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Leenaars CH, Van der Mierden S, Joosten RN, Van der Weide MA, Schirris M, Dematteis M, Meijboom FL, Feenstra MG, Bleich A. Risk-Based Decision Making: A Systematic Scoping Review of Animal Models and a Pilot Study on the Effects of Sleep Deprivation in Rats. Clocks Sleep 2021; 3:31-52. [PMID: 33498259 PMCID: PMC7838799 DOI: 10.3390/clockssleep3010003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/13/2021] [Accepted: 01/18/2021] [Indexed: 02/07/2023] Open
Abstract
Animals, including humans, frequently make decisions involving risk or uncertainty. Different strategies in these decisions can be advantageous depending the circumstances. Short sleep duration seems to be associated with more risky decisions in humans. Animal models for risk-based decision making can increase mechanistic understanding, but very little data is available concerning the effects of sleep. We combined primary- and meta-research to explore the relationship between sleep and risk-based decision making in animals. Our first objective was to create an overview of the available animal models for risky decision making. We performed a systematic scoping review. Our searches in Pubmed and Psychinfo retrieved 712 references, of which 235 were included. Animal models for risk-based decision making have been described for rodents, non-human primates, birds, pigs and honey-bees. We discuss task designs and model validity. Our second objective was to apply this knowledge and perform a pilot study on the effect of sleep deprivation. We trained and tested male Wistar rats on a probability discounting task; a “safe” lever always resulted in 1 reward, a “risky” lever resulted in 4 or no rewards. Rats adapted their preferences to variations in reward probabilities (p < 0.001), but 12 h of sleep deprivation during the light phase did not clearly alter risk preference (p = 0.21).
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Affiliation(s)
- Cathalijn H.C. Leenaars
- Institute for Laboratory Animal Science, Hannover Medical School, 30625 Hannover, Germany; (S.V.d.M.); (A.B.)
- Department for Health Evidence (Section HTA), SYRCLE, Radboud University Medical Centre, 6600 Nijmegen, The Netherlands
- Unit Animals in Science and Society, Population Health Sciences, Utrecht University, 3500 Utrecht, The Netherlands;
- Correspondence: ; Tel.: +49-511-532-1368
| | - Stevie Van der Mierden
- Institute for Laboratory Animal Science, Hannover Medical School, 30625 Hannover, Germany; (S.V.d.M.); (A.B.)
- Department for Health Evidence (Section HTA), SYRCLE, Radboud University Medical Centre, 6600 Nijmegen, The Netherlands
| | - Ruud N.J.M.A. Joosten
- Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, 1000 Amsterdam, The Netherlands; (R.N.J.M.A.J.); (M.A.V.d.W.); (M.S.); (M.G.P.F.)
| | - Marnix A. Van der Weide
- Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, 1000 Amsterdam, The Netherlands; (R.N.J.M.A.J.); (M.A.V.d.W.); (M.S.); (M.G.P.F.)
| | - Mischa Schirris
- Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, 1000 Amsterdam, The Netherlands; (R.N.J.M.A.J.); (M.A.V.d.W.); (M.S.); (M.G.P.F.)
| | - Maurice Dematteis
- Department of Addiction Medicine, Grenobles Alpes University Hospital, Faculty of Medicine, Grenoble Alpes University, 38400 Grenoble, France;
| | - Franck L.B. Meijboom
- Unit Animals in Science and Society, Population Health Sciences, Utrecht University, 3500 Utrecht, The Netherlands;
| | - Matthijs G.P. Feenstra
- Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, 1000 Amsterdam, The Netherlands; (R.N.J.M.A.J.); (M.A.V.d.W.); (M.S.); (M.G.P.F.)
| | - André Bleich
- Institute for Laboratory Animal Science, Hannover Medical School, 30625 Hannover, Germany; (S.V.d.M.); (A.B.)
