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Liu Q, Ilčíková T, Radchenko M, Junková M, Špinka M. Effects of reduced kinematic and social play experience on affective appraisal of human-rat play in rats. Front Zool 2023; 20:34. [PMID: 37821980 PMCID: PMC10568924 DOI: 10.1186/s12983-023-00512-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 09/30/2023] [Indexed: 10/13/2023] Open
Abstract
BACKGROUND Play is a common and developmentally important behaviour in young mammals. Specifically in Norway rats (Rattus norvegicus), reduced opportunity to engage in rough-and-tumble (RT) play has been associated with impaired development in social competence. However, RT play is a complex behaviour having both a kinematic aspect (i.e., performing complex 3D manoeuvres during play fights) and a social aspect (interacting with a playful partner). There has been little research so far on disentangling the two aspects in RT play, especially on how these two aspects affect the affective appraisal of the intense physical contact during play. RESULTS To examine the developmental effects of kinematic and social play reduction on affective appraisal in rats, we subjected male Long-Evans rats from 21 days old to RT play experience that was reduced either kinematically (through playing in a low ceiling environment) or socially (through playing with a less playful Fischer-344 rat). Starting at 35 days, we measured their production of positively (50-kHz) and negatively (22-kHz) valenced ultrasonic vocalisations (USVs) in a 2-min standardised human-rat play procedure that mimicked the playful sequences of nape contact, pinning, and belly stimulation ('tickling') for ten days. We hypothesised that the rats with kinematically or socially reduced play would perceive the 'tickling' less positively and thus emit positive ultrasonic vocalisations at lower rates compared to control rats with non-reduced play experience. Our results confirmed that each of the treatments reduced play differently: while the kinematic reduction abolished playful pinnings entirely, the social reduction decreased the pinnings and made play highly asymmetric. During the tickling procedure, rats mostly produced 50 kHz USV, indicating that they appraised the procedure as positive. There was a wide inter individual variance and high individual consistency in rats' USV responses to 'tickling'. Crucially, neither the kinematically nor the socially reduced play experience affected either type of USV production when rats were 'tickled'. CONCLUSIONS This finding indicates that the ability to appraise play-like interactions as positive remains unaffected even when the kinematic or the social aspect of play experience was substantially curtailed.
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Affiliation(s)
- Quanxiao Liu
- Department of Ethology and Companion Animal Science, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Prague, Czechia.
| | - Tereza Ilčíková
- Department of Ethology and Companion Animal Science, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Prague, Czechia
| | - Mariia Radchenko
- Department of Ethology and Companion Animal Science, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Prague, Czechia
| | - Markéta Junková
- Department of Ethology and Companion Animal Science, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Prague, Czechia
| | - Marek Špinka
- Department of Ethology and Companion Animal Science, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Prague, Czechia
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2
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Zeid D, Toussaint AB, Dressler CC, Schumacher SP, Do C, Desalvo H, Selamawi D, Bongiovanni AR, Mayberry HL, Carr GV, Wimmer ME. Paternal morphine exposure in rats reduces social play in adolescent male progeny without affecting drug-taking behavior in juvenile males or female offspring. Mol Cell Neurosci 2023; 126:103877. [PMID: 37385516 PMCID: PMC10528482 DOI: 10.1016/j.mcn.2023.103877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 06/02/2023] [Accepted: 06/24/2023] [Indexed: 07/01/2023] Open
Abstract
The ongoing opioid addiction crisis necessitates the identification of novel risk factors to improve prevention and treatment of opioid use disorder. Parental opioid exposure has recently emerged as a potential regulator of offspring vulnerability to opioid misuse, in addition to heritable genetic liability. An understudied aspect of this "missing heritability" is the developmental presentation of these cross-generational phenotypes. This is an especially relevant question in the context of inherited addiction-related phenotypes, given the prominent role of developmental processes in the etiology of psychiatric disorders. Paternal morphine self-administration was previously shown to alter the sensitivity to the reinforcing and antinociceptive properties of opioids in the next generation. Here, phenotyping was expanded to include the adolescent period, with a focus on endophenotypes related to opioid use disorders and pain. Paternal morphine exposure did not alter heroin or cocaine self-administration in male and female juvenile progeny. Further, baseline sensory reflexes related to pain were unaltered in morphine-sired adolescent rats of either sex. However, morphine-sired adolescent males exhibited a reduction in social play behavior. Our findings suggest that, in morphine-sired male offspring, paternal opioid exposure does not affect opioid intake during adolescence, suggesting that this phenotype does not emerge until later in life. Altered social behaviors in male morphine-sired adolescents indicate that the changes in drug-taking behavior in adults sired by morphine-exposed sires may be due to more complex factors not yet fully assessed.
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Affiliation(s)
- Dana Zeid
- Department of Psychology and Neuroscience, College of Liberal Arts, Temple University, United States of America
| | - Andre B Toussaint
- Zuckerman Mind Brain Behavior Institute, Columbia University, United States of America
| | - Carmen C Dressler
- Department of Psychology and Neuroscience, College of Liberal Arts, Temple University, United States of America
| | - Samuel P Schumacher
- Department of Psychology and Neuroscience, College of Liberal Arts, Temple University, United States of America
| | - Chau Do
- Department of Psychology and Neuroscience, College of Liberal Arts, Temple University, United States of America
| | - Heather Desalvo
- Department of Psychology and Neuroscience, College of Liberal Arts, Temple University, United States of America
| | - Danait Selamawi
- Department of Psychology and Neuroscience, College of Liberal Arts, Temple University, United States of America
| | - Angela R Bongiovanni
- Department of Psychology and Neuroscience, College of Liberal Arts, Temple University, United States of America
| | - Hannah L Mayberry
- Department of Psychology and Neuroscience, College of Liberal Arts, Temple University, United States of America
| | - Gregory V Carr
- Lieber Institute of Brain Development, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, United States of America
| | - Mathieu E Wimmer
- Department of Psychology and Neuroscience, College of Liberal Arts, Temple University, United States of America.
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3
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Achterberg EJM, Vanderschuren LJMJ. The neurobiology of social play behaviour: Past, present and future. Neurosci Biobehav Rev 2023; 152:105319. [PMID: 37454882 DOI: 10.1016/j.neubiorev.2023.105319] [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: 03/03/2023] [Revised: 07/07/2023] [Accepted: 07/12/2023] [Indexed: 07/18/2023]
Abstract
Social play behaviour is a highly energetic and rewarding activity that is of great importance for the development of brain and behaviour. Social play is abundant during the juvenile and early adolescent phases of life, and it occurs in most mammalian species, as well as in certain birds and reptiles. To date, the majority of research into the neural mechanisms of social play behaviour has been performed in male rats. In the present review we summarize studies on the neurobiology of social play behaviour in rats, including work on pharmacological and genetic models for autism spectrum disorders, early life manipulations and environmental factors that influence play in rats. We describe several recent developments that expand the field, and highlight outstanding questions that may guide future studies.
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Affiliation(s)
- E J Marijke Achterberg
- Dept. of Population Health Sciences, Section Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 2, 3584 CM Utrecht, the Netherlands.
| | - Louk J M J Vanderschuren
- Dept. of Population Health Sciences, Section Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 2, 3584 CM Utrecht, the Netherlands.
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4
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Harder HJ, Searles CT, Vogt ME, Murphy AZ. Perinatal opioid exposure leads to decreased social play in adolescent male and female rats: Potential role of oxytocin signaling in brain regions associated with social reward. Horm Behav 2023; 153:105384. [PMID: 37295323 PMCID: PMC10330883 DOI: 10.1016/j.yhbeh.2023.105384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/26/2023] [Accepted: 05/23/2023] [Indexed: 06/12/2023]
Abstract
Over the last two decades, the number of infants exposed to opioids in utero has quadrupled in the United States, with some states reporting rates as high as 55 infants per 1000 births. Clinical studies report that children previously exposed to opioids during gestation show significant deficits in social behavior, including an inability to form friendships or other social relationships. To date, the neural mechanisms whereby developmental opioid exposure disrupts social behavior remain unknown. Using a novel paradigm of perinatal opioid administration, we tested the hypothesis that chronic opioid exposure during critical developmental periods would disrupt juvenile play. As oxytocin is a major regulator of sociability, the impact of perinatal morphine exposure on oxytocin peptide expression was also examined. Juvenile play was assessed in vehicle- or morphine-exposed male and female rats at P25, P35, and P45. Classical features of juvenile play were measured, including time spent engaged in social play, time not in contact, number of pins, and number of nape attacks. We report that morphine-exposed males and females spend less time engaged in play behavior than control males and females, with a corresponding increase in time spent alone. Morphine-exposed males and females also initiated fewer pins and nape attacks. Together, these data suggest that male and female rats exposed to morphine during critical developmental periods are less motivated to participate in social play, potentially due to alterations in oxytocin-mediated reward signaling.
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Affiliation(s)
- Hannah J Harder
- Neuroscience Institute, Georgia State University, 100 Piedmont Ave., Atlanta, GA 30303, United States of America
| | - Christopher T Searles
- Neuroscience Institute, Georgia State University, 100 Piedmont Ave., Atlanta, GA 30303, United States of America
| | - Meghan E Vogt
- Neuroscience Institute, Georgia State University, 100 Piedmont Ave., Atlanta, GA 30303, United States of America
| | - Anne Z Murphy
- Neuroscience Institute, Georgia State University, 100 Piedmont Ave., Atlanta, GA 30303, United States of America.
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5
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Harder HJ, Searles CT, Vogt ME, Murphy AZ. Perinatal Opioid Exposure Leads to Decreased Social Play in Adolescent Male and Female Rats: Potential Role of Oxytocin Signaling in Brain Regions Associated with Social Reward. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.10.532122. [PMID: 36945450 PMCID: PMC10028981 DOI: 10.1101/2023.03.10.532122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2023]
Abstract
Over the last two decades, the number of infants exposed to opioids in utero has quadrupled in the United States, with some states reporting rates as high as 55 infants per 1000 births. Clinical studies report that children previously exposed to opioids during gestation show significant deficits in social behavior, including an inability to form friendships or other social relationships. To date, the neural mechanisms whereby developmental opioid exposure disrupts social behavior remain unknown. Using a novel paradigm of perinatal opioid administration, we tested the hypothesis that chronic opioid exposure during critical developmental periods would disrupt juvenile play. As oxytocin is a major regulator of sociability, the impact of perinatal morphine exposure on oxytocin peptide and receptor expression was also examined. Juvenile play was assessed in vehicle- or morphine-exposed male and female rats at P25, P35, and P45. Classical features of juvenile play were measured, including time spent engaged in social play, time not in contact, number of pins, and number of nape attacks. We report that morphine-exposed females spend less time engaged in play behavior than control males and females, with a corresponding increase in time spent alone. Morphine-exposed females also initiated fewer pins and nape attacks. Oxytocin receptor binding was reduced in morphine-exposed females in the nucleus accumbens, a brain region critical for social reward. Together, these data suggest that females exposed to morphine during critical developmental periods are less motivated to participate in social play, potentially due to alterations in oxytocin-mediated reward signaling.
