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Shen H, Ma Z, Hans E, Duan Y, Bi GH, Chae YC, Bonifazi A, Battiti FO, Newman AH, Xi ZX, Yang Y. Involvement of dopamine D3 receptor in impulsive choice decision-making in male rats. Neuropharmacology 2024; 257:110051. [PMID: 38917939 DOI: 10.1016/j.neuropharm.2024.110051] [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: 04/13/2024] [Revised: 06/20/2024] [Accepted: 06/21/2024] [Indexed: 06/27/2024]
Abstract
Impulsive decision-making has been linked to impulse control disorders and substance use disorders. However, the neural mechanisms underlying impulsive choice are not fully understood. While previous PET imaging and autoradiography studies have shown involvement of dopamine and D2/3 receptors in impulsive behavior, the roles of distinct D1, D2, and D3 receptors in impulsive decision-making remain unclear. In this study, we used a food reward delay-discounting task (DDT) to identify low- and high-impulsive rats, in which low-impulsive rats exhibited preference for large delayed reward over small immediate rewards, while high-impulsive rats showed the opposite preference. We then examined D1, D2, and D3 receptor gene expression using RNAscope in situ hybridization assays. We found that high-impulsive male rats exhibited lower levels of D2 and D3, and particularly D3, receptor expression in the nucleus accumbens (NAc), with no significant changes in the insular, prelimbic, and infralimbic cortices. Based on these findings, we further explored the role of the D3 receptor in impulsive decision-making. Systemic administration of a selective D3 receptor agonist (FOB02-04) significantly reduced impulsive choices in high-impulsive rats but had no effects in low-impulsive rats. Conversely, a selective D3 receptor antagonist (VK4-116) produced increased both impulsive and omission choices in both groups of rats. These findings suggest that impulsive decision-making is associated with a reduction in D3 receptor expression in the NAc. Selective D3 receptor agonists, but not antagonists, may hold therapeutic potentials for mitigating impulsivity in high-impulsive subjects.
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Affiliation(s)
- Hui Shen
- Neuroimaging Research Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, 21224, USA
| | - Zilu Ma
- Neuroimaging Research Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, 21224, USA
| | - Emma Hans
- Neuroimaging Research Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, 21224, USA
| | - Ying Duan
- Neuroimaging Research Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, 21224, USA
| | - Guo-Hua Bi
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, 21224, USA
| | - Yurim C Chae
- Neuroimaging Research Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, 21224, USA
| | - Alessandro Bonifazi
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, 21224, USA
| | - Francisco O Battiti
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, 21224, USA
| | - Amy Hauck Newman
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, 21224, USA
| | - Zheng-Xiong Xi
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, 21224, USA.
| | - Yihong Yang
- Neuroimaging Research Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, 21224, USA.
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Yates JR, Prior NA, Chitwood MR, Day HA, Heidel JR, Hopkins SE, Muncie BT, Paradella-Bradley TA, Sestito AP, Vecchiola AN, Wells EE. Effects of GluN2B-selective antagonists on delay and probability discounting in male rats: Modulation by delay/probability presentation order. Exp Clin Psychopharmacol 2018; 26:525-540. [PMID: 30035577 PMCID: PMC6283694 DOI: 10.1037/pha0000216] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The contribution of the GluN2B subunit of the NMDA receptor to impulsivity has recently been examined. Ro 63-1908, a highly selective antagonist for the GluN2B, decreases impulsive choice. Because the order in which delays are presented modulates drug effects in discounting procedures, one goal of the current study was to determine the effects of Ro 63-1908 in delay discounting procedures in which the delays to obtaining the large reinforcer either increase or decrease across the session. We also determined if Ro 63-1908 differentially alters risky choice in probability discounting procedures that use ascending/descending schedules. Male rats were trained in either delay (n = 24) or probability (n = 24) discounting in which the delay to/odds against reinforcement were presented in either ascending or descending order (n = 12 each schedule). Following training, rats received the GluN2B antagonists Ro 63-1908 (0-1.0 mg/kg) and CP-101,606 (0-3.0 mg/kg). In delay discounting, Ro 63-1908 (1.0 mg/kg), but not CP-101,606, decreased choice for the large reinforcer, but only when the delays decreased across the session. In probability discounting, Ro 63-1908 (0.3 mg/kg)/CP-101,606 (1.0 mg/kg) increased choice for the large reinforcer when the probability of obtaining this alternative decreased across the session, but Ro 63-1908 (1.0 mg/kg)/CP-101,606 (3.0 mg/kg) decreased choice when the probabilities increased. These results show that the GluN2B is a mediator of impulsive/risky choice, but the effects of GluN2B antagonists are dependent on the order in which delays/probabilities are presented. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
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Mori M, Tsutsui-Kimura I, Mimura M, Tanaka KF. 5-HT 3 antagonists decrease discounting rate without affecting sensitivity to reward magnitude in the delay discounting task in mice. Psychopharmacology (Berl) 2018; 235:2619-2629. [PMID: 29955899 DOI: 10.1007/s00213-018-4954-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 06/19/2018] [Indexed: 01/15/2023]
Abstract
RATIONALE Impulsive choice has often been evaluated in rodents according to the proportion of choices for the delayed large magnitude reinforcer (%large choice) in a delay-discounting task (DDT). However, because %large choice is influenced by both sensitivity to reinforcer magnitude and sensitivity to delayed reinforcement (i.e., discounting rate), distinctively evaluating such discounting parameters represents a critical issue demanding methods to determine each parameter in rats. The serotonin (5-HT) system is well known to be involved in impulsive choice; nevertheless, only a few studies have distinguished discounting parameters and investigated how 5-HT modulators affect discounting rate. OBJECTIVE Here, we performed a discounting parameter analysis in mice and examined the effects of various 5-HT modulators on discounting rate. METHODS We set up DDTs with different delay schedules to determine which schedule could address delay-discounting rates in mice. We examined the effect of the following drugs on impulsive choice: a 5-HT reuptake inhibitor (paroxetine), a 5-HT1A receptor agonist (8-OH-DPAT), and two 5-HT3 receptor antagonists (granisetron and ondansetron). RESULTS Mice showed typical delay discounting at the shorter delay schedules (up to 4 s delay). The %large choice under shorter, but not longer, schedules followed an exponential function and allowed us to derive discounting rates. We selected a DDT with a 4-s delay schedule for further experiments. Granisetron and ondansetron, but not paroxetine or 8-OH-DPAT, decreased discounting rates without affecting sensitivity to reinforcer magnitude. CONCLUSION We found that a method to calculate discounting rates in rats is also applicable to mouse models. We also provided evidence that 5-HT3 antagonism controls impulsive choice in mice.
