1
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Minshall BL, Skipper RA, Riddle CA, Wasylyshyn CF, Claflin DI, Quinn JJ. Sex differences in acute early life stress-enhanced fear learning in adult rats. Dev Psychobiol 2024; 66:e22511. [PMID: 38837722 DOI: 10.1002/dev.22511] [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: 01/29/2024] [Revised: 05/08/2024] [Accepted: 05/14/2024] [Indexed: 06/07/2024]
Abstract
Patients diagnosed with posttraumatic stress disorder (PTSD) present with a spectrum of debilitating anxiety symptoms resulting from exposure to trauma. Women are twice as likely to be diagnosed with anxiety and PTSD compared to men; however, the reason for this vulnerability remains unknown. We conducted four experiments where we first demonstrated a female vulnerability to stress-enhanced fear learning (SEFL) with a moderate, acute early life stress (aELS) exposure (4 footshocks in a single session), compared to a more intense aELS exposure (15 footshocks in a single session) where males and females demonstrated comparable SEFL. Next, we demonstrated that this female vulnerability does not result from differences in footshock reactivity or contextual fear conditioning during the aELS exposure. Finally, using gonadectomy or sham surgeries in adult male and female rats, we showed that circulating levels of gonadal steroid hormones at the time of adult fear conditioning do not explain the female vulnerability to SEFL. Additional research is needed to determine whether this vulnerability can be explained by organizational effects of gonadal steroid hormones or differences in sex chromosome gene expression. Doing so is critical for a better understanding of increased female vulnerability to certain psychiatric diseases.
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Affiliation(s)
- Brianna L Minshall
- Department of Psychology and Center for Neuroscience and Behavior, Miami University, Oxford, Ohio, USA
| | - Rachel A Skipper
- Department of Psychology and Center for Neuroscience and Behavior, Miami University, Oxford, Ohio, USA
| | - Collin A Riddle
- Department of Psychology and Center for Neuroscience and Behavior, Miami University, Oxford, Ohio, USA
| | - Catherine F Wasylyshyn
- Department of Psychology and Center for Neuroscience and Behavior, Miami University, Oxford, Ohio, USA
| | - Dragana I Claflin
- Department of Psychology, Wright State University, Dayton, Ohio, USA
| | - Jennifer J Quinn
- Department of Psychology and Center for Neuroscience and Behavior, Miami University, Oxford, Ohio, USA
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2
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Premachandran H, Wilkin J, Arruda-Carvalho M. Minimizing Variability in Developmental Fear Studies in Mice: Toward Improved Replicability in the Field. Curr Protoc 2024; 4:e1040. [PMID: 38713136 DOI: 10.1002/cpz1.1040] [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] [Indexed: 05/08/2024]
Abstract
In rodents, the first weeks of postnatal life feature remarkable changes in fear memory acquisition, retention, extinction, and discrimination. Early development is also marked by profound changes in brain circuits underlying fear memory processing, with heightened sensitivity to environmental influences and stress, providing a powerful model to study the intersection between brain structure, function, and the impacts of stress. Nevertheless, difficulties related to breeding and housing young rodents, preweaning manipulations, and potential increased variability within that population pose considerable challenges to developmental fear research. Here we discuss several factors that may promote variability in studies examining fear conditioning in young rodents and provide recommendations to increase replicability. We focus primarily on experimental conditions, design, and analysis of rodent fear data, with an emphasis on mouse studies. The convergence of anatomical, synaptic, physiological, and behavioral changes during early life may increase variability, but careful practice and transparency in reporting may improve rigor and consensus in the field. © 2024 The Authors. Current Protocols published by Wiley Periodicals LLC.
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Affiliation(s)
- Hanista Premachandran
- Department of Psychology, University of Toronto Scarborough, Toronto, Ontario, Canada
- These authors contributed equally to this work
| | - Jennifer Wilkin
- Department of Psychology, University of Toronto Scarborough, Toronto, Ontario, Canada
- These authors contributed equally to this work
| | - Maithe Arruda-Carvalho
- Department of Psychology, University of Toronto Scarborough, Toronto, Ontario, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
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3
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Malik S, Park CHJ, Kim JH. Age-specific sex effects in extinction of conditioned fear in rodents. Front Behav Neurosci 2023; 17:1298164. [PMID: 38161359 PMCID: PMC10756678 DOI: 10.3389/fnbeh.2023.1298164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 11/10/2023] [Indexed: 01/03/2024] Open
Affiliation(s)
- Sajida Malik
- School of Medicine, Institute for Mental and Physical Health and Clinical Translation, Deakin University, Geelong, VIC, Australia
| | - Chun Hui J. Park
- School of Medicine, Institute for Mental and Physical Health and Clinical Translation, Deakin University, Geelong, VIC, Australia
| | - Jee Hyun Kim
- School of Medicine, Institute for Mental and Physical Health and Clinical Translation, Deakin University, Geelong, VIC, Australia
- Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
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4
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Meyer HC, Lee FS. Intermixed safety cues facilitate extinction retention in adult and adolescent mice. Physiol Behav 2023; 271:114336. [PMID: 37619817 PMCID: PMC10592038 DOI: 10.1016/j.physbeh.2023.114336] [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: 05/15/2023] [Revised: 08/01/2023] [Accepted: 08/21/2023] [Indexed: 08/26/2023]
Abstract
Extinction learning is tremendously adaptive as it allows an animal to adjust their behavior in a changing environment. Yet, extinction is not without limitations and fear often reemerges over time (i.e. spontaneous recovery). Relative to adults, adolescent rodents and humans are particularly prone to spontaneous recovery following extinction. In this study, we aimed to address whether combining methods of fear regulation (extinction and conditioned inhibition) can facilitate extinction retention. Early adolescent (29 days old, n = 81) and adult (70 days old, n = 80) mice underwent extinction with or without a safety cue present. Safety cue presentations were systematically varied to overlap with or alternate with fear cue presentations. We found that initial safety learning was faster in adolescent mice. In addition, intermixing safety cues into extinction reduced spontaneous recovery during a test two weeks later. The decrease in spontaneous recovery relative to a standard extinction protocol was greater in adolescents than adults. Together, our findings provide initial evidence that safety learning may be inherently stronger during adolescence. These results inform the parameters by which conditioned safety and extinction learning may be merged to augment the inhibition of fear. While methods to enhance fear regulation are valuable for any age, the potential to do so during adolescence is particularly striking.
