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Involvement of DR→mPFC 5-HTergic neural projections in changes of social exploration behaviors caused by adult chronic social isolation in mice. Brain Res Bull 2022; 186:16-26. [DOI: 10.1016/j.brainresbull.2022.04.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 04/28/2022] [Accepted: 04/30/2022] [Indexed: 11/23/2022]
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Desrochers SS, Spring MG, Nautiyal KM. A Role for Serotonin in Modulating Opposing Drive and Brake Circuits of Impulsivity. Front Behav Neurosci 2022; 16:791749. [PMID: 35250501 PMCID: PMC8892181 DOI: 10.3389/fnbeh.2022.791749] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 01/11/2022] [Indexed: 12/15/2022] Open
Abstract
Impulsivity generally refers to a deficit in inhibition, with a focus on understanding the neural circuits which constitute the “brake” on actions and gratification. It is likely that increased impulsivity can arise not only from reduced inhibition, but also from a heightened or exaggerated excitatory “drive.” For example, an action which has more vigor, or is fueled by either increased incentive salience or a stronger action-outcome association, may be harder to inhibit. From this perspective, this review focuses on impulse control as a competition over behavioral output between an initially learned response-reward outcome association, and a subsequently acquired opposing inhibitory association. Our goal is to present a synthesis of research from humans and animal models that supports this dual-systems approach to understanding the behavioral and neural substrates that contribute to impulsivity, with a focus on the neuromodulatory role of serotonin. We review evidence for the role of serotonin signaling in mediating the balance of the “drive” and “brake” circuits. Additionally, we consider parallels of these competing instrumental systems in impulsivity within classical conditioning processes (e.g., extinction) in order to point us to potential behavioral and neural mechanisms that may modulate the competing instrumental associations. Finally, we consider how the balance of these competing associations might contribute to, or be extracted from, our experimental assessments of impulsivity. A careful understanding of the underlying behavioral and circuit level contributions to impulsivity is important for understanding the pathogenesis of increased impulsivity present in a number of psychiatric disorders. Pathological levels of impulsivity in such disorders are likely subserved by deficits in the balance of motivational and inhibitory processes.
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Rinehart L, Spencer S. Which came first: Cannabis use or deficits in impulse control? Prog Neuropsychopharmacol Biol Psychiatry 2021; 106:110066. [PMID: 32795592 PMCID: PMC7750254 DOI: 10.1016/j.pnpbp.2020.110066] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/12/2020] [Accepted: 08/05/2020] [Indexed: 12/16/2022]
Abstract
Impulse control deficits are often found to co-occur with substance use disorders (SUDs). On the one hand, it is well known that chronic intake of drugs of abuse remodels the brain with significant consequences for a range of cognitive behaviors. On the other hand, individual variation in impulse control may contribute to differences in susceptibility to SUDs. Both of these relationships have been described, thus leading to a "chicken or the egg" debate which remains to be fully resolved. Does impulsivity precede drug use or does it manifest as a function of problematic drug usage? The link between impulsivity and SUDs has been most strongly established for cocaine and alcohol use disorders using both preclinical models and clinical data. Much less is known about the potential link between impulsivity and cannabis use disorder (CUD) or the directionality of this relationship. The initiation of cannabis use occurs most often during adolescence prior to the brain's maturation, which is recognized as a critical period of development. The long-term effects of chronic cannabis use on the brain and behavior have started to be explored. In this review we will summarize these observations, especially as they pertain to the relationship between impulsivity and CUD, from both a psychological and biological perspective. We will discuss impulsivity as a multi-dimensional construct and attempt to reconcile the results obtained across modalities. Finally, we will discuss possible avenues for future research with emerging longitudinal data.
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Affiliation(s)
- Linda Rinehart
- University of Minnesota, Department of Psychiatry and Behavioral Sciences
| | - Sade Spencer
- University of Minnesota, Department of Pharmacology, Minneapolis, MN, USA.