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Affiliation(s)
- Marina Mori
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, 160-8582, Japan
| | - Iku Tsutsui-Kimura
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, 160-8582, Japan. .,Center for Brain Science, Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, 02138, USA. .,JSPS Overseas Research Fellow, Tokyo, 102-0083, Japan.
| | - Masaru Mimura
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, 160-8582, Japan
| | - Kenji F Tanaka
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, 160-8582, Japan.
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Yates JR. Dissecting drug effects in preclinical models of impulsive choice: emphasis on glutamatergic compounds. Psychopharmacology (Berl) 2018; 235:607-626. [PMID: 29305628 PMCID: PMC5823766 DOI: 10.1007/s00213-017-4825-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 12/27/2017] [Indexed: 01/10/2023]
Abstract
RATIONALE Impulsive choice is often measured with delay discounting paradigms. Because there are multiple discounting procedures, as well as different statistical analyses that can be applied to data generated from these paradigms, there are some inconsistencies in the literature regarding drug effects on impulsive choice. OBJECTIVES The goal of the current paper is to review the methodological and analytic approaches used to measure discounting and to discuss how these differences can account for differential drug effects observed across studies. RESULTS Because some procedures/analyses use a single data point as the dependent variable, changes in this value following pharmacological treatment may be interpreted as alterations in sensitivity to delayed reinforcement, but when other procedures/analyses are used, no changes in behavior are observed. Even when multiple data points are included, some studies show that the statistical analysis (e.g., ANOVA on raw proportion of responses vs. using hyperbolic/exponential functions) can lead to different interpretations. Finally, procedural differences (e.g., delay presentation order, signaling the delay to reinforcement, etc.) in the same discounting paradigm can alter how drugs affect sensitivity to delayed reinforcement. CONCLUSIONS Future studies should utilize paradigms that allow one to observe alterations in responding at each delay (e.g., concurrent-chains schedules). Concerning statistical analyses, using parameter estimates derived from nonlinear functions or incorporating the generalized matching law can allow one to determine if drugs affect sensitivity to delayed reinforcement or impair discrimination of the large and small magnitude reinforcers. Using these approaches can help further our understanding of the neurochemical underpinnings of delay discounting.
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Affiliation(s)
- Justin R Yates
- Department of Psychological Science, Northern Kentucky University, 1 Nunn Drive, Highland Heights, KY, 41099, USA.
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Nautiyal KM, Wall MM, Wang S, Magalong VM, Ahmari SE, Balsam PD, Blanco C, Hen R. Genetic and Modeling Approaches Reveal Distinct Components of Impulsive Behavior. Neuropsychopharmacology 2017; 42:1182-1191. [PMID: 27976680 PMCID: PMC5437890 DOI: 10.1038/npp.2016.277] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 11/24/2016] [Accepted: 12/02/2016] [Indexed: 02/07/2023]
Abstract
Impulsivity is an endophenotype found in many psychiatric disorders including substance use disorders, pathological gambling, and attention deficit hyperactivity disorder. Two behavioral features often considered in impulsive behavior are behavioral inhibition (impulsive action) and delayed gratification (impulsive choice). However, the extent to which these behavioral constructs represent distinct facets of behavior with discrete biological bases is unclear. To test the hypothesis that impulsive action and impulsive choice represent statistically independent behavioral constructs in mice, we collected behavioral measures of impulsivity in a single cohort of mice using well-validated operant behavioral paradigms. Mice with manipulation of serotonin 1B receptor (5-HT1BR) expression were included as a model of disordered impulsivity. A factor analysis was used to characterize correlations between the measures of impulsivity and to identify covariates. Using two approaches, we dissociated impulsive action from impulsive choice. First, the absence of 5-HT1BRs caused increased impulsive action, but not impulsive choice. Second, based on an exploratory factor analysis, a two-factor model described the data well, with measures of impulsive action and choice separating into two independent factors. A multiple-indicator multiple-causes analysis showed that 5-HT1BR expression and sex were significant covariates of impulsivity. Males displayed increased impulsivity in both dimensions, whereas 5-HT1BR expression was a predictor of increased impulsive action only. These data support the conclusion that impulsive action and impulsive choice are distinct behavioral phenotypes with dissociable biological influences that can be modeled in mice. Our work may help inform better classification, diagnosis, and treatment of psychiatric disorders, which present with disordered impulsivity.