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Affiliation(s)
- Heidi C Meyer
- Department of Psychological and Brain Sciences, Boston University, 610 Commonwealth Avenue, Boston, MA 02215, USA; Department of Psychiatry, Weill Cornell Medicine, New York, NY, USA.
| | - Francis S Lee
- Department of Psychiatry, Weill Cornell Medicine, New York, NY, USA
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5
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Shih CW, Chang CH. Inactivation of medial or lateral orbitofrontal cortex during fear extinction did not interfere with fear renewal. Neurobiol Learn Mem 2023; 204:107800. [PMID: 37524199 DOI: 10.1016/j.nlm.2023.107800] [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: 03/27/2023] [Revised: 07/17/2023] [Accepted: 07/28/2023] [Indexed: 08/02/2023]
Abstract
Hyperactive orbitofrontal cortical activation is commonly seen in patients of obsessive-compulsive disorder (OCD). Previous studies from our laboratory showed that for rats with aberrant activation of the orbitofrontal cortex (OFC) during the extinction phase, they were unable to use contexts as the reference for proper retrieval of fear memory during renewal test. This result supported the phenomenon that many OCD patients show poor regulation of fear-related behavior. Since there are robust anatomical connections of the OFC with the fear-circuit, we aim to further examine whether the OFC is actively engaged in fear regulation under normal circumstances. In this study, the lateral or medial OFC was inactivated during the extinction phase using the ABA fear renewal procedure. We found that these animals showed intact fear renewal during retrieval test with their freezing levels equivalent to the control rats, revealing that the OFC did not have decisive roles in extinction acquisition. Together with our previous study, we suggest that the OFC only interferes with fear regulation when it becomes pathophysiologically hyperactive.
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Affiliation(s)
- Cheng-Wei Shih
- Institute of Systems Neuroscience, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Chun-Hui Chang
- Institute of Systems Neuroscience, National Tsing Hua University, Hsinchu 30013, Taiwan; Brain Research Center, National Tsing Hua University, Hsinchu 30013, Taiwan.
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6
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Towner E, Chierchia G, Blakemore SJ. Sensitivity and specificity in affective and social learning in adolescence. Trends Cogn Sci 2023:S1364-6613(23)00092-X. [PMID: 37198089 DOI: 10.1016/j.tics.2023.04.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 03/23/2023] [Accepted: 04/05/2023] [Indexed: 05/19/2023]
Abstract
Adolescence is a period of heightened affective and social sensitivity. In this review we address how this increased sensitivity influences associative learning. Based on recent evidence from human and rodent studies, as well as advances in computational biology, we suggest that, compared to other age groups, adolescents show features of heightened Pavlovian learning but tend to perform worse than adults at instrumental learning. Because Pavlovian learning does not involve decision-making, whereas instrumental learning does, we propose that these developmental differences might be due to heightened sensitivity to rewards and threats in adolescence, coupled with a lower specificity of responding. We discuss the implications of these findings for adolescent mental health and education.
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Affiliation(s)
- Emily Towner
- Department of Psychology, University of Cambridge, Downing Street, Cambridge, UK.
| | - Gabriele Chierchia
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy; Department of Psychology, University of Cambridge, Downing Street, Cambridge, UK
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7
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Bonifacino T, Mingardi J, Facchinetti R, Sala N, Frumento G, Ndoj E, Valenza M, Paoli C, Ieraci A, Torazza C, Balbi M, Guerinoni M, Muhammad N, Russo I, Milanese M, Scuderi C, Barbon A, Steardo L, Bonanno G, Popoli M, Musazzi L. Changes at glutamate tripartite synapses in the prefrontal cortex of a new animal model of resilience/vulnerability to acute stress. Transl Psychiatry 2023; 13:62. [PMID: 36806044 PMCID: PMC9938874 DOI: 10.1038/s41398-023-02366-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 02/08/2023] [Accepted: 02/10/2023] [Indexed: 02/20/2023] Open
Abstract
Stress represents a main risk factor for psychiatric disorders. Whereas it is known that even a single trauma may induce psychiatric disorders in humans, the mechanisms of vulnerability to acute stressors have been little investigated. In this study, we generated a new animal model of resilience/vulnerability to acute footshock (FS) stress in rats and analyzed early functional, molecular, and morphological determinants of stress vulnerability at tripartite glutamate synapses in the prefrontal cortex (PFC). We found that adult male rats subjected to FS can be deemed resilient (FS-R) or vulnerable (FS-V), based on their anhedonic phenotype 24 h after stress exposure, and that these two populations are phenotypically distinguishable up to two weeks afterwards. Basal presynaptic glutamate release was increased in the PFC of FS-V rats, while depolarization-evoked glutamate release and synapsin I phosphorylation at Ser9 were increased in both FS-R and FS-V. In FS-R and FS-V rats the synaptic expression of GluN2A and apical dendritic length of prelimbic PFC layers II-III pyramidal neurons were decreased, while BDNF expression was selectively reduced in FS-V. Depolarization-evoked (carrier-mediated) glutamate release from astroglia perisynaptic processes (gliosomes) was selectively increased in the PFC of FS-V rats, while GLT1 and xCt levels were higher and GS expression reduced in purified PFC gliosomes from FS-R. Overall, we show for the first time that the application of the sucrose intake test to rats exposed to acute FS led to the generation of a novel animal model of resilience/vulnerability to acute stress, which we used to identify early determinants of maladaptive response related to behavioral vulnerability to stress.
