on comparisons, we argue that GPCR and downstream signaling pathways that activate TRPC, generally support working memory, while those that suppress TRPC channels impair it. However, depending on the channel types, areas, and systems tested, this is not the case in all studies. Further work to clarify involvement of specific TRPC channels in working memory tasks and how they are affected by neuromodulators is still necessary in the future. Copyright © 2018 Elsevier B.V. All rights reserved.

Development of bubble memory recorder onboard Japan Earth Resources Satellite-1

NASA Astrophysics Data System (ADS)

Araki, Tsunehiko; Ishida, Chu; Ochiai, Kiyoshi; Nozue, Tatsuhiro; Tachibana, Kyozo; Yoshida, Kazutoshi

The Bubble Memory Recorder (BMR) developed for use on the Earth Resources Satellite is described in terms of its design, capabilities, and functions. The specifications of the BMR are given listing memory capacity, functions, and interface types for data, command, and telemetry functions. The BMR has an emergency signal interface to provide contingency recording, and a satellite-separation signal interface can be turned on automatically by signal input. Data are stored in a novolatile memory device so that the memory is retained during power outages. The BMR is characterized by a capability for random access, nonvolatility, and a solid-state design that is useful for space operations since it does not disturb spacecraft attitude.

Effects of load and maintenance duration on the time course of information encoding and retrieval in working memory: from perceptual analysis to post-categorization processes.

PubMed

Pinal, Diego; Zurrón, Montserrat; Díaz, Fernando

2014-01-01

information encoding, maintenance, and retrieval; these are supported by brain activity in a network of frontal, parietal and temporal regions. Manipulation of WM load and duration of the maintenance period can modulate this activity. Although such modulations have been widely studied using the event-related potentials (ERP) technique, a precise description of the time course of brain activity during encoding and retrieval is still required. Here, we used this technique and principal component analysis to assess the time course of brain activity during encoding and retrieval in a delayed match to sample task. We also investigated the effects of memory load and duration of the maintenance period on ERP activity. Brain activity was similar during information encoding and retrieval and comprised six temporal factors, which closely matched the latency and scalp distribution of some ERP components: P1, N1, P2, N2, P300, and a slow wave. Changes in memory load modulated task performance and yielded variations in frontal lobe activation. Moreover, the P300 amplitude was smaller in the high than in the low load condition during encoding and retrieval. Conversely, the slow wave amplitude was higher in the high than in the low load condition during encoding, and the same was true for the N2 amplitude during retrieval. Thus, during encoding, memory load appears to modulate the processing resources for context updating and post-categorization processes, and during retrieval it modulates resources for stimulus classification and context updating. Besides, despite the lack of differences in task performance related to duration of the maintenance period, larger N2 amplitude and stronger activation of the left temporal lobe after long than after short maintenance periods were found during information retrieval. Thus, results regarding the duration of maintenance period were complex, and future work is required to test the time-based decay theory predictions.

Conceptualizing and Measuring Working Memory and its Relationship to Aphasia

PubMed Central

Wright, Heather Harris; Fergadiotis, Gerasimos

2011-01-01

Background General agreement exists in the literature that individuals with aphasia can exhibit a working memory deficit that contributes to their language processing impairments. Though conceptualized within different working memory frameworks, researchers have suggested that individuals with aphasia have limited working memory capacity, impaired attention-control processes as well as impaired inhibitory mechanisms. However, across studies investigating working memory ability in individuals with aphasia, different measures have been used to quantify their working memory ability and identify the relationship between working memory and language performance. Aims The primary objectives of this article are to (1) review current working memory theoretical frameworks, (2) review tasks used to measure working memory, and (3) discuss findings from studies that have investigated working memory as they relate to language processing in aphasia. Main Contribution Though findings have been consistent across studies investigating working memory ability in individuals with aphasia, discussion of how working memory is conceptualized and defined is often missing, as is discussion of results within a theoretical framework. This is critical, as working memory is conceptualized differently across the different theoretical frameworks. They differ in explaining what limits capacity and the source of individual differences as well as how information is encoded, maintained, and retrieved. When test methods are considered within a theoretical framework, specific hypotheses can be tested and stronger conclusions that are less susceptible to different interpretations can be made. Conclusions Working memory ability has been investigated in numerous studies with individuals with aphasia. To better understand the underlying cognitive constructs that contribute to the language deficits exhibited by individuals with aphasia, future investigations should operationally define the cognitive constructs of interest and discuss findings within theoretical frameworks. PMID:22639480

Resource Isolation Method for Program’S Performance on CMP

NASA Astrophysics Data System (ADS)

Guan, Ti; Liu, Chunxiu; Xu, Zheng; Li, Huicong; Ma, Qiang

2017-10-01

Data center and cloud computing are more popular, which make more benefits for customers and the providers. However, in data center or clusters, commonly there is more than one program running on one server, but programs may interference with each other. The interference may take a little effect, however, the interference may cause serious drop down of performance. In order to avoid the performance interference problem, the mechanism of isolate resource for different programs is a better choice. In this paper we propose a light cost resource isolation method to improve program’s performance. This method uses Cgroups to set the dedicated CPU and memory resource for a program, aiming at to guarantee the program’s performance. There are three engines to realize this method: Program Monitor Engine top program’s resource usage of CPU and memory and transfer the information to Resource Assignment Engine; Resource Assignment Engine calculates the size of CPU and memory resource should be applied for the program; Cgroups Control Engine divide resource by Linux tool Cgroups, and drag program in control group for execution. The experiment result show that making use of the resource isolation method proposed by our paper, program’s performance can be improved.

Changes in Brain Network Efficiency and Working Memory Performance in Aging

PubMed Central

Stanley, Matthew L.; Simpson, Sean L.; Dagenbach, Dale; Lyday, Robert G.; Burdette, Jonathan H.; Laurienti, Paul J.

2015-01-01

Working memory is a complex psychological construct referring to the temporary storage and active processing of information. We used functional connectivity brain network metrics quantifying local and global efficiency of information transfer for predicting individual variability in working memory performance on an n-back task in both young (n = 14) and older (n = 15) adults. Individual differences in both local and global efficiency during the working memory task were significant predictors of working memory performance in addition to age (and an interaction between age and global efficiency). Decreases in local efficiency during the working memory task were associated with better working memory performance in both age cohorts. In contrast, increases in global efficiency were associated with much better working performance for young participants; however, increases in global efficiency were associated with a slight decrease in working memory performance for older participants. Individual differences in local and global efficiency during resting-state sessions were not significant predictors of working memory performance. Significant group whole-brain functional network decreases in local efficiency also were observed during the working memory task compared to rest, whereas no significant differences were observed in network global efficiency. These results are discussed in relation to recently developed models of age-related differences in working memory. PMID:25875001

Changes in brain network efficiency and working memory performance in aging.

