scholarly journals Dopamine Alters the Fidelity of Working Memory Representations according to Attentional Demands

2017 ◽  
Vol 29 (4) ◽  
pp. 728-738 ◽  
Author(s):  
Sean James Fallon ◽  
Nahid Zokaei ◽  
Agnes Norbury ◽  
Sanjay G. Manohar ◽  
Masud Husain
Keyword(s):  
Working Memory ◽  
Stochastic Model ◽  
Receptor Agonist ◽  
Response Selection ◽  
Recall Performance ◽  
Drug Induced ◽  
Capacity Limitations ◽  
Significant Difference ◽  
Memory Representations ◽  
Induced Changes

Capacity limitations in working memory (WM) necessitate the need to effectively control its contents. Here, we examined the effect of cabergoline, a dopamine D2 receptor agonist, on WM using a continuous report paradigm that allowed us to assess the fidelity with which items are stored. We assessed recall performance under three different gating conditions: remembering only one item, being cued to remember one target among distractors, and having to remember all items. Cabergoline had differential effects on recall performance according to whether distractors had to be ignored and whether mnemonic resources could be deployed exclusively to the target. Compared with placebo, cabergoline improved mnemonic performance when there were no distractors but significantly reduced performance when distractors were presented in a precue condition. No significant difference in performance was observed under cabergoline when all items had to be remembered. By applying a stochastic model of response selection, we established that the causes of drug-induced changes in performance were due to changes in the precision with which items were stored in WM. However, there was no change in the extent to which distractors were mistaken for targets. Thus, D2 agonism causes changes in the fidelity of mnemonic representations without altering interference between memoranda.

A direct neural measure of variable precision representations in visual working memory

2021 ◽  
Author(s):  
Christian Merkel ◽  
Mandy Viktoria Bartsch ◽  
Mircea A Schoenfeld ◽  
Anne-Katrin Vellage ◽  
Notger G Müller ◽  
...  
Keyword(s):  
Working Memory ◽  
Visual Working Memory ◽  
Recall Performance ◽  
Human Subjects ◽  
Item Information ◽  
Estimation Task ◽  
Active Representation ◽  
Contralateral Delay Activity ◽  
Memory Representations ◽  
Precision Estimation

Visual working memory (VWM) is an active representation enabling the manipulation of item information even in the absence of visual input. A common way to investigate VWM is to analyze the performance at later recall. This approach, however, leaves uncertainties about whether the variation of recall performance is attributable to item encoding and maintenance or to the testing of memorized information. Here, we record the contralateral delay activity (CDA) - an established electrophysiological measure of item storage and maintenance - in human subjects performing a delayed orientation precision estimation task. This allows us to link the fluctuation of recall precision directly to the process of item encoding and maintenance. We show that for two sequentially encoded orientation items, the CDA amplitude reflects the precision of orientation recall of both items, with higher precision being associated with a larger amplitude. Furthermore, we show that the CDA amplitude for each item varies independently from each other, suggesting that the precision of memory representations fluctuates independently.

scholarly journals Effects of Working Memory Demand on Neural Mechanisms of Motor Response Selection and Control

2013 ◽  
Vol 25 (8) ◽  
pp. 1235-1248 ◽  
Author(s):  
Anita D. Barber ◽  
Brian S. Caffo ◽  
James J. Pekar ◽  
Stewart H. Mostofsky
Keyword(s):  
Working Memory ◽  
Inhibitory Control ◽  
Response Selection ◽  
Inferior Frontal Gyrus ◽  
Stimulus Response ◽  
Control Functions ◽  
Dorsolateral Prefrontal ◽  
Memory Representations ◽  
And Control ◽  
Inferior Frontal Junction

Inhibitory control commonly recruits a number of frontal regions: pre-supplementary motor area (pre-SMA), frontal eye fields (FEFs), and right-lateralized posterior inferior frontal gyrus (IFG), dorsal anterior insula (DAI), dorsolateral prefrontal cortex (DLPFC), and inferior frontal junction (IFJ). These regions may directly implement inhibitory motor control or may be more generally involved in executive control functions. Two go/no-go tasks were used to distinguish regions specifically recruited for inhibition from those that additionally show increased activity with working memory demand. The pre-SMA and IFG were recruited for inhibition in both tasks and did not have greater activation for working memory demand on no-go trials, consistent with a role in inhibitory control. Activation in pre-SMA also responded to response selection demand and was increased with working memory on go trials specifically. The bilateral FEF and right DAI were commonly active for no-go trials. The FEF was also recruited to a greater degree with working memory demand on go trials and may bias top–down information when stimulus–response mappings change. The DAI, additionally responded to increased working memory demand on both go and no-go trials and may be involved in accessing sustained task information, alerting, or autonomic changes when cognitive demands increase. DLPFC activation was consistent with a role in working memory retrieval on both go and no-go trials. The inferior frontal junction, on the other hand, had greater activation with working memory specifically for no-go trials and may detect salient stimuli when the task requires frequent updating of working memory representations.