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Affiliation(s)
- Tiziana Bonifacino
- grid.5606.50000 0001 2151 3065Department of Pharmacy, Unit of Pharmacology and Toxicology, University of Genoa, Genoa, Italy
| | - Jessica Mingardi
- grid.7563.70000 0001 2174 1754School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy ,grid.7637.50000000417571846Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Roberta Facchinetti
- grid.7841.aDepartment of Physiology and Pharmacology “Vittorio Erspamer”, SAPIENZA University of Rome, Rome, Italy
| | - Nathalie Sala
- grid.4708.b0000 0004 1757 2822Laboratory of Neuropsychopharmacology and Functional Neurogenomics, Dipartimento di Scienze Farmaceutiche, Università Degli Studi di Milano, Milano, Italy
| | - Giulia Frumento
- grid.5606.50000 0001 2151 3065Department of Pharmacy, Unit of Pharmacology and Toxicology, University of Genoa, Genoa, Italy
| | - Elona Ndoj
- grid.7637.50000000417571846Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Marta Valenza
- grid.7841.aDepartment of Physiology and Pharmacology “Vittorio Erspamer”, SAPIENZA University of Rome, Rome, Italy
| | - Caterina Paoli
- grid.7563.70000 0001 2174 1754School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy ,grid.5602.10000 0000 9745 6549Pharmacology Unit, School of Pharmacy, University of Camerino, Camerino, Italy
| | - Alessandro Ieraci
- grid.4708.b0000 0004 1757 2822Laboratory of Neuropsychopharmacology and Functional Neurogenomics, Dipartimento di Scienze Farmaceutiche, Università Degli Studi di Milano, Milano, Italy ,grid.449889.00000 0004 5945 6678Department of Theoretical and Applied Sciences, eCampus University, Novedrate, Como, Italy
| | - Carola Torazza
- grid.5606.50000 0001 2151 3065Department of Pharmacy, Unit of Pharmacology and Toxicology, University of Genoa, Genoa, Italy
| | - Matilde Balbi
- grid.5606.50000 0001 2151 3065Department of Pharmacy, Unit of Pharmacology and Toxicology, University of Genoa, Genoa, Italy
| | - Michele Guerinoni
- grid.4708.b0000 0004 1757 2822Laboratory of Neuropsychopharmacology and Functional Neurogenomics, Dipartimento di Scienze Farmaceutiche, Università Degli Studi di Milano, Milano, Italy
| | - Nadeem Muhammad
- grid.5606.50000 0001 2151 3065Department of Pharmacy, Unit of Pharmacology and Toxicology, University of Genoa, Genoa, Italy
| | - Isabella Russo
- grid.7637.50000000417571846Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy ,Genetics Unit, IRCCS Istituto Centro S. Giovanni di Dio, Fatebenefratelli, 25125 Brescia, Italy
| | - Marco Milanese
- grid.5606.50000 0001 2151 3065Department of Pharmacy, Unit of Pharmacology and Toxicology, University of Genoa, Genoa, Italy ,grid.410345.70000 0004 1756 7871IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Caterina Scuderi
- grid.7841.aDepartment of Physiology and Pharmacology “Vittorio Erspamer”, SAPIENZA University of Rome, Rome, Italy
| | - Alessandro Barbon
- grid.7637.50000000417571846Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Luca Steardo
- grid.7841.aDepartment of Physiology and Pharmacology “Vittorio Erspamer”, SAPIENZA University of Rome, Rome, Italy
| | - Giambattista Bonanno
- grid.5606.50000 0001 2151 3065Department of Pharmacy, Unit of Pharmacology and Toxicology, University of Genoa, Genoa, Italy ,grid.410345.70000 0004 1756 7871IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Maurizio Popoli
- Laboratory of Neuropsychopharmacology and Functional Neurogenomics, Dipartimento di Scienze Farmaceutiche, Università Degli Studi di Milano, Milano, Italy.
| | - Laura Musazzi
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy.
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8
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Velasco ER, Florido A, Perez-Caballero L, Marin I, Andero R. The Impacts of Sex Differences and Sex Hormones on Fear Extinction. Curr Top Behav Neurosci 2023; 64:105-132. [PMID: 37528309 DOI: 10.1007/7854_2023_426] [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] [Indexed: 08/03/2023]
Abstract
Fear extinction memories are strongly modulated by sex and hormonal status, but the exact mechanisms are still being discovered. In humans, there are some basal and task-related features in which male and female individuals differ in fear conditioning paradigms. However, analyses considering the effects of sex hormones demonstrate a role for estradiol in fear extinction memory consolidation. Translational studies are taking advantage of the convergent findings between species to understand the brain structures implicated. Nevertheless, the human brain is complex and the transfer of these findings into the clinics remains a challenge. The promising advances in the field together with the standardization of fear extinction methodologies in humans will benefit the design of new personalized therapies.
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Affiliation(s)
- Eric Raul Velasco
- Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Antonio Florido
- Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain
- Departament de Psicobiologia i de Metodologia de les Ciències de la Salut, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Laura Perez-Caballero
- Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain
- Departament de Psicobiologia i de Metodologia de les Ciències de la Salut, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Ignacio Marin
- Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Raul Andero
- Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain.
- Departament de Psicobiologia i de Metodologia de les Ciències de la Salut, Universitat Autònoma de Barcelona, Barcelona, Spain.
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain.
- Unitat de Neurociència Traslacional, Parc Taulí Hospital Universitari, Institut d'Investigació i Innovació Parc Taulí (I3PT), Institut de Neurociències, Universitat Autònoma de Barcelona, Bellaterra, Spain.
- ICREA, Pg. Lluís Companys 23, Barcelona, Spain.
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9
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Glavonic E, Mitic M, Francija E, Petrovic Z, Adzic M. Sex-specific role of hippocampal NMDA-Erk-mTOR signaling in fear extinction of adolescent mice. Brain Res Bull 2023; 192:156-167. [PMID: 36410566 DOI: 10.1016/j.brainresbull.2022.11.011] [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: 08/05/2022] [Revised: 09/26/2022] [Accepted: 11/17/2022] [Indexed: 11/19/2022]
Abstract
Adolescence is a key phase of development for perturbations in fear extinction, with inability to adequately manage fear a potent factor for developing psychiatric disorders in adulthood. However, while behavioral correlates of adolescent fear regulation are established to a degree, molecular mediators of extinction learning in adolescence remain largely unknown. In this study, we observed fear acquisition and fear extinction (across 4 and 7 days) of adolescent and adult mice of both sexes and investigated how hippocampal levels of different plasticity markers relate to extinction learning. While fear was acquired evenly in males and females of both ages, fear extinction was found to be impaired in adolescent males. We also observed lower levels of GluA1, GLUN2A and GLUN2B subunits in male adolescents following fear acquisition, with an increase in their expression, as well as the activity of Erk-mTOR pathway over subsequent extinction sessions, which was paralleled with improved extinction learning. On the other hand, we detected no changes in plasticity-related proteins after fear acquisition in females, with alterations in GluA1, GluA4 and GLUN2B levels across fear extinction sessions. Additionally, we did not discern any pattern regarding the Erk-mTOR activity in female mice associated with their extinction performance. Overall, our research identifies sex-specific synaptic properties in the hippocampus that underlie developmentally regulated differences in fear extinction learning. We also point out hippocampal NMDA-Erk-mTOR signaling as the driving force behind successful fear extinction in male adolescents, highlighting this pathway as a potential therapeutic target for fear-related disorders in the adolescent population.