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6
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Riters LV, Stevenson SA. Using seasonality and birdsong to understand mechanisms underlying context-appropriate shifts in social motivation and reward. Horm Behav 2022; 142:105156. [PMID: 35313200 PMCID: PMC9382228 DOI: 10.1016/j.yhbeh.2022.105156] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 01/11/2022] [Accepted: 03/11/2022] [Indexed: 12/29/2022]
Abstract
Social motivation and reward are dynamic and flexible, shifting adaptively across contexts to meet changing social demands. This is exceptionally apparent when seasonal contexts are considered in seasonally breeding songbirds as they cycle from periods of sexual motivation and reward during the breeding season to periods of extreme gregariousness outside the breeding season when non-sexual social interactions gain reward value, motivating birds to form flocks. Here we review evidence demonstrating a key integrative role for the medial preoptic area (mPOA) in the seasonally-appropriate adjustment of behaviors, with seasonal changes in dopamine activity in mPOA adjusting social motivation and changes in opioid activity modifying social reward. Experiments demonstrate that dramatic seasonal fluctuations in steroid hormone concentrations alter patterns of opioid- and dopamine-related protein and gene expression in mPOA to modify social motivation and reward to meet seasonal changes in social demands. These studies of birdsong and seasonality provide new insights into neural and endocrine mechanisms underlying adaptive changes in social motivation and reward and highlight an underappreciated, evolutionarily conserved role for the mPOA in important social behaviors in non-reproductive contexts.
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Affiliation(s)
- Lauren V Riters
- Department of Integrative Biology, 428 Birge Hall, 430 Lincoln Drive, University of Wisconsin-Madison, Madison, WI 53706, USA.
| | - Sharon A Stevenson
- Department of Integrative Biology, 428 Birge Hall, 430 Lincoln Drive, University of Wisconsin-Madison, Madison, WI 53706, USA
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7
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Alexander R, Aragón OR, Bookwala J, Cherbuin N, Gatt JM, Kahrilas IJ, Kästner N, Lawrence A, Lowe L, Morrison RG, Mueller SC, Nusslock R, Papadelis C, Polnaszek KL, Helene Richter S, Silton RL, Styliadis C. The neuroscience of positive emotions and affect: Implications for cultivating happiness and wellbeing. Neurosci Biobehav Rev 2021; 121:220-249. [PMID: 33307046 DOI: 10.1016/j.neubiorev.2020.12.002] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 11/10/2020] [Accepted: 12/06/2020] [Indexed: 02/07/2023]
Abstract
This review paper provides an integrative account regarding neurophysiological correlates of positive emotions and affect that cumulatively contribute to the scaffolding for happiness and wellbeing in humans and other animals. This paper reviews the associations among neurotransmitters, hormones, brain networks, and cognitive functions in the context of positive emotions and affect. Consideration of lifespan developmental perspectives are incorporated, and we also examine the impact of healthy social relationships and environmental contexts on the modulation of positive emotions and affect. The neurophysiological processes that implement positive emotions are dynamic and modifiable, and meditative practices as well as flow states that change patterns of brain function and ultimately support wellbeing are also discussed. This review is part of "The Human Affectome Project" (http://neuroqualia.org/background.php), and in order to advance a primary aim of the Human Affectome Project, we also reviewed relevant linguistic dimensions and terminology that characterizes positive emotions and wellbeing. These linguistic dimensions are discussed within the context of the neuroscience literature with the overarching goal of generating novel recommendations for advancing neuroscience research on positive emotions and wellbeing.
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Affiliation(s)
- Rebecca Alexander
- Neuroscience Research Australia, Randwick, Sydney, NSW, 2031, Australia; Australian National University, Canberra, ACT, 2601, Australia
| | - Oriana R Aragón
- Yale University, 2 Hillhouse Ave, New Haven, CT, 06520, USA; Clemson University, 252 Sirrine Hall, Clemson, SC, 29634, USA
| | - Jamila Bookwala
- Department of Psychology and Program in Aging Studies, Lafayette College, 730 High Road, Easton, PA, USA
| | - Nicolas Cherbuin
- Centre for Research on Ageing, Health, and Wellbeing, Australian National University, Canberra, ACT, 2601, Australia
| | - Justine M Gatt
- Neuroscience Research Australia, Randwick, Sydney, NSW, 2031, Australia; School of Psychology, University of New South Wales, Randwick, Sydney, NSW, 2031, Australia
| | - Ian J Kahrilas
- Department of Psychology, Loyola University Chicago, 1032 W. Sheridan Road, Chicago, IL, 60660, USA
| | - Niklas Kästner
- Department of Behavioural Biology, University of Münster, Badestraße 13, 48149, Münster, Germany
| | - Alistair Lawrence
- Scotland's Rural College, King's Buildings, Edinburgh, EH9 3JG, United Kingdom; The Roslin Institute, University of Edinburgh, Easter Bush, EH25 9RG, United Kingdom
| | - Leroy Lowe
- Neuroqualia (NGO), Truro, NS, B2N 1X5, Canada
| | - Robert G Morrison
- Department of Psychology, Loyola University Chicago, 1032 W. Sheridan Road, Chicago, IL, 60660, USA
| | - Sven C Mueller
- Department of Experimental Clinical and Health Psychology, Ghent University, Ghent, Belgium; Department of Personality, Psychological Assessment and Treatment, University of Deusto, Bilbao, Spain
| | - Robin Nusslock
- Department of Psychology and Institute for Policy Research, Northwestern University, 2029 Sheridan Road, Evanston, IL, 60208, USA
| | - Christos Papadelis
- Jane and John Justin Neurosciences Center, Cook Children's Health Care System, 1500 Cooper St, Fort Worth, TX, 76104, USA; Laboratory of Children's Brain Dynamics, Division of Newborn Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Kelly L Polnaszek
- Department of Psychology, Loyola University Chicago, 1032 W. Sheridan Road, Chicago, IL, 60660, USA
| | - S Helene Richter
- Department of Behavioural Biology, University of Münster, Badestraße 13, 48149, Münster, Germany
| | - Rebecca L Silton
- Department of Psychology, Loyola University Chicago, 1032 W. Sheridan Road, Chicago, IL, 60660, USA; Institute for Innovations in Developmental Sciences, Northwestern University, 633 N. Saint Clair, Chicago, IL, 60611, USA.
| | - Charis Styliadis
- Neuroscience of Cognition and Affection group, Lab of Medical Physics, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece
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8
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Abstract
Domestic ferrets (Mustela putorius furo) are common zoologic companion animals and display specific body language and vocalizations. Social interactions, play behavior, and resting periods are important keystone in domestic ferret behavior. Specific housing and environmental enrichment are recommended to preserve the expression of normal behavior and physiology in ferrets. Presence of abnormal behaviors, including aggression, urination and defecation outside the litter box, stereotypies, and absence of play behavior, should be carefully monitored by veterinarians and ferret owners to assess ferret wellness. Specific considerations, such as deafness, poor vision, and hybridation with other mustelids, may play a role in ferret behavior.
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9
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Zhao C, Chang L, Auger AP, Gammie SC, Riters LV. Mu opioid receptors in the medial preoptic area govern social play behavior in adolescent male rats. GENES BRAIN AND BEHAVIOR 2020; 19:e12662. [PMID: 32388931 DOI: 10.1111/gbb.12662] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/27/2020] [Accepted: 04/28/2020] [Indexed: 12/16/2022]
Abstract
Neural systems underlying important behaviors are usually highly conserved across species. The medial preoptic area (MPOA) has been demonstrated to play a crucial role in reward associated with affiliative, nonsexual, social communication in songbirds. However, the role of MPOA in affiliative, rewarding social behaviors (eg, social play behavior) in mammals remains largely unknown. Here we applied our insights from songbirds to rats to determine whether opioids in the MPOA govern social play behavior in rats. Using an immediate early gene (ie, Egr1, early growth response 1) expression approach, we identified increased numbers of Egr1-labeled cells in the MPOA after social play in adolescent male rats. We also demonstrated that cells expressing mu opioid receptors (MORs, gene name Oprm1) in the MPOA displayed increased Egr1 expression when adolescent rats were engaged in social play using double immunofluorescence labeling of MOR and Egr1. Furthermore, using short hairpin RNA-mediated gene silencing we revealed that knockdown of Oprm1 in the MPOA reduced the number of total play bouts and the frequency of pouncing. Last, RNA sequencing differential gene expression analysis identified genes involved in neuronal signaling with altered expression after Oprm1 knockdown, and identified Egr1 as potentially a key modulator for Oprm1 in the regulation of social play behavior. Altogether, these results show that the MPOA is involved in social play behavior in adolescent male rats and support the hypothesis that the MPOA is part of a conserved neural circuit across vertebrates in which opioids act to govern affiliative, intrinsically rewarded social behaviors.
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Affiliation(s)
- Changjiu Zhao
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Liza Chang
- Department of Psychology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Anthony P Auger
- Department of Psychology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Stephen C Gammie
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Lauren V Riters
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, Wisconsin, USA
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10
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Ševčíková M, Petríková I, Šlamberová R. Methamphetamine exposure during the first, but not the second half of prenatal development, affects social play behavior. Physiol Res 2020; 69:319-330. [PMID: 32199010 DOI: 10.33549/physiolres.934230] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Methamphetamine (MA), as a psychostimulant drug that crosses the placental barrier, may disrupt the development of social play. The present study aims to examine the effect of prenatal MA (5 mg/kg) exposure during the first (gestational day (GD) 1-11) or second (GD 12-22) halves of prenatal development of rats on social play behavior. To investigate an acute effect of MA on social play in adulthood, juvenile rats were exposed to a dose of 1 mg/kg MA or saline on the test day and tested for social play for 15 min. Prenatal exposure to MA during GD 1-11 increased social play behavior during 5-10 min interval of the test in males but not females. Prenatal MA during GD 12-22 did not influence social play in males nor females. However, social play occurred to a greater extent in GD 12-22 groups compared with GD 1-11. Acute exposure to MA eliminated playful behavior in all groups and decreased social exploration in GD 1-11. Our results suggest that manipulation of prenatal development during the first half of the gestational period has a greater impact on social play behavior than during the second half.