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Affiliation(s)
- Katherine M Nautiyal
- Department of Psychiatry, Columbia University, New York, NY, USA,Department of Psychiatry, New York State Psychiatric Institute, New York, NY, USA
| | - Melanie M Wall
- Department of Psychiatry, Columbia University, New York, NY, USA,Department of Psychiatry, New York State Psychiatric Institute, New York, NY, USA,Department of Biostatistics, Mailman School of Public Health, Columbia University, New York, NY, USA
| | - Shuai Wang
- Department of Psychiatry, New York State Psychiatric Institute, New York, NY, USA
| | - Valerie M Magalong
- Department of Psychiatry, New York State Psychiatric Institute, New York, NY, USA
| | - Susanne E Ahmari
- Department of Psychiatry, Translational Neuroscience Program; Center for Neuroscience Program and Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA, USA
| | - Peter D Balsam
- Department of Psychiatry, New York State Psychiatric Institute, New York, NY, USA,Psychology Departments, Barnard College and Columbia University, New York, NY, USA
| | - Carlos Blanco
- Department of Psychiatry, New York State Psychiatric Institute, New York, NY, USA,Center for Neurobiology and Behavior, Columbia University, 722 W. 168th St., P.I. Annex 731, 1051 Riverside Drive, Unit 87, New York, NY 10032, USA, Tel: 212 646 774 7104, Fax: 212 646 774 7102, E-mail: or
| | - René Hen
- Department of Psychiatry, Columbia University, New York, NY, USA,Department of Psychiatry, New York State Psychiatric Institute, New York, NY, USA,Department of Pharmacology, Columbia University, New York, NY, USA,Center for Neurobiology and Behavior, Columbia University, 722 W. 168th St., P.I. Annex 731, 1051 Riverside Drive, Unit 87, New York, NY 10032, USA, Tel: 212 646 774 7104, Fax: 212 646 774 7102, E-mail: or
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Yates JR, Gunkel BT, Rogers KK, Hughes MN, Prior NA. Effects of N-methyl-D-aspartate receptor ligands on sensitivity to reinforcer magnitude and delayed reinforcement in a delay-discounting procedure. Psychopharmacology (Berl) 2017; 234:461-473. [PMID: 27837332 PMCID: PMC5226882 DOI: 10.1007/s00213-016-4469-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 11/02/2016] [Indexed: 11/26/2022]
Abstract
RATIONALE The N-methyl-D-aspartate (NMDA) receptor has been recently identified as an important mediator of impulsive choice, as assessed in delay discounting. Although discounting is independently influenced by sensitivity to reinforcer magnitude and delayed reinforcement, few studies have examined how NMDA receptor ligands differentially affect these parameters. OBJECTIVES The current study examined the effects of various NMDA receptor ligands on sensitivity to reinforcer magnitude and delayed reinforcement in a delay-discounting procedure. METHODS Following behavioral training, rats received treatments of the following NMDA receptor ligands: the uncompetitive antagonists ketamine (0, 1.0, 5.0, or 10.0 mg/kg; i.p.), MK-801 (0, 0.003, 0.01, or 0.03 mg/kg; s.c.), and memantine (0, 2.5, 5.0, or 10.0 mg/kg; i.p.), the competitive antagonist CGS 19755 (0, 5.0, 10.0, or 20.0 mg/kg; s.c.), the non-competitive NR2B subunit-selective antagonist ifenprodil (0, 1.0, 3.0, or 10.0 mg/kg; i.p), and the partial agonist D-cycloserine (0, 3.25, 15.0, or 30.0 mg/kg; s.c.). RESULTS When an exponential model was used to describe discounting, CGS 19755 (5.0 mg/kg) increased impulsive choice without altering sensitivity to reinforcer magnitude. Conversely, ketamine (10.0 mg/kg), memantine (5.0 mg/kg), and ifenprodil (10.0 mg/kg) decreased sensitivity to reinforcer magnitude without altering impulsive choice. MK-801 and D-cycloserine did not alter delay-discounting performance, although two-way ANOVA analyses indicated D-cycloserine (15.0 mg/kg) decreased impulsive choice. CONCLUSIONS The behavioral changes observed in delay discounting following administration of NMDA receptor antagonists do not always reflect an alteration in impulsive choice. These results emphasize the utility in employing quantitative methods to assess drug effects in delay discounting.
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Affiliation(s)
- Justin R Yates
- Department of Psychological Science, Northern Kentucky University, 1 Nunn Drive, Highland Heights, KY, 41099, USA.