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Affiliation(s)
- Emilija Glavonic
- Department of Molecular Biology and Endocrinology, "VINČA" Institute of Nuclear Sciences-National Institute of thе Republic of Serbia, University of Belgrade, Belgrade, Serbia.
| | - Milos Mitic
- Department of Molecular Biology and Endocrinology, "VINČA" Institute of Nuclear Sciences-National Institute of thе Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Ester Francija
- Department of Molecular Biology and Endocrinology, "VINČA" Institute of Nuclear Sciences-National Institute of thе Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Zorica Petrovic
- Department of Molecular Biology and Endocrinology, "VINČA" Institute of Nuclear Sciences-National Institute of thе Republic of Serbia, University of Belgrade, Belgrade, Serbia; Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Miroslav Adzic
- Department of Molecular Biology and Endocrinology, "VINČA" Institute of Nuclear Sciences-National Institute of thе Republic of Serbia, University of Belgrade, Belgrade, Serbia
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10
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Rubio Arzola P, Shansky RM. Considering Organismal Physiology in Laboratory Studies of Rodent Behavior. Annu Rev Neurosci 2022; 45:387-402. [PMID: 35395164 DOI: 10.1146/annurev-neuro-111020-085500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Any experiment conducted in a rodent laboratory is done so against the backdrop of each animal's physiological state at the time of the experiment. This physiological state can be the product of multiple factors, both internal (e.g., animal sex, strain, hormone cycles, or circadian rhythms) and external (e.g., housing conditions, social status, and light/dark phases). Each of these factors has the potential to influence experimental outcomes, either independently or via interactions with others, and yet there is little consistency across laboratories in terms of the weight with which they are considered in experimental design. Such discrepancies-both in practice and in reporting-likely contribute to the perception of a reproducibility crisis in the field of behavioral neuroscience. In this review, we discuss how several of these sources of variability can impact outcomes within the realm of common learning and memory paradigms. Expected final online publication date for the Annual Review of Neuroscience, Volume 45 is July 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
| | - Rebecca M Shansky
- Department of Psychology, Northeastern University, Boston, Massachusetts, USA;
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11
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Sex-dependent effects of chronic exercise on cognitive flexibility but not hippocampal Bdnf in aging mice. Neuronal Signal 2022; 6:NS20210053. [PMID: 35036000 PMCID: PMC8734434 DOI: 10.1042/ns20210053] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 11/22/2021] [Accepted: 12/08/2021] [Indexed: 01/02/2023] Open
Abstract
Cognitive impairments associated with advanced age involve alterations in the hippocampus that changes with experience throughout life. The hippocampus is critical for cognitive flexibility involved with extinction and reinstatement of conditioned fear. It is widely accepted that regular exercise can be beneficial for hippocampal function. Therefore, we asked whether chronic voluntary exercise in middle-aged mice can improve extinction and/or reinstatement of conditioned fear compared with standard-housing. Eight-month-old male and female C57Bl/6J mice had access to a running wheel or remained in standard-housing until 11 months of age. Alongside control standard-housed young adult (3-month-old) mice, they received tone-footshock pairings, which were subsequently extinguished with tone-alone presentations the next day. Half of the mice then received a reminder in the form of a single footshock. Male and female 11-month-old mice housed in standard conditions exhibited impaired reinstatement compared with young adult mice. However, for males that had access to a running wheel from 8 months of age, the reminder treatment rescued reinstatement ability. This was not observed in females. Additionally, exercise during middle age in both sexes increased expression of brain-derived neurotrophic factor (Bdnf) mRNA in the hippocampus, specifically exon 4 mRNA. These results show that, at least for males, physical exercise is beneficial for reducing age-related decline in cognitive abilities. Despite not affecting reinstatement, exercise also increased Bdnf gene expression in the female hippocampus, which could potentially benefit other forms of hippocampus-dependent cognition.
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12
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Qing X, Xu YL, Liu H, Liu XS. The influence of anesthesia and surgery on fear extinction. Neurosci Lett 2022; 766:136347. [PMID: 34808271 DOI: 10.1016/j.neulet.2021.136347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 08/29/2021] [Accepted: 11/09/2021] [Indexed: 10/19/2022]
Abstract
Accumulating evidence has demonstrated significant clinical post-traumatic stress disorder (PTSD) symptoms after anesthesia or surgery. Fear extinction dysfunction is a notable feature of PTSD. Although anesthetics and surgery profoundly affect memory processes, their designated effects on fear extinction have not been dissertated. Previous studies have suggested that innate immune system activation disrupts fear extinction, and surgery has been shown to increase the inflammatory response. Thus, in the current study, we examined the effects of propofol, sevoflurane, dexmedetomidine and surgery on fear extinction in adolescent mice, and further tested whether dexmedetomidine could reverse the injury effect of surgery on fear extinction through its anti-inflammatory effects. Our results showed that propofol (200 mg/kg) impaired the acquisition and recall of cued fear extinction, and surgery disrupted cued fear extinction acquisition/recall and consolidation. In contrast to cued fear extinction, contextual fear extinction was not affected by propofol or surgery. Moreover, dexmedetomidine prevented surgery-induced impairment of cued extinction acquisition and recall but not consolidation. Finally, TNF-α and IL-6 levels in the ventromedial prefrontal cortex were not necessary for the dexmedetomidine treatment effect of surgery-induced fear extinction dysfunction. The study results showed that propofol and surgery selective impaired the cued fear extinction stage in adolescent mice, and dexmedetomidine may unleash a protective effect in preventing postoperative PTSD.
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Affiliation(s)
- Xin Qing
- Department of Anesthesiology, the First Affiliated Hospital of Anhui Medical University, Key Laboratory of Anesthesiology and Perioperative Medicine of Anhui Higher Education Institutes, Anhui Medical University, China
| | - Yuan-Ling Xu
- Department of Anesthesiology, the First Affiliated Hospital of Anhui Medical University, Key Laboratory of Anesthesiology and Perioperative Medicine of Anhui Higher Education Institutes, Anhui Medical University, China
| | - Hu Liu
- Department of Anesthesiology, the First Affiliated Hospital of Anhui Medical University, Key Laboratory of Anesthesiology and Perioperative Medicine of Anhui Higher Education Institutes, Anhui Medical University, China.
| | - Xue-Sheng Liu
- Department of Anesthesiology, the First Affiliated Hospital of Anhui Medical University, Key Laboratory of Anesthesiology and Perioperative Medicine of Anhui Higher Education Institutes, Anhui Medical University, China.