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Affiliation(s)
- M Ševčíková
- Department of Physiology, Third Faculty of Medicine, Charles University, Prague, Czech Republic.
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11
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Løseth GE, Eikemo M, Leknes S. Effects of opioid receptor stimulation and blockade on touch pleasantness: a double-blind randomised trial. Soc Cogn Affect Neurosci 2020; 14:411-422. [PMID: 30951167 PMCID: PMC6523440 DOI: 10.1093/scan/nsz022] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 02/21/2019] [Accepted: 03/23/2019] [Indexed: 11/23/2022] Open
Abstract
The μ-opioid receptor (MOR) system has long been thought to underpin the rewarding properties of pleasant touch. Numerous non-human animal studies implicate MORs in social behaviours involving touch, but little is currently known about MOR involvement in human touch reward. Here, we employed a bi-directional pharmacological double-blind crossover design to assess the role of the human MOR system for touch pleasantness and motivation. Forty-nine male volunteers received 10 mg per-oral morphine, 50 mg per-oral naltrexone and placebo before being brushed on their forearm at three different velocities (0.3, 3 and 30 cm/s). In a touch liking task, pleasantness ratings were recorded after each 15 s brushing trial. In a touch wanting task, participants actively manipulated trial duration through key presses. As expected, 3 cm/s was the preferred velocity, producing significantly higher pleasantness ratings and wanting scores than the other stimuli. Contrary to our hypothesis, MOR drug manipulations did not significantly affect either touch pleasantness or wanting. The null effects were supported by post hoc Bayesian analyses indicating that the models with no drug effect were more than 25 times more likely than the alternative models given the data. We conclude that μ-opioid signalling is unlikely to underpin non-affiliative touch reward in humans.
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Affiliation(s)
- Guro E Løseth
- Department of Psychology, University of Oslo, Blindern, N Oslo, Norway
| | - Marie Eikemo
- Department of Psychology, University of Oslo, Blindern, N Oslo, Norway.,Department of Diagnostic Physics, Oslo University Hospital, Nydalen, N Oslo, Norway
| | - Siri Leknes
- Department of Psychology, University of Oslo, Blindern, N Oslo, Norway
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12
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Hammond T, Bombail V, Nielsen BL, Meddle SL, Lawrence AB, Brown SM. Relationships between play and responses to tickling in male juvenile rats. Appl Anim Behav Sci 2019. [DOI: 10.1016/j.applanim.2019.104879] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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13
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Fu Y, Depue RA. A novel neurobehavioral framework of the effects of positive early postnatal experience on incentive and consummatory reward sensitivity. Neurosci Biobehav Rev 2019; 107:615-640. [DOI: 10.1016/j.neubiorev.2019.09.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 09/08/2019] [Accepted: 09/17/2019] [Indexed: 12/22/2022]
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14
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Therapeutic efficacy of environmental enrichment for substance use disorders. Pharmacol Biochem Behav 2019; 188:172829. [PMID: 31778722 DOI: 10.1016/j.pbb.2019.172829] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 11/13/2019] [Accepted: 11/15/2019] [Indexed: 12/18/2022]
Abstract
Addiction to drug and alcohol is regarded as a major health problem worldwide for which available treatments show limited effectiveness. The biggest challenge remains to enhance the capacities of interventions to reduce craving, prevent relapse and promote long-term recovery. New strategies to meet these challenges are being explored. Findings from preclinical work suggest that environmental enrichment (EE) holds therapeutic potential for the treatment of substance use disorders, as demonstrated in a number of animal models of drug abuse. The EE intervention introduced after drug exposure leads to attenuation of compulsive drug taking, attenuation of the rewarding (and reinforcing) effects of drugs, reductions in control of behavior by drug cues, and, very importantly, relapse prevention. Clinical work also suggests that multidimensional EE interventions (involving physical activity, social interaction, vocational training, recreational and community involvement) might produce similar therapeutic effects, if implemented continuously and rigorously. In this review we survey preclinical and clinical studies assessing the efficacy of EE as a behavioral intervention for substance use disorders and address related challenges. We also review work providing empirical evidence for EE-induced neuroplasticity within the mesocorticolimbic system that is believed to contribute to the seemingly therapeutic effects of EE on drug and alcohol-related behaviors.
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15
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Lampe JF, Ruchti S, Burman O, Würbel H, Melotti L. Play like me: Similarity in playfulness promotes social play. PLoS One 2019; 14:e0224282. [PMID: 31648250 PMCID: PMC6812795 DOI: 10.1371/journal.pone.0224282] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 10/09/2019] [Indexed: 12/01/2022] Open
Abstract
Social play is associated with the experience of positive emotions in higher vertebrates and may be used as a measure of animal welfare. Altering motivation to play (e.g., through short-term social isolation) can temporarily affect play levels between familiar individuals, a process which may involve emotional contagion. This study investigated how forming groups based on known differences in the personality trait "playfulness" (i.e., the longer-term propensity of an individual to actively play from adolescence to early adulthood) affects social play. Seventy-six adolescent male Lister Hooded rats underwent a Play-in-Pairs test assessing their playfulness, ranked as high (H), intermediate (I) or low (L). At seven weeks of age, rats were resorted into homogenous groups of similar (LLL, III, HHH), or heterogeneous groups of dissimilar (HII, LII) playfulness. Social play was scored in the home cage at Weeks 8, 10, 12 of age. A second Play-in-Pairs test was performed (Week 11) to assess consistency of playfulness. A Social Preference test investigated whether I rats in heterogeneous groups preferred proximity with I, H or L cage mates. It was found that heterogeneous groups played less than homogeneous ones at adolescence (8 weeks of age), while play levels at early adulthood (Weeks 10 and 12) did not differ between groups. Play in the homogeneous groups decreased with age as expected, while it did not change over time in the heterogeneous groups, which did not compensate for the lower play levels shown at adolescence. Play-in-Pairs scores before and after resorting were mildly correlated, indicating some level of consistency over time despite the resorting procedure. In the Social Preference test, subjects did not prefer one playfulness level over another. We conclude that a mismatch in playfulness may negatively affect social play development, and thus the welfare, of rats. Groups made of animals with similar playfulness, even those initially scoring relatively low in this trait, seemed to be more successful in establishing play relationships during adolescence.
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Affiliation(s)
| | - Sabrina Ruchti
- Division of Animal Welfare, University of Bern, Bern, Switzerland
| | - Oliver Burman
- School of Life Sciences, University of Lincoln, Joseph Banks Laboratories, Lincoln, United Kingdom
| | - Hanno Würbel
- Division of Animal Welfare, University of Bern, Bern, Switzerland
| | - Luca Melotti
- Division of Animal Welfare, University of Bern, Bern, Switzerland
- Department of Behavioural Biology, University of Münster, Münster, Germany
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16
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Alugubelly N, Mohammad AN, Edelmann MJ, Nanduri B, Sayed M, Park JW, Carr RL. Proteomic and transcriptional profiling of rat amygdala following social play. Behav Brain Res 2019; 376:112210. [PMID: 31493430 DOI: 10.1016/j.bbr.2019.112210] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 09/03/2019] [Accepted: 09/03/2019] [Indexed: 12/31/2022]
Abstract
Social play is the most characteristic form of social interaction which is necessary for adolescents to develop proper cognitive, emotional, and social competency. The information available on neural substrates and the mechanism involved in social play is limited. This study characterized social play by proteomic and transcriptional profiling studies. Social play was performed on male Sprague Dawley rats on postnatal day 38 and protein and gene expression in the amygdala was determined following behavioral testing. The proteomic analysis led to the identification of 170 differentially expressed proteins (p ≤ 0.05) with 67 upregulated and 103 downregulated proteins. The transcriptomic analysis led to the identification of 188 genes (FDR ≤ 0.05) with 55 upregulated and 133 downregulated genes. DAVID analysis of gene/protein expression data revealed that social play altered GABAergic signaling, glutamatergic signaling, and G-protein coupled receptor (GPCR) signaling. These data suggest that the synaptic levels of GABA and glutamate increased during play. Ingenuity Pathway Analysis (IPA) confirmed these alterations. IPA also revealed that differentially expressed genes/proteins in our data had significant over representation of neurotransmitter signaling systems, including the opioid, serotonin, and dopamine systems, suggesting that play alters the systems involved in the regulation of reward. In addition, corticotropin-releasing hormone signaling was altered indicating that an increased level of stress occurs during play. Overall, our data suggest that increased inhibitory GPCR signaling in these neurotransmitter pathways occurs following social play as a physiological response to regulate the induced level of reward and stress and to maintain the excitatory-inhibitory balance in the neurotransmitter systems.
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Affiliation(s)
- Navatha Alugubelly
- Center for Environmental Health Sciences, MS, USA; Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - Afzaal N Mohammad
- Center for Environmental Health Sciences, MS, USA; Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - Mariola J Edelmann
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, USA
| | - Bindu Nanduri
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - Mohammed Sayed
- Department of Computer Engineering and Computer Science, KY, USA
| | - Juw Won Park
- Department of Computer Engineering and Computer Science, KY, USA; KBRIN Bioinformatics Core, University of Louisville, KY, USA.
| | - Russell L Carr
- Center for Environmental Health Sciences, MS, USA; Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA.
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17
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Schiavi S, Manduca A, Segatto M, Campolongo P, Pallottini V, Vanderschuren LJMJ, Trezza V. Unidirectional opioid-cannabinoid cross-tolerance in the modulation of social play behavior in rats. Psychopharmacology (Berl) 2019; 236:2557-2568. [PMID: 30903212 DOI: 10.1007/s00213-019-05226-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 03/10/2019] [Indexed: 01/04/2023]
Abstract
RATIONALE The endocannabinoid and the endogenous opioid systems interact in the modulation of social play behavior, a highly rewarding social activity abundantly expressed in young mammals. Prolonged exposure to opioid or cannabinoid receptor agonists induces cross-tolerance or cross-sensitization to their acute behavioral effects. OBJECTIVES AND METHODS Behavioral and biochemical experiments were performed to investigate whether cross-tolerance or cross-sensitization occurs to the play-enhancing effects of cannabinoid and opioid drugs on social play behavior, and the possible brain substrate involved. RESULTS The play-enhancing effects induced by systemic administration of JZL184, which inhibits the hydrolysis of the endocannabinoid 2-AG, were suppressed in animals repeatedly pretreated with the opioid receptor agonist morphine. Conversely, acute morphine administration increased social play in rats pretreated with vehicle or with either JZL184 or the cannabinoid agonist WIN55,212-2. Acute administration of JZL184 increased the activation of both CB1 receptors and their effector Akt in the nucleus accumbens and prefrontal cortex, brain regions important for the expression of social play. These effects were absent in animals pretreated with morphine. Furthermore, only animals repeatedly treated with morphine and acutely administered with JZL184 showed reduced activation of CB1 receptors and Akt in the amygdala. CONCLUSIONS The present study demonstrates a dynamic opioid-cannabinoid interaction in the modulation of social play behavior, occurring in limbic brain areas strongly implicated in social play behavior. A better understanding of opioid-cannabinoid interactions in social play contributes to clarify neurobiological aspects of social behavior at young age, which may provide new therapeutic targets for social dysfunctions.