PubMed

Stanley, Matthew L; Simpson, Sean L; Dagenbach, Dale; Lyday, Robert G; Burdette, Jonathan H; Laurienti, Paul J

2015-01-01

Working memory is a complex psychological construct referring to the temporary storage and active processing of information. We used functional connectivity brain network metrics quantifying local and global efficiency of information transfer for predicting individual variability in working memory performance on an n-back task in both young (n = 14) and older (n = 15) adults. Individual differences in both local and global efficiency during the working memory task were significant predictors of working memory performance in addition to age (and an interaction between age and global efficiency). Decreases in local efficiency during the working memory task were associated with better working memory performance in both age cohorts. In contrast, increases in global efficiency were associated with much better working performance for young participants; however, increases in global efficiency were associated with a slight decrease in working memory performance for older participants. Individual differences in local and global efficiency during resting-state sessions were not significant predictors of working memory performance. Significant group whole-brain functional network decreases in local efficiency also were observed during the working memory task compared to rest, whereas no significant differences were observed in network global efficiency. These results are discussed in relation to recently developed models of age-related differences in working memory.

Effects of working memory contents and perceptual load on distractor processing: When a response-related distractor is held in working memory.

PubMed

Koshino, Hideya

2017-01-01

Working memory and attention are closely related. Recent research has shown that working memory can be viewed as internally directed attention. Working memory can affect attention in at least two ways. One is the effect of working memory load on attention, and the other is the effect of working memory contents on attention. In the present study, an interaction between working memory contents and perceptual load in distractor processing was investigated. Participants performed a perceptual load task in a standard form in one condition (Single task). In the other condition, a response-related distractor was maintained in working memory, rather than presented in the same stimulus display as a target (Dual task). For the Dual task condition, a significant compatibility effect was found under high perceptual load; however, there was no compatibility effect under low perceptual load. These results suggest that the way the contents of working memory affect visual search depends on perceptual load. Copyright © 2016 Elsevier B.V. All rights reserved.

Motor learning and working memory in children born preterm: a systematic review.

PubMed

Jongbloed-Pereboom, Marjolein; Janssen, Anjo J W M; Steenbergen, Bert; Nijhuis-van der Sanden, Maria W G

2012-04-01

Children born preterm have a higher risk for developing motor, cognitive, and behavioral problems. Motor problems can occur in combination with working memory problems, and working memory is important for explicit learning of motor skills. The relation between motor learning and working memory has never been reviewed. The goal of this review was to provide an overview of motor learning, visual working memory and the role of working memory on motor learning in preterm children. A systematic review conducted in four databases identified 38 relevant articles, which were evaluated for methodological quality. Only 4 of 38 articles discussed motor learning in preterm children. Thirty-four studies reported on visual working memory; preterm birth affected performance on visual working memory tests. Information regarding motor learning and the role of working memory on the different components of motor learning was not available. Future research should address this issue. Insight in the relation between motor learning and visual working memory may contribute to the development of evidence based intervention programs for children born preterm. Copyright © 2012 Elsevier Ltd. All rights reserved.

Manipulations of attention dissociate fragile visual short-term memory from visual working memory.

PubMed

Vandenbroucke, Annelinde R E; Sligte, Ilja G; Lamme, Victor A F

2011-05-01

People often rely on information that is no longer in view, but maintained in visual short-term memory (VSTM). Traditionally, VSTM is thought to operate on either a short time-scale with high capacity - iconic memory - or a long time scale with small capacity - visual working memory. Recent research suggests that in addition, an intermediate stage of memory in between iconic memory and visual working memory exists. This intermediate stage has a large capacity and a lifetime of several seconds, but is easily overwritten by new stimulation. We therefore termed it fragile VSTM. In previous studies, fragile VSTM has been dissociated from iconic memory by the characteristics of the memory trace. In the present study, we dissociated fragile VSTM from visual working memory by showing a differentiation in their dependency on attention. A decrease in attention during presentation of the stimulus array greatly reduced the capacity of visual working memory, while this had only a small effect on the capacity of fragile VSTM. We conclude that fragile VSTM is a separate memory store from visual working memory. Thus, a tripartite division of VSTM appears to be in place, comprising iconic memory, fragile VSTM and visual working memory. Copyright © 2011 Elsevier Ltd. All rights reserved.

MODA A Framework for Memory Centric Performance Characterization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shrestha, Sunil; Su, Chun-Yi; White, Amanda M.

2012-06-29

In the age of massive parallelism, the focus of performance analysis has switched from the processor and related structures to the memory and I/O resources. Adapting to this new reality, a performance analysis tool has to provide a way to analyze resource usage to pinpoint existing and potential problems in a given application. This paper provides an overview of the Memory Observant Data Analysis (MODA) tool, a memory-centric tool first implemented on the Cray XMT supercomputer. Throughout the paper, MODA's capabilities have been showcased with experiments done on matrix multiply and Graph-500 application codes.

Working memory consolidation: insights from studies on attention and working memory.

PubMed

Ricker, Timothy J; Nieuwenstein, Mark R; Bayliss, Donna M; Barrouillet, Pierre

2018-04-10

Working memory, the system that maintains a limited set of representations for immediate use in cognition, is a central part of human cognition. Three processes have recently been proposed to govern information storage in working memory: consolidation, refreshing, and removal. Here, we discuss in detail the theoretical construct of working memory consolidation, a process critical to the creation of a stable working memory representation. We present a brief overview of the research that indicated the need for a construct such as working memory consolidation and the subsequent research that has helped to define the parameters of the construct. We then move on to explicitly state the points of agreement as to what processes are involved in working memory consolidation. © 2018 New York Academy of Sciences.

A functional magnetic resonance imaging study of working memory abnormalities in schizophrenia.

PubMed

Johnson, Matthew R; Morris, Nicholas A; Astur, Robert S; Calhoun, Vince D; Mathalon, Daniel H; Kiehl, Kent A; Pearlson, Godfrey D

2006-07-01

Previous neuroimaging studies of working memory (WM) in schizophrenia, typically focusing on dorsolateral prefrontal cortex, yield conflicting results, possibly because of varied choice of tasks and analysis techniques. We examined neural function changes at several WM loads to derive a more complete picture of WM dysfunction in schizophrenia. We used a version of the Sternberg Item Recognition Paradigm to test WM function at five distinct loads. Eighteen schizophrenia patients and 18 matched healthy controls were scanned with functional magnetic resonance imaging at 3 Tesla. Patterns of both overactivation and underactivation in patients were observed depending on WM load. Patients' activation was generally less responsive to load changes than control subjects', and different patterns of between-group differences were observed for memory encoding and retrieval. In the specific case of successful retrieval, patients recruited additional neural circuits unused by control subjects. Behavioral effects were generally consistent with these imaging results. Differential findings of overactivation and underactivation may be attributable to patients' decreased ability to focus and allocate neural resources at task-appropriate levels. Additionally, differences between encoding and retrieval suggest that WM dysfunction may be manifested differently during the distinct phases of encoding, maintenance, and retrieval.