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13
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Gerhard DM, Meyer HC. Extinction trial spacing across days differentially impacts fear regulation in adult and adolescent male mice. Neurobiol Learn Mem 2021; 186:107543. [PMID: 34748926 PMCID: PMC8744067 DOI: 10.1016/j.nlm.2021.107543] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 10/15/2021] [Accepted: 10/25/2021] [Indexed: 01/09/2023]
Abstract
Fear regulation changes as a function of age and adolescence is a key developmental period for the continued maturation of fear neural circuitry. A consistent finding in the literature is diminished extinction retention in adolescents. However, these studies often directly compare adolescents to adults using a single protocol and therefore provide little insight into learning parameters that improve adolescent fear regulation. Studies in adults highlight the benefits of spaced learning over massed learning. These findings have been extended to fear regulation, with adult rodents exhibiting improved extinction learning and retention when cues are distributed over days versus a single session. However, similar studies have not been performed in adolescents. Here, we systematically examine the impact of trial spacing across days on fear regulation. Adolescent or adult male mice were exposed to one of three extinction paradigms that presented the same number of trials but differed in the temporal distribution of trials across days (one day, two days, or four days). We found that introducing consolidation events into the protocol improves adult extinction learning and short-term extinction retention but these effects disappear after two weeks. For adolescents, all three protocols were comparably effective in reducing freezing across extinction training and improved retention at both short-term and long-term fear recall time points relative to extinction-naive mice. These findings suggest that extinction protocols that incorporate consolidation events are optimal for adults but additional booster training may be required for enduring efficacy. In contrast, protocols incorporating either massed or spaced presentations show immediate and enduring benefits for adolescents.
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Affiliation(s)
- Danielle M Gerhard
- Department of Psychiatry, Weill Cornell Medicine, New York, NY, United States.
| | - Heidi C Meyer
- Department of Psychiatry, Weill Cornell Medicine, New York, NY, United States; Department of Psychological and Brain Sciences, Boston University, Boston, MA, United States.
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14
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Bisby MA, Stylianakis AA, Baker KD, Richardson R. Fear extinction learning and retention during adolescence in rats and mice: A systematic review. Neurosci Biobehav Rev 2021; 131:1264-1274. [PMID: 34740753 DOI: 10.1016/j.neubiorev.2021.10.044] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 10/20/2021] [Accepted: 10/29/2021] [Indexed: 10/19/2022]
Abstract
Despite exposure-based treatments being recommended for anxiety disorders, these treatments are ineffective for over half of all adolescents who receive them. The limited efficacy of exposure during adolescence may be driven by a deficit in extinction. Although indications of diminished extinction learning during adolescence were first reported over 10 years ago, these findings have yet to be reviewed and compared. This review (k = 34) found a stark inter-species difference in extinction performance: studies of adolescent mice reported deficits in extinction learning and retention of both cued and context fear. In contrast, studies of adolescent rats only reported poor extinction retention specific to cued fear. Adolescent mice and rats appeared to have only one behavioral outcome in common, being poor extinction retention of cued fear. These findings suggest that different behavioral phenotypes are present across rodent species in adolescence and highlight that preclinical work in rats and mice is not interchangeable. Further investigation of these differences offers the opportunity to better understand the etiology, maintenance, and treatment of fear-based disorders.
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Affiliation(s)
- Madelyne A Bisby
- School of Psychology, UNSW Sydney, Sydney, 2052, NSW, Australia; eCentreClinic, School of Psychological Sciences, Faculty of Medicine and Health, Macquarie University, Sydney, 2109, NSW, Australia.
| | | | - Kathryn D Baker
- School of Psychology, UNSW Sydney, Sydney, 2052, NSW, Australia
| | - Rick Richardson
- School of Psychology, UNSW Sydney, Sydney, 2052, NSW, Australia
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15
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Drzewiecki CM, Sellinger EP, Juraska JM. Impact of pubertal onset on region-specific Esr2 expression. J Neuroendocrinol 2021; 33:e13029. [PMID: 34463394 PMCID: PMC8448167 DOI: 10.1111/jne.13029] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 07/12/2021] [Accepted: 08/08/2021] [Indexed: 11/28/2022]
Abstract
In female rats, pubertal onset is associated with maturation of the medial prefrontal cortex (mPFC) and mPFC-mediated behaviours. These behavioural and anatomical changes are likely a result of the effects of oestrogens at the nuclear oestrogen receptor (ER)β, which is expressed at higher levels than the ERα isoform in the adult mPFC. Researchers have previously quantified ERβ protein and Esr2 RNA in rodents during early postnatal development and adulthood, although an adolescent-specific trajectory of this receptor in the mPFC has not been documented. Given that Esr2 expression can fluctuate in the presence or absence of oestrogens, puberty and the subsequent rise in gonadal hormones could influence levels of ERβ in the adolescent brain. To further explore this, we used RNAscope® technology to quantify the amount of Esr2 mRNA in pre-pubertal adolescent, recently post-pubertal adolescent and adult female rats. We show that Esr2 expression decreases significantly in the mPFC, striatum and motor cortex between pre-pubertal adolescence and adulthood. In the mPFC, this decrease occurs rapidly at pubertal onset, with no significant decrease in Esr2 levels between the recently post-pubertal and adult cohort. By contrast, the striatum and motor cortex had no significant differences in the amount of Esr2 mRNA between pre- and post-pubertal females. Insofar as the amount of Esr2 expression is proportional to functional ERβ, these results suggest ERβ decreases in a region-specific pattern in response to pubertal onset and highlight a role for this receptor in the maturational events that occur in the female rat mPFC at puberty.
