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Harris LT. The Neuroscience of Human and Artificial Intelligence Presence. Annu Rev Psychol 2024; 75:433-466. [PMID: 37906951 DOI: 10.1146/annurev-psych-013123-123421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Two decades of social neuroscience and neuroeconomics research illustrate the brain mechanisms that are engaged when people consider human beings, often in comparison to considering artificial intelligence (AI) as a nonhuman control. AI as an experimental control preserves agency and facilitates social interactions but lacks a human presence, providing insight into brain mechanisms that are engaged by human presence and the presence of AI. Here, I review this literature to determine how the brain instantiates human and AI presence across social perception and decision-making paradigms commonly used to realize a social context. People behave toward humans differently than they do toward AI. Moreover, brain regions more engaged by humans compared to AI extend beyond the social cognition brain network to all parts of the brain, and the brain sometimes is engaged more by AI than by humans. Finally, I discuss gaps in the literature, limitations in current neuroscience approaches, and how an understanding of the brain correlates of human and AI presence can inform social science in the wild.
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Affiliation(s)
- Lasana T Harris
- Department of Experimental Psychology, University College London, London, United Kingdom;
- Alan Turing Institute, London, United Kingdom
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2
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Takenawa S, Nagasawa Y, Go K, Chérasse Y, Mizuno S, Sano K, Ogawa S. Activity of estrogen receptor β expressing neurons in the medial amygdala regulates preference toward receptive females in male mice. Proc Natl Acad Sci U S A 2023; 120:e2305950120. [PMID: 37819977 PMCID: PMC10589649 DOI: 10.1073/pnas.2305950120] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 09/06/2023] [Indexed: 10/13/2023] Open
Abstract
The processing of information regarding the sex and reproductive state of conspecific individuals is critical for successful reproduction and survival in males. Generally, male mice exhibit a preference toward the odor of sexually receptive (RF) over nonreceptive females (XF) or gonadally intact males (IM). Previous studies suggested the involvement of estrogen receptor beta (ERβ) expressed in the medial amygdala (MeA) in male preference toward RF. To further delineate the role played by ERβ in the MeA in the neuronal network regulating male preference, we developed a new ERβ-iCre mouse line using the CRISPR-Cas9 system. Fiber photometry Ca2+ imaging revealed that ERβ-expressing neurons in the postero-dorsal part of the MeA (MeApd-ERβ+ neurons) were more active during social investigation toward RF compared to copresented XF or IM mice in a preference test. Chemogenetic inhibition of MeApd-ERβ+ neuronal activity abolished a preference to RF in "RF vs. XF," but not "RF vs. IM," tests. Analysis with cre-dependent retrograde tracing viral vectors identified the principal part of the bed nucleus of stria terminalis (BNSTp) as a primary projection site of MeApd-ERβ+ neurons. Fiber photometry recording in the BNSTp during a preference test revealed that chemogenetic inhibition of MeApd-ERβ+ neurons abolished differential neuronal activity of BNSTp cells as well as a preference to RF against XF but not against IM mice. Collectively, these findings demonstrate for the first time that MeApd-ERβ+ neuronal activity is required for expression of receptivity-based preference (i.e., RF vs. XF) but not sex-based preference (i.e., RF vs. IM) in male mice.