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Affiliation(s)
- Sara Schiavi
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Viale G. Marconi 446, 00146, Rome, Italy
| | - Antonia Manduca
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Viale G. Marconi 446, 00146, Rome, Italy
| | - Marco Segatto
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Viale G. Marconi 446, 00146, Rome, Italy
| | - Patrizia Campolongo
- Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome, Rome, Italy
| | - Valentina Pallottini
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Viale G. Marconi 446, 00146, Rome, Italy
| | - Louk J M J Vanderschuren
- Department of Animals in Science and Society, Division of Behavioural Neuroscience, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Viviana Trezza
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Viale G. Marconi 446, 00146, Rome, Italy.
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18
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Perkins AE, Varlinskaya EI, Deak T. From adolescence to late aging: A comprehensive review of social behavior, alcohol, and neuroinflammation across the lifespan. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2019; 148:231-303. [PMID: 31733665 DOI: 10.1016/bs.irn.2019.08.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The passage of time dictates the pace at which humans and other organisms age but falls short of providing a complete portrait of how environmental, lifestyle and underlying biological processes contribute to senescence. Two fundamental features of the human experience that change dramatically across the lifespan include social interactions and, for many, patterns of alcohol consumption. Rodent models show great utility for understanding complex interactions among aging, social behavior and alcohol use and abuse, yet little is known about the neural changes in late aging that contribute to the natural decline in social behavior. Here, we posit that aging-related neuroinflammation contributes to the insipid loss of social motivation across the lifespan, an effect that is exacerbated by patterns of repeated alcohol consumption observed in many individuals. We provide a comprehensive review of (i) neural substrates crucial for the expression of social behavior under non-pathological conditions; (ii) unique developmental/lifespan vulnerabilities that may contribute to the divergent effects of low-and high-dose alcohol exposure; and (iii) aging-associated changes in neuroinflammation that may sit at the intersection between social processes and alcohol exposure. In doing so, we provide an overview of correspondence between lifespan/developmental periods between common rodent models and humans, give careful consideration to model systems used to aptly probe social behavior, identify points of coherence between human and animal models, and point toward a multitude of unresolved issues that should be addressed in future studies. Together, the combination of low-dose and high-dose alcohol effects serve to disrupt the normal development and maintenance of social relationships, which are critical for both healthy aging and quality of life across the lifespan. Thus, a more complete understanding of neural systems-including neuroinflammatory processes-which contribute to alcohol-induced changes in social behavior will provide novel opportunities and targets for promoting healthy aging.
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Affiliation(s)
- Amy E Perkins
- Developmental Exposure Alcohol Research Center, Behavioral Neuroscience Program, Department of Psychology, Binghamton University-SUNY, Binghamton, NY, United States
| | - Elena I Varlinskaya
- Developmental Exposure Alcohol Research Center, Behavioral Neuroscience Program, Department of Psychology, Binghamton University-SUNY, Binghamton, NY, United States
| | - Terrence Deak
- Developmental Exposure Alcohol Research Center, Behavioral Neuroscience Program, Department of Psychology, Binghamton University-SUNY, Binghamton, NY, United States.
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19
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Song TJ, Lan XY, Wei MP, Zhai FJ, Boeckers TM, Wang JN, Yuan S, Jin MY, Xie YF, Dang WW, Zhang C, Schön M, Song PW, Qiu MH, Song YY, Han SP, Han JS, Zhang R. Altered Behaviors and Impaired Synaptic Function in a Novel Rat Model With a Complete Shank3 Deletion. Front Cell Neurosci 2019; 13:111. [PMID: 30971895 PMCID: PMC6444209 DOI: 10.3389/fncel.2019.00111] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 03/06/2019] [Indexed: 11/24/2022] Open
Abstract
Mutations within the Shank3 gene, which encodes a key postsynaptic density (PSD) protein at glutamatergic synapses, contribute to the genetic etiology of defined autism spectrum disorders (ASDs), including Phelan-McDermid syndrome (PMS) and intellectual disabilities (ID). Although there are a series of genetic mouse models to study Shank3 gene in ASDs, there are few rat models with species-specific advantages. In this study, we established and characterized a novel rat model with a deletion spanning exons 11–21 of Shank3, leading to a complete loss of the major SHANK3 isoforms. Synaptic function and plasticity of Shank3-deficient rats were impaired detected by biochemical and electrophysiological analyses. Shank3-depleted rats showed impaired social memory but not impaired social interaction behaviors. In addition, impaired learning and memory, increased anxiety-like behavior, increased mechanical pain threshold and decreased thermal sensation were observed in Shank3-deficient rats. It is worth to note that Shank3-deficient rats had nearly normal levels of the endogenous social neurohormones oxytocin (OXT) and arginine-vasopressin (AVP). This new rat model will help to further investigate the etiology and assess potential therapeutic target and strategy for Shank3-related neurodevelopmental disorders.
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Affiliation(s)
- Tian-Jia Song
- Department of Neurobiology, School of Basic Medical Sciences, Peking University, Beijing, China.,Neuroscience Research Institute, Peking University, Beijing, China.,Key laboratory for Neuroscience, Ministry of Education/National Health and Family Planning Commission, Peking University, Beijing, China
| | - Xing-Yu Lan
- Department of Neurobiology, School of Basic Medical Sciences, Peking University, Beijing, China.,Neuroscience Research Institute, Peking University, Beijing, China.,Key laboratory for Neuroscience, Ministry of Education/National Health and Family Planning Commission, Peking University, Beijing, China
| | - Meng-Ping Wei
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University-IDG/McGovern Institute for Brain Research, Peking University, Beijing, China.,Department of Neurobiology, Capital Medical University, Beijing, China
| | - Fu-Jun Zhai
- Department of Neurobiology, School of Basic Medical Sciences, Peking University, Beijing, China.,Neuroscience Research Institute, Peking University, Beijing, China.,Key laboratory for Neuroscience, Ministry of Education/National Health and Family Planning Commission, Peking University, Beijing, China
| | - Tobias M Boeckers
- Institute for Anatomy and Cell Biology, Ulm University, Ulm, Germany
| | - Jia-Nan Wang
- Department of Neurobiology, School of Basic Medical Sciences, Peking University, Beijing, China.,Neuroscience Research Institute, Peking University, Beijing, China.,Key laboratory for Neuroscience, Ministry of Education/National Health and Family Planning Commission, Peking University, Beijing, China
| | - Shuo Yuan
- Department of Neurobiology, School of Basic Medical Sciences, Peking University, Beijing, China.,Neuroscience Research Institute, Peking University, Beijing, China.,Key laboratory for Neuroscience, Ministry of Education/National Health and Family Planning Commission, Peking University, Beijing, China
| | - Meng-Ying Jin
- Department of Neurobiology, School of Basic Medical Sciences, Peking University, Beijing, China.,Neuroscience Research Institute, Peking University, Beijing, China.,Key laboratory for Neuroscience, Ministry of Education/National Health and Family Planning Commission, Peking University, Beijing, China
| | - Yu-Fei Xie
- Department of Neurobiology, School of Basic Medical Sciences, Peking University, Beijing, China.,Neuroscience Research Institute, Peking University, Beijing, China.,Key laboratory for Neuroscience, Ministry of Education/National Health and Family Planning Commission, Peking University, Beijing, China
| | - Wan-Wen Dang
- Department of Neurobiology, School of Basic Medical Sciences, Peking University, Beijing, China.,Neuroscience Research Institute, Peking University, Beijing, China.,Key laboratory for Neuroscience, Ministry of Education/National Health and Family Planning Commission, Peking University, Beijing, China
| | - Chen Zhang
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University-IDG/McGovern Institute for Brain Research, Peking University, Beijing, China.,Department of Neurobiology, Capital Medical University, Beijing, China
| | - Michael Schön
- Institute for Anatomy and Cell Biology, Ulm University, Ulm, Germany
| | - Pei-Wen Song
- Department of Neurobiology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Mei-Hong Qiu
- Department of Neurobiology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Ya-Yue Song
- School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Song-Ping Han
- Wuxi HANS Health Medical Technology Co., Ltd., Wuxi, China
| | - Ji-Sheng Han
- Department of Neurobiology, School of Basic Medical Sciences, Peking University, Beijing, China.,Neuroscience Research Institute, Peking University, Beijing, China.,Key laboratory for Neuroscience, Ministry of Education/National Health and Family Planning Commission, Peking University, Beijing, China
| | - Rong Zhang
- Department of Neurobiology, School of Basic Medical Sciences, Peking University, Beijing, China.,Neuroscience Research Institute, Peking University, Beijing, China.,Key laboratory for Neuroscience, Ministry of Education/National Health and Family Planning Commission, Peking University, Beijing, China
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20
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Matthews GA, Tye KM. Neural mechanisms of social homeostasis. Ann N Y Acad Sci 2019; 1457:5-25. [PMID: 30875095 DOI: 10.1111/nyas.14016] [Citation(s) in RCA: 98] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 12/15/2018] [Accepted: 01/09/2019] [Indexed: 12/21/2022]
Abstract
Social connections are vital to survival throughout the animal kingdom and are dynamic across the life span. There are debilitating consequences of social isolation and loneliness, and social support is increasingly a primary consideration in health care, disease prevention, and recovery. Considering social connection as an "innate need," it is hypothesized that evolutionarily conserved neural systems underlie the maintenance of social connections: alerting the individual to their absence and coordinating effector mechanisms to restore social contact. This is reminiscent of a homeostatic system designed to maintain social connection. Here, we explore the identity of neural systems regulating "social homeostasis." We review findings from rodent studies evaluating the rapid response to social deficit (in the form of acute social isolation) and propose that parallel, overlapping circuits are engaged to adapt to the vulnerabilities of isolation and restore social connection. By considering the neural systems regulating other homeostatic needs, such as energy and fluid balance, we discuss the potential attributes of social homeostatic circuitry. We reason that uncovering the identity of these circuits/mechanisms will facilitate our understanding of how loneliness perpetuates long-term disease states, which we speculate may result from sustained recruitment of social homeostatic circuits.