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Impulsive prepotent actions and tics in Tourette disorder underpinned by a common neural network. Mol Psychiatry 2021; 26:3548-3557. [PMID: 32994553 PMCID: PMC8505252 DOI: 10.1038/s41380-020-00890-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 08/25/2020] [Accepted: 09/14/2020] [Indexed: 01/25/2023]
Abstract
Tourette disorder (TD), which is characterized by motor and vocal tics, is not in general considered as a product of impulsivity, despite a frequent association with attention deficit hyperactivity disorder and impulse control disorders. It is unclear which type of impulsivity, if any, is intrinsically related to TD and specifically to the severity of tics. The waiting type of motor impulsivity, defined as the difficulty to withhold a specific action, shares some common features with tics. In a large group of adult TD patients compared to healthy controls, we assessed waiting motor impulsivity using a behavioral task, as well as structural and functional underpinnings of waiting impulsivity and tics using multi-modal neuroimaging protocol. We found that unmedicated TD patients showed increased waiting impulsivity compared to controls, which was independent of comorbid conditions, but correlated with the severity of tics. Tic severity did not account directly for waiting impulsivity, but this effect was mediated by connectivity between the right orbito-frontal cortex with caudate nucleus bilaterally. Waiting impulsivity in unmedicated patients with TD also correlated with a higher gray matter signal in deep limbic structures, as well as connectivity with cortical and with cerebellar regions on a functional level. Neither behavioral performance nor structural or functional correlates were related to a psychometric measure of impulsivity or impulsive behaviors in general. Overall, the results suggest that waiting impulsivity in TD was related to tic severity, to functional connectivity of orbito-frontal cortex with caudate nucleus and to structural changes within limbic areas.
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Lundgren KA, Abbey-Lee RN, Garnham LC, Kreshchenko A, Ryding S, Løvlie H. Manipulating monoamines reduces exploration and boldness of Mediterranean field crickets. Behav Processes 2020; 183:104298. [PMID: 33347960 DOI: 10.1016/j.beproc.2020.104298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 12/02/2020] [Accepted: 12/16/2020] [Indexed: 10/22/2022]
Abstract
Despite the prevalence and research interest of animal personality, its underlying mechanisms are not yet fully understood. Due to the essential role of monoamines in modulating behaviour, we manipulated the monoaminergic systems of Mediterranean field crickets (Gryllus bimaculatus) to explore whether this altered behavioural responses commonly used to describe animal personality. Previous work has shown that both serotonin and dopamine manipulations can alter cricket behaviour, although results differ depending on the drug in focus. Here, we investigate the effect of Fluphenazine, a dopamine antagonist which also interacts with serotonin receptors, on activity, exploration, boldness, and aggression. These results are compared with those of our earlier work that investigated the effect of drugs that more specifically target serotonin or dopamine systems (Fluoxetine and Ropinirole, respectively). Due to limited research on dose-effects of Fluphenazine, we created dose-response curves with concentrations ranging from those measured in surface waters up to human therapeutic doses. We show that compared to control animals, Fluphenazine manipulation resulted in lower levels of both exploration and boldness, but did not affect activity nor aggression. The effect on explorative behaviour contradicts our previous results of serotonin and dopamine manipulations. These results together confirm the causal role of monoamines in explaining variation in behaviour often used to describe animal personality, effects that can be both dose- and behaviour-dependent. Further, our results suggest that previous results assigned specifically to the dopaminergic system, may at least partly be explained by effects of the serotonergic system. Thus, future studies should continue to investigate the explicit underlying roles of specific monoamines in explaining behavioural variation.
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Affiliation(s)
- Kristoffer A Lundgren
- Department of Physics, Chemistry and Biology, IFM Biology, Linköping University, 58381 Linköping, Sweden
| | - Robin N Abbey-Lee
- Department of Physics, Chemistry and Biology, IFM Biology, Linköping University, 58381 Linköping, Sweden
| | - Laura C Garnham
- Department of Physics, Chemistry and Biology, IFM Biology, Linköping University, 58381 Linköping, Sweden
| | - Anastasia Kreshchenko
- Department of Physics, Chemistry and Biology, IFM Biology, Linköping University, 58381 Linköping, Sweden; School of Biological Sciences, University of Manchester, M13 9PL Manchester, UK
| | - Sara Ryding
- Department of Physics, Chemistry and Biology, IFM Biology, Linköping University, 58381 Linköping, Sweden; School of Biological Sciences, University of Manchester, M13 9PL Manchester, UK
| | - Hanne Løvlie
- Department of Physics, Chemistry and Biology, IFM Biology, Linköping University, 58381 Linköping, Sweden.