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Affiliation(s)
- Satoshi Takenawa
- Laboratory of Behavioral Neuroendocrinology, Faculty of Human Sciences, University of Tsukuba, Tsukuba305-8577, Japan
| | - Yutaro Nagasawa
- Laboratory of Behavioral Neuroendocrinology, Faculty of Human Sciences, University of Tsukuba, Tsukuba305-8577, Japan
| | - Kim Go
- Laboratory of Behavioral Neuroendocrinology, Faculty of Human Sciences, University of Tsukuba, Tsukuba305-8577, Japan
| | - Yoan Chérasse
- International Institute for Integrative Sleep Medicine, University of Tsukuba, Tsukuba305-8575, Japan
| | - Seiya Mizuno
- Laboratory Animal Resource Center and Trans-border Medical Research Center, Institute of Medicine, University of Tsukuba, Tsukuba305-8575, Japan
| | - Kazuhiro Sano
- Laboratory of Behavioral Neuroendocrinology, Faculty of Human Sciences, University of Tsukuba, Tsukuba305-8577, Japan
| | - Sonoko Ogawa
- Laboratory of Behavioral Neuroendocrinology, Faculty of Human Sciences, University of Tsukuba, Tsukuba305-8577, Japan
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3
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Whitten CJ, Hooker MK, Wells AN, Kearney JN, Jenkins MS, Cooper MA. Sex differences in dominance relationships in Syrian hamsters. Physiol Behav 2023; 270:114294. [PMID: 37453726 PMCID: PMC10529893 DOI: 10.1016/j.physbeh.2023.114294] [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: 05/08/2023] [Revised: 06/27/2023] [Accepted: 07/12/2023] [Indexed: 07/18/2023]
Abstract
Dominance relationships are identified by changes in agonistic behavior toward specific individuals. While there are considerable individual and species differences in dominance relationships, sex differences are poorly understood in rodent models because aggression among female rodents is rare. The aim of this study was to characterize sex differences in the formation and maintenance of dominance relationships in same-sex pairs of male and female Syrian hamsters. We pooled data from multiple projects in our lab to evaluate dominance interactions in 68 male dyads and 88 female dyads. In each project, animals were matched with a partner similar in age, sex, and estrous cycle and we exposed animals to daily social encounters for two weeks in a resident-intruder format. We found that female hamsters were quicker to attack and attacked at higher rates compared to males regardless of dominance status. In addition, resident female hamsters were quicker to attack and attacked at higher rates than intruder females, but aggression in males did not depend on residency status. Female subordinates were quicker to submit and fled at higher rates from their dominant counterparts compared to male subordinates. Intruder subordinate females were quicker to submit and fled at higher rates than resident subordinate females. Females were also more resistant than males to becoming subordinate in that they fought back more consistently and were more likely to reverse their dominance status. These findings indicate that dominance relationships are less stable in females compared to males and that residency status has a larger impact on agonistic behavior in females than males. Overall, differences in how males and females display territorial aggression can lead to sex differences in the establishment and maintenance of dominance relationships.
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Affiliation(s)
- Conner J Whitten
- Department of Psychology, The University of Tennessee, Knoxville, USA
| | | | - Ashley N Wells
- Department of Psychology, The University of Tennessee, Knoxville, USA
| | - Jessica N Kearney
- Department of Psychology, The University of Tennessee, Knoxville, USA
| | - Matthew S Jenkins
- Department of Psychology, The University of Tennessee, Knoxville, USA
| | - Matthew A Cooper
- Department of Psychology, The University of Tennessee, Knoxville, USA.
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4
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Lv J, Hua SJ, Wu XF, Ding YJ, Zhang CL, Sun FJ. REMOVED: Antidiuretic hormone associates with the cognitive memory in small-cell lung cancer patients. CURRENT RESEARCH IN BEHAVIORAL SCIENCES 2021. [DOI: 10.1016/j.crbeha.2021.100061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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5
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Modi ME, Sahin M. A unified circuit for social behavior. Neurobiol Learn Mem 2019; 165:106920. [PMID: 30149055 PMCID: PMC6387844 DOI: 10.1016/j.nlm.2018.08.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 08/04/2018] [Accepted: 08/14/2018] [Indexed: 12/23/2022]
Abstract
Recent advances in circuit manipulation technologies have enabled the association of distinct neural circuits with complex social behaviors. The brain areas identified through historical anatomical characterizations as mediators of sexual and parental behaviors can now be functionally linked to adult social behaviors within a unified circuit. In vivo electrophysiology, optogenetics and chemogenetics have been used to follow the processing of social sensory stimuli from perception by the olfactory system to valence detection by the amygdala and mesolimbic dopamine system to integration by the cerebral and cerebellar cortices under modulation of hypothalamic neuropeptides. Further, these techniques have been able to identify the distinct functional changes induced by social as opposed to non-social stimuli. Together this evidence suggests that there is a distinct, functionally coupled circuit that is selectively activated by social stimuli. A unified social circuit provides a new framework against which synaptopathic autism related mutations can be considered and novel pharmacotherapeutic strategies can be developed.
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Affiliation(s)
- Meera E Modi
- Translational Neuroscience Center, F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, United States
| | - Mustafa Sahin
- Translational Neuroscience Center, F.M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, United States.