| | - Benjamin T Gunkel
- Department of Psychological Science, Northern Kentucky University, 1 Nunn Drive, Highland Heights, KY, 41099, USA
| | - Katherine K Rogers
- Department of Psychological Science, Northern Kentucky University, 1 Nunn Drive, Highland Heights, KY, 41099, USA
| | - Mallory N Hughes
- Department of Psychological Science, Northern Kentucky University, 1 Nunn Drive, Highland Heights, KY, 41099, USA
| | - Nicholas A Prior
- Department of Psychological Science, Northern Kentucky University, 1 Nunn Drive, Highland Heights, KY, 41099, USA
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Korte SM, Prins J, Van den Bergh FS, Oosting RS, Dupree R, Korte-Bouws GA, Westphal KG, Olivier B, Denys DA, Garland A, Güntürkün O. The 5-HT1A/1B-receptor agonist eltoprazine increases both catecholamine release in the prefrontal cortex and dopamine release in the nucleus accumbens and decreases motivation for reward and “waiting” impulsivity, but increases “stopping” impulsivity. Eur J Pharmacol 2017; 794:257-269. [DOI: 10.1016/j.ejphar.2016.11.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 11/03/2016] [Accepted: 11/16/2016] [Indexed: 10/20/2022]
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Tian L, Qin X, Sun J, Li X, Wei L. Differential effects of co-administration of oxotremorine with SCH 23390 on impulsive choice in high-impulsive rats and low-impulsive rats. Pharmacol Biochem Behav 2016; 142:56-63. [PMID: 26772787 DOI: 10.1016/j.pbb.2016.01.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 12/23/2015] [Accepted: 01/04/2016] [Indexed: 10/22/2022]
Abstract
The effect of acetylcholine on impulsive choice is thought to be due to interactions between cholinergic and dopaminergic systems, but this hypothesis has not been proven. This study investigated whether D1-like receptors were involved in the effects of the muscarinic cholinergic agonist oxotremorine on impulsive choice in high-impulsive rats (HI rats, n=8) and low-impulsive rats (LI rats, n=8) characterized by basal levels of impulsive choice in a delay-discounting task. The results revealed that oxotremorine (0.05mg/kg) significantly increased the choice of the large reinforcer in HI rats, whereas decreased the choice of the large reinforcer in LI rats. The D1-like antagonist SCH 23390 produced significant reductions in the large-reinforcer choice in HI rats (0.01mg/kg) and LI rats (0.005, 0.0075, and 0.01mg/kg). SCH 23390 significantly inhibited the increase in the choice of the large reinforcer induced by oxotremorine (0.05mg/kg) in HI rats at doses of 0.005 and 0.0075mg/kg, but enhanced the effect of oxotremorine in LI rats only at the dose of 0.0075mg/kg. These findings suggested that D1-like receptors might be involved in the differential effects of oxotremorine on impulsive choice between HI rats and LI rats.
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Affiliation(s)
- Lin Tian
- Beijing Key Laboratory of Learning and Cognition, Department of Psychology, Capital Normal University, Beijing 100048, China
| | - Xingna Qin
- Beijing Key Laboratory of Learning and Cognition, Department of Psychology, Capital Normal University, Beijing 100048, China
| | - Jinling Sun
- Beijing Key Laboratory of Learning and Cognition, Department of Psychology, Capital Normal University, Beijing 100048, China
| | - Xinwang Li
- Beijing Key Laboratory of Learning and Cognition, Department of Psychology, Capital Normal University, Beijing 100048, China.
| | - Li Wei
- Department of Endocrinology and Metabolism, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai 200233, China.
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Jupp B, Dalley JW. Convergent pharmacological mechanisms in impulsivity and addiction: insights from rodent models. Br J Pharmacol 2014; 171:4729-66. [PMID: 24866553 PMCID: PMC4209940 DOI: 10.1111/bph.12787] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 05/02/2014] [Accepted: 05/12/2014] [Indexed: 01/15/2023] Open
Abstract
Research over the last two decades has widely demonstrated that impulsivity, in its various forms, is antecedent to the development of drug addiction and an important behavioural trait underlying the inability of addicts to refrain from continued drug use. Impulsivity describes a variety of rapidly and prematurely expressed behaviours that span several domains from impaired response inhibition to an intolerance of delayed rewards, and is a core symptom of attention deficit hyperactivity disorder (ADHD) and other brain disorders. Various theories have been advanced to explain how impulsivity interacts with addiction both causally and as a consequence of chronic drug abuse; these acknowledge the strong overlaps in neural circuitry and mechanisms between impulsivity and addiction and the seemingly paradoxical treatment of ADHD with stimulant drugs with high abuse potential. Recent years have witnessed unprecedented progress in the elucidation of pharmacological mechanisms underpinning impulsivity. Collectively, this work has significantly improved the prospect for new therapies in ADHD as well as our understanding of the neural mechanisms underlying the shift from recreational drug use to addiction. In this review, we consider the extent to which pharmacological interventions that target impulsive behaviour are also effective in animal models of addiction. We highlight several promising examples of convergence based on empirical findings in rodent-based studies.
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Affiliation(s)
- B Jupp
- Behavioural and Clinical Neuroscience Institute and Department of Psychology, University of CambridgeCambridge, UK
- Florey Institute of Neuroscience and Mental Health, University of MelbourneParkville, Australia
| | - J W Dalley
- Behavioural and Clinical Neuroscience Institute and Department of Psychology, University of CambridgeCambridge, UK
- Department of Psychiatry, University of CambridgeCambridge, UK
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Abstract
Impulsivity is associated with various psychopathologies, and elevated impulsivity is typically disadvantageous. This manuscript reviews recent investigations into the neurobiology of impulsivity using human imaging techniques and animal models. Both human imaging and preclinical pharmacological manipulations have yielded important insights into the neurobiological underpinnings of impulsivity. A more thorough understanding of the complex neurobiology underlying aspects of impulsivity may provide insight into new treatment options that target elevated impulsivity and psychopathologies such as addictions.
