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Herzog N, Hartmann H, Janssen LK, Waltmann M, Fallon SJ, Deserno L, Horstmann A. Working memory gating in obesity: Insights from a case-control fMRI study. Appetite 2024; 195:107179. [PMID: 38145879 DOI: 10.1016/j.appet.2023.107179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 12/08/2023] [Accepted: 12/18/2023] [Indexed: 12/27/2023]
Abstract
Computational models and neurophysiological data propose that a 'gating mechanism' coordinates distractor-resistant maintenance and flexible updating of working memory contents: While maintenance of information is mainly implemented in the prefrontal cortex, updating of information is signaled by phasic increases in dopamine in the striatum. Previous literature demonstrates structural and functional alterations in these brain areas, as well as differential dopamine transmission among individuals with obesity, suggesting potential impairments in these processes. To test this hypothesis, we conducted an observational case-control fMRI study, dividing participants into groups with and without obesity based on their BMI. We probed maintenance and updating of working memory contents using a modified delayed match to sample task and investigated the effects of SNPs related to the dopaminergic system. While the task elicited the anticipated brain responses, our findings revealed no evidence for group differences in these two processes, neither at the neural level nor behaviorally. However, depending on Taq1A genotype, which affects dopamine receptor density in the striatum, participants with obesity performed worse on the task. In conclusion, this study does not support the existence of overall obesity-related differences in working memory gating. Instead, we propose that potentially subtle alterations may manifest specifically in individuals with a 'vulnerable' genotype.
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Affiliation(s)
- Nadine Herzog
- Department of Neurology, Max Planck Institute for Human Cognitive & Brain Sciences, Leipzig, Germany.
| | - Hendrik Hartmann
- Department of Neurology, Max Planck Institute for Human Cognitive & Brain Sciences, Leipzig, Germany; Collaborative Research Centre 1052, University of Leipzig, Leipzig, Germany; Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Lieneke K Janssen
- Department of Neurology, Max Planck Institute for Human Cognitive & Brain Sciences, Leipzig, Germany; Institute of Psychology, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - Maria Waltmann
- Department of Neurology, Max Planck Institute for Human Cognitive & Brain Sciences, Leipzig, Germany; School of Psychology, University of Plymouth, Plymouth, UK
| | - Sean J Fallon
- School of Psychology, University of Plymouth, Plymouth, UK
| | - Lorenz Deserno
- Department of Child and Adolescent Psychiatry, University of Würzburg, Würzburg, Germany
| | - Annette Horstmann
- Department of Neurology, Max Planck Institute for Human Cognitive & Brain Sciences, Leipzig, Germany; Collaborative Research Centre 1052, University of Leipzig, Leipzig, Germany; Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki, Finland
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2
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Fallon SJ, Plant O, Tabi YA, Manohar SG, Husain M. Effects of cholinesterase inhibition on attention and working memory in Lewy body dementias. Brain Commun 2023; 5:fcad207. [PMID: 37545547 PMCID: PMC10404008 DOI: 10.1093/braincomms/fcad207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 05/23/2023] [Accepted: 07/25/2023] [Indexed: 08/08/2023] Open
Abstract
Cholinesterase inhibitors are frequently used to treat cognitive symptoms in Lewy body dementias (Parkinson's disease dementia and dementia with Lewy bodies). However, the selectivity of their effects remains unclear. In a novel rivastigmine withdrawal design, Parkinson's disease dementia and dementia with Lewy bodies patients were tested twice: once when taking rivastigmine as usual and once when they had missed one dose. In each session, they performed a suite of tasks (sustained attention, simple short-term recall, distractor resistance and manipulating the focus of attention) that allowed us to investigate the cognitive mechanisms through which rivastigmine affects attentional control. Consistent with previous literature, rivastigmine withdrawal significantly impaired attentional efficacy (quicker response latencies without a change in accuracy). However, it had no effects on cognitive control as assessed by the ability to withhold a response (inhibitory control). Worse short-term memory performance was also observed when patients were OFF rivastigmine, but these effects were delay and load independent, likely due to impaired visual attention. In contrast to previous studies that have examined the effects of dopamine withdrawal, cognitively complex tasks requiring control over the contents of working memory (ignoring, updating or shifting the focus of attention) were not significantly impaired by rivastigmine withdrawal. Cumulatively, these data support that the conclusion that cholinesterase inhibition has relatively specific and circumscribed-rather than global-effects on attention that may also affect performance on simple short-term memory tasks, but not when cognitive control over working memory is required. The results also indicate that the withdrawal of a single dose of rivastigmine is sufficient to reveal these impairments, demonstrating that cholinergic withdrawal can be an informative clinical as well as an investigative tool.