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Affiliation(s)
- Gillian A Matthews
- Department of Brain and Cognitive Sciences, The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Kay M Tye
- Department of Brain and Cognitive Sciences, The Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, Massachusetts.,The Salk Institute for Biological Sciences, La Jolla, California
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21
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A Review of Welfare Assessment Methods in Reptiles, and Preliminary Application of the Welfare Quality ® Protocol to the Pygmy Blue-Tongue Skink, Tiliqua adelaidensis, Using Animal-Based Measures. Animals (Basel) 2019; 9:ani9010027. [PMID: 30658490 PMCID: PMC6356264 DOI: 10.3390/ani9010027] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Revised: 01/02/2019] [Accepted: 01/12/2019] [Indexed: 12/18/2022] Open
Abstract
Reptiles are held at wildlife parks and zoos for display and conservation breeding programs and are increasingly being kept as pets. Reliable indicators of welfare for reptiles need to be identified. Current guidelines for the captive management of reptiles utilize resource-based, rather than animal-based indicators; the latter being a more direct reflection of affective state. In this paper we review the literature on welfare assessment methods in reptiles with a focus on animal-based measures. We conclude that, whilst a number of physiological and behavioral indicators of welfare have been applied in reptiles, there is need for further validation of these methods across the diversity of species within the Class. Methods of positive welfare state assessment are comparatively understudied and need elucidation. Finally, we examine some widely-used welfare assessment tools in mammals and explore the application of the Welfare Quality® Protocol to the endangered pygmy blue-tongue skink, Tiliqua adelaidensis. We propose that this framework can form the basis for the development of taxon-specific tools with consideration of species-specific biology.
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22
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Supekar K, Kochalka J, Schaer M, Wakeman H, Qin S, Padmanabhan A, Menon V. Deficits in mesolimbic reward pathway underlie social interaction impairments in children with autism. Brain 2018; 141:2795-2805. [PMID: 30016410 PMCID: PMC6113649 DOI: 10.1093/brain/awy191] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 05/23/2018] [Accepted: 06/28/2018] [Indexed: 12/19/2022] Open
Abstract
Lack of interest in social interaction is a hallmark of autism spectrum disorder. Animal studies have implicated the mesolimbic reward pathway in driving and reinforcing social behaviour, but little is known about the integrity of this pathway and its behavioural consequences in children with autism spectrum disorder. Here we test the hypothesis that the structural and functional integrity of the mesolimbic reward pathway is aberrant in children with autism spectrum disorder, and these aberrancies contribute to the social interaction impairments. We examine structural and functional connectivity of the mesolimbic reward pathway in two independent cohorts totalling 82 children aged 7-13 years with autism spectrum disorder and age-, gender-, and intelligence quotient-matched typically developing children (primary cohort: children with autism spectrum disorder n = 24, typically developing children n = 24; replication cohort: children with autism spectrum disorder n = 17, typically developing children n = 17), using high angular resolution diffusion-weighted imaging and functional MRI data. We reliably identify white matter tracts linking-the nucleus accumbens and the ventral tegmental area-key subcortical nodes of the mesolimbic reward pathway, and provide reproducible evidence for structural aberrations in these tracts in children with autism spectrum disorder. Further, we show that structural aberrations are accompanied by aberrant functional interactions between nucleus accumbens and ventral tegmental area in response to social stimuli. Crucially, we demonstrate that both structural and functional circuit aberrations in the mesolimbic reward pathway are related to parent-report measures of social interaction impairments in affected children. Our findings, replicated across two independent cohorts, reveal that deficits in the mesolimbic reward pathway contribute to impaired social skills in childhood autism, and provide fundamental insights into neurobiological mechanisms underlying reduced social interest in humans.
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Affiliation(s)
- Kaustubh Supekar
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
| | - John Kochalka
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
| | - Marie Schaer
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- Department of Psychiatry, University of Geneva, Geneva, Switzerland
| | - Holly Wakeman
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
| | - Shaozheng Qin
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Faculty of Psychology at Beijing Normal University, Beijing, China
| | - Aarthi Padmanabhan
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
| | - Vinod Menon
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA
- Stanford Neurosciences Institute, Stanford University, Stanford, CA, USA
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23
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Wood A, Niedenthal P. Developing a social functional account of laughter. SOCIAL AND PERSONALITY PSYCHOLOGY COMPASS 2018. [DOI: 10.1111/spc3.12383] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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24
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Riters LV, Spool JA, Merullo DP, Hahn AH. Song practice as a rewarding form of play in songbirds. Behav Processes 2017; 163:91-98. [PMID: 29031813 DOI: 10.1016/j.beproc.2017.10.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 09/15/2017] [Accepted: 10/05/2017] [Indexed: 12/14/2022]
Abstract
In adult songbirds, the primary functions of song are mate attraction and territory defense; yet, many songbirds sing at high rates as juveniles and outside these primary contexts as adults. Singing outside primary contexts is critical for song learning and maintenance, and ultimately necessary for breeding success. However, this type of singing (i.e., song "practice") occurs even in the absence of immediate or obvious extrinsic reinforcement; that is, it does not attract mates or repel competitors. Here we review studies that support the hypothesis that song practice is stimulated and maintained by intrinsic reward mechanisms (i.e., that it is associated with a positive affective state). Additionally, we propose that song practice can be considered a rewarding form of play behavior similar to forms of play observed in multiple young animals as they practice sequences of motor events that are used later in primary adult reproductive contexts. This review highlights research suggesting at least partially overlapping roles for neural reward systems in birdsong and mammalian play and evidence that steroid hormones modify these systems to shift animals from periods of intrinsically rewarded motor exploration (i.e., singing in birds and play in mammals) to the use of similar motor patterns in primary reproductive contexts.
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Affiliation(s)
- Lauren V Riters
- Department of Integrative Biology, University of Wisconsin-Madison, 428 Birge Hall, 430 Lincoln Drive, Madison, WI 53706, United States.
| | - Jeremy A Spool
- Department of Integrative Biology, University of Wisconsin-Madison, 428 Birge Hall, 430 Lincoln Drive, Madison, WI 53706, United States.
| | - Devin P Merullo
- Department of Integrative Biology, University of Wisconsin-Madison, 428 Birge Hall, 430 Lincoln Drive, Madison, WI 53706, United States.
| | - Allison H Hahn
- Department of Integrative Biology, University of Wisconsin-Madison, 428 Birge Hall, 430 Lincoln Drive, Madison, WI 53706, United States.
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25
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Bershad AK, Ruiz NA, de Wit H. Effects of Buprenorphine on Responses to Emotional Stimuli in Individuals with a Range of Mood Symptomatology. Int J Neuropsychopharmacol 2017; 21:120-127. [PMID: 29025085 PMCID: PMC5793829 DOI: 10.1093/ijnp/pyx077] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 08/31/2017] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND The opioid drug buprenorphine has been shown to modify responses to emotional stimuli and may have antidepressant properties. In preclinical studies, it shows antidepressant-like and anxiolytic-like effects, and a handful of clinical studies suggest it may reduce symptoms of depression in patients. We have shown that low doses of buprenorphine reduce responses to negative emotional stimuli in healthy adults. Here we extended these findings to individuals with symptoms of depression and anxiety. METHODS We examined the effects of buprenorphine on attention to emotional facial expressions and ratings of and psychophysiological responses to emotional images in adults with a range of mood symptomatology. Volunteers (n=38) were recruited with low, mild, moderate, and severe scores on the Depression-Anxiety-Stress Scale. They attended 2 laboratory sessions during which they received either placebo or 0.2 mg sublingual buprenorphine in randomized order under double-blind conditions. During peak drug effect, participants completed a visual attention task assessing responses to emotional faces and a picture-rating task assessing responses to emotional images with and without social content. RESULTS Buprenorphine reduced attention to fearful facial expressions as it did in our previous study, and the emotion-specific effect was especially pronounced in individuals with high Depression-Anxiety-Stress Scale scores. The drug also increased ratings of positivity of images with social content, but this effect was less strong in individuals with higher Depression-Anxiety-Stress Scale scores. CONCLUSIONS These results suggest low doses of buprenorphine may reduce some dimensions of responses to negative emotional stimuli in individuals high on depression or anxiety, while leaving other dimensions unaffected.
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Affiliation(s)
- Anya K Bershad
- Department of Psychiatry and Behavioral Neuroscience, Chicago, Illinois,University of Chicago Interdisciplinary Scientist Training Program, Chicago, Illinois,University of Chicago, Chicago, Illinois
| | - Nicholas A Ruiz
- Department of Psychiatry and Behavioral Neuroscience, Chicago, Illinois
| | - Harriet de Wit
- Department of Psychiatry and Behavioral Neuroscience, Chicago, Illinois,Correspondence: Harriet de Wit, PhD, Department of Psychiatry and Behavioral Neuroscience, University of Chicago, 5841 S. Maryland Ave., MC3077, Chicago, IL 60637 ()
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26
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Pellissier LP, Gandía J, Laboute T, Becker JAJ, Le Merrer J. μ opioid receptor, social behaviour and autism spectrum disorder: reward matters. Br J Pharmacol 2017; 175:2750-2769. [PMID: 28369738 DOI: 10.1111/bph.13808] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 03/10/2017] [Accepted: 03/24/2017] [Indexed: 12/19/2022] Open
Abstract
The endogenous opioid system is well known to relieve pain and underpin the rewarding properties of most drugs of abuse. Among opioid receptors, the μ receptor mediates most of the analgesic and rewarding properties of opioids. Based on striking similarities between social distress, physical pain and opiate withdrawal, μ receptors have been proposed to play a critical role in modulating social behaviour in humans and animals. This review summarizes experimental data demonstrating such role and proposes a novel model, the μ opioid receptor balance model, to account for the contribution of μ receptors to the subtle regulation of social behaviour. Interestingly, μ receptor null mice show behavioural deficits similar to those observed in patients with autism spectrum disorder (ASD), including severe impairment in social interactions. Therefore, after a brief summary of recent evidence for blunted (social) reward processes in subjects with ASD, we review here arguments for altered μ receptor function in this pathology. This article is part of a themed section on Emerging Areas of Opioid Pharmacology. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.14/issuetoc.