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Yates JR. Examining the neurochemical underpinnings of animal models of risky choice: Methodological and analytic considerations. Exp Clin Psychopharmacol 2019; 27:178-201. [PMID: 30570275 PMCID: PMC6467223 DOI: 10.1037/pha0000239] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Because risky choice is associated with several psychiatric conditions, recent research has focused on examining the underlying neurochemical processes that control risk-based decision-making. Not surprisingly, several tasks have been developed to study the neural mechanisms involved in risky choice. The current review will briefly discuss the major tasks used to measure risky choice and will summarize the contribution of several major neurotransmitter systems to this behavior. To date, the most common measures of risky choice are the probability discounting task, the risky decision task, and the rat gambling task. Across these three tasks, the contribution of the dopaminergic system has been most studied, although the effects of serotonergic, adrenergic, cholinergic, and glutamatergic ligands will be discussed. Drug effects across these tasks have been inconsistent, which makes determining the precise role of neurotransmitter systems in risky choice somewhat difficult. Furthermore, procedural differences can modulate drug effects in these procedures, and the way data are analyzed can alter the interpretations one makes concerning pharmacological manipulations. By taking these methodological/analytic considerations into account, we may better elucidate the neurochemistry of risky decision-making. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
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Korte-Bouws GAH, Albers E, Voskamp M, Hendriksen H, de Leeuw LR, Güntürkün O, de Roock S, Vastert SJ, Korte SM. Juvenile Arthritis Patients Suffering from Chronic Inflammation Have Increased Activity of Both IDO and GTP-CH1 Pathways But Decreased BH4 Efficacy: Implications for Well-Being, Including Fatigue, Cognitive Impairment, Anxiety, and Depression. Pharmaceuticals (Basel) 2019; 12:E9. [PMID: 30625990 PMCID: PMC6469185 DOI: 10.3390/ph12010009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 12/24/2018] [Accepted: 12/29/2018] [Indexed: 12/27/2022] Open
Abstract
Juvenile idiopathic arthritis (JIA) represents joint inflammation with an unknown cause that starts before the age of 16, resulting in stiff and painful joints. In addition, JIA patients often report symptoms of sickness behavior. Recent animal studies suggest that proinflammatory cytokines produce sickness behavior by increasing the activity of indoleamine-2,3-dioxygenase (IDO) and guanosinetriphosphate⁻cyclohydrolase-1 (GTP⁻CH1). Here, it is hypothesized that inflammation in JIA patients enhances the enzymatic activity of IDO and GTP-CH1 and decreases the co-factor tetrahydrobiopterin (BH4). These compounds play a crucial role in the synthesis and metabolism of neurotransmitters. The aim of our study was to reveal whether inflammation affects both the GTP-CH1 and IDO pathway in JIA patients. Serum samples were collected from twenty-four JIA patients. In these samples, the concentrations of tryptophan (TRP), kynurenine (KYN), tyrosine (TYR), neopterin, and phenylalanine (PHE) were measured. An HPLC method with electrochemical detection was developed to quantify tryptophan, kynurenine, and tyrosine. Neopterin and phenylalanine were quantified by ELISA. The KYN/TRP ratio was measured as an index of IDO activity, while the PHE/TYR ratio was measured as an index of BH4 activity. Neopterin concentrations were used as an indirect measure of GTP-CH1 activity. JIA patients with high disease activity showed higher levels of both neopterin and kynurenine, and a higher ratio of both KYN/TRP and PHE/TYR and lower tryptophan levels than clinically inactive patients. Altogether, these data support our hypothesis that inflammation increases the enzymatic activity of both IDO and GTP-CH1 but decreases the efficacy of the co-factor BH4. In the future, animal studies are needed to investigate whether inflammation-induced changes in these enzymatic pathways and co-factor BH4 lower the levels of the brain neurotransmitters glutamate, noradrenaline, dopamine, serotonin, and melatonin, and consequently, whether they may affect fatigue, cognition, anxiety, and depression. Understanding of these complex neuroimmune interactions provides new possibilities for Pharma-Food interventions to improve the quality of life of patients suffering from chronic inflammation.