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Affiliation(s)
- Sean James Fallon
- Department of Experimental Psychology, University of Oxford, Oxford OX2 6GG, UK
- School of Psychology, University of Plymouth, Plymouth PL4 8AA, UK
| | - Olivia Plant
- Department of Experimental Psychology, University of Oxford, Oxford OX2 6GG, UK
| | - Younes A Tabi
- Department of Experimental Psychology, University of Oxford, Oxford OX2 6GG, UK
| | - Sanjay G Manohar
- Department of Experimental Psychology, University of Oxford, Oxford OX2 6GG, UK
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Masud Husain
- Department of Experimental Psychology, University of Oxford, Oxford OX2 6GG, UK
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford OX3 9DU, UK
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Hartmann H, Janssen LK, Herzog N, Morys F, Fängström D, Fallon SJ, Horstmann A. Self-reported intake of high-fat and high-sugar diet is not associated with cognitive stability and flexibility in healthy men. Appetite 2023; 183:106477. [PMID: 36764221 DOI: 10.1016/j.appet.2023.106477] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 01/19/2023] [Accepted: 01/27/2023] [Indexed: 02/11/2023]
Abstract
Animal studies indicate that a high-fat/high-sugar diet (HFS) can change dopamine signal transmission in the brain, which could promote maladaptive behavior and decision-making. Such diet-induced changes may also explain observed alterations in the dopamine system in human obesity. Genetic variants that modulate dopamine transmission have been proposed to render some individuals more prone to potential effects of HFS. The objective of this study was to investigate the association of HFS with dopamine-dependent cognition in humans and how genetic variations might modulate this potential association. Using a questionnaire assessing the self-reported consumption of high-fat/high-sugar foods, we investigated the association with diet by recruiting healthy young men that fall into the lower or upper end of that questionnaire (low fat/sugar group: LFS, n = 45; high fat/sugar group: HFS, n = 41) and explored the interaction of fat and sugar consumption with COMT Val158Met and Taq1A genotype. During functional magnetic resonance imaging (fMRI) scanning, male participants performed a working memory (WM) task that probes distractor-resistance and updating of WM representations. Logistic and linear regression models revealed no significant difference in WM performance between the two diet groups, nor an interaction with COMT Val158Met or Taq1A genotype. Neural activation in task-related brain areas also did not differ between diet groups. Independent of diet group, higher BMI was associated with lower overall accuracy on the WM task. This cross-sectional study does not provide evidence for diet-related differences in WM stability and flexibility in men, nor for a predisposition of COMT Val158Met or Taq1A genotype to the hypothesized detrimental effects of an HFS diet. Previously reported associations of BMI with WM seem to be independent of HFS intake in our male study sample.
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Affiliation(s)
- Hendrik Hartmann
- Collaborative Research Centre 1052, University of Leipzig, Leipzig, Germany; Department of Neurology, Max Planck Institute for Human Cognitive & Brain Sciences, Leipzig, Germany; Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
| | - Lieneke K Janssen
- Collaborative Research Centre 1052, University of Leipzig, Leipzig, Germany; Institute of Psychology, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - Nadine Herzog
- Department of Neurology, Max Planck Institute for Human Cognitive & Brain Sciences, Leipzig, Germany
| | - Filip Morys
- Montreal Neurological Institute, Montreal, QC, Canada
| | - Daniel Fängström
- Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | | | - Annette Horstmann
- Collaborative Research Centre 1052, University of Leipzig, Leipzig, Germany; Department of Neurology, Max Planck Institute for Human Cognitive & Brain Sciences, Leipzig, Germany; Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki, Finland
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4
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Mercer T, Shaw R, Fisher L. Sources and mechanisms of modality-specific distraction in visual short-term memory. VISUAL COGNITION 2023. [DOI: 10.1080/13506285.2022.2162174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Tom Mercer
- School of Psychology, University of Wolverhampton, Wolverhampton, UK
| | - Raegan Shaw
- School of Psychology, University of Wolverhampton, Wolverhampton, UK
| | - Luke Fisher
- School of Psychology, Aston University, Birmingham, UK
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5
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Fallon SJ, van Rhee C, Kienast A, Manohar SG, Husain M. Mechanisms underlying corruption of working memory in Parkinson's disease. J Neuropsychol 2023. [PMID: 36642965 DOI: 10.1111/jnp.12306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 11/15/2022] [Accepted: 12/05/2022] [Indexed: 01/17/2023]