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Affiliation(s)
- Marci R Mitchell
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT
| | - Marc N Potenza
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT ; Department of Neurobiology, Yale University School of Medicine, New Haven, CT ; Child Study Center, Yale University School of Medicine, New Haven, CT
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Eubig PA, Noe TE, Floresco SB, Sable JJ, Schantz SL. Sex differences in response to amphetamine in adult Long-Evans rats performing a delay-discounting task. Pharmacol Biochem Behav 2014; 118:1-9. [PMID: 24388843 PMCID: PMC3934103 DOI: 10.1016/j.pbb.2013.12.021] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2013] [Revised: 11/11/2013] [Accepted: 12/24/2013] [Indexed: 01/27/2023]
Abstract
The use of animal models to investigate experimental questions about impulsive behavior can provide valuable insight into problems that affect human health. The delay-discounting paradigm involves subjects choosing between smaller reinforcers delivered immediately and larger reinforcers that are delivered after a delay. This is an important experimental paradigm for examining impulsive choice in both laboratory species and humans. However, a shortcoming of previously published delay-discounting studies in animals is that typically only males were studied, reducing the applicability of these studies to human populations. In the present study, both female and male adult Long-Evans rats were trained to perform a delay-discounting task, with delays of 0, 5, 10, 20 and 40 s before delivery of the larger reinforcer. Because dopaminergic signaling is important in mediating this task, the effects of d-amphetamine and the dopamine receptor antagonist, cis-flupenthixol, on task performance were then examined. The main experimental measure was percent larger-reinforcer choice, which was defined as the percentage of experimental trials at each delay in which the delayed, larger reinforcer was chosen. There was no sex difference in percent larger-reinforcer choice during baseline performance of the task. However, d-amphetamine administration disrupted choice in females, as evidenced by <80% larger-reinforcer choice in half of the females, but none of the males, at 0.5 mg/kg. D-Amphetamine also differentially altered the latency to choose between immediate versus delayed reinforcers in females compared to males. In contrast, cis-flupenthixol did not have a sex-related effect on percent larger-reinforcer choice. These findings parallel the sex differences in response to amphetamine seen in human delay-discounting studies and underscore the importance of evaluating sex-based differences in baseline performance and in response to pharmacologic agents when utilizing animal models.
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Affiliation(s)
- Paul A Eubig
- Department of Comparative Biosciences, University of Illinois, Urbana, IL 61802, USA.
| | - Terese E Noe
- Department of Comparative Biosciences, University of Illinois, Urbana, IL 61802, USA
| | - Stan B Floresco
- Department of Psychology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Jeffrey J Sable
- Department of Behavioral Sciences, Christian Brothers University, Memphis, TN 38104, USA
| | - Susan L Schantz
- Department of Comparative Biosciences, University of Illinois, Urbana, IL 61802, USA; Neuroscience Program, University of Illinois, Urbana, IL 61802, USA
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Tanno T, Maguire DR, Henson C, France CP. Effects of amphetamine and methylphenidate on delay discounting in rats: interactions with order of delay presentation. Psychopharmacology (Berl) 2014; 231:85-95. [PMID: 23963529 PMCID: PMC3877712 DOI: 10.1007/s00213-013-3209-3] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Accepted: 07/06/2013] [Indexed: 01/27/2023]
Abstract
RATIONALE Drug effects on delay discounting are thought to reflect changes in sensitivity to reinforcer delay, although other behavioral mechanisms might be involved. One strategy for revealing the influence of different behavioral mechanisms is to alter features of the procedures in which they are studied. OBJECTIVE This experiment examined whether the order of delay presentation under within-session delay discounting procedures impacts drug effects on discounting. METHODS Rats responded under a discrete-trial choice procedure in which responses on one lever delivered one food pellet immediately and responses on the other lever delivered three food pellets either immediately or after a delay. The delay to the larger reinforcer (0, 4, 8, 16, and 32 s) was varied within session and the order of delay presentation (ascending or descending) varied between groups. RESULTS Amphetamine (0.1-1.78 mg/kg) and methylphenidate (1.0-17.8 mg/kg) shifted delay functions upward in the ascending group (increasing choice of the larger reinforcer) and downward in the descending group (decreasing choice of the larger reinforcer). Morphine (1.0-10.0 mg/kg) and delta-9-tetrahydrocannabinol (0.32-5.6 mg/kg) tended to shift the delay functions downward, regardless of order of delay presentation, thereby reducing choice of the larger reinforcer, even when both reinforcers were delivered immediately. CONCLUSION The effects of amphetamine and methylphenidate under delay discounting procedures differed depending on the order of delay presentation, indicating that drug-induced changes in discounting were due, in part, to mechanisms other than altered sensitivity to reinforcer delay. Instead, amphetamine and methylphenidate altered responding in a manner consistent with increased behavioral perseveration.
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Affiliation(s)
- Takayuki Tanno
- Departments of Pharmacology (TT, DRM, CH, CPF) and Psychiatry (CPF), University of Texas Health Science Center, San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, USA
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Jupp B, Caprioli D, Dalley JW. Highly impulsive rats: modelling an endophenotype to determine the neurobiological, genetic and environmental mechanisms of addiction. Dis Model Mech 2013; 6:302-11. [PMID: 23355644 PMCID: PMC3597013 DOI: 10.1242/dmm.010934] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Impulsivity describes the tendency of an individual to act prematurely without foresight and is associated with a number of neuropsychiatric co-morbidities, including drug addiction. As such, there is increasing interest in the neurobiological mechanisms of impulsivity, as well as the genetic and environmental influences that govern the expression of this behaviour. Tests used on rodent models of impulsivity share strong parallels with tasks used to assess this trait in humans, and studies in both suggest a crucial role of monoaminergic corticostriatal systems in the expression of this behavioural trait. Furthermore, rodent models have enabled investigation of the causal relationship between drug abuse and impulsivity. Here, we review the use of rodent models of impulsivity for investigating the mechanisms involved in this trait, and how these mechanisms could contribute to the pathogenesis of addiction.