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Affiliation(s)
- Carly M. Drzewiecki
- Program in Neuroscience, University of Illinois at Urbana-Champaign, Champaign, IL 61820
- Currently at California National Primate Research Center, University of California-Davis, Davis, CA, 95616
| | - Elli P. Sellinger
- Program in Neuroscience, University of Illinois at Urbana-Champaign, Champaign, IL 61820
| | - Janice M. Juraska
- Program in Neuroscience, University of Illinois at Urbana-Champaign, Champaign, IL 61820
- Department of Psychology, University of Illinois at Urbana-Champaign, Champaign, IL, 61820
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16
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Drummond KD, Waring ML, Faulkner GJ, Blewitt ME, Perry CJ, Kim JH. Hippocampal neurogenesis mediates sex-specific effects of social isolation and exercise on fear extinction in adolescence. Neurobiol Stress 2021; 15:100367. [PMID: 34337114 PMCID: PMC8313755 DOI: 10.1016/j.ynstr.2021.100367] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 06/30/2021] [Accepted: 07/12/2021] [Indexed: 12/15/2022] Open
Abstract
Impaired extinction of conditioned fear is associated with anxiety disorders. Common lifestyle factors, like isolation stress and exercise, may alter the ability to extinguish fear. However, the effect of and interplay between these factors on adolescent fear extinction, and the relevant underlying neural mechanisms are unknown. Here we examined the effects of periadolescent social isolation and physical activity on adolescent fear extinction in rats and explored neurogenesis as a potential mechanism. Isolation stress impaired extinction recall in male adolescents, an effect prevented by exercise. Extinction recall in female adolescents was unaffected by isolation stress. However, exercise disrupted extinction recall in isolated females. Extinction recall in isolated females was positively correlated to the number of immature neurons in the ventral hippocampus, suggesting that exercise affected extinction recall via neurogenesis in females. Pharmacologically suppressing cellular proliferation in isolated adolescents using temozolomide blocked the effect of exercise on extinction recall in both sexes. Together, these findings highlight sex-specific outcomes of isolation stress and exercise on adolescent brain and behavior, and highlights neurogenesis as a potential mechanism underlying lifestyle effects on adolescent fear extinction. Periadolescent isolation stress disrupted extinction recall in male adolescents. Running prevented isolation-induced extinction recall deficit in male adolescents. Exercise impaired extinction recall in isolated female adolescents. Exercise increased hippocampal neurogenesis, except in isolated males. Suppression of neurogenesis blocked exercise effects in isolated adolescents.
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Affiliation(s)
- Katherine D Drummond
- Mental Health Theme, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3052, Australia.,Florey Department of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, 3052, Australia
| | - Michelle L Waring
- Florey Department of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, 3052, Australia
| | - Geoffrey J Faulkner
- Mater Research Institute - University of Queensland, Woolloongabba, QLD, 4102, Australia.,Queensland Brain Institute, University of Queensland, St. Lucia, QLD, 4067, Australia
| | - Marnie E Blewitt
- The Epigenetics and Development Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia.,The Department of Medical Biology, University of Melbourne, Parkville, VIC, 3052, Australia
| | - Christina J Perry
- Mental Health Theme, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3052, Australia.,Florey Department of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, 3052, Australia
| | - Jee Hyun Kim
- Mental Health Theme, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3052, Australia.,Florey Department of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, 3052, Australia.,IMPACT - the Institute for Mental and Physical Health and Clinical Translation, School of Medicine, Deakin University, Geelong, Australia
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17
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Florido A, Perez-Caballero L, Velasco ER, Molina P, Marin-Blasco I, Andero R. Direct and Indirect Measurements of Sex Hormones in Rodents During Fear Conditioning. Curr Protoc 2021; 1:e102. [PMID: 33950571 DOI: 10.1002/cpz1.102] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Fear conditioning (FC) is a widely accepted tool for the assessment of learning and memory processes in rodents related to normal and dysregulated acquired fear. The study of sex differences in fear learning and memory is vast and currently increasing. Sex hormones have proven to be crucial for fear memory formation in males and females, and several methods have been developed to assess this hormonal state in rats and mice. Herein, we explain a routine FC and extinction protocol, together with the evaluation of sex hormonal state in male and female rodents. We explain three protocols for the evaluation of this hormonal state directly from blood samples extracted during the procedure or indirectly through histological verification of the estrous cycle for females or behavioral assessment of social hierarchies in males. Although females have typically been considered to present great variability in sex hormones, it is highlighted that sex hormone assessment in males is as variable as in females and equally important for fear memory formation. The readout of these protocols has had a great impact on different fields of fear learning and memory study and appears essential when studying FC. The proven interaction with drugs involved in the modulation of these processes makes sex hormone assessment during FC a valuable tool for the development of effective treatments for fear-related disorders in men and women. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Fear conditioning and fear extinction Basic Protocol 2: Blood collection for direct measurement of sex hormone levels in fear conditioning Basic Protocol 3: Indirect measurement of sex hormones in females during fear conditioning Basic Protocol 4: Assessment of dominance status in males before a fear conditioning protocol Support Protocol: Construction of a confrontation tube.
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Affiliation(s)
- Antonio Florido
- Institut de Neurociències, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain
- Departament de Psicobiologia i de Metodologia de les Ciències de la Salut, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain
| | - Laura Perez-Caballero
- Institut de Neurociències, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain
- Departament de Psicobiologia i de Metodologia de les Ciències de la Salut, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain
| | - Eric Raúl Velasco
- Institut de Neurociències, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain
| | - Patricia Molina
- Institut de Neurociències, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain
- Unitat de Fisiologia Animal (Departament de Biologia Cel·lular, Fisiologia i Immunologia), Facultat de Biociències, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain
| | - Ignacio Marin-Blasco
- Institut de Neurociències, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain
| | - Raül Andero
- Institut de Neurociències, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain
- Departament de Psicobiologia i de Metodologia de les Ciències de la Salut, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III, Madrid, Spain
- Unitat de Neurociència Traslacional, Parc Taulí Hospital Universitari, Institut d'Investigació i Innovació Parc Taulí (I3PT), Institut de Neurociències, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
- ICREA, Barcelona, Spain
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18
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Bouton ME, Maren S, McNally GP. BEHAVIORAL AND NEUROBIOLOGICAL MECHANISMS OF PAVLOVIAN AND INSTRUMENTAL EXTINCTION LEARNING. Physiol Rev 2021; 101:611-681. [PMID: 32970967 PMCID: PMC8428921 DOI: 10.1152/physrev.00016.2020] [Citation(s) in RCA: 153] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
This article reviews the behavioral neuroscience of extinction, the phenomenon in which a behavior that has been acquired through Pavlovian or instrumental (operant) learning decreases in strength when the outcome that reinforced it is removed. Behavioral research indicates that neither Pavlovian nor operant extinction depends substantially on erasure of the original learning but instead depends on new inhibitory learning that is primarily expressed in the context in which it is learned, as exemplified by the renewal effect. Although the nature of the inhibition may differ in Pavlovian and operant extinction, in either case the decline in responding may depend on both generalization decrement and the correction of prediction error. At the neural level, Pavlovian extinction requires a tripartite neural circuit involving the amygdala, prefrontal cortex, and hippocampus. Synaptic plasticity in the amygdala is essential for extinction learning, and prefrontal cortical inhibition of amygdala neurons encoding fear memories is involved in extinction retrieval. Hippocampal-prefrontal circuits mediate fear relapse phenomena, including renewal. Instrumental extinction involves distinct ensembles in corticostriatal, striatopallidal, and striatohypothalamic circuits as well as their thalamic returns for inhibitory (extinction) and excitatory (renewal and other relapse phenomena) control over operant responding. The field has made significant progress in recent decades, although a fully integrated biobehavioral understanding still awaits.