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Exploring dopaminergic transmission in gambling addiction: A systematic translational review. Neurosci Biobehav Rev 2020; 119:481-511. [DOI: 10.1016/j.neubiorev.2020.09.034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 08/16/2020] [Accepted: 09/26/2020] [Indexed: 12/15/2022]
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Sescousse G, Janssen LK, Hashemi MM, Timmer MHM, Geurts DEM, ter Huurne NP, Clark L, Cools R. Amplified Striatal Responses to Near-Miss Outcomes in Pathological Gamblers. Neuropsychopharmacology 2016; 41:2614-23. [PMID: 27006113 PMCID: PMC4987843 DOI: 10.1038/npp.2016.43] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 02/17/2016] [Accepted: 03/18/2016] [Indexed: 01/06/2023]
Abstract
Near-misses in gambling games are losing events that come close to a win. Near-misses were previously shown to recruit reward-related brain regions including the ventral striatum, and to invigorate gambling behavior, supposedly by fostering an illusion of control. Given that pathological gamblers are particularly vulnerable to such cognitive illusions, their persistent gambling behavior might result from an amplified striatal sensitivity to near-misses. In addition, animal studies have shown that behavioral responses to near-miss-like events are sensitive to dopamine, but this dopaminergic influence has not been tested in humans. To investigate these hypotheses, we recruited 22 pathological gamblers and 22 healthy controls who played a slot machine task delivering wins, near-misses and full-misses, inside an fMRI scanner. Each participant played the task twice, once under placebo and once under a dopamine D2 receptor antagonist (sulpiride 400 mg), in a double-blind, counter-balanced design. Participants were asked about their motivation to continue gambling throughout the task. Across all participants, near-misses elicited higher motivation to continue gambling and increased striatal responses compared with full-misses. Crucially, pathological gamblers showed amplified striatal responses to near-misses compared with controls. These group differences were not observed following win outcomes. In contrast to our hypothesis, sulpiride did not induce any reliable modulation of brain responses to near-misses. Together, our results demonstrate that pathological gamblers have amplified brain responses to near-misses, which likely contribute to their persistent gambling behavior. However, there is no evidence that these responses are influenced by dopamine. These results have implications for treatment and gambling regulation.
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Affiliation(s)
- Guillaume Sescousse
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
- Department of Psychiatry, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Lieneke K Janssen
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
- Department of Psychiatry, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Mahur M Hashemi
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
| | - Monique H M Timmer
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
- Department of Neurology, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Dirk E M Geurts
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
- Department of Psychiatry, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Niels P ter Huurne
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
- Karakter Child and Adolescent Psychiatry University Centre, Nijmegen, The Netherlands
| | - Luke Clark
- Department of Psychology, Centre for Gambling Research at UBC, University of British Columbia, Vancouver, British Columbia, Canada
| | - Roshan Cools
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
- Department of Psychiatry, Radboud University Medical Centre, Nijmegen, The Netherlands
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Ricker JM, Hatch JD, Powers DD, Cromwell HC. Fractionating choice: A study on reward discrimination, preference, and relative valuation in the rat (Rattus norvegicus). ACTA ACUST UNITED AC 2016; 130:174-86. [PMID: 27078079 DOI: 10.1037/com0000034] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Choice behavior combines discrimination between distinctive outcomes, preference for specific outcomes and relative valuation of comparable outcomes. Previous work has focused on 1 component (i.e., preference) disregarding other influential processes that might provide a more complete understanding. Animal models of choice have been explored primarily utilizing