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Affiliation(s)
- Bianca Jupp
- Behavioural and Cognitive Neurosciences Institute and The Department of Psychology, University of Cambridge, Downing Street, Cambridge, CB2 3EB, UK
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Winstanley CA. The utility of rat models of impulsivity in developing pharmacotherapies for impulse control disorders. Br J Pharmacol 2012; 164:1301-21. [PMID: 21410459 DOI: 10.1111/j.1476-5381.2011.01323.x] [Citation(s) in RCA: 166] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
High levels of impulsive behaviours are a clinically significant symptom in a range of psychiatric disorders, such as attention deficit hyperactivity disorder, bipolar disorder, personality disorders, pathological gambling and substance abuse. Although often measured using questionnaire assessments, levels of different types of impulsivity can also be determined using behavioural tests. Rodent analogues of these paradigms have been developed, and similar neural circuitry has been implicated in their performance in both humans and rats. In the current review, the methodology underlying the measurement of different aspects of impulsive action and choice are considered from the viewpoint of drug development, with a focus on the continuous performance task (CPT), stop-signal task (SST), go/no-go and delay-discounting paradigms. Current issues impeding translation between animal and human studies are identified, and comparisons drawn between the acute effects of dopaminergic, noradrenergic and serotonergic compounds across species. Although the field could benefit from a more systematic determination of different pharmacological agents across paradigms, there are signs of strong concordance between the animal and human data. However, the type of impulsivity measured appears to play a significant role, with the SST and delay discounting providing more consistent effects for dopaminergic drugs, while the CPT and SST show better predictive validity so far for serotonergic and noradrenergic compounds. Based on the available data, it would appear that these impulsivity models could be used more widely to identify potential pharmacotherapies for impulse control disorders. Novel targets within the glutamatergic and serotonergic system are also suggested.
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Homberg JR. Serotonin and decision making processes. Neurosci Biobehav Rev 2012; 36:218-36. [DOI: 10.1016/j.neubiorev.2011.06.001] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2011] [Revised: 05/27/2011] [Accepted: 06/02/2011] [Indexed: 10/18/2022]
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FREITAS DA ROCHA ARMANDO, BURATTINI MARCELONASCIMENTO, ROCHA FÁBIOTHEOTO, MASSAD EDUARDO. A NEUROECONOMIC MODELING OF ATTENTION-DEFICIT/HYPERACTIVITY DISORDER (ADHD). J BIOL SYST 2011. [DOI: 10.1142/s021833900900306x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In this paper we present a new neuroeconomics model for decision-making applied to the Attention-Deficit/Hyperactivity Disorder (ADHD). The model is based on the hypothesis that decision-making is dependent on the evaluation of expected rewards and risks assessed simultaneously in two decision spaces: the personal (PDS) and the interpersonal emotional spaces (IDS). Motivation to act is triggered by necessities identified in PDS or IDS. The adequacy of an action in fulfilling a given necessity is assumed to be dependent on the expected reward and risk evaluated in the decision spaces. Conflict generated by expected reward and risk influences the easiness (cognitive effort) and the future perspective of the decision-making. Finally, the willingness (not) to act is proposed to be a function of the expected reward (or risk), adequacy, easiness and future perspective. The two most frequent clinical forms are ADHD hyperactive(AD/HDhyp) and ADHD inattentive(AD/HDdin). AD/HDhyp behavior is hypothesized to be a consequence of experiencing high rewarding expectancies for short periods of time, low risk evaluation, and short future perspective for decision-making. AD/HDin is hypothesized to be a consequence of experiencing high rewarding expectancies for long periods of time, low risk evaluation, and long future perspective for decision-making.
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Affiliation(s)
| | | | - FÁBIO THEOTO ROCHA
- School of Medicine, University of São Paulo, Rua Teodoro Sampaio 115, CEP 05405-000, SP, Brazil
| | - EDUARDO MASSAD
- School of Medicine, University of São Paulo, Rua Teodoro Sampaio 115, CEP 05405-000, SP, Brazil
- London School of Hygiene and Tropical Medicine, UK
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Abstract
Impulsivity is widely regarded as a multidimensional trait that encompasses two or more distinct patterns of behavior, and dopaminergic systems are implicated in the expression of impulsive behavior in both humans and animal subjects. Impulsive choice, or the tendency to choose rewards associated with relatively little or no delay, has been extensively studied in humans and animal subjects using delay-discounting tasks. Here, delay-discounting procedures were used to assess the effects of receptor-selective dopaminergic agonists, antagonists, and dopamine transporter ligands on choices of immediate versus delayed sucrose pellets. The effects of d-amphetamine, GBR 12909, apomorphine, SKF 81297, sumanirole, pramipexole, ABT-724, SCH 23390, L-741,626, PG01037, and L-745,870 were assessed in 24 Sprague-Dawley rats. The only drugs to affect impulsive choice selectively without altering undelayed choice were the D1-like antagonist, SCH 23390 (0.01 mg/kg), and the D4 partial agonist, ABT-724 (3.2 mg/kg), which both increased impulsive choice. The shared effects of these compounds may be explained by their localization within the prefrontal cortex on different groups of neurons. None of the selective agonists and antagonists tested reduced impulsive choice, so further research is needed to determine if direct dopaminergic agonists or antagonists may be therapeutically useful in the treatment of impulse-control disorders.