Effects of Visual and Aural Presentation Styles and Rhythm on Working Memory as Measured by Monosyllabic Sequential Digit Recall

2020 ◽  
pp. 003329412093097
Author(s):  
Michael J. Silverman ◽  
Sonia W. Bourdaghs ◽  
Edward T. Schwartzberg
Keyword(s):  
Working Memory ◽  
Recall Performance ◽  
Basic Research ◽  
Future Research ◽  
Presentation Style ◽  
Presentation Modes ◽  
Visual Rhythm ◽  
Significant Difference ◽  
Nonmusic Majors ◽  
Digit Recall

Although information is frequently paired with music to enhance recall, there is a lack of basic research investigating how aspects of recorded music, as well as how it is presented, facilitate working memory. Therefore, the purpose of this study was to determine the effects of visual and aural presentation styles, rhythm, and participant major on working memory as measured by sequential monosyllabic digit recall performance. We isolated visual and aural presentation styles and rhythm conditions during six different treatment stimuli presented on a computer screen in the study: (a) Visual Rhythm; (b) Visual No Rhythm; (c) Aural Rhythm; (d) Aural No Rhythm; (e) Visual + Aural Rhythm; (f) Visual + Aural No Rhythm. Participants’ ( N = 60; 30 nonmusic majors and 30 music majors) task was to immediately recall the information paired with music within each condition. Analyses of variance indicated a significant difference between the visual and visual + aural presentation style conditions with the visual + aural condition having more accurate recall. While descriptive data indicated that rhythm tended to facilitate recall, there was no significant difference between rhythm and no rhythm conditions. Nonmusic major participants tended to have slightly more accurate recall than music major participants, although this difference was not significant. Participants tended to have higher recall accuracy during primacy and recency serial positions. As participants had most accurate recall during the visual + aural presentation style conditions, it seems that the multi-sensory presentation modes can be effective for teaching information to be immediately recalled as long as they do not contain too much information and overload the limited storage capacity of working memory. Implications for clinical practice, limitations, and suggestions for future research are provided.

Effects of Visual and Auditory Presentation Styles and Musical Elements on Working Memory as Measured by Monosyllabic Sequential Digit Recall

2018 ◽  
Vol 122 (4) ◽  
pp. 1297-1312 ◽  
Author(s):  
Michael J. Silverman ◽  
Edward T. Schwartzberg
Keyword(s):  
Working Memory ◽  
Recall Performance ◽  
Basic Research ◽  
Auditory Presentation ◽  
Future Research ◽  
Auditory Condition ◽  
Auditory Speech ◽  
Significant Difference ◽  
Digit Recall ◽  
Musical Elements

Information is often paired with music to facilitate memory and learning. However, there is a lack of basic research investigating how visual and auditory presentation styles and musical elements might facilitate recall. The purpose of this study is to isolate and determine the effects of visual and auditory presentation styles and musical elements on working memory as measured by sequential monosyllabic digit recall performance. Recall was tested on 60 undergraduate university students during six different conditions: (a) Visual + Auditory Chant, (b) Visual + Auditory Melody, (c) Visual + Auditory Speech, (d) Auditory Chant, (e) Auditory Melody, and (f) Auditory Speech. There was a significant interaction between presentation style and musical element conditions. There were significant differences between auditory and visual + auditory conditions in the melody and speech conditions but not in the chant condition. In all cases, the auditory condition had more accurate recall than the visual + auditory condition, with recall differences largest during the speech condition. There was no significant difference between chant and melody but significant differences between chant and speech and melody and speech in the visual + auditory condition. In the auditory condition, recall accuracy was lower for speech than for melody or chant. There was no significant difference between chant and melody, chant and speech, or melody and speech in the visual + auditory condition. Congruent with existing research, the addition of visual input likely overloaded working memory resulting in worse recall. Implications for clinical practice, limitations, and suggestions for future research are provided.

Drug Induced Changes in Cell Organelles

1968 ◽  
Vol 26 ◽  
pp. 110-111
Author(s):  
Sarah A. Luse
Keyword(s):  
Clinical Medicine ◽  
Cell Organelles ◽  
Riboflavin Deficiency ◽  
Drug Induced ◽  
New Era ◽  
Health And Disease ◽  
In The Beginning ◽  
Cellular Pathology ◽  
Induced Changes ◽  
The Impact

In the mid-nineteenth century Virchow revolutionized pathology by introduction of the concept of “cellular pathology”. Today, a century later, this term has increasing significance in health and disease. We now are in the beginning of a new era in pathology, one which might well be termed “organelle pathology” or “subcellular pathology”. The impact of lysosomal diseases on clinical medicine exemplifies this role of pathology of organelles in elucidation of disease today.Another aspect of cell organelles of prime importance is their pathologic alteration by drugs, toxins, hormones and malnutrition. The sensitivity of cell organelles to minute alterations in their environment offers an accurate evaluation of the site of action of drugs in the study of both function and toxicity. Examples of mitochondrial lesions include the effect of DDD on the adrenal cortex, riboflavin deficiency on liver cells, elevated blood ammonia on the neuron and some 8-aminoquinolines on myocardium.