extensive training, limited freedom for multiple decisions and sparse behavioral measures constrained to a single phase of motivated action. The present study used a paradigm that combines different elements of previous methods with the goal to distinguish among components of choice and explore how well components match predictions based on risk-sensitive foraging strategies. In order to analyze discrimination and relative valuation, it was necessary to have an option that shifted and an option that remained constant. Shifting outcomes among weeks included a change in single-option outcome (0 to 1 to 2 pellets) or a change in mixed-option outcome (0 or 5 to 0 or 3 to 0 or 1 pellets). Constant outcomes among weeks were also mixed-option (0 or 3 pellets) or single-option (1 pellet). Shifting single-option outcomes among weeks led to better discrimination, more robust preference and significant incentive contrast effects for the alternative outcome. Shifting multioptions altered choice components and led to dissociations among discrimination, preference, and reduced contrast effects. During extinction, all components were impacted with the greatest deficits during the shifting mixed-option outcome sessions. Results suggest choice behavior can be optimized for 1 component but suboptimal for others depending upon the complexity of alterations in outcome value between options. (PsycINFO Database Record
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Affiliation(s)
- Joshua M Ricker
- J.P. Scott Center for Neuroscience, Mind and Behavior, Bowling Green State University
| | - Justin D Hatch
- J.P. Scott Center for Neuroscience, Mind and Behavior, Bowling Green State University
| | - Daniel D Powers
- J.P. Scott Center for Neuroscience, Mind and Behavior, Bowling Green State University
| | - Howard Casey Cromwell
- J.P. Scott Center for Neuroscience, Mind and Behavior, Bowling Green State University
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Moreira PS, Sotiropoulos I, Silva J, Takashima A, Sousa N, Leite-Almeida H, Costa PS. The Advantages of Structural Equation Modeling to Address the Complexity of Spatial Reference Learning. Front Behav Neurosci 2016; 10:18. [PMID: 26955327 PMCID: PMC4767929 DOI: 10.3389/fnbeh.2016.00018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 02/01/2016] [Indexed: 11/28/2022] Open
Abstract
Background: Cognitive performance is a complex process influenced by multiple factors. Cognitive assessment in experimental animals is often based on longitudinal datasets analyzed using uni- and multi-variate analyses, that do not account for the temporal dimension of cognitive performance and also do not adequately quantify the relative contribution of individual factors onto the overall behavioral outcome. To circumvent these limitations, we applied an Autoregressive Latent Trajectory (ALT) to analyze the Morris water maze (MWM) test in a complex experimental design involving four factors: stress, age, sex, and genotype. Outcomes were compared with a traditional Mixed-Design Factorial ANOVA (MDF ANOVA). Results: In both the MDF ANOVA and ALT models, sex, and stress had a significant effect on learning throughout the 9 days. However, on the ALT approach, the effects of sex were restricted to the learning growth. Unlike the MDF ANOVA, the ALT model revealed the influence of single factors at each specific learning stage and quantified the cross interactions among them. In addition, ALT allows us to consider the influence of baseline performance, a critical and unsolved problem that frequently yields inaccurate interpretations in the classical ANOVA model. Discussion: Our findings suggest the beneficial use of ALT models in the analysis of complex longitudinal datasets offering a better biological interpretation of the interrelationship of the factors that may influence cognitive performance.
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Affiliation(s)
- Pedro S Moreira
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of MinhoBraga, Portugal; ICVS/3B's - PT Government Associate LaboratoryBraga/Guimarães, Portugal
| | - Ioannis Sotiropoulos
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of MinhoBraga, Portugal; ICVS/3B's - PT Government Associate LaboratoryBraga/Guimarães, Portugal
| | - Joana Silva
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of MinhoBraga, Portugal; ICVS/3B's - PT Government Associate LaboratoryBraga/Guimarães, Portugal
| | - Akihiko Takashima