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The Interaction of Haloperidol and Imipramine on Cost-benefit Decision Making in Rats. ACTA PSYCHOLOGICA SINICA 2010. [DOI: 10.3724/sp.j.1041.2010.00946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Perry JL, Joseph JE, Jiang Y, Zimmerman RS, Kelly TH, Darna M, Huettl P, Dwoskin LP, Bardo MT. Prefrontal cortex and drug abuse vulnerability: translation to prevention and treatment interventions. ACTA ACUST UNITED AC 2010; 65:124-49. [PMID: 20837060 DOI: 10.1016/j.brainresrev.2010.09.001] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Revised: 08/19/2010] [Accepted: 09/02/2010] [Indexed: 01/25/2023]
Abstract
Vulnerability to drug abuse is related to both reward seeking and impulsivity, two constructs thought to have a biological basis in the prefrontal cortex (PFC). This review addresses similarities and differences in neuroanatomy, neurochemistry and behavior associated with PFC function in rodents and humans. Emphasis is placed on monoamine and amino acid neurotransmitter systems located in anatomically distinct subregions: medial prefrontal cortex (mPFC); lateral prefrontal cortex (lPFC); anterior cingulate cortex (ACC); and orbitofrontal cortex (OFC). While there are complex interconnections and overlapping functions among these regions, each is thought to be involved in various functions related to health-related risk behaviors and drug abuse vulnerability. Among the various functions implicated, evidence suggests that mPFC is involved in reward processing, attention and drug reinstatement; lPFC is involved in decision-making, behavioral inhibition and attentional gating; ACC is involved in attention, emotional processing and self-monitoring; and OFC is involved in behavioral inhibition, signaling of expected outcomes and reward/punishment sensitivity. Individual differences (e.g., age and sex) influence functioning of these regions, which, in turn, impacts drug abuse vulnerability. Implications for the development of drug abuse prevention and treatment strategies aimed at engaging PFC inhibitory processes that may reduce risk-related behaviors are discussed, including the design of effective public service announcements, cognitive exercises, physical activity, direct current stimulation, feedback control training and pharmacotherapies. A major challenge in drug abuse prevention and treatment rests with improving intervention strategies aimed at strengthening PFC inhibitory systems among at-risk individuals.
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Affiliation(s)
- Jennifer L Perry
- Center for Drug Abuse Research Translation, University of Kentucky, Lexington, KY 40536-0509, USA
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Sonuga-Barke E, Bitsakou P, Thompson M. Beyond the dual pathway model: evidence for the dissociation of timing, inhibitory, and delay-related impairments in attention-deficit/hyperactivity disorder. J Am Acad Child Adolesc Psychiatry 2010; 49:345-55. [PMID: 20410727 DOI: 10.1016/j.jaac.2009.12.018] [Citation(s) in RCA: 158] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE The dual pathway model explains neuro-psychological heterogeneity in Attention Deficit/Hyperactivity Disorder (ADHD) in terms of dissociable cognitive and motivational deficits each affecting some but not other patients. We explore whether deficits in temporal processing might constitute a third dissociable neuropsychological component of ADHD. METHOD Nine tasks designed to tap three domains (inhibitory control, delay aversion and temporal processing) were administered to ADHD probands (n=71; ages 6 to 17 years), their siblings (n=71; 65 unaffected by ADHD) and a group of non-ADHD controls (n=50). IQ and working memory were measured. RESULTS Temporal processing, inhibitory control and delay-related deficits represented independent neuropsychological components. ADHD children differed from controls on all factors. For ADHD patients, the co-occurrence of inhibitory, temporal processing and delay-related deficits was no greater than expected by chance with substantial groups of patients showing only one problem. Domain-specific patterns of familial co-segregation provided evidence for the validity of neuropsychological subgroupings. CONCLUSION The current results illustrate the neuropsychological heterogeneity in ADHD and initial support for a triple pathway model. The findings need to be replicated in larger samples.
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Affiliation(s)
- Edmund Sonuga-Barke
- Institute for Disorder of Impulse and Attention, School of Psychology, University of Southampton, Highfield, Southampton SO17 1BJ, UK.