Transient Working Memory Representations That Govern Intentional S-R Translation

2007 ◽  
Author(s):  
Nachshon Meiran ◽  
Yoav Kessler ◽  
Oshrit Cohen-Kdoshai ◽  
Ravid Elenbogen
Keyword(s):  
Working Memory ◽  
Memory Representations

Attentional Guidance from Activated and Inhibitory States of Working Memory Representations

2015 ◽  
Vol 47 (9) ◽  
pp. 1089
Author(s):  
Bao ZHANG ◽  
Jiaying SHAO ◽  
Cenlou HU ◽  
Sai Huang
Keyword(s):  
Working Memory ◽  
Attentional Guidance ◽  
Memory Representations

Automatic and Strategic Processes in Advertising Effects

1996 ◽  
Vol 60 (4) ◽  
pp. 88-101 ◽  
Author(s):  
Klaus G. Grunert
Keyword(s):  
Working Memory ◽  
Cognitive Processes ◽  
Automatic Processes ◽  
Relative Importance ◽  
Product Involvement ◽  
High Involvement ◽  
Capacity Limitations ◽  
Brand Evaluation ◽  
Advertising Effects ◽  
Strategic Processes

The author distinguishes two kinds of cognitive processes: automatic processes, which are mostly subconscious, are learned and changed slowly and are not subject to the capacity limitations of working memory, and strategic processes, which are conscious, are subject to capacity limitations, and can easily be adapted to situational circumstances. The perception of advertising and the way it influences brand evaluation involves both processes. Automatic processes govern the recognition of advertising stimuli, the relevance decision that determines further higher-level processing, the retrieval of information, and the provision of a heuristic for brand evaluation. Strategic processes govern learning and inference formation. The relative importance of both types of processes depends on product involvement. The distinction of these two types of processes leads to some conclusions that are at variance with current notions about advertising effects. For example, the attention span problem is relevant only for strategic processes. A certain amount of learning can occur with little conscious effort, and advertising's effect on brand evaluation may be more stable for low- than for high-involvement products.

scholarly journals Working memory deficits in schizophrenia are associated with the rs34884856 variant and expression levels of the NR4A2 gene in a sample Mexican population: a case control study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Elizabeth Ruiz-Sánchez ◽  
Janet Jiménez-Genchi ◽  
Yessica M. Alcántara-Flores ◽  
Carlos J. Castañeda-González ◽  
Carlos L. Aviña-Cervantes ◽  
...  
Keyword(s):  
Working Memory ◽  
Genetic Variants ◽  
Mononuclear Cells ◽  
Memory Performance ◽  
Mexican Population ◽  
High Resolution Melt ◽  
Expression Levels ◽  
Neuropsychiatric Diseases ◽  
Significant Difference ◽  
Peripheral Mononuclear Cells

Abstract Background Cognitive functions represent useful endophenotypes to identify the association between genetic variants and schizophrenia. In this sense, the NR4A2 gene has been implicated in schizophrenia and cognition in different animal models and clinical trials. We hypothesized that the NR4A2 gene is associated with working memory performance in schizophrenia. This study aimed to analyze two variants and the expression levels of the NR4A2 gene with susceptibility to schizophrenia, as well as to evaluate whether possession of NR4A2 variants influence the possible correlation between gene expression and working memory performance in schizophrenia. Methods The current study included 187 schizophrenia patients and 227 controls genotyped for two of the most studied NR4A2 genetic variants in neurological and neuropsychiatric diseases. Genotyping was performed using High Resolution Melt and sequencing techniques. In addition, mRNA expression of NR4A2 was performed in peripheral mononuclear cells of 112 patients and 118 controls. A group of these participants, 54 patients and 87 controls, performed the working memory index of the WAIS III test. Results Both genotypic frequencies of the two variants and expression levels of the NR4A2 gene showed no significant difference when in patients versus controls. However, patients homozygous for the rs34884856 promoter variant showed a positive correlation between expression levels and auditory working memory. Conclusions Our finding suggested that changes in expression levels of the NR4A2 gene could be associated with working memory in schizophrenia depending on patients’ genotype in a sample from a Mexican population.

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