- RIKEN Brain Science Institute, Laboratory for Alzheimers DiseaseSaitama, Japan; Department of Aging Neurobiology, National Center for Geriatrics and GerontologyOhbu, Japan
| | - Nuno Sousa
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of MinhoBraga, Portugal; ICVS/3B's - PT Government Associate LaboratoryBraga/Guimarães, Portugal
| | - Hugo Leite-Almeida
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of MinhoBraga, Portugal; ICVS/3B's - PT Government Associate LaboratoryBraga/Guimarães, Portugal
| | - Patrício S Costa
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of MinhoBraga, Portugal; ICVS/3B's - PT Government Associate LaboratoryBraga/Guimarães, Portugal
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Morgado P, Marques F, Ribeiro B, Leite-Almeida H, Pêgo JM, Rodrigues AJ, Dalla C, Kokras N, Sousa N, Cerqueira JJ. Stress induced risk-aversion is reverted by D2/D3 agonist in the rat. Eur Neuropsychopharmacol 2015; 25:1744-52. [PMID: 26233608 DOI: 10.1016/j.euroneuro.2015.07.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 06/16/2015] [Accepted: 07/14/2015] [Indexed: 01/14/2023]
Abstract
Stress exposure triggers cognitive and behavioral impairments that influence decision-making processes. Decisions under a context of uncertainty require complex reward-prediction processes that are known to be mediated by the mesocorticolimbic dopamine (DA) system in brain areas sensitive to the deleterious effects of chronic stress, in particular the orbitofrontal cortex (OFC). Using a decision-making task, we show that chronic stress biases risk-based decision-making to safer behaviors. This decision-making pattern is associated with an increased activation of the lateral part of the OFC and with morphological changes in pyramidal neurons specifically recruited by this task. Additionally, stress exposure induces a hypodopaminergic status accompanied by increased mRNA levels of the dopamine receptor type 2 (Drd2) in the OFC; importantly, treatment with a D2/D3 agonist quinpirole reverts the shift to safer behaviors induced by stress on risky decision-making. These results suggest that the brain mechanisms related to risk-based decision-making are altered after chronic stress, but can be modulated by manipulation of dopaminergic transmission.
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MESH Headings
- Animals
- Chronic Disease
- Decision Making/drug effects
- Decision Making/physiology
- Disease Models, Animal
- Dopamine/metabolism
- Dopamine Agonists/pharmacology
- Male
- Prefrontal Cortex/drug effects
- Prefrontal Cortex/metabolism
- Prefrontal Cortex/pathology
- Pyramidal Cells/drug effects
- Pyramidal Cells/metabolism
- Pyramidal Cells/pathology
- Quinpirole/pharmacology
- RNA, Messenger
- Rats, Wistar
- Receptors, Dopamine D2/agonists
- Receptors, Dopamine D2/metabolism
- Receptors, Dopamine D3/agonists
- Receptors, Dopamine D3/metabolism
- Risk-Taking
- Stress, Psychological/drug therapy
- Stress, Psychological/metabolism
- Stress, Psychological/pathology
- Uncertainty
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Affiliation(s)
- Pedro Morgado
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal.; ICVS-3Bs PT Government Associate Laboratory, Braga, Guimarães, Portugal
| | - Fernanda Marques
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal.; ICVS-3Bs PT Government Associate Laboratory, Braga, Guimarães, Portugal
| | - Beatriz Ribeiro
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal.; ICVS-3Bs PT Government Associate Laboratory, Braga, Guimarães, Portugal
| | - Hugo Leite-Almeida
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal.; ICVS-3Bs PT Government Associate Laboratory, Braga, Guimarães, Portugal
| | - José M Pêgo
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal.; ICVS-3Bs PT Government Associate Laboratory, Braga, Guimarães, Portugal
| | - Ana J Rodrigues
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal.; ICVS-3Bs PT Government Associate Laboratory, Braga, Guimarães, Portugal
| | - Christina Dalla
- Department of Pharmacology, Medical School, University of Athens, Athens, Greece
| | - Nikos Kokras
- Department of Pharmacology, Medical School, University of Athens, Athens, Greece; First Department of Psychiatry, Eginition Hospital, Medical School, University of Athens, Athens, Greece
| | - Nuno Sousa
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal.; ICVS-3Bs PT Government Associate Laboratory, Braga, Guimarães, Portugal
| | - João J Cerqueira
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal.; ICVS-3Bs PT Government Associate Laboratory, Braga, Guimarães, Portugal.