Abstract
Working memory (WM) impairments are reported to occur in patients with Parkinson's disease (PD). However, the mechanisms are unclear. Here, we investigate several putative factors that might drive poor performance, by examining the precision of recall, the order in which items are recalled and whether memories are corrupted by random guessing (attentional lapses). We used two separate tasks that examined the quality of WM recall under different loads and retention periods, as well as a traditional digit span test. Firstly, on a simple measure of WM recall, where patients were asked to reproduce the orientation of a centrally presented arrow, overall recall was not significantly impaired. However, there was some evidence for increased guessing (attentional lapses). On a new analogue version of the Corsi-span task, where participants had to reproduce on a touchscreen the exact spatial pattern of presented stimuli in the order and locations in which they appeared, there was a reduction in the precision of spatial WM at higher loads. This deficit was due to misremembering item order. At the highest load, there was reduced recall precision, whereas increased guessing was only observed at intermediate set sizes. Finally, PD patients had impaired backward, but not forward, digit spans. Overall, these results reveal the task- and load-dependent nature of WM deficits in PD. On simple low-load tasks, attentional lapses predominate, whereas at higher loads, in the spatial domain, the corruption of mnemonic information-both order item and precision-emerge as the main driver of impairment.
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Affiliation(s)
- Sean James Fallon
- Department of Experimental Psychology, University of Oxford, Oxford, UK.,School of Psychology, University of Plymouth, Plymouth, UK
| | - Chevonne van Rhee
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Annika Kienast
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Sanjay G Manohar
- Department of Experimental Psychology, University of Oxford, Oxford, UK.,Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK
| | - Masud Husain
- Department of Experimental Psychology, University of Oxford, Oxford, UK.,Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK
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6
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Tabi YA, Maio MR, Fallon SJ, Udale R, Dickson S, Idris MI, Nobis L, Manohar SG, Husain M. Impact of processing demands at encoding, maintenance and retrieval in visual working memory. Cognition 2021; 214:104758. [PMID: 33984741 PMCID: PMC8346950 DOI: 10.1016/j.cognition.2021.104758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 04/27/2021] [Accepted: 04/28/2021] [Indexed: 11/29/2022]
Abstract
There has been surprisingly little examination of how recall performance is affected by processing demands induced by retrieval cues, how manipulations at encoding interact with processing demands during maintenance or due to the retrieval cue, and how these are affected with aging. Here, we investigate these relationships by examining the fidelity of working memory recall across two delayed reproduction tasks with a continuous measure of report across the adult lifespan. Participants were asked to remember and subsequently reproduce from memory the identity and location of a probed item from the encoding display. In Experiment 1, we examined the effect of filtering irrelevant information at encoding and the impact of filtering distracting information at retrieval simultaneously. In Experiment 2, we tested how ignoring distracting information during maintenance or updating current contents with new information during this period affects recall. The results reveal that manipulating processing requirements induced by retrieval cues (by altering the nature of the retrieval foil) had a significant impact on memory recall: the presence of two previously viewed features from the encoding display in the retrieval foil led to a decrease in identification accuracy. Although irrelevant information can be filtered out well at encoding, both ignoring irrelevant information and updating the contents of memory during the maintenance delay had a detrimental effect on recall. These effects were similar across the lifespan, but older individuals were particularly affected by manipulations of processing demands at encoding as well as increasing set size of information to be retained in memory. Finally, analyses revealed that there were no systematic relationships between filtering performance at encoding, maintenance and retrieval suggesting that these processing demands are independent of each other. Rather than filtering being a single, monolithic entity, the data suggest that it is better accounted for as distinctly dissociable cognitive processes that engage and articulate with different phases of working memory.