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Affiliation(s)
- Lucie P Pellissier
- Physiologie de la Reproduction et des Comportements, INRA UMR-0085, CNRS UMR-7247, Université de Tours Rabelais, IFCE, Inserm, Nouzilly, France
| | - Jorge Gandía
- Physiologie de la Reproduction et des Comportements, INRA UMR-0085, CNRS UMR-7247, Université de Tours Rabelais, IFCE, Inserm, Nouzilly, France
| | - Thibaut Laboute
- Physiologie de la Reproduction et des Comportements, INRA UMR-0085, CNRS UMR-7247, Université de Tours Rabelais, IFCE, Inserm, Nouzilly, France
| | - Jérôme A J Becker
- Physiologie de la Reproduction et des Comportements, INRA UMR-0085, CNRS UMR-7247, Université de Tours Rabelais, IFCE, Inserm, Nouzilly, France
| | - Julie Le Merrer
- Physiologie de la Reproduction et des Comportements, INRA UMR-0085, CNRS UMR-7247, Université de Tours Rabelais, IFCE, Inserm, Nouzilly, France
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Lampe JF, Burman O, Würbel H, Melotti L. Context-dependent individual differences in playfulness in male rats. Dev Psychobiol 2017; 59:460-472. [PMID: 28247407 DOI: 10.1002/dev.21509] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 01/19/2017] [Accepted: 02/03/2017] [Indexed: 11/11/2022]
Abstract
Play has been proposed as an indicator of positive emotions and welfare in higher vertebrates. This study investigated playfulness in male rats by exploring its consistency across motivational states (with/without prior short social isolation) and two age points at early and late adolescence. Twenty-four male Lister Hooded rats housed in cages of four underwent two play tests: conspecific Play-in-Pairs and Tickling by the experimenter, which were compared with play in the home cage and basal anxiety levels. Play-in-Pairs measures were consistent across age and motivational states, and were independent from anxiety. Positively valenced vocalizations in the Tickling test were also consistent across age, yet were negatively related to anxiety. Play-in-Pairs and Tickling play contexts, as well as social and solitary play types, were unrelated. Therefore, this study supports the existence of consistent individual differences in playfulness in rats, and suggests that different play contexts and types represent motivationally distinct systems.
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Affiliation(s)
- Jessica F Lampe
- Division of Animal Welfare, University of Bern, Bern, Switzerland
| | - Oliver Burman
- Joseph Banks Laboratories, School of Life Sciences, University of Lincoln, Lincoln, UK
| | - Hanno Würbel
- Division of Animal Welfare, University of Bern, Bern, Switzerland
| | - Luca Melotti
- Division of Animal Welfare, University of Bern, Bern, Switzerland
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Manduca A, Lassalle O, Sepers M, Campolongo P, Cuomo V, Marsicano G, Kieffer B, Vanderschuren LJMJ, Trezza V, Manzoni OJJ. Interacting Cannabinoid and Opioid Receptors in the Nucleus Accumbens Core Control Adolescent Social Play. Front Behav Neurosci 2016; 10:211. [PMID: 27899885 PMCID: PMC5110529 DOI: 10.3389/fnbeh.2016.00211] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 10/18/2016] [Indexed: 12/31/2022] Open
Abstract
Social play behavior is a highly rewarding, developmentally important form of social interaction in young mammals. However, its neurobiological underpinnings remain incompletely understood. Previous work has suggested that opioid and endocannabinoid neurotransmission interact in the modulation of social play. Therefore, we combined behavioral, pharmacological, electrophysiological, and genetic approaches to elucidate the role of the endocannabinoid 2-arachidonoylglycerol (2-AG) in social play, and how cannabinoid and opioid neurotransmission interact to control social behavior in adolescent rodents. Systemic administration of the 2-AG hydrolysis inhibitor JZL184 or the opioid receptor agonist morphine increased social play behavior in adolescent rats. These effects were blocked by systemic pretreatment with either CB1 cannabinoid receptor (CB1R) or mu-opioid receptor (MOR) antagonists. The social play-enhancing effects of systemic morphine or JZL184 treatment were also prevented by direct infusion of the CB1R antagonist SR141716 and the MOR antagonist naloxone into the nucleus accumbens core (NAcC). Searching for synaptic correlates of these effects in adolescent NAcC excitatory synapses, we observed that CB1R antagonism blocked the effect of the MOR agonist DAMGO and, conversely, that naloxone reduced the effect of a cannabinoid agonist. These results were recapitulated in mice, and completely abolished in CB1R and MOR knockout mice, suggesting that the functional interaction between CB1R and MOR in the NAcC in the modulation of social behavior is widespread in rodents. The data shed new light on the mechanism by which endocannabinoid lipids and opioid peptides interact to orchestrate rodent socioemotional behaviors.
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Affiliation(s)
- Antonia Manduca
- Institut National De La Santé Et De La Recherche Médicale U901Marseille, France; Université de la Méditerranée UMR S901 Aix-Marseille 2Marseille, France; INMEDMarseille, France
| | - Olivier Lassalle
- Institut National De La Santé Et De La Recherche Médicale U901Marseille, France; Université de la Méditerranée UMR S901 Aix-Marseille 2Marseille, France; INMEDMarseille, France
| | - Marja Sepers
- Institut National De La Santé Et De La Recherche Médicale U901Marseille, France; Université de la Méditerranée UMR S901 Aix-Marseille 2Marseille, France; INMEDMarseille, France
| | - Patrizia Campolongo
- Department of Physiology and Pharmacology, Sapienza University of Rome Rome, Italy
| | - Vincenzo Cuomo
- Department of Physiology and Pharmacology, Sapienza University of Rome Rome, Italy
| | - Giovanni Marsicano
- NeuroCentre Magendie, Endocannabinoids and Neuroadaptation, Institut National De La Santé Et De La Recherche Médicale U862Bordeaux, France; NeuroCentre Magendie U862, University of BordeauxBordeaux, France
| | - Brigitte Kieffer
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Centre National de la Recherche Scientifique/Institut National de la Santé et de la Recherche Médicale/Université de Strasbourg Illkirch, France
| | - Louk J M J Vanderschuren
- Division of Behavioural Neuroscience, Department of Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University Utrecht, Netherlands
| | - Viviana Trezza
- Section of Biomedical Sciences and Technologies, Department of Science, University Roma Tre Rome, Italy
| | - Olivier J J Manzoni
- Institut National De La Santé Et De La Recherche Médicale U901Marseille, France; Université de la Méditerranée UMR S901 Aix-Marseille 2Marseille, France; INMEDMarseille, France
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Vanderschuren LJMJ, Achterberg EJM, Trezza V. The neurobiology of social play and its rewarding value in rats. Neurosci Biobehav Rev 2016; 70:86-105. [PMID: 27587003 DOI: 10.1016/j.neubiorev.2016.07.025] [Citation(s) in RCA: 196] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Revised: 07/18/2016] [Accepted: 07/21/2016] [Indexed: 02/07/2023]
Abstract
In the young of many mammalian species, including humans, a vigorous and highly rewarding social activity is abundantly expressed, known as social play behaviour. Social play is thought to be important for the development of social, cognitive and emotional processes and their neural underpinnings, and it is disrupted in pediatric psychiatric disorders. Here, we summarize recent progress in our understanding of the brain mechanisms of social play behaviour, with a focus on its rewarding properties. Opioid, endocannabinoid, dopamine and noradrenaline systems play a prominent role in the modulation of social play. Of these, dopamine is particularly important for the motivational properties of social play. The nucleus accumbens has been identified as a key site for opioid and dopamine modulation of social play. Endocannabinoid influences on social play rely on the basolateral amygdala, whereas noradrenaline modulates social play through the basolateral amygdala, habenula and prefrontal cortex. In sum, social play behaviour is the result of coordinated activity in a network of corticolimbic structures, and its monoamine, opioid and endocannabinoid innervation.
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Affiliation(s)
- Louk J M J Vanderschuren
- Department of Animals in Science and Society, Division of Behavioural Neuroscience, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
| | - E J Marijke Achterberg
- Department of Animals in Science and Society, Division of Behavioural Neuroscience, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Viviana Trezza
- Department of Science, Section of Biomedical Sciences and Technologies, University "Roma Tre", Rome, Italy
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Dopaminergic Neurotransmission in the Nucleus Accumbens Modulates Social Play Behavior in Rats. Neuropsychopharmacology 2016; 41:2215-23. [PMID: 26860202 PMCID: PMC4946055 DOI: 10.1038/npp.2016.22] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 01/25/2016] [Accepted: 02/04/2016] [Indexed: 12/21/2022]
Abstract
Social play behavior is a highly rewarding form of social interaction displayed by young mammals. Social play is important for neurobehavioral development and it has been found to be impaired in several developmental psychiatric disorders. In line with the rewarding properties of social play, we have previously identified the nucleus accumbens (NAc) as an important site of action for endocannabinoid and opioid modulation of this behavior. NAc dopamine has a well-known role in certain components of reward processes, such as incentive motivation. However, its contribution to the positive emotional aspects of social interactions is less clear. Therefore, we investigated the role of dopaminergic neurotransmission in the NAc in social play behavior in rats. We found that intra-NAc infusion of the dopamine releaser/reuptake inhibitor amphetamine increased social play behavior that was dependent on activation of both D1 and D2 dopamine receptors. This increase in social play behavior was mimicked by intra-NAc infusion of the dopamine receptor agonist apomorphine, but not of the dopamine reuptake inhibitor GBR-12909. Blockade of either D1 or D2 NAc dopamine receptors reduced social play in animals highly motivated to play as a result of longer social isolation before testing. Last, blockade of NAc dopamine receptors prevented the play-enhancing effects of endocannabinoid and opioid receptor stimulation. These findings demonstrate an important modulatory role of NAc dopaminergic neurotransmission in social play. Thus, functional activity in the mesolimbic dopamine pathway plays an important role in adaptive social development, whereas abnormal NAc dopamine function may underlie the social impairments observed in developmental psychiatric disorders such as autism, attention deficit hyperactivity disorder or early-onset schizophrenia.
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Abstract
Play is an important part of normal childhood development and is seen in varied forms among many mammals. While not indispensable to normal development, playful social experiences as juveniles may provide an opportunity to develop flexible behavioral strategies when novel and uncertain situations arise as an adult. To understand the neurobiological mechanisms responsible for play and how the functions of play may relate to these neural substrates, the rat has become the model of choice. Play in the rat is easily quantified, tightly regulated, and can be modulated by genetic factors and postnatal experiences. Brain areas most likely to be involved in the modulation of play include regions within the prefrontal cortex, dorsal and ventral striatum, some regions of the amygdala, and habenula. This paper discusses what we currently know about the neurobiological substrates of play and how this can help illuminate functional questions about the putative benefits of play.