Hänsel, Gretel and the slime mould—how an external spatial memory aids navigation in complex environments

NASA Astrophysics Data System (ADS)

Smith-Ferguson, Jules; Reid, Chris R.; Latty, Tanya; Beekman, Madeleine

2017-10-01

The ability to navigate through an environment is critical to most organisms’ ability to survive and reproduce. The presence of a memory system greatly enhances navigational success. Therefore, natural selection is likely to drive the creation of memory systems, even in non-neuronal organisms, if having such a system is adaptive. Here we examine if the external spatial memory system present in the acellular slime mould, Physarum polycephalum, provides an adaptive advantage for resource acquisition. P. polycephalum lays tracks of extracellular slime as it moves through its environment. Previous work has shown that the presence of extracellular slime allows the organism to escape from a trap in laboratory experiments simply by avoiding areas previously explored. Here we further investigate the benefits of using extracellular slime as an external spatial memory by testing the organism’s ability to navigate through environments of differing complexity with and without the ability to use its external memory. Our results suggest that the external memory has an adaptive advantage in ‘open’ and simple bounded environments. However, in a complex bounded environment, the extracellular slime provides no advantage, and may even negatively affect the organism’s navigational abilities. Our results indicate that the exact experimental set up matters if one wants to fully understand how the presence of extracellular slime affects the slime mould’s search behaviour.

Effective visual working memory capacity: an emergent effect from the neural dynamics in an attractor network.

PubMed

Dempere-Marco, Laura; Melcher, David P; Deco, Gustavo

2012-01-01

The study of working memory capacity is of outmost importance in cognitive psychology as working memory is at the basis of general cognitive function. Although the working memory capacity limit has been thoroughly studied, its origin still remains a matter of strong debate. Only recently has the role of visual saliency in modulating working memory storage capacity been assessed experimentally and proved to provide valuable insights into working memory function. In the computational arena, attractor networks have successfully accounted for psychophysical and neurophysiological data in numerous working memory tasks given their ability to produce a sustained elevated firing rate during a delay period. Here we investigate the mechanisms underlying working memory capacity by means of a biophysically-realistic attractor network with spiking neurons while accounting for two recent experimental observations: 1) the presence of a visually salient item reduces the number of items that can be held in working memory, and 2) visually salient items are commonly kept in memory at the cost of not keeping as many non-salient items. Our model suggests that working memory capacity is determined by two fundamental processes: encoding of visual items into working memory and maintenance of the encoded items upon their removal from the visual display. While maintenance critically depends on the constraints that lateral inhibition imposes to the mnemonic activity, encoding is limited by the ability of the stimulated neural assemblies to reach a sufficiently high level of excitation, a process governed by the dynamics of competition and cooperation among neuronal pools. Encoding is therefore contingent upon the visual working memory task and has led us to introduce the concept of effective working memory capacity (eWMC) in contrast to the maximal upper capacity limit only reached under ideal conditions.

Effective Visual Working Memory Capacity: An Emergent Effect from the Neural Dynamics in an Attractor Network

PubMed Central

Dempere-Marco, Laura; Melcher, David P.; Deco, Gustavo

2012-01-01

The study of working memory capacity is of outmost importance in cognitive psychology as working memory is at the basis of general cognitive function. Although the working memory capacity limit has been thoroughly studied, its origin still remains a matter of strong debate. Only recently has the role of visual saliency in modulating working memory storage capacity been assessed experimentally and proved to provide valuable insights into working memory function. In the computational arena, attractor networks have successfully accounted for psychophysical and neurophysiological data in numerous working memory tasks given their ability to produce a sustained elevated firing rate during a delay period. Here we investigate the mechanisms underlying working memory capacity by means of a biophysically-realistic attractor network with spiking neurons while accounting for two recent experimental observations: 1) the presence of a visually salient item reduces the number of items that can be held in working memory, and 2) visually salient items are commonly kept in memory at the cost of not keeping as many non-salient items. Our model suggests that working memory capacity is determined by two fundamental processes: encoding of visual items into working memory and maintenance of the encoded items upon their removal from the visual display. While maintenance critically depends on the constraints that lateral inhibition imposes to the mnemonic activity, encoding is limited by the ability of the stimulated neural assemblies to reach a sufficiently high level of excitation, a process governed by the dynamics of competition and cooperation among neuronal pools. Encoding is therefore contingent upon the visual working memory task and has led us to introduce the concept of effective working memory capacity (eWMC) in contrast to the maximal upper capacity limit only reached under ideal conditions. PMID:22952608

Working memory span in mild cognitive impairment. Influence of processing speed and cognitive reserve.

PubMed

Facal, David; Juncos-Rabadán, Onésimo; Pereiro, Arturo X; Lojo-Seoane, Cristina

2014-04-01

Mild cognitive impairment (MCI) often includes episodic memory impairment, but can also involve other types of cognitive decline. Although previous studies have shown poorer performance of MCI patients in working memory (WM) span tasks, different MCI subgroups were not studied. In the present exploratory study, 145 participants underwent extensive cognitive evaluation, which included three different WM span tasks, and were classified into the following groups: multiple-domain amnestic MCI (mda-MCI), single-domain amnestic MCI (sda-MCI), and controls. General linear model was conducted by considering the WM span tasks as the within-subject factor; the group (mda-MCI, sda-MCI, and controls) as the inter-subject factor; and processing speed, vocabulary and age as covariates. Multiple linear regression models were also used to test the influence of processing speed, vocabulary, and other cognitive reserve (CR) proxies. Results indicate different levels of impairment of WM, with more severe impairment in mda-MCI patients. The differences were still present when processing resources and CR were controlled. Between-group differences can be understood as a manifestation of the greater severity and widespread memory impairment in mda-MCI patients and may contribute to a better understanding of continuum from normal controls to mda-MCI patients. Processing speed and CR have a limited influence on WM scores, reducing but not removing differences between groups.

Pigeons (Columba livia) know when they will need hints: prospective metacognition for reference memory?

PubMed

Iwasaki, Sumie; Watanabe, Sota; Fujita, Kazuo

2018-03-01

Despite their impressive cognitive abilities, avian species have shown less evidence for metacognition than mammals. We suspect that commonly used tasks such as matching to sample might be too demanding to allow metacognitive processing within birds' working memory. Here, we examined whether pigeons could control their behavior as a function of knowledge levels on a three-item sequence learning task, a reference memory task supposedly requiring fewer working memory resources. The experiment used two types of lists differing in familiarity. One was familiar to the pigeons through repeated exposure, whereas the other was novel in every new session. In test sessions, pigeons could choose between a trial with a hint specifying the next item to peck and one with no hint. However, successful responses in trials with a hint resulted in lowered rates of primary reinforcement: .60 in the first test and .75 in the second. Results showed that two of four pigeons chose the trial with a hint significantly more often before receiving a novel list than the familiar list in the four sessions of the first test, and three did so in the second test. Impressively, one bird showed robust evidence in the very first sessions in both tests. These results suggest that pigeons may monitor their long-term knowledge states and thereby control their environment before starting to solve a task.