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Affiliation(s)
- Younes Adam Tabi
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK; Department of Experimental Psychology, University of Oxford, Oxford, UK.
| | - Maria Raquel Maio
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK; Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Sean James Fallon
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Robert Udale
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Shannon Dickson
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Mohamad Imran Idris
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK
| | - Lisa Nobis
- Department of Psychiatry, University of Oxford, Oxford, UK
| | - Sanjay G Manohar
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK; Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Masud Husain
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK; Department of Experimental Psychology, University of Oxford, Oxford, UK; NIHR Oxford Biomedical Research Centre, Oxford, UK; Wellcome Centre for Integrative Neuroimaging, Oxford, UK
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7
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Grogan JP, Fallon SJ, Zokaei N, Husain M, Coulthard EJ, Manohar SG. A new toolbox to distinguish the sources of spatial memory error. J Vis 2020; 20:6. [PMID: 33289797 PMCID: PMC7726590 DOI: 10.1167/jov.20.13.6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 10/23/2020] [Indexed: 12/01/2022] Open
Abstract
Studying the sources of errors in memory recall has proven invaluable for understanding the mechanisms of working memory (WM). While one-dimensional memory features (e.g., color, orientation) can be analyzed using existing mixture modeling toolboxes to separate the influence of imprecision, guessing, and misbinding (the tendency to confuse features that belong to different memoranda), such toolboxes are not currently available for two-dimensional spatial WM tasks. Here we present a method to isolate sources of spatial error in tasks where participants have to report the spatial location of an item in memory, using two-dimensional mixture models. The method recovers simulated parameters well and is robust to the influence of response distributions and biases, as well as number of nontargets and trials. To demonstrate the model, we fit data from a complex spatial WM task and show the recovered parameters correspond well with previous spatial WM findings and with recovered parameters on a one-dimensional analogue of this task, suggesting convergent validity for this two-dimensional modeling approach. Because the extra dimension allows greater separation of memoranda and responses, spatial tasks turn out to be much better for separating misbinding from imprecision and guessing than one-dimensional tasks. Code for these models is freely available in the MemToolbox2D package and is integrated to work with the commonly used MATLAB package MemToolbox.
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Affiliation(s)
- John P Grogan
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Sean J Fallon
- Population Health Sciences, University of Bristol, Bristol, UK
| | - Nahid Zokaei
- Department of Experimental Psychology, University of Oxford, Oxford, UK
- Oxford Centre for Human Brain Activity, University of Oxford, Oxford, UK
| | - Masud Husain
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Elizabeth J Coulthard
- Translational Health Sciences, University of Bristol, Bristol, UK
- North Bristol NHS Trust, Bristol, UK
| | - Sanjay G Manohar
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- Oxford Centre for Human Brain Activity, University of Oxford, Oxford, UK
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8
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The effect of emotional primes on attentional focus in high versus low depression. Atten Percept Psychophys 2020; 82:377-382. [DOI: 10.3758/s13414-019-01833-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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9
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Fallon SJ, Gowell M, Maio MR, Husain M. Dopamine affects short-term memory corruption over time in Parkinson's disease. NPJ Parkinsons Dis 2019; 5:16. [PMID: 31396548 PMCID: PMC6683156 DOI: 10.1038/s41531-019-0088-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 06/25/2019] [Indexed: 11/09/2022] Open
Abstract
Cognitive deficits are a recognised component of Parkinson's disease (PD). However, particularly within the domain of short-term memory, it is unclear whether these impairments are masked, or caused, by patients' dopaminergic medication. The effect of medication on pure maintenance in PD patients has rarely been explored, with most assessments examining maintenance intercalated between other executive tasks. Moreover, few studies have utilised methods that can measure the quality of mental representations, which can enable the decomposition of recall errors into their underlying neurocognitive components. Here, we fill this gap by examining pure maintenance in PD patients in high and low dopaminergic states. Participants had to encode the orientation of two stimuli and reproduce these orientations after a short (2 s) or long (8 s) delay. In addition, we also examined the performance of healthy, age-matched older adults to contextualise these effects and determine whether PD represents an exacerbation of the normal ageing process. Patients showed improved recall OFF compared to ON their dopaminergic medication, but only for long-duration trials. Moreover, PD patients OFF their medication actually performed at a level superior to age-matched controls, indicative of a paradoxical enhancement of memory in the low dopaminergic state. The application of a probabilistic model of response selection suggested that PD patients made fewer misbinding errors in the low, compared with high, dopaminergic state for longer-delay trials. Thus, unexpectedly, the mechanisms that prevent memoranda from being corrupted by misbinding over time appear to be enhanced in PD patients OFF dopaminergic medication. Possible explanations for this paradoxical effect are discussed.