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Affiliation(s)
- Mark E Bouton
- Department of Psychological Science, University of Vermont, Burlington, Vermont
| | - Stephen Maren
- Department of Psychological and Brain Sciences and Institute for Neuroscience, Texas A&M University, College Station, Texas
| | - Gavan P McNally
- School of Psychology, University of New South Wales, Sydney, Australia
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19
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An Adolescent Sensitive Period for Threat Responding: Impacts of Stress and Sex. Biol Psychiatry 2021; 89:651-658. [PMID: 33342545 PMCID: PMC7954972 DOI: 10.1016/j.biopsych.2020.10.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 09/30/2020] [Accepted: 10/05/2020] [Indexed: 11/22/2022]
Abstract
Anxiety and fear-related disorders peak in prevalence during adolescence, a window of rapid behavioral development and neural remodeling. However, understanding of the development of threat responding and the underlying neural circuits remains limited. Preclinical models of threat conditioning and extinction have provided an unparalleled glimpse into the developing brain. In this review we discuss mouse and rat studies on the development of threat response regulation, with a focus on the adolescent period. Evidence of nonlinear patterns of threat responding during adolescence and the continued development of the underlying circuitry is highly indicative of an adolescent sensitive period for threat response regulation. While we highlight literature in support of this unique developmental window, we also emphasize the need for causal studies to clarify the parameters defining such a sensitive period. In doing so, we explore how stress and biological sex affect the development and expression of threat response regulation during adolescence and beyond. Ultimately, a deeper understanding of how these factors interact with and affect developmental trajectories of learning and memory will inform treatment and prevention strategies for pediatric anxiety disorders.
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20
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Carvalho MC, Genaro K, Leite-Panissi CRA, Lovick TA. Influence of estrous cycle stage on acquisition and expression of fear conditioning in female rats. Physiol Behav 2021; 234:113372. [PMID: 33647267 DOI: 10.1016/j.physbeh.2021.113372] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/05/2021] [Accepted: 02/24/2021] [Indexed: 12/29/2022]
Abstract
It is unclear whether all animal models of anxiety-like states developed using males are appropriate for use in females. In females, tests involving a learning component might be influenced not only by estrous cycle stage on the test day but also by the stage during the conditioning process. We used two tests - conditioned freezing (CF) and fear potentiated startle (FPS) to compare responsiveness of male rats and females conditioned and/or tested in proestrus (P) or late diestrus (LD). For CF all rats displayed a similar freezing response regardless of sex or estrous cycle stage. In terms of FPS, males and females conditioned in P and tested in P or LD, and females conditioned in LD and tested in LD all showed potentiated startle. The response waned during the test session in males and in females conditioned in P, but not in those conditioned in LD. In contrast, FPS was not apparent in the first half of the test session in females conditioned in LD and tested in P but developed in the second half. We suggest that fear learning during P and LD is robust but may be initially be obscured in rats tested in P because of generalization to the CS due to high estrogen. Estrous cycle stage is an important consideration which must be taken into account in designing behavioural tests in females.
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Affiliation(s)
- Milene C Carvalho
- Depto Psicologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP 14040-901, Brazil; Instituto de Neurociências e Comportamento, INeC, Ribeirão Preto, SP, Brazil.
| | - Karina Genaro
- Instituto de Neurociências e Comportamento, INeC, Ribeirão Preto, SP, Brazil; Department of Anesthesiology and Postoperative Care, University of California, Irvine, CA, United States
| | - Christie R A Leite-Panissi
- Depto Psicologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP 14040-901, Brazil; Instituto de Neurociências e Comportamento, INeC, Ribeirão Preto, SP, Brazil
| | - Thelma A Lovick
- Instituto de Neurociências e Comportamento, INeC, Ribeirão Preto, SP, Brazil; Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol BS8 1TD, United Kingdom
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21
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Tan SZK, Kim JH. mGlu5: A double-edged sword for aversive learning related therapeutics. NEUROANATOMY AND BEHAVIOUR 2021. [DOI: 10.35430/nab.2021.e16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Aversive memories underlie many types of anxiety disorders. One area of research to more effectively treat anxiety disorders has therefore been identifying pharmacological targets to affect memory processes. Among these targets, the metabotropic glutamate 5 receptor (mGlu5) has received attention due to the availability of drugs to utilize its role in learning and memory. In this review, we highlight preclinical studies examining the role of mGlu5 at various stages of aversive learning and its inhibition via extinction in order to gain a better understanding of its therapeutic potential. We suggest that mGlu5 has distinct roles at different stages of memory that not only makes it a tricky target, but a double-edged sword as a therapeutic. However, the selective involvement of mGlu5 in different memory stages allows for certain precision that could be harnessed clinically. We therefore suggest potential applications, limitations, and pitfalls when considering use of mGlu5 modulators as therapeutics. In addition, we recommend future studies to address important gaps in this literature, such as sex and age factors in light of anxiety disorders being more prevalent in those demographics.