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Oswald LM, Wand GS, Wong DF, Brown CH, Kuwabara H, Brašić JR. Risky decision-making and ventral striatal dopamine responses to amphetamine: a positron emission tomography [(11)C]raclopride study in healthy adults. Neuroimage 2015; 113:26-36. [PMID: 25795343 PMCID: PMC4433778 DOI: 10.1016/j.neuroimage.2015.03.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 02/05/2015] [Accepted: 03/10/2015] [Indexed: 02/06/2023] Open
Abstract
Recent functional magnetic resonance imaging (fMRI) studies have provided compelling evidence that corticolimbic brain regions are integrally involved in human decision-making. Although much less is known about molecular mechanisms, there is growing evidence that the mesolimbic dopamine (DA) neurotransmitter system may be an important neural substrate. Thus far, direct examination of DA signaling in human risk-taking has centered on gambling disorder. Findings from several positron emission tomography (PET) studies suggest that dysfunctions in mesolimbic DA circuits may play an important role in gambling behavior. Nevertheless, interpretation of these findings is currently hampered by a need for better understanding of how individual differences in regional DA function influence normative decision-making in humans. To further our understanding of these processes, we used [(11)C]raclopride PET to examine associations between ventral striatal (VS) DA responses to amphetamine (AMPH) and risky decision-making in a sample of healthy young adults with no history of psychiatric disorder, Forty-five male and female subjects, ages 18-29 years, completed a computerized version of the Iowa Gambling Task. Participants then underwent two 90-minute PET studies with high specific activity [(11)C]raclopride. The first scan was preceded by intravenous saline; the second, by intravenous AMPH (0.3mg/kg). Findings of primary analyses showed that less advantageous decision-making was associated with greater right VS DA release; the relationship did not differ as a function of gender. No associations were observed between risk-taking and left VS DA release or baseline D2/D3 receptor availability in either hemisphere. Overall, the results support notions that variability in striatal DA function may mediate inter-individual differences in risky decision-making in healthy adults, further suggesting that hypersensitive DA circuits may represent a risk pathway in this population.
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Affiliation(s)
- Lynn M Oswald
- Department of Family and Community Health, University of Maryland School of Nursing, Baltimore, MD 21201, USA; Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| | - Gary S Wand
- Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Dean F Wong
- Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Environmental Health Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Clayton H Brown
- Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Hiroto Kuwabara
- The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - James R Brašić
- The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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Mai B, Sommer S, Hauber W. Dopamine D1/D2 Receptor Activity in the Nucleus Accumbens Core But Not in the Nucleus Accumbens Shell and Orbitofrontal Cortex Modulates Risk-Based Decision Making. Int J Neuropsychopharmacol 2015; 18:pyv043. [PMID: 25908669 PMCID: PMC4648164 DOI: 10.1093/ijnp/pyv043] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND It is well known that brain dopamine (DA) signals support risk-based decision making; however, the specific terminal regions of midbrain DA neurons through which DA signals mediate risk-based decision making are unknown. METHODS Using microinfusions of the D1/D2 receptor antagonist flupenthixol, we sought to explore the role of D1/D2 receptor activity in the rat orbitofrontal cortex (OFC) and core and shell regions of the nucleus accumbens (AcbC and AcbS, respectively) in the regulation of risky choices. A risk-discounting task was used that involves choices between a certain small-reward lever that always delivered 1 pellet or a risky large-reward lever which delivered 4 pellets but had a decreasing probability of receiving the reward across 4 subsequent within-session trial blocks (100%, 50%, 25%, 12.5%). To validate task sensitivity to experimental manipulations of DA activity, we also examined the effects of systemic amphetamine and flupenthixol. RESULTS Systemic amphetamine increased while systemic flupenthixol reduced risky choices. Results further demonstrate that rats that received intra-AcbC flupenthixol were able to track increasing risk associated with the risky lever but displayed a generally reduced preference for the risky lever across all trial blocks, including in the initial trial block (large reward at 100%). Microinfusions of flupenthixol into the AcbS or OFC did not alter risk-based decision making. CONCLUSIONS Our data suggest that intra-AcbC D1/D2 receptor signaling does not support the ability to track shifts in reward probabilities but does bias risk-based decision making. That is, it increased the rats' preference for the response option known to be associated with higher risk-related costs.
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Affiliation(s)
| | | | - Wolfgang Hauber
- Department Animal Physiology, University of Stuttgart, Stuttgart, Germany (Mrs Mai, Sommer, and Dr Hauber).
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