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Voon V, Reynolds B, Brezing C, Gallea C, Skaljic M, Ekanayake V, Fernandez H, Potenza MN, Dolan RJ, Hallett M. Impulsive choice and response in dopamine agonist-related impulse control behaviors. Psychopharmacology (Berl) 2010; 207:645-59. [PMID: 19838863 PMCID: PMC3676926 DOI: 10.1007/s00213-009-1697-y] [Citation(s) in RCA: 159] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Accepted: 10/02/2009] [Indexed: 01/25/2023]
Abstract
RATIONALE Dopaminergic medication-related impulse control disorders (ICDs) such as pathological gambling and compulsive shopping have been reported in Parkinson's disease (PD). HYPOTHESIS We hypothesized that dopamine agonists (DAs) would be associated with greater impulsive choice or greater discounting of delayed rewards in PD patients with ICDs (PDI). METHODS Fourteen PDI patients, 14 PD controls without ICDs, and 16 medication-free matched normal controls were tested on the Experiential Discounting Task (EDT), a feedback-based intertemporal choice task, spatial working memory, and attentional set shifting. The EDT was used to assess choice impulsivity (hyperbolic K value), reaction time (RT), and decision conflict RT (the RT difference between high conflict and low conflict choices). PDI patients and PD controls were tested on and off DA. RESULTS On the EDT, there was a group by medication interaction effect [F(1,26) = 5.62; p = 0.03] with pairwise analyses demonstrating that DA status was associated with increased impulsive choice in PDI patients (p = 0.02) but not in PD controls (p = 0.37). PDI patients also had faster RT compared to PD controls [F(1,26) = 7.51, p = 0.01]. DA status was associated with shorter RT [F(3,24) = 8.39, p = 0.001] and decision conflict RT [F(1,26) = 6.16, p = 0.02] in PDI patients but not in PD controls. There were no correlations between different measures of impulsivity. PDI patients on DA had greater spatial working memory impairments compared to PD controls on DA (t = 2.13, df = 26, p = 0.04). CONCLUSION Greater impulsive choice, faster RT, faster decision conflict RT, and executive dysfunction may contribute to ICDs in PD.
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Affiliation(s)
- Valerie Voon
- National Institutes of Health, 10 Center Drive, Bldg 10/Rm 7D37, Bethesda, MD 20892-1428, USA.
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Leo D, Adriani W, Cavaliere C, Cirillo G, Marco EM, Romano E, di Porzio U, Papa M, Perrone-Capano C, Laviola G. Methylphenidate to adolescent rats drives enduring changes of accumbal Htr7 expression: implications for impulsive behavior and neuronal morphology. GENES BRAIN AND BEHAVIOR 2009; 8:356-68. [DOI: 10.1111/j.1601-183x.2009.00486.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Psychopharmacological studies have implicated the mesolimbic dopamine (DA) system in the mediation of cost/benefit evaluations about delay or effort-related costs associated with larger rewards. However, the role of DA in risk-based decision making remains relatively unexplored. The present study investigated the effects of systemic manipulations of DA transmission on risky choice using a probabilistic discounting task. Over discrete trials, rats chose between two levers; a press on the 'small/certain' lever always delivered one reward pellet, whereas a press on the other, 'large/risky' lever delivered four pellets, but the probability of receiving reward decreased across the four trial blocks (100, 50, 25, 12.5%). In separate groups of well-trained rats we assessed the effects of the DA releaser amphetamine, as well as receptor selective agonists and antagonists. Amphetamine consistently increased preference for the large/risky lever; an effect that was blocked or attenuated by co-administration of either D(1) (SCH23390) or D(2) (eticlopride) receptor antagonists. Blockade of either of these receptors alone induced risk aversion. Conversely, stimulation of D(1) (SKF81297) or D(2) (bromocriptine) receptors also increased risky choice. In contrast, activation of D(3) receptors with PD128,907 reduced choice of the large/risky lever. Likewise, D(3) antagonism with nafadotride potentiated the amphetamine-induced increase in risky choice. Blockade or stimulation of D(4) receptors did not reliably alter behavior. These findings indicate that DA has a critical role in mediating risk-based decision making, with increased activation of D(1) and D(2) receptors biasing choice toward larger, probabilistic rewards, whereas D(3) receptors appear to exert opposing effects on this form of decision making.
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A meta-analysis of D-cycloserine and the facilitation of fear extinction and exposure therapy. Biol Psychiatry 2008; 63:1118-26. [PMID: 18313643 DOI: 10.1016/j.biopsych.2008.01.012] [Citation(s) in RCA: 337] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2007] [Revised: 01/14/2008] [Accepted: 01/14/2008] [Indexed: 12/18/2022]
Abstract
BACKGROUND Translational research suggests that D-cycloserine (DCS), a partial N-methyl-D-aspartate (NMDA) receptor agonist, might facilitate fear extinction and exposure therapy by either enhancing NMDA receptor function during extinction or by reducing NMDA receptor function during fear memory consolidation. This article provides a quantitative review of DCS-augmented fear extinction and exposure therapy literature. METHODS English-language journal articles that examined DCS augmented with fear extinction or exposure therapy were identified through public databases from June 1998 through September 2007, through references of originally identified articles and contact with DCS investigators. Data were extracted for study author, title, and year; trial design; type of subject (animal vs. human; clinical vs. nonclinical); sample size, DCS dose, and timing in relation to extinction/exposure procedures; dependent variable; group means and SDs at post-extinction/exposure; and follow-up outcome. RESULTS D-cycloserine enhances fear extinction/exposure therapy in both animals and anxiety-disordered humans. Gains generally were maintained at follow-up, although some lessening of efficacy was noted. D-cycloserine was more effective when administered a limited number of times and when given immediately before or after extinction training/exposure therapy. CONCLUSIONS This meta-analysis suggests that DCS is a useful target for translational research on augmenting exposure-based treatment via compounds that impact neuroplasticity. D-cycloserine 's major contribution to exposure-based therapy might be to increase its speed or efficiency, because the effects of DCS seem to decrease over repeated sessions. This information might guide translational researchers in discovering more selective and/or effective agents that effectively enhance (or reduce) NMDA receptor function.
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