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Affiliation(s)
- Gerdien A H Korte-Bouws
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Faculty of Science, Universities 99, 3584 CG Utrecht, The Netherlands.
| | - Eline Albers
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Faculty of Science, Universities 99, 3584 CG Utrecht, The Netherlands.
| | - Marije Voskamp
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Faculty of Science, Universities 99, 3584 CG Utrecht, The Netherlands.
| | - Hendrikus Hendriksen
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Faculty of Science, Universities 99, 3584 CG Utrecht, The Netherlands.
| | - Lidewij R de Leeuw
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Faculty of Science, Universities 99, 3584 CG Utrecht, The Netherlands.
| | - Onur Güntürkün
- Department of Biopsychology, Faculty of Psychology, Ruhr-Universität Bochum, Universitätsstraße 150, D-44780 Bochum, Germany.
| | - Sytze de Roock
- Paediatric Rheumatology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Lundlaan 6, 3584 EA Utrecht, The Netherlands.
| | - Sebastiaan J Vastert
- Paediatric Rheumatology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Lundlaan 6, 3584 EA Utrecht, The Netherlands.
| | - S Mechiel Korte
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Faculty of Science, Universities 99, 3584 CG Utrecht, The Netherlands.
- Department of Biopsychology, Faculty of Psychology, Ruhr-Universität Bochum, Universitätsstraße 150, D-44780 Bochum, Germany.
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de Haas EN, van der Eijk JA. Where in the serotonergic system does it go wrong? Unravelling the route by which the serotonergic system affects feather pecking in chickens. Neurosci Biobehav Rev 2018; 95:170-188. [DOI: 10.1016/j.neubiorev.2018.07.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 07/09/2018] [Accepted: 07/10/2018] [Indexed: 12/16/2022]
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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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McLaughlin T, Blum K, Steinberg B, Modestino EJ, Fried L, Baron D, Siwicki D, Braverman ER, Badgaiyan RD. Pro-dopamine regulator, KB220Z, attenuates hoarding and shopping behavior in a female, diagnosed with SUD and ADHD. J Behav Addict 2018; 7:192-203. [PMID: 29316800 PMCID: PMC6035027 DOI: 10.1556/2006.6.2017.081] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Background Addictive-like behaviors (e.g., hoarding and shopping) may be the result of the cumulative effects of dopaminergic and other neurotransmitter genetic variants as well as elevated stress levels. We, therefore, propose that dopamine homeostasis may be the preferred goal in combating such challenging and unwanted behaviors, when simple dopaminergic activation through potent agonists may not provide any resolution. Case presentation C.J. is a 38-year-old, single, female, living with her mother. She has a history of substance use disorder as well as attention deficit hyperactivity disorder, inattentive type. She had been stable on buprenorphine/naloxone combination and amphetamine, dextroamphetamine mixed salts for many years when unexpectedly she lost her job for oversleeping and not calling into work. KB200z (a pro-dopamine compound) was added to her regimen for complaints of low drive and motivation. After taking this nutraceutical for 4 weeks, she noticed a marked improvement in her mental status and many behaviors. She noted that her shopping and hoarding addictions had appreciably decreased. Furthermore, her lifelong history of terrifying lucid dreams was eliminated. Finally, she felt more in control; her locus of control shifted from external to more internal. Discussion The hypothesis is that C.J.'s reported, behavioral, and psychological benefits resulted from the pro-dopamine-regulating effect of KB220Z across the brain reward system. Conclusions This effect, we surmise, could be the result of a new dopamine balance, across C.J.'s brain reward system. Dopamine homeostasis is an effect of KB220Z seen in both animal and human placebo-controlled fMRI experiments.