Working memory, short-term memory and reading proficiency in school-age children with cochlear implants.

PubMed

Bharadwaj, Sneha V; Maricle, Denise; Green, Laura; Allman, Tamby

2015-10-01

The objective of the study was to examine short-term memory and working memory through both visual and auditory tasks in school-age children with cochlear implants. The relationship between the performance on these cognitive skills and reading as well as language outcomes were examined in these children. Ten children between the ages of 7 and 11 years with early-onset bilateral severe-profound hearing loss participated in the study. Auditory and visual short-term memory, auditory and visual working memory subtests and verbal knowledge measures were assessed using the Woodcock Johnson III Tests of Cognitive Abilities, the Wechsler Intelligence Scale for Children-IV Integrated and the Kaufman Assessment Battery for Children II. Reading outcomes were assessed using the Woodcock Reading Mastery Test III. Performance on visual short-term memory and visual working memory measures in children with cochlear implants was within the average range when compared to the normative mean. However, auditory short-term memory and auditory working memory measures were below average when compared to the normative mean. Performance was also below average on all verbal knowledge measures. Regarding reading outcomes, children with cochlear implants scored below average for listening and passage comprehension tasks and these measures were positively correlated to visual short-term memory, visual working memory and auditory short-term memory. Performance on auditory working memory subtests was not related to reading or language outcomes. The children with cochlear implants in this study demonstrated better performance in visual (spatial) working memory and short-term memory skills than in auditory working memory and auditory short-term memory skills. Significant positive relationships were found between visual working memory and reading outcomes. The results of the study provide support for the idea that WM capacity is modality specific in children with hearing loss. Based on these findings, reading instruction that capitalizes on the strengths in visual short-term memory and working memory is suggested for young children with early-onset hearing loss. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Examining procedural working memory processing in obsessive-compulsive disorder.

PubMed

Shahar, Nitzan; Teodorescu, Andrei R; Anholt, Gideon E; Karmon-Presser, Anat; Meiran, Nachshon

2017-07-01

Previous research has suggested that a deficit in working memory might underlie the difficulty of obsessive-compulsive disorder (OCD) patients to control their thoughts and actions. However, a recent meta-analyses found only small effect sizes for working memory deficits in OCD. Recently, a distinction has been made between declarative and procedural working memory. Working memory in OCD was tested mostly using declarative measurements. However, OCD symptoms typically concerns actions, making procedural working-memory more relevant. Here, we tested the operation of procedural working memory in OCD. Participants with OCD and healthy controls performed a battery of choice reaction tasks under high and low procedural working memory demands. Reaction-times (RT) were estimated using ex-Gaussian distribution fitting, revealing no group differences in the size of the RT distribution tail (i.e., τ parameter), known to be sensitive to procedural working memory manipulations. Group differences, unrelated to working memory manipulations, were found in the leading-edge of the RT distribution and analyzed using a two-stage evidence accumulation model. Modeling results suggested that perceptual difficulties might underlie the current group differences. In conclusion, our results suggest that procedural working-memory processing is most likely intact in OCD, and raise a novel, yet untested assumption regarding perceptual deficits in OCD. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Components of working memory and visual selective attention.

PubMed

Burnham, Bryan R; Sabia, Matthew; Langan, Catherine

2014-02-01

Load theory (Lavie, N., Hirst, A., De Fockert, J. W., & Viding, E. [2004]. Load theory of selective attention and cognitive control. Journal of Experimental Psychology: General, 133, 339-354.) proposes that control of attention depends on the amount and type of load that is imposed by current processing. Specifically, perceptual load should lead to efficient distractor rejection, whereas working memory load (dual-task coordination) should hinder distractor rejection. Studies support load theory's prediction that working memory load will lead to larger distractor effects; however, these studies used secondary tasks that required only verbal working memory and the central executive. The present study examined which other working memory components (visual, spatial, and phonological) influence visual selective attention. Subjects completed an attentional capture task alone (single-task) or while engaged in a working memory task (dual-task). Results showed that along with the central executive, visual and spatial working memory influenced selective attention, but phonological working memory did not. Specifically, attentional capture was larger when visual or spatial working memory was loaded, but phonological working memory load did not affect attentional capture. The results are consistent with load theory and suggest specific components of working memory influence visual selective attention. PsycINFO Database Record (c) 2014 APA, all rights reserved.

The effects of eye movements on emotional memories: using an objective measure of cognitive load.

PubMed

van Veen, Suzanne C; Engelhard, Iris M; van den Hout, Marcel A

2016-01-01

Eye movement desensitization and reprocessing (EMDR) is an effective treatment for posttraumatic stress disorder. The working memory (WM) theory explains its efficacy: recall of an aversive memory and making eye movements (EM) both produce cognitive load, and competition for the limited WM resources reduces the memory's vividness and emotionality. The present study tested several predictions from WM theory. We hypothesized that 1) recall of an aversive autobiographical memory loads WM compared to no recall, and 2) recall with EM reduces the vividness, emotionality, and cognitive load of recalling the memory more than only recall or only cognitive effort (i.e., recall of an irrelevant memory with EM). Undergraduates (N=108) were randomly assigned to one of three conditions: 1) recall relevant memory with EM, 2) recall relevant memory without EM, and 3) recall irrelevant memory with EM. We used a random interval repetition task to measure the cognitive load of recalling the memory. Participants responded to randomly administered beeps, with or without recalling the memory. The degree to which participants slow down during recall provides an index of cognitive load. We measured the cognitive load and self-reported vividness and emotionality before, halfway through (8×24 s), and after (16×24 s) the intervention. Reaction times slowed down during memory recall compared to no recall. The recall relevant with EM condition showed a larger decrease in self-reported vividness and emotionality than the control conditions. The cognitive load of recalling the memory also decreased in this condition but not consistently more than in the control conditions. Recall of an aversive memory loads WM, but drops in vividness and emotionality do not immediately reduce the cognitive load of recalling the memory. More research is needed to find objective measures that could capture changes in the quality of the memory.

Executive Resources and Item-Context Binding: Exploring the Influence of Concurrent Inhibition, Updating, and Shifting Tasks on Context Memory

PubMed Central

Nieznański, Marek; Obidziński, Michał; Zyskowska, Emilia; Niedziałkowska, Daria

2015-01-01

Previous research has demonstrated that context memory performance decreases as a result of cognitive load. However, the role of specific executive resources availability has not been specified yet. In a dual-task experiment, participants performed three kinds of concurrent task engaging: inhibition, updating, or shifting operations. In comparison with a no-load single-task condition, a significant decrease in item and context memory was observed, regardless of the kind of executive task. When executive load conditions were compared with non-specific cognitive load conditions, a significant interference effect was observed in the case of the inhibition task. The inhibition process appears to be an aspect of executive control, which relies on the same resource as item-context binding does, especially when binding refers to associations retrieved from long-term memory. PMID:26435761

A shared resource between declarative memory and motor memory.