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Affiliation(s)
- Sean James Fallon
- Department of Experimental Psychology, University of Oxford, Oxford, UK
- National Institute for Health Research Bristol Biomedical Research Centre, University Hospitals Bristol NHS Foundation Trust and University of Bristol, Bristol, UK
| | - Matthew Gowell
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Maria Raquel Maio
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Masud Husain
- Department of Experimental Psychology, University of Oxford, Oxford, UK
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK
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Fallon SJ, Muhammed K, Drew DS, Ang YS, Manohar SG, Husain M. Dopamine guides competition for cognitive control: Common effects of haloperidol on working memory and response conflict. Cortex 2018; 113:156-168. [PMID: 30660954 DOI: 10.1016/j.cortex.2018.11.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 10/10/2018] [Accepted: 11/27/2018] [Indexed: 01/26/2023]
Abstract
Several lines of evidence suggest that dopamine modulates working memory (the ability to faithfully maintain and efficiently manipulate information over time) but its specific role has not been fully defined. Nor is it clear whether any effects of dopamine are specific to memory processes or whether they reflect more general cognitive mechanisms that extend beyond the working memory domain. Here, we examine the effect of haloperidol, principally a dopamine D2 receptor antagonist, on the ability of humans to ignore distracting information or update working memory contents. We compare these effects to performance on an independent measure of cognitive control (response conflict) which has minimal memory requirements. Haloperidol did not selectively affect the ability to ignore or update, but instead reduced the overall quality of recall. In addition, it impaired the ability to overcome response conflict. The deleterious effect of haloperidol on response conflict was selectively associated with the negative effect of the drug on ignoring - but not updating - suggesting that dopamine affects protection of working memory contents and inhibition in response conflict through a common mechanism. These findings provide new insights into the role of dopamine D2 receptors on human cognition. They suggest that D2 receptor effects on protecting the memory contents from distraction might be related to a more general process that supports inhibitory control in contexts that do not require working memory.
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Affiliation(s)
- Sean James Fallon
- Department of Experimental Psychology, University of Oxford, Oxford, UK.
| | - Kinan Muhammed
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Daniel S Drew
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK
| | - Yuen-Siang Ang
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Sanjay G Manohar
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK
| | - Masud Husain
- Department of Experimental Psychology, University of Oxford, Oxford, UK; Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK
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11
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Tribute to Glyn W. Humphreys, 1954-2016. Cortex 2018; 107:1-3. [PMID: 30119895 DOI: 10.1016/j.cortex.2018.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 07/04/2018] [Indexed: 11/23/2022]
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12
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Balaban H, Drew T, Luria R. Delineating resetting and updating in visual working memory based on the object-to-representation correspondence. Neuropsychologia 2018; 113:85-94. [PMID: 29605595 DOI: 10.1016/j.neuropsychologia.2018.03.038] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 03/13/2018] [Accepted: 03/28/2018] [Indexed: 11/15/2022]
Abstract
When an object we represent in visual working memory (VWM) changes, its representation is modified accordingly. VWM can either access and change the existing representation by an updating process, or it can reset, by encoding the object in its novel status as a new representation. Our goal was to show that the determining factor of updating versus resetting is the availability of a stable correspondence between the object and its VWM representation. Here, we demonstrate that updating relies on the object-to-representation mapping to access and modify the appropriate representation, while losing this mapping triggers a resetting process. We compared very similar situations of object separation that either allowed the mapping to hold, or caused it to be lost. When an object that was mapped to one representation separated, VWM reset, manifested by a sharp drop in the contralateral delay activity (CDA) amplitude (an electrophysiological marker of VWM contents; Experiment 1), and a behavioral cost to detect salient changes that co-occurred with the resetting-triggering event (Experiment 2). When each part was mapped to a different representation, the separation resulted in updating, with a gradual rise in CDA amplitude (Experiment 1), and a reduced behavioral cost (Experiment 2). Thus, while updating and resetting resulted in similar final representations (corresponding to the post-change objects), their dynamics were different, depending on the availability of the mapping. Our results reveal the triggering conditions of resetting and updating, establish methods to study these online processes, and highlight the importance of the object-to-representation correspondence in VWM.
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Affiliation(s)
- Halely Balaban
- Sagol School of Neuroscience and the School of Psychological Science, Tel Aviv University, Tel Aviv 6997801, Israel.
| | - Trafton Drew
- Psychology Department, University of Utah, Salt Lake City 84112, UT, United States
| | - Roy Luria
- Sagol School of Neuroscience and the School of Psychological Science, Tel Aviv University, Tel Aviv 6997801, Israel
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