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Affiliation(s)
- Stephen M Siviy
- Department of Psychology, Gettysburg College, Gettysburg, PA 17325, USA
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Granholm L, Roman E, Nylander I. Single housing during early adolescence causes time-, area- and peptide-specific alterations in endogenous opioids of rat brain. Br J Pharmacol 2015; 172:606-14. [PMID: 24821004 PMCID: PMC4292972 DOI: 10.1111/bph.12753] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2013] [Revised: 03/06/2014] [Accepted: 04/23/2014] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND AND PURPOSE A number of experimental procedures require single housing to assess individual behaviour and physiological responses to pharmacological treatments. The endogenous opioids are closely linked to social interaction, especially early in life, and disturbance in the social environment may affect opioid peptides and thereby confound experimental outcome. The aim of the present study was to examine time-dependent effects of single housing on opioid peptides in rats. EXPERIMENTAL APPROACH Early adolescent Sprague Dawley rats (post-natal day 22) were subjected to either prolonged (7 days) or short (30 min) single housing. Several brain regions were dissected and immunoreactive levels of Met-enkephalin-Arg(6) Phe(7) (MEAP), dynorphin B and nociception/orphanin FQ, as well as serum corticosterone were measured using RIA. KEY RESULTS Prolonged single housing reduced immunoreactive MEAP in hypothalamus, cortical regions, amygdala, substantia nigra and periaqueductal grey. Short single housing resulted in an acute stress response as indicated by high levels of corticosterone, accompanied by elevated immunoreactive nociceptin/orphanin FQ in medial prefrontal cortex, nucleus accumbens and amygdala. Neither short nor prolonged single housing affected dynorphin B. CONCLUSIONS AND IMPLICATIONS Disruption in social environmental conditions of rats, through single housing during early adolescence, resulted in time-, area- and peptide-specific alterations in endogenous opioids in the brain. These results provide further evidence for an association between early life social environment and opioids. Furthermore, the results have implications for experimental design; in any pharmacological study involving opioid peptides, it is important to distinguish between effects induced by housing and treatment. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.
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Affiliation(s)
- L Granholm
- Department of Pharmaceutical Biosciences, Neuropharmacology, Addiction and Behaviour, Uppsala University, Uppsala, Sweden
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Loseth GE, Ellingsen DM, Leknes S. State-dependent μ-opioid modulation of social motivation. Front Behav Neurosci 2014; 8:430. [PMID: 25565999 PMCID: PMC4264475 DOI: 10.3389/fnbeh.2014.00430] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 11/25/2014] [Indexed: 12/02/2022] Open
Abstract
Social mammals engage in affiliative interactions both when seeking relief from negative affect and when searching for pleasure and joy. These two motivational states are both modulated by μ-opioid transmission. The μ-opioid receptor (MOR) system in the brain mediates pain relief and reward behaviors, and is implicated in social reward processing and affiliative bonding across mammalian species. However, pharmacological manipulation of the μ-opioid system has yielded opposite effects on rodents and primates: in rodents, social motivation is generally increased by MOR agonists and reduced by antagonists, whereas the opposite pattern has been shown in primates. Here, we address this paradox by taking into account differences in motivational state. We first review evidence for μ-opioid mediation of reward processing, emotion regulation, and affiliation in humans, non-human primates, rodents and other species. Based on the consistent cross-species similarities in opioid functioning, we propose a unified, state-dependent model for μ-opioid modulation of affiliation across the mammalian species. Finally, we show that this state-dependent model is supported by evidence from both rodent and primate studies, when species and age differences in social separation response are taken into account.
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Affiliation(s)
- Guro E. Loseth
- Department of Psychology, University of OsloOslo, Norway
| | | | - Siri Leknes
- Department of Psychology, University of OsloOslo, Norway
- The Intervention Centre, Oslo University HospitalOslo, Norway
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Himmler BT, Pellis SM, Kolb B. Juvenile play experience primes neurons in the medial prefrontal cortex to be more responsive to later experiences. Neurosci Lett 2013; 556:42-5. [PMID: 24103373 DOI: 10.1016/j.neulet.2013.09.061] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2013] [Revised: 09/24/2013] [Accepted: 09/26/2013] [Indexed: 01/17/2023]
Abstract
Juvenile play behavior in rats promotes later behavioral flexibility and appears to do so by modifying the neural systems that regulate the animal's response to unexpected challenges. For example, the experience of play has been shown to prune the dendritic arbor of the cells in the medial prefrontal cortex (mPFC), part of the brain's executive control system. The objective of the present study was to determine if the play-induced changes in the mPFC promotes greater plasticity to experiences later in life. In order to test this possibility, exposure to nicotine was used as the secondary experience given later in life, as it has been shown to produce later changes to the morphology of mPFC pyramidal neurons. Animals were either paired with three same-sex peers (play condition) or one adult (no play condition) during their juvenile period. As young adults, half of the rats from each condition were exposed to repeated injections of nicotine and the other half to injections of saline. The neural plasticity of the mPFC was measured by changes in length and branching of dendrites. Neural changes induced separately by play and by nicotine were consistent with previously published findings. The novel finding was that the cells in the mPFC exhibit a greater response to exposure to nicotine if the rats first had play experience. These findings suggest that juvenile play experiences enhance the plasticity of some neural systems.
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Affiliation(s)
- B T Himmler
- Department of Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada.
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Wöhr M, Schwarting RKW. Affective communication in rodents: ultrasonic vocalizations as a tool for research on emotion and motivation. Cell Tissue Res 2013; 354:81-97. [DOI: 10.1007/s00441-013-1607-9] [Citation(s) in RCA: 200] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2013] [Accepted: 02/28/2013] [Indexed: 10/27/2022]
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D'Amato FR, Pavone F. Modulation of nociception by social factors in rodents: contribution of the opioid system. Psychopharmacology (Berl) 2012; 224:189-200. [PMID: 22993049 DOI: 10.1007/s00213-012-2863-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 09/01/2012] [Indexed: 12/30/2022]
Abstract
RATIONALE The opioid system is involved in the regulation of several behavioral and physiological responses, controlling pain, reward, and addictive behaviors. Opioid administration, depending on drugs and doses, usually affects sociability reducing interactions between conspecifics, whereas some affiliative behaviors such as sexual activity, social grooming, and play behavior increase the endogenous opioid activity. OBJECTIVES The possible interaction between endogenous opioids released during socio/sexual behavior and their analgesic effect on pain response is reviewed in the rodent literature. RESULTS Direct evidence for socially mediated opioid changes resulting in increase in nociceptive threshold derives from studies exploring the effects of defeat experiences, social isolation, maternal, sexual behavior, and social reunion among kin or familiar animals in laboratory rodents. Indirect evidence for endogenous activation of the opioid system, possibly affecting pain sensitivity, derives from studies investigating the relevance of natural social reward using the conditioned place preference protocols or analyzing ultrasonic vocalizations associated to positive affective contexts. Finally, genetic and epigenetic factors that affect the opioid system during development are reported to be involved in modulating the response to social stimuli as well as nociception. CONCLUSIONS All studies highlight the relevance of affiliative contact behavior between conspecifics that is responsible for the activation of the endogenous mu-opioid system, inducing nociceptive threshold increase.
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Affiliation(s)
- Francesca R D'Amato
- Cell Biology and Neurobiology Institute, National Research Council, Via del Fosso di Fiorano 64, 00143 Rome, Italy.
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Social influences on morphine-conditioned place preference in adolescent BALB/cJ and C57BL/6J mice. Psychopharmacology (Berl) 2012; 219:923-32. [PMID: 21837434 PMCID: PMC3638792 DOI: 10.1007/s00213-011-2421-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Accepted: 07/15/2011] [Indexed: 01/21/2023]
Abstract
RATIONALE Among human adolescents, drug use is substantially influenced by the attitudes and behaviors of peers. Social factors also affect the drug-seeking behaviors of laboratory animals. Conditioned place preference (CPP) experiments indicate that social context can influence the degree to which rodents derive a rewarding experience from drugs of abuse. However, the precise manner by which social factors alter drug reward in adolescent rodents remains unknown. OBJECTIVES We employed the relatively asocial BALB/cJ (BALB) mouse strain and the more prosocial C57BL/6J (B6) strain to explore whether "low" or "high" motivation to be with peers influences the effects of social context on morphine CPP (MCPP). METHODS Adolescent mice were conditioned by subcutaneous injections of morphine sulfate (0.25, 1.0, or 5.0 mg/kg). During the MCPP procedure, mice were housed in either isolation (Ih) or within a social group (Sh). Similarly, following injection, mice were conditioned either alone (Ic) or within a social group (Sc). RESULTS Adolescent B6 mice expressed a robust MCPP response except when subjected to Ih-Sc, which indicates that, following isolation, mice with high levels of social motivation are less susceptible to the rewarding properties of morphine when they are conditioned in a social group. By contrast, MCPP responses of BALB mice were most sensitive to morphine conditioning when subjects experienced a change in their social environment between housing and conditioning (Ih-Sc or Sh-Ic). CONCLUSIONS Our findings demonstrate that susceptibility to morphine-induced reward in adolescent mice is moderated by a complex interaction between social context and heritable differences in social motivation.
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Siviy SM, Panksepp J. In search of the neurobiological substrates for social playfulness in mammalian brains. Neurosci Biobehav Rev 2011; 35:1821-30. [DOI: 10.1016/j.neubiorev.2011.03.006] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Revised: 03/06/2011] [Accepted: 03/07/2011] [Indexed: 01/04/2023]
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Siviy SM, Deron LM, Kasten CR. Serotonin, motivation, and playfulness in the juvenile rat. Dev Cogn Neurosci 2011; 1:606-16. [PMID: 22436572 DOI: 10.1016/j.dcn.2011.07.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Revised: 06/27/2011] [Accepted: 07/03/2011] [Indexed: 11/30/2022] Open
Abstract
The effects of the selective 5HT(1A) agonist 8-OH-DPAT were assessed on the play behavior of juvenile rats. When both rats of the test pair were comparably motivated to play, the only significant effect of 8-OH-DPAT was for play to be reduced at higher doses. When there was a baseline asymmetry in playful solicitation due to a differential motivation to play and only one rat of the pair was treated, low doses of 8-OH-DPAT resulted in a collapse of asymmetry in playful solicitations. It did not matter whether the rat that was treated initially accounted for more nape contacts or fewer nape contacts, the net effect of 8-OH-DPAT in this model was for low doses of 8-OH-DPAT to decrease a pre-established asymmetry in play solicitation. It is concluded that selective stimulation of 5HT(1A) receptors changes the dynamic of a playful interaction between two participants that are differentially motivated to play. These results are discussed within a broader framework of serotonergic involvement in mammalian playfulness.
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Affiliation(s)
- Stephen M Siviy
- Department of Psychology, Gettysburg College, Gettysburg, PA 17325, USA.