PubMed

Keisler, Aysha; Shadmehr, Reza

2010-11-03

The neural systems that support motor adaptation in humans are thought to be distinct from those that support the declarative system. Yet, during motor adaptation changes in motor commands are supported by a fast adaptive process that has important properties (rapid learning, fast decay) that are usually associated with the declarative system. The fast process can be contrasted to a slow adaptive process that also supports motor memory, but learns gradually and shows resistance to forgetting. Here we show that after people stop performing a motor task, the fast motor memory can be disrupted by a task that engages declarative memory, but the slow motor memory is immune from this interference. Furthermore, we find that the fast/declarative component plays a major role in the consolidation of the slow motor memory. Because of the competitive nature of declarative and nondeclarative memory during consolidation, impairment of the fast/declarative component leads to improvements in the slow/nondeclarative component. Therefore, the fast process that supports formation of motor memory is not only neurally distinct from the slow process, but it shares critical resources with the declarative memory system.

A shared resource between declarative memory and motor memory

PubMed Central

Keisler, Aysha; Shadmehr, Reza

2010-01-01

The neural systems that support motor adaptation in humans are thought to be distinct from those that support the declarative system. Yet, during motor adaptation changes in motor commands are supported by a fast adaptive process that has important properties (rapid learning, fast decay) that are usually associated with the declarative system. The fast process can be contrasted to a slow adaptive process that also supports motor memory, but learns gradually and shows resistance to forgetting. Here we show that after people stop performing a motor task, the fast motor memory can be disrupted by a task that engages declarative memory, but the slow motor memory is immune from this interference. Furthermore, we find that the fast/declarative component plays a major role in the consolidation of the slow motor memory. Because of the competitive nature of declarative and non-declarative memory during consolidation, impairment of the fast/declarative component leads to improvements in the slow/non-declarative component. Therefore, the fast process that supports formation of motor memory is not only neurally distinct from the slow process, but it shares critical resources with the declarative memory system. PMID:21048140

Effectiveness of Working Memory Training among Subjects Currently on Sick Leave Due to Complex Symptoms.

PubMed

Aasvik, Julie K; Woodhouse, Astrid; Stiles, Tore C; Jacobsen, Henrik B; Landmark, Tormod; Glette, Mari; Borchgrevink, Petter C; Landrø, Nils I

2016-01-01

Introduction: The current study examined if adaptive working memory training (Cogmed QM) has the potential to improve inhibitory control, working memory capacity, and perceptions of memory functioning in a group of patients currently on sick leave due to symptoms of pain, insomnia, fatigue, depression and anxiety. Participants who were referred to a vocational rehabilitation center volunteered to take part in the study. Methods: Participants were randomly assigned to either a training condition ( N = 25) or a control condition ( N = 29). Participants in the training condition received working memory training in addition to the clinical intervention offered as part of the rehabilitation program, while participants in the control condition received treatment as usual i.e., the rehabilitation program only. Inhibitory control was measured by The Stop Signal Task, working memory was assessed by the Spatial Working Memory Test, while perceptions of memory functioning were assessed by The Everyday Memory Questionnaire-Revised. Results: Participants in the training group showed a significant improvement on the post-tests of inhibitory control when compared with the comparison group ( p = 0.025). The groups did not differ on the post-tests of working memory. Both groups reported less memory problems at post-testing, but there was no sizeable difference between the two groups. Conclusions: Results indicate that working memory training does not improve general working memory capacity per se . Nor does it seem to give any added effects in terms of targeting and improving self-perceived memory functioning. Results do, however, provide evidence to suggest that inhibitory control is accessible and susceptible to modification by adaptive working memory training.

Reactive Goal Decomposition Hierarchies for On-Board Autonomy

NASA Astrophysics Data System (ADS)

Hartmann, L.

2002-01-01

As our experience grows, space missions and systems are expected to address ever more complex and demanding requirements with fewer resources (e.g., mass, power, budget). One approach to accommodating these higher expectations is to increase the level of autonomy to improve the capabilities and robustness of on- board systems and to simplify operations. The goal decomposition hierarchies described here provide a simple but powerful form of goal-directed behavior that is relatively easy to implement for space systems. A goal corresponds to a state or condition that an operator of the space system would like to bring about. In the system described here goals are decomposed into simpler subgoals until the subgoals are simple enough to execute directly. For each goal there is an activation condition and a set of decompositions. The decompositions correspond to different ways of achieving the higher level goal. Each decomposition contains a gating condition and a set of subgoals to be "executed" sequentially or in parallel. The gating conditions are evaluated in order and for the first one that is true, the corresponding decomposition is executed in order to achieve the higher level goal. The activation condition specifies global conditions (i.e., for all decompositions of the goal) that need to hold in order for the goal to be achieved. In real-time, parameters and state information are passed between goals and subgoals in the decomposition; a termination indication (success, failure, degree) is passed up when a decomposition finishes executing. The lowest level decompositions include servo control loops and finite state machines for generating control signals and sequencing i/o. Semaphores and shared memory are used to synchronize and coordinate decompositions that execute in parallel. The goal decomposition hierarchy is reactive in that the generated behavior is sensitive to the real-time state of the system and the environment. That is, the system is able to react to state and environment and in general can terminate the execution of a decomposition and attempt a new decomposition at any level in the hierarchy. This goal decomposition system is suitable for workstation, microprocessor and fpga implementation and thus is able to support the full range of prototyping activities, from mission design in the laboratory to development of the fpga firmware for the flight system. This approach is based on previous artificial intelligence work including (1) Brooks' subsumption architecture for robot control, (2) Firby's Reactive Action Package System (RAPS) for mediating between high level automated planning and low level execution and (3) hierarchical task networks for automated planning. Reactive goal decomposition hierarchies can be used for a wide variety of on-board autonomy applications including automating low level operation sequences (such as scheduling prerequisite operations, e.g., heaters, warm-up periods, monitoring power constraints), coordinating multiple spacecraft as in formation flying and constellations, robot manipulator operations, rendez-vous, docking, servicing, assembly, on-orbit maintenance, planetary rover operations, solar system and interstellar probes, intelligent science data gathering and disaster early warning. Goal decomposition hierarchies can support high level fault tolerance. Given models of on-board resources and goals to accomplish, the decomposition hierarchy could allocate resources to goals taking into account existing faults and in real-time reallocating resources as new faults arise. Resources to be modeled include memory (e.g., ROM, FPGA configuration memory, processor memory, payload instrument memory), processors, on-board and interspacecraft network nodes and links, sensors, actuators (e.g., attitude determination and control, guidance and navigation) and payload instruments. A goal decomposition hierarchy could be defined to map mission goals and tasks to available on-board resources. As faults occur and are detected the resource allocation is modified to avoid using the faulty resource. Goal decomposition hierarchies can implement variable autonomy (in which the operator chooses to command the system at a high or low level, mixed initiative planning (in which the system is able to interact with the operator, e.g, to request operator intervention when a working envelope is exceeded) and distributed control (in which, for example, multiple spacecraft cooperate to accomplish a task without a fixed master). The full paper will describe in greater detail how goal decompositions work, how they can be implemented, techniques for implementing a candidate application and the current state of the fpga implementation.