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Affiliation(s)
- Thomas McLaughlin
- 1 Department of Psychopharmacology, Center for Psychiatric Medicine , Lawrence, MA, USA
| | - Kenneth Blum
- 2 Department of Psychiatry, Boonshoft School of Medicine, Dayton VA Medical Center, Wright State University , Dayton, OH, USA
- 3 Department of Psychiatry, McKnight Brain Institute, University of Florida College of Medicine , Gainesville, FL, USA
- 4 Department of Psychiatry and Behavioral Sciences, Keck Medicine University of Southern California , Los Angeles, CA, USA
- 5 Division of Applied Clinical Research & Education, Dominion Diagnostics, LLC , North Kingstown, RI, USA
- 6 Department of Precision Medicine, Geneus Health LLC , San Antonio, TX, USA
- 7 Department of Addiction Research & Therapy, Nupathways Inc. , Innsbrook, MO, USA
- 8 Department of Clinical Neurology, Path Foundation , New York, NY, USA
- 9 Division of Neuroscience Based Addiction Therapy, The Shores Treatment & Recovery Center , Port Saint Lucie, FL, USA
- 10 Institute of Psychology, Eötvös Loránd University , Budapest, Hungary
| | - Bruce Steinberg
- 11 Department of Psychology, Curry College , Milton, MA, USA
| | | | - Lyle Fried
- 9 Division of Neuroscience Based Addiction Therapy, The Shores Treatment & Recovery Center , Port Saint Lucie, FL, USA
| | - David Baron
- 4 Department of Psychiatry and Behavioral Sciences, Keck Medicine University of Southern California , Los Angeles, CA, USA
| | - David Siwicki
- 6 Department of Precision Medicine, Geneus Health LLC , San Antonio, TX, USA
| | - Eric R Braverman
- 8 Department of Clinical Neurology, Path Foundation , New York, NY, USA
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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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12
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Zhong H, Dang J, Huo Z, Ma Z, Chen J, Huang Y, Zhu Y, Li M. Effects of medial prefrontal cortex 5-HT 7 receptor knockdown on cognitive control after acute heroin administration. Brain Res 2017; 1678:419-431. [PMID: 29155092 DOI: 10.1016/j.brainres.2017.11.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 10/28/2017] [Accepted: 11/01/2017] [Indexed: 10/18/2022]
Abstract
Heroin abuse is linked to a deleterious effect on cognitive functioning in the individual. Recent evidences suggest that the serotonin7 receptor (5-HT7R) is engaged in the regulation of cognitive control and the drug use-associated behaviors. However, the role of 5-HT7R in the cognitive control after acute heroin administration has not been studied. The present study aims to investigate whether the knockdown of the 5-HT7R by virus-mediated gene silencing in the medial prefrontal cortex (mPFC) could ameliorate the acute heroin-induced cognitive impairments. The attentional function, impulsivity and compulsivity were assessed by the 5-choice serial reaction time task (5-CSRTT) in mice. The memory ability and locomotor activity were examined by the novel objects recognition (NOR), Y-maze and open-field test (OFT). Acute heroin administration at 5 mg/kg produced robust disruptions in attention, impulsivity and motivation in mice. 5-HT7R knockdown in the mPFC did not affect the 5-CSRTT baseline performance, spatial working memory, visual episodic memory and locomotion. However, mPFC 5-HT7R knockdown selectively ameliorated acute heroin-induced increase in omissions and premature responses under conditions of increased perceptual load. In addition, mPFC 5-HT7R knockdown induced increases in perseverative responding observed across both saline and heroin-treated animals. Moreover, 5-HT7R knockdown prevented the heroin-induced decrease in NR1/CaMKII phosphorylation in mPFC, thus suggesting that 5-HT7R and N-methyl-d-aspartic acid (NMDA) receptor signaling may be involved in the cognitive outcomes of acute heroin administration. Altogether, these observations suggest modest and restricted effects of mPFC 5-HT7R knockdown on cognitive behaviors, both in the presence or absence of acute heroin treatment.
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Affiliation(s)
- Huijun Zhong
- Key Laboratory of Fertility Preservation and Maintenance of Ministry of Education & Key Laboratory of Reproduction and Genetics, Department of Medical Genetic and Cell Biology, Ningxia Medical University, China
| | - Jie Dang
- Key Laboratory of Fertility Preservation and Maintenance of Ministry of Education & Key Laboratory of Reproduction and Genetics, Department of Medical Genetic and Cell Biology, Ningxia Medical University, China
| | - Zhenghao Huo
- Key Laboratory of Fertility Preservation and Maintenance of Ministry of Education & Key Laboratory of Reproduction and Genetics, Department of Medical Genetic and Cell Biology, Ningxia Medical University, China.
| | - Zhanbing Ma
- Key Laboratory of Fertility Preservation and Maintenance of Ministry of Education & Key Laboratory of Reproduction and Genetics, Department of Medical Genetic and Cell Biology, Ningxia Medical University, China
| | - Jing Chen
- Key Laboratory of Fertility Preservation and Maintenance of Ministry of Education & Key Laboratory of Reproduction and Genetics, Department of Medical Genetic and Cell Biology, Ningxia Medical University, China
| | - Yong Huang
- Department of Nuclear Medicine, Tangdu Hospital, The Fourth Military Medical University, China
| | - Yongsheng Zhu
- College of Forensic Science, Xi'an Jiao Tong University, China
| | - Min Li
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, China
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