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Affiliation(s)
- Shawn Zheng Kai Tan
- School of Biomedical Science, Li Ka Shing Faculty of Medicine, The University of Hong Kong
- European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Cambridgeshire, United Kingdom
| | - Jee Hyun Kim
- IMPACT – the Institute for Mental and Physical Health and Clinical Translation, School of Medicine, Deakin University, Geelong, VIC, Australia
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22
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Premachandran H, Zhao M, Arruda-Carvalho M. Sex Differences in the Development of the Rodent Corticolimbic System. Front Neurosci 2020; 14:583477. [PMID: 33100964 PMCID: PMC7554619 DOI: 10.3389/fnins.2020.583477] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/01/2020] [Indexed: 12/18/2022] Open
Abstract
In recent years, a growing body of research has shown sex differences in the prevalence and symptomatology of psychopathologies, such as depression, anxiety, and fear-related disorders, all of which show high incidence rates in early life. This has highlighted the importance of including female subjects in animal studies, as well as delineating sex differences in neural processing across development. Of particular interest is the corticolimbic system, comprising the hippocampus, amygdala, and medial prefrontal cortex. In rodents, these corticolimbic regions undergo dynamic changes in early life, and disruption to their normative development is believed to underlie the age and sex-dependent effects of stress on affective processing. In this review, we consolidate research on sex differences in the hippocampus, amygdala, and medial prefrontal cortex across early development. First, we briefly introduce current principles on sexual differentiation of the rodent brain. We then showcase corticolimbic regional sex differences in volume, morphology, synaptic organization, cell proliferation, microglia, and GABAergic signaling, and explain how these differences are influenced by perinatal and pubertal gonadal hormones. In compiling this research, we outline evidence of what and when sex differences emerge in the developing corticolimbic system, and illustrate how temporal dynamics of its maturational trajectory may differ in male and female rodents. This will help provide insight into potential neural mechanisms underlying sex-specific critical windows for stress susceptibility and behavioral emergence.
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Affiliation(s)
| | - Mudi Zhao
- Department of Psychology, University of Toronto Scarborough, Toronto, ON, Canada
| | - Maithe Arruda-Carvalho
- Department of Psychology, University of Toronto Scarborough, Toronto, ON, Canada.,Department of Cell and Systems Biology, University of Toronto Scarborough, Toronto, ON, Canada
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23
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Drzewiecki CM, Willing J, Juraska JM. Influences of age and pubertal status on number and intensity of perineuronal nets in the rat medial prefrontal cortex. Brain Struct Funct 2020; 225:2495-2507. [PMID: 32914251 DOI: 10.1007/s00429-020-02137-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 08/29/2020] [Indexed: 12/20/2022]
Abstract
The prefrontal cortex (PFC) is a late developing region of the cortex, and its protracted maturation during adolescence may confer a period of plasticity. Closure of critical, or sensitive, periods in sensory cortices coincides with perineuronal net (PNN) expression, leading to enhanced inhibitory function and synaptic stabilization. PNN density has been found to increase across adolescence in the male rat medial PFC (mPFC). Here, we examined both male and female rats at four time points spanning adolescent development to stereologically quantify the number and intensity of PNNs in the mPFC. Additionally, because puberty coincides with broad behavioral and neuroanatomical changes, we collected tissue from age-matched pre- and post-pubertal siblings within a litter. Results indicate that both males and females show an increase in the total number and intensity of mPFC PNNs between postnatal day (P) 30 and P60. As we have previously found, white matter under the mPFC also increased at the same time. Male puberty did not affect PNNs, while female pubertal onset led to an abrupt decrease in the total number of PNNs that persisted through mid-adolescence before increasing at P60. Despite the change in PNN number, the intensity of female PNNs was not affected by puberty. Thus, though males and females show increases in mPFC PNNs during adolescence, the pubertal decrease in the number of PNNs in female rats may indicate a difference in the pattern of maximal plasticity between the sexes during adolescence.
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Affiliation(s)
- Carly M Drzewiecki
- Program in Neuroscience, University of Illinois at Urbana-Champaign, Champaign, IL, 61820, USA
| | - Jari Willing
- Department of Psychology, University of Illinois at Urbana-Champaign, 603 E Daniel St, Champaign, IL, 61820, USA.,Department of Psychology, Bowling Green State University, 822 E Merry Ave, Bowling Green, OH, 43403, USA
| | - Janice M Juraska
- Program in Neuroscience, University of Illinois at Urbana-Champaign, Champaign, IL, 61820, USA. .,Department of Psychology, University of Illinois at Urbana-Champaign, 603 E Daniel St, Champaign, IL, 61820, USA.
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24
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Guerin AA, Zbukvic IC, Luikinga SJ, Drummond KD, Lawrence AJ, Madsen HB, Kim JH. Extinction and drug-induced reinstatement of cocaine seeking following self-administration or conditioned place preference in adolescent and adult rats. Dev Psychobiol 2020; 63:125-137. [PMID: 32666555 DOI: 10.1002/dev.22017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/22/2020] [Accepted: 06/23/2020] [Indexed: 12/21/2022]
Abstract
Adolescence marks a particularly vulnerable period to developing substance use disorders, and people who start using drugs in adolescence are more likely to relapse. A limited number of studies have investigated age difference in relapse following re-exposure to the drug after a period of abstinence. Using a cocaine self-administration paradigm, we showed no age difference in acquisition or extinction of self-administration. Interestingly, adolescent rats displayed impaired cocaine-primed reinstatement of cocaine seeking. Using the same dose as that self-administered in the first experiment, we then investigated age differences in acquisition and extinction of conditioned place preference, as well as locomotor sensitization. While there were no differences in locomotor activity or acquisition of preference, adolescents failed to extinguish their preference, even when the number of extinction sessions was doubled from what adults received. Taken together, these results suggest that while cocaine has similar rewarding and reinforcing effects regardless of age, adolescents may attribute stronger salience to the drug-associated context. In addition, re-exposure to cocaine itself may not be a strong relapse trigger in adolescence. Overall, these findings suggest that we should focus more on alleviating drug-context salience compared to re-exposure to substance in order to reduce relapse of drug seeking in adolescents.
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Affiliation(s)
- Alexandre A Guerin
- Mental Health Theme, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia.,Florey Department of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Isabel C Zbukvic
- Mental Health Theme, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia.,Florey Department of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Sophia J Luikinga
- Mental Health Theme, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia.,Florey Department of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Katherine D Drummond
- Mental Health Theme, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia.,Florey Department of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Andrew J Lawrence
- Mental Health Theme, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia.,Florey Department of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Heather B Madsen
- Mental Health Theme, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia.,Florey Department of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Jee Hyun Kim
- Mental Health Theme, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia.,Florey Department of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
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