Working Memory and Reasoning: The Processing Loads Imposed by Analogies.

ERIC Educational Resources Information Center

Halford, Graeme S.

The proposals concerning working memory outlined in this paper involve the architecture of working memory, the reasoning mechanisms that draw on it, and the ways in which working memory may develop with age. Ways of assessing task demands and children's working memory capacities are also considered. It is noted that there is long-standing evidence…

Executive Functions and Working Memory Behaviours in Children with a Poor Working Memory

ERIC Educational Resources Information Center

St. Clair-Thompson, Helen L.

2011-01-01

Previous research has suggested that working memory difficulties play an integral role in children's underachievement at school. However, working memory is just one of several executive functions. The extent to which problems in working memory extend to other executive functions is not well understood. In the current study 38 children with a poor…

Initial Feasibility and Validity of a Prospective Memory Training Program in a Substance Use Treatment Population

PubMed Central

Sweeney, Mary M.; Rass, Olga; Johnson, Patrick S.; Strain, Eric C.; Berry, Meredith S.; Vo, Hoa T.; Fishman, Marc J.; Munro, Cynthia A.; Rebok, George W.; Mintzer, Miriam Z.; Johnson, Matthew W.

2016-01-01

Individuals with substance use disorders have shown deficits in the ability to implement future intentions, called prospective memory. Deficits in prospective memory and working memory, a critical underlying component of prospective memory, likely contribute to substance use treatment failures. Thus, improvement of prospective memory and working memory in substance use patients is an innovative target for intervention. We sought to develop a feasible and valid prospective memory training program that incorporates working memory training and may serve as a useful adjunct to substance use disorder treatment. We administered a single session of the novel prospective memory and working memory training program to participants (n = 22; 13 male; 9 female) enrolled in outpatient substance use disorder treatment and correlated performance to existing measures of prospective memory and working memory. Generally accurate prospective memory performance in a single session suggests feasibility in a substance use treatment population. However, training difficulty should be increased to avoid ceiling effects across repeated sessions. Consistent with existing literature, we observed superior performance on event-based relative to time-based prospective memory tasks. Performance on the prospective memory and working memory training components correlated with validated assessments of prospective memory and working memory, respectively. Correlations between novel memory training program performance and established measures suggest that our training engages appropriate cognitive processes. Further, differential event- and time-based prospective memory task performance suggests internal validity of our training. These data support development of this intervention as an adjunctive therapy for substance use disorders. PMID:27690506

Initial feasibility and validity of a prospective memory training program in a substance use treatment population.

PubMed

Sweeney, Mary M; Rass, Olga; Johnson, Patrick S; Strain, Eric C; Berry, Meredith S; Vo, Hoa T; Fishman, Marc J; Munro, Cynthia A; Rebok, George W; Mintzer, Miriam Z; Johnson, Matthew W

2016-10-01

Individuals with substance use disorders have shown deficits in the ability to implement future intentions, called prospective memory. Deficits in prospective memory and working memory, a critical underlying component of prospective memory, likely contribute to substance use treatment failures. Thus, improvement of prospective memory and working memory in substance use patients is an innovative target for intervention. We sought to develop a feasible and valid prospective memory training program that incorporates working memory training and may serve as a useful adjunct to substance use disorder treatment. We administered a single session of the novel prospective memory and working memory training program to participants (n = 22; 13 men, 9 women) enrolled in outpatient substance use disorder treatment and correlated performance to existing measures of prospective memory and working memory. Generally accurate prospective memory performance in a single session suggests feasibility in a substance use treatment population. However, training difficulty should be increased to avoid ceiling effects across repeated sessions. Consistent with existing literature, we observed superior performance on event-based relative to time-based prospective memory tasks. Performance on the prospective memory and working memory training components correlated with validated assessments of prospective memory and working memory, respectively. Correlations between novel memory training program performance and established measures suggest that our training engages appropriate cognitive processes. Further, differential event- and time-based prospective memory task performance suggests internal validity of our training. These data support the development of this intervention as an adjunctive therapy for substance use disorders. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Mental Imagery and Visual Working Memory

PubMed Central

Keogh, Rebecca; Pearson, Joel

2011-01-01

Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory - but not iconic visual memory - can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance diminished performance on visual working memory and imagery tasks, but not working memory for number strings. This suggests that luminance signals were disrupting sensory-based imagery mechanisms and not a general working memory system. Individuals with poor imagery still performed above chance in the visual working memory task, but their performance was not affected by the background luminance, suggesting a dichotomy in strategies for visual working memory: individuals with strong mental imagery rely on sensory-based imagery to support mnemonic performance, while those with poor imagery rely on different strategies. These findings could help reconcile current controversy regarding the mechanism and location of visual mnemonic storage. PMID:22195024

Mental imagery and visual working memory.

PubMed

Keogh, Rebecca; Pearson, Joel

2011-01-01

Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory--but not iconic visual memory--can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance diminished performance on visual working memory and imagery tasks, but not working memory for number strings. This suggests that luminance signals were disrupting sensory-based imagery mechanisms and not a general working memory system. Individuals with poor imagery still performed above chance in the visual working memory task, but their performance was not affected by the background luminance, suggesting a dichotomy in strategies for visual working memory: individuals with strong mental imagery rely on sensory-based imagery to support mnemonic performance, while those with poor imagery rely on different strategies. These findings could help reconcile current controversy regarding the mechanism and location of visual mnemonic storage.

A Comparison of Computation Span and Reading Span Working Memory Measures' Relations With Problem-Solving Criteria.

PubMed

Perlow, Richard; Jattuso, Mia

2018-06-01

Researchers have operationalized working memory in different ways and although working memory-performance relationships are well documented, there has been relatively less attention devoted to determining whether seemingly similar measures yield comparable relations with performance outcomes. Our objective is to assess whether two working memory measures deploying the same processes but different item content yield different relations with two problem-solving criteria. Participants completed a computation-based working memory measure and a reading-based measure prior to performing a computerized simulation. Results reveal differential relations with one of the two criteria and support the notion that the two working memory measures tap working memory capacity and other cognitive abilities. One implication for theory development is that researchers should consider incorporating other cognitive abilities in their working memory models and that the selection of those abilities should correspond to the criterion of interest. One practical implication is that researchers and practitioners shouldn't automatically assume that different phonological loop-based working memory scales are interchangeable.

Exploring the Effects of Working Memory on Time Perception in Attention Deficit Hyperactivity Disorder.