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Age-dependent and strain-dependent influences of morphine on mouse social investigation behavior. Behav Pharmacol 2011; 22:147-59. [PMID: 21358324 DOI: 10.1097/fbp.0b013e328343d7dd] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Opioid-coded neural circuits play a substantial role in how individuals respond to drugs of abuse. Most individuals begin using such drugs during adolescence and within a social context. Several studies indicate that adolescent mice exhibit a heightened sensitivity to the effects of morphine, a prototypical opiate drug, but it is unclear whether these developmental differences are related to aspects of motivated behavior. Moreover, exposure to opioids within the rodent brain can alter the expression of social behavior, yet little is known about whether this relationship changes as a function of development or genetic variation. In this study, we conducted a series of experiments to characterize the relationship between genetic background, adolescent development and morphine-induced changes in mouse social investigation (SI). At two time points during adolescent development [postnatal days (PD) 25 and 45], social interactions of test mice of the gregarious C57BL/6J (B6) strain were more tolerant to the suppressive effects of morphine [effective dose 50 (ED50)=0.97 mg/kg and 2.17 mg/kg morphine, respectively] than test mice from the less social BALB/cJ (BALB) strain (ED50=0.61 mg/kg and 0.91 mg/kg morphine, respectively). By contrast, this strain-dependent difference was not evident among adult mice on PD 90 (ED50=1.07 mg/kg and 1.41 mg/kg morphine for BALB and B6 mice, respectively). An additional experiment showed that the ability of morphine to alter social responsiveness was not directly related to drug-induced changes in locomotor behavior. Finally, administration of morphine to stimulus mice on PD 25 reduced social investigation of test mice only when individuals were from the B6 genetic background. Overall, these results indicate that alterations in endogenous opioid systems are related to changes in SI that occur during adolescence, and that morphine administration may mimic rewarding aspects of social encounter.
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Abstract
Positive social interactions are essential for emotional well-being and proper behavioral development of young individuals. Here, we studied the neural underpinnings of social reward by investigating the involvement of opioid neurotransmission in the nucleus accumbens (NAc) in social play behavior, a highly rewarding social interaction in adolescent rats. Intra-NAc infusion of morphine (0.05-0.1 μg) increased pinning and pouncing, characteristic elements of social play behavior in rats, and blockade of NAc opioid receptors with naloxone (0.5 μg) prevented the play-enhancing effects of systemic morphine (1 mg/kg, s.c.) administration. Thus, stimulation of opioid receptors in the NAc was necessary and sufficient for morphine to increase social play. Intra-NAc treatment with the selective μ-opioid receptor agonist [D-Ala(2),N-MePhe(4),Gly(5)-ol]enkephalin (DAMGO) (0.1-10 ng) and the μ-opioid receptor antagonist Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH(2) (CTAP) (0.3-3 μg) increased and decreased social play, respectively. The δ-opioid receptor agonist DPDPE ([D-Pen(2),D-Pen(5)]-enkephalin) (0.3-3 μg) had no effects, whereas the κ-opioid receptor agonist U69593 (N-methyl-2-phenyl-N-[(5R,7S,8S)-7-(pyrrolidin-1-yl)-1-oxaspiro[4.5]dec-8-yl]acetamide) (0.01-1 μg) decreased social play. Intra-NAc treatment with β-endorphin (0.01-1 μg) increased social play, but met-enkephalin (0.1-5 μg) and the enkephalinase inhibitor thiorphan (0.1-1 μg) were ineffective. DAMGO (0.1-10 ng) increased social play after infusion into both the shell and core subregions of the NAc. Last, intra-NAc infusion of CTAP (3 μg) prevented the development of social play-induced conditioned place preference. These findings identify NAc μ-opioid receptor stimulation as an important neural mechanism for the attribution of positive value to social interactions in adolescent rats. Altered NAc μ-opioid receptor function may underlie social impairments in psychiatric disorders such as autism, schizophrenia, or personality disorders.
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Lahvis GP, Alleva E, Scattoni ML. Translating mouse vocalizations: prosody and frequency modulation. GENES BRAIN AND BEHAVIOR 2011; 10:4-16. [PMID: 20497235 DOI: 10.1111/j.1601-183x.2010.00603.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Mental illness can include impaired abilities to express emotions or respond to the emotions of others. Speech provides a mechanism for expressing emotions, by both what words are spoken and by the melody or intonation of speech (prosody). Through the perception of variations in prosody, an individual can detect changes in another's emotional state. Prosodic features of mouse ultrasonic vocalizations (USVs), indicated by changes in frequency and amplitude, also convey information. Dams retrieve pups that emit separation calls, females approach males emitting solicitous calls, and mice can become fearful of a cue associated with the vocalizations of a distressed conspecific. Because acoustic features of mouse USVs respond to drugs and genetic manipulations that influence reward circuits, USV analysis can be employed to examine how genes influence social motivation, affect regulation, and communication. The purpose of this review is to discuss how genetic and developmental factors influence aspects of the mouse vocal repertoire and how mice respond to the vocalizations of their conspecifics. To generate falsifiable hypotheses about the emotional content of particular calls, this review addresses USV analysis within the framework of affective neuroscience (e.g. measures of motivated behavior such as conditioned place preference tests, brain activity and systemic physiology). Suggested future studies include employment of an expanded array of physiological and statistical approaches to identify the salient acoustic features of mouse vocalizations. We are particularly interested in rearing environments that incorporate sufficient spatial and temporal complexity to familiarize developing mice with a broader array of affective states.
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Affiliation(s)
- G P Lahvis
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, Oregon 97239-3011, USA.
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Wöhr M, Moles A, Schwarting RKW, D'Amato FR. Lack of social exploratory activation in male μ-opioid receptor KO mice in response to playback of female ultrasonic vocalizations. Soc Neurosci 2011; 6:76-87. [DOI: 10.1080/17470911003765560] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Social Interactions in the Clinic and the Cage: Toward a More Valid Mouse Model of Autism. ANIMAL MODELS OF BEHAVIORAL ANALYSIS 2011. [DOI: 10.1007/978-1-60761-883-6_7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Trezza V, Baarendse PJJ, Vanderschuren LJMJ. The pleasures of play: pharmacological insights into social reward mechanisms. Trends Pharmacol Sci 2010; 31:463-9. [PMID: 20684996 DOI: 10.1016/j.tips.2010.06.008] [Citation(s) in RCA: 263] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Revised: 06/25/2010] [Accepted: 06/28/2010] [Indexed: 12/20/2022]
Abstract
Like human children, most young mammals devote a significant amount of time and energy playing together, and social play is fun. Although social play is very pleasurable, it is more than just a frivolous activity: it is crucial for the development of behavioral flexibility, the acquisition of social and cognitive competence, and the maintenance of group cohesion. Social play is a natural reinforcer, and the neurotransmitter systems intimately implicated in the motivational, pleasurable and cognitive aspects of natural and drug rewards, such as opioids, endocannabinoids, dopamine and norepinephrine, play an important modulatory role in the performance of social play. In this review, we address the notion that social play is rewarding, and discuss recent developments in the neuropharmacology of this behavior. This provides a framework to understand how the brain processes social emotions, to make young individuals enjoy social play.
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Affiliation(s)
- Viviana Trezza
- Department of Neuroscience and Pharmacology, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands.
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Fattore L, Melis M, Fadda P, Pistis M, Fratta W. The endocannabinoid system and nondrug rewarding behaviours. Exp Neurol 2010; 224:23-36. [PMID: 20353776 DOI: 10.1016/j.expneurol.2010.03.020] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Rewarding behaviours such as sexual activity, eating, nursing, parenting, social interactions, and play activity are conserved strongly in evolution, and they are essential for development and survival. All of these behaviours are enjoyable and represent pleasant experiences with a high reward value. Remarkably, rewarding behaviours activate the same brain circuits that mediate the positive reinforcing effects of drugs of abuse and of other forms of addiction, such as gambling and food addiction. Given the involvement of the endocannabinoid system in a variety of physiological functions of the nervous system, it is not surprising that it takes part in the complex machinery that regulates gratification and perception of pleasure. In this review, we focus first on the role of the endocannabinoid system in the modulation of neural activity and synaptic functions in brain regions that are involved in natural and nonnatural rewards (namely, the ventral tegmental area, striatum, amygdala, and prefrontal cortex). Then, we examine the role of the endocannabinoid system in modulating behaviours that directly or indirectly activate these brain reward pathways. More specifically, current knowledge of the effects of the pharmacological manipulation of the endocannabinoid system on natural (eating, sexual behaviour, parenting, and social play) and pathological (gambling) rewarding behaviours is summarised and discussed.
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Affiliation(s)
- Liana Fattore
- CNR Neuroscience Institute - Cagliari, Cittadella Universitaria di Monserrato, Italy
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Ultrasonic communication in rats: Effects of morphine and naloxone on vocal and behavioral responses to playback of 50-kHz vocalizations. Pharmacol Biochem Behav 2009; 94:285-95. [DOI: 10.1016/j.pbb.2009.09.008] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Revised: 09/05/2009] [Accepted: 09/08/2009] [Indexed: 02/05/2023]
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Willey AR, Varlinskaya EI, Spear LP. Social interactions and 50 kHz ultrasonic vocalizations in adolescent and adult rats. Behav Brain Res 2009; 202:122-9. [PMID: 19447288 DOI: 10.1016/j.bbr.2009.03.025] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2008] [Revised: 03/13/2009] [Accepted: 03/19/2009] [Indexed: 10/21/2022]
Abstract
Human adolescents drink partly to facilitate their social interactions, a social facilitatory effect of ethanol also seen in adolescent rats tested under familiar test circumstances. To explore the role of hedonic affect in ethanol-induced social facilitation, this study assessed 50 kHz ultrasonic vocalizations (USVs) in pair-housed adolescent (P29-37) and adult (P71-79) Sprague-Dawley male rats during social interactions. On each of eight test days, animals were socially isolated for 3 h and then injected intraperitoneally with 0 (saline), 0.25 or 0.5 g/kg ethanol. Twenty-five minutes later they were placed alone in a familiar test chamber for a 5-min period, followed by a 10-min encounter with a similarly injected peer. USVs were recorded during this 10-min period, while social interactions were videotaped for later scoring. BECs were measured immediately post-test on day 8. Although the 0.25 g/kg dose of ethanol facilitated play fighting in adolescents but not adults, ethanol had little to no effect on 50 kHz USV production under these test circumstances. USV production was higher in adults than adolescents, despite adolescents consistently engaging in more social behavior. To the extent that 50 kHz USVs index the hedonic value of social interactions, these findings support the conclusion that elevations in social behavior normally evident in adolescents may not be related to increases in hedonic sensitivity for social stimuli.
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Affiliation(s)
- Amanda R Willey
- Department of Psychology, Binghamton University (SUNY), Binghamton, NY 13902, USA.
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