PubMed

Lee, Hom-Yi; Yang, En-Lin

2018-01-01

Children with attention deficit hyperactivity disorder (ADHD) are often reported to have deficits of time perception. However, there is a strong relation between performance on tasks of working memory and time perception. Thus, it is possible that the poor performance of children with ADHD on time perception results from their deficit of working memory. In this study, the working memory of participants was separately assessed; therefore, we could explore the relationship between working memory and time perception of children with ADHD. Fifty-six children with ADHD and those of healthy controls completed tasks measuring working memory and time perception. The results showed that the time discrimination ability of children with ADHD was poorer than that of controls. However, there was a strong association between time perception and working memory. After controlling working memory and intelligence, the time discrimination ability of children with ADHD was not significantly poorer than that of controls. We suggest that there is an interdependent relationship between time perception and working memory for children with ADHD.

Working memory, control of interference and everyday experience of thought interference: when age makes the difference.

PubMed

Borella, Erika; Carretti, Barbara; Cornoldi, Cesare; De Beni, Rossana

2007-06-01

A number of studies suggest that age differences in working memory may be attributed to age-related differences in inhibitory efficacy. Nevertheless, little is known about the impact of intrusive thoughts, which occurs in everyday situations on working memory performance. This study investigates the role of cognitive and everyday inhibition mechanisms in working memory performance. Young, young-old and old-old adults performed a working memory task and the White Bear Suppression Inventory (WBSI). Results showed a decrease in working memory, and in inhibitory efficacy with age. In addition, old-old adults obtained higher scores in the three factors of the WBSI. Working memory performance was related to working memory control of interfering information in all age groups, and also to the tendency to suppress thoughts in old-old adults. The latter result was in the opposite direction with respect to observations collected with younger adults. Taken together, our results suggest the crucial role of intrusive thoughts in the functional capacity of working memory in late adulthood.

Memory updating in sub-clinical eating disorder: differential effects with food and body shape words.

PubMed

Fenton, Olivia; Ecker, Ullrich K H

2015-04-01

The present study investigated how eating disorder (ED) relevant information is updated in working memory in people with high vs. low scores on a measure of eating disorder pathology (the Eating Disorder Examination Questionnaire, EDE-Q). Participants performed two memory updating tasks. One was a neutral control task using digits; the other task involved food words and words relating to body-shape, and provided measures of updating speed and post-updating recall. We found that high EDE-Q participants (1) showed no sign of general memory updating impairment as indicated by performance in the control task; (2) showed a general recall deficit in the task involving ED-relevant stimuli, suggesting a general distraction of cognitive resources in the presence of ED-related items; (3) showed a relative facilitation in the recall of food words; and (4) showed quicker updating toward food words and relatively slower updating toward body-shape-related words. Results are discussed in the context of cognitive theories of eating disorders. Copyright © 2015 Elsevier Ltd. All rights reserved.

Working memory is not fixed-capacity: More active storage capacity for real-world objects than for simple stimuli

PubMed Central

Brady, Timothy F.; Störmer, Viola S.; Alvarez, George A.

2016-01-01

Visual working memory is the cognitive system that holds visual information active to make it resistant to interference from new perceptual input. Information about simple stimuli—colors and orientations—is encoded into working memory rapidly: In under 100 ms, working memory ‟fills up,” revealing a stark capacity limit. However, for real-world objects, the same behavioral limits do not hold: With increasing encoding time, people store more real-world objects and do so with more detail. This boost in performance for real-world objects is generally assumed to reflect the use of a separate episodic long-term memory system, rather than working memory. Here we show that this behavioral increase in capacity with real-world objects is not solely due to the use of separate episodic long-term memory systems. In particular, we show that this increase is a result of active storage in working memory, as shown by directly measuring neural activity during the delay period of a working memory task using EEG. These data challenge fixed-capacity working memory models and demonstrate that working memory and its capacity limitations are dependent upon our existing knowledge. PMID:27325767

Working memory is not fixed-capacity: More active storage capacity for real-world objects than for simple stimuli.

PubMed

Brady, Timothy F; Störmer, Viola S; Alvarez, George A

2016-07-05

Visual working memory is the cognitive system that holds visual information active to make it resistant to interference from new perceptual input. Information about simple stimuli-colors and orientations-is encoded into working memory rapidly: In under 100 ms, working memory ‟fills up," revealing a stark capacity limit. However, for real-world objects, the same behavioral limits do not hold: With increasing encoding time, people store more real-world objects and do so with more detail. This boost in performance for real-world objects is generally assumed to reflect the use of a separate episodic long-term memory system, rather than working memory. Here we show that this behavioral increase in capacity with real-world objects is not solely due to the use of separate episodic long-term memory systems. In particular, we show that this increase is a result of active storage in working memory, as shown by directly measuring neural activity during the delay period of a working memory task using EEG. These data challenge fixed-capacity working memory models and demonstrate that working memory and its capacity limitations are dependent upon our existing knowledge.

Context controls access to working and reference memory in the pigeon (Columba livia).

PubMed

Roberts, William A; Macpherson, Krista; Strang, Caroline

2016-01-01

The interaction between working and reference memory systems was examined under conditions in which salient contextual cues were presented during memory retrieval. Ambient colored lights (red or green) bathed the operant chamber during the presentation of comparison stimuli in delayed matching-to-sample training (working memory) and during the presentation of the comparison stimuli as S+ and S- cues in discrimination training (reference memory). Strong competition between memory systems appeared when the same contextual cue appeared during working and reference memory training. When different contextual cues were used, however, working memory was completely protected from reference memory interference. © 2016 Society for the Experimental Analysis of Behavior.

Reliable gains? Evidence for substantially underpowered designs in studies of working memory training transfer to fluid intelligence.

PubMed

Bogg, Tim; Lasecki, Leanne

2014-01-01

In recent years, cognitive scientists and commercial interests (e.g., Fit Brains, Lumosity) have focused research attention and financial resources on cognitive tasks, especially working memory tasks, to explore and exploit possible transfer effects to general cognitive abilities, such as fluid intelligence. The increased research attention has produced mixed findings, as well as contention about the disposition of the evidence base. To address this contention, Au et al. (2014) recently conducted a meta-analysis of extant controlled experimental studies of n-back task training transfer effects on measures of fluid intelligence in healthy adults; the results of which showed a small training transfer effect. Using several approaches, the current review evaluated and re-analyzed the meta-analytic data for the presence of two different forms of small-study effects: (1) publication bias in the presence of low power and; (2) low power in the absence of publication bias. The results of these approaches showed no evidence of selection bias in the working memory training literature, but did show evidence of small-study effects related to low power in the absence of publication bias. While the effect size estimate identified by Au et al. (2014) provided the most precise estimate to date, it should be interpreted in the context of a uniformly low-powered base of evidence. The present work concludes with a brief set of considerations for assessing the adequacy of a body of research findings for the application of meta-analytic techniques.

Working memory and organizational skills problems in ADHD.

PubMed

Kofler, Michael J; Sarver, Dustin E; Harmon, Sherelle L; Moltisanti, Allison; Aduen, Paula A; Soto, Elia F; Ferretti, Nicole

2018-01-01

This study tested model-driven predictions regarding working memory's role in the organizational problems associated with ADHD. Children aged 8-13 (M = 10.33, SD = 1.42) with and without ADHD (N = 103; 39 girls; 73% Caucasian/Non-Hispanic) were assessed on multiple, counterbalanced working memory tasks. Parents and teachers completed norm-referenced measures of organizational problems (Children's Organizational Skills Scale; COSS). Results confirmed large magnitude working memory deficits (d = 1.24) and organizational problems in ADHD (d = 0.85). Bias-corrected, bootstrapped conditional effects models linked impaired working memory with greater parent- and teacher-reported inattention, hyperactivity/impulsivity, and organizational problems. Working memory predicted organization problems across all parent and teacher COSS subscales (R 2  = .19-.23). Approximately 38%-57% of working memory's effect on organization problems was conveyed by working memory's association with inattentive behavior. Unique effects of working memory remained significant for both parent- and teacher-reported task planning, as well as for teacher-reported memory/materials management and overall organization problems. Attention problems uniquely predicted worse organizational skills. Hyperactivity was unrelated to parent-reported organizational skills, but predicted better teacher-reported task planning. Children with ADHD exhibit multisetting, broad-based organizational impairment. These impaired organizational skills are attributable in part to performance deficits secondary to working memory dysfunction, both directly and indirectly via working memory's role in regulating attention. Impaired working memory in ADHD renders it extraordinarily difficult for these children to consistently anticipate, plan, enact, and maintain goal-directed actions. © 2017 Association for Child and Adolescent Mental Health.

The effects of autobiographical memory and visual perspective on working memory.

PubMed

Cheng, Zenghu; She, Yugui

2018-08-01

The present research aims to explore whether recalling and writing about autobiographical memory from different perspectives (first-person perspective vs. third-person perspective) could affect cognitive function. The participants first performed a working memory task to evaluate their working memory capacity as a baseline and then were instructed to recall (Study 1) or write about (Study 2) personal events (failures vs. successes) from the first-person perspective or the third-person perspective. Finally, they performed the working memory task again. The results suggested that autobiographical memory and perspective influence working memory interactively. When recalling a success, the participants who recalled from the third-person perspective performed better than those who recalled from the first-person perspective on the working memory capacity task; when recalling a failure, the opposite was true.

Verbal working memory performance correlates with regional white matter structures in the frontoparietal regions.

PubMed

Takeuchi, Hikaru; Taki, Yasuyuki; Sassa, Yuko; Hashizume, Hiroshi; Sekiguchi, Atsushi; Fukushima, Ai; Kawashima, Ryuta

2011-10-01

Working memory is the limited capacity storage system involved in the maintenance and manipulation of information over short periods of time. Previous imaging studies have suggested that the frontoparietal regions are activated during working memory tasks; a putative association between the structure of the frontoparietal regions and working memory performance has been suggested based on the analysis of individuals with varying pathologies. This study aimed to identify correlations between white matter and individual differences in verbal working memory performance in normal young subjects. We performed voxel-based morphometry (VBM) analyses using T1-weighted structural images as well as voxel-based analyses of fractional anisotropy (FA) using diffusion tensor imaging. Using the letter span task, we measured verbal working memory performance in normal young adult men and women (mean age, 21.7 years, SD=1.44; 42 men and 13 women). We observed positive correlations between working memory performance and regional white matter volume (rWMV) in the frontoparietal regions. In addition, FA was found to be positively correlated with verbal working memory performance in a white matter region adjacent to the right precuneus. These regions are consistently recruited by working memory. Our findings suggest that, among normal young subjects, verbal working memory performance is associated with various regions that are recruited during working memory tasks, and this association is not limited to specific parts of the working memory network. Copyright © 2011 Elsevier Ltd. All rights reserved.

Memory Retrieval and Interference: Working Memory Issues

ERIC Educational Resources Information Center

Radvansky, Gabriel A.; Copeland, David E.

2006-01-01

Working memory capacity has been suggested as a factor that is involved in long-term memory retrieval, particularly when that retrieval involves a need to overcome some sort of interference (Bunting, Conway, & Heitz, 2004; Cantor & Engle, 1993). Previous work has suggested that working memory is related to the acquisition of information during…

Not only … but also: REM sleep creates and NREM Stage 2 instantiates landmark junctions in cortical memory networks.

PubMed

Llewellyn, Sue; Hobson, J Allan

2015-07-01

This article argues both rapid eye movement (REM) and non-rapid eye movement (NREM) sleep contribute to overnight episodic memory processes but their roles differ. Episodic memory may have evolved from memory for spatial navigation in animals and humans. Equally, mnemonic navigation in world and mental space may rely on fundamentally equivalent processes. Consequently, the basic spatial network characteristics of pathways which meet at omnidirectional nodes or junctions may be conserved in episodic brain networks. A pathway is formally identified with the unidirectional, sequential phases of an episodic memory. In contrast, the function of omnidirectional junctions is not well understood. In evolutionary terms, both animals and early humans undertook tours to a series of landmark junctions, to take advantage of resources (food, water and shelter), whilst trying to avoid predators. Such tours required memory for emotionally significant landmark resource-place-danger associations and the spatial relationships amongst these landmarks. In consequence, these tours may have driven the evolution of both spatial and episodic memory. The environment is dynamic. Resource-place associations are liable to shift and new resource-rich landmarks may be discovered, these changes may require re-wiring in neural networks. To realise these changes, REM may perform an associative, emotional encoding function between memory networks, engendering an omnidirectional landmark junction which is instantiated in the cortex during NREM Stage 2. In sum, REM may preplay associated elements of past episodes (rather than replay individual episodes), to engender an unconscious representation which can be used by the animal on approach to a landmark junction in wake. Copyright © 2015 Elsevier Inc. All rights reserved.

Processing speed and working memory span: their differential role in superficial and deep memory processes in schizophrenia.

PubMed

Brébion, Gildas; Bressan, Rodrigo A; Pilowsky, Lyn S; David, Anthony S

2011-05-01

Previous work has suggested that decrement in both processing speed and working memory span plays a role in the memory impairment observed in patients with schizophrenia. We undertook a study to examine simultaneously the effect of these two factors. A sample of 49 patients with schizophrenia and 43 healthy controls underwent a battery of verbal and visual memory tasks. Superficial and deep encoding memory measures were tallied. We conducted regression analyses on the various memory measures, using processing speed and working memory span as independent variables. In the patient group, processing speed was a significant predictor of superficial and deep memory measures in verbal and visual memory. Working memory span was an additional significant predictor of the deep memory measures only. Regression analyses involving all participants revealed that the effect of diagnosis on all the deep encoding memory measures was reduced to non-significance when processing speed was entered in the regression. Decreased processing speed is involved in verbal and visual memory deficit in patients, whether the task require superficial or deep encoding. Working memory is involved only insofar as the task requires a certain amount of effort.