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Bullmann T, Feneberg E, Kretzschmann TP, Ogunlade V, Holzer M, Arendt T. Hibernation Impairs Odor Discrimination - Implications for Alzheimer's Disease. Front Neuroanat 2019; 13:69. [PMID: 31379517 PMCID: PMC6646461 DOI: 10.3389/fnana.2019.00069] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 06/21/2019] [Indexed: 11/13/2022] Open
Abstract
Reversible formation of PHF-like phosphorylated tau, an early feature of Alzheimer's disease (AD) was previously shown to occur in torpor during hibernation in the Golden hamster (Syrian hamster, Mesocricetus auratus). Here, we tackled the question to what extent hibernating Golden hamsters can serve as a model for the early stage of AD. During early AD, anosmia, the loss of olfactory function, is a common and typical feature. We, thus, investigated tau phosphorylation, synaptic plasticity and behavioral physiology of the olfactory system during hibernation. Tau was phosphorylated on several AD-relevant epitopes, and distribution of PHF-like phosphorylated tau in the olfactory bulb was quite similar to what is seen in AD. Tau phosphorylation was not associated with a destabilization of microtubules and did not lead to fibril formation. Previously, we observed a transient spine reduction in pyramidal cells in the hippocampus, which is correlated with the distribution of phosphorylated tau. Here we show that granule cells in the olfactory bulb are devoid of phosphorylated tau and maintain their spines number during torpor. No reduction of synaptic proteins was observed. However, hibernation did impair the recall performance in a two-odor discrimination task. We conclude that hibernation is associated with a specific olfactory memory deficit, which might not be attributed to the formation of PHF-like phosphorylated tau within the olfactory bulb. We discuss a possible involvement of modulatory input provided by cholinergic neurons in the basal forebrain, which are affected by hibernation.
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Affiliation(s)
- Torsten Bullmann
- Department of Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Emily Feneberg
- Department of Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Tanja Petra Kretzschmann
- Department of Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Vera Ogunlade
- Department of Neuropathology, University of Leipzig, Leipzig, Germany
| | - Max Holzer
- Department of Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | - Thomas Arendt
- Department of Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
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7
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Rao RP, von Heimendahl M, Bahr V, Brecht M. Neuronal Responses to Conspecifics in the Ventral CA1. Cell Rep 2019; 27:3460-3472.e3. [DOI: 10.1016/j.celrep.2019.05.081] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 04/05/2019] [Accepted: 05/21/2019] [Indexed: 12/27/2022] Open
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8
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Weston CSE. Amygdala Represents Diverse Forms of Intangible Knowledge, That Illuminate Social Processing and Major Clinical Disorders. Front Hum Neurosci 2018; 12:336. [PMID: 30186129 PMCID: PMC6113401 DOI: 10.3389/fnhum.2018.00336] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 08/02/2018] [Indexed: 01/21/2023] Open
Abstract
Amygdala is an intensively researched brain structure involved in social processing and multiple major clinical disorders, but its functions are not well understood. The functions of a brain structure are best hypothesized on the basis of neuroanatomical connectivity findings, and of behavioral, neuroimaging, neuropsychological and physiological findings. Among the heaviest neuroanatomical interconnections of amygdala are those with perirhinal cortex (PRC), but these are little considered in the theoretical literature. PRC integrates complex, multimodal, meaningful and fine-grained distributed representations of objects and conspecifics. Consistent with this connectivity, amygdala is hypothesized to contribute meaningful and fine-grained representations of intangible knowledge for integration by PRC. Behavioral, neuroimaging, neuropsychological and physiological findings further support amygdala mediation of a diversity of such representations. These representations include subjective valence, impact, economic value, noxiousness, importance, ingroup membership, social status, popularity, trustworthiness and moral features. Further, the formation of amygdala representations is little understood, and is proposed to be often implemented through embodied cognition mechanisms. The hypothesis builds on earlier work, and makes multiple novel contributions to the literature. It highlights intangible knowledge, which is an influential but insufficiently researched factor in social and other behaviors. It contributes to understanding the heavy but neglected amygdala-PRC interconnections, and the diversity of amygdala-mediated intangible knowledge representations. Amygdala is a social brain region, but it does not represent species-typical social behaviors. A novel proposal to clarify its role is postulated. The hypothesis is also suggested to illuminate amygdala's involvement in several core symptoms of autism spectrum disorder (ASD). Specifically, novel and testable explanations are proposed for the ASD symptoms of disorganized visual scanpaths, apparent social disinterest, preference for concrete cognition, aspects of the disorder's heterogeneity, and impairment in some activities of daily living. Together, the presented hypothesis demonstrates substantial explanatory potential in the neuroscience, social and clinical domains.
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Tsuji C, Tsuji T, Allchorne A, Leng G, Ludwig M. Effects of lateral olfactory tract stimulation on Fos immunoreactivity in vasopressin neurones of the rat piriform cortex. J Neuroendocrinol 2017; 29:e12531. [PMID: 28862781 DOI: 10.1111/jne.12531] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 08/22/2017] [Accepted: 08/28/2017] [Indexed: 11/28/2022]
Abstract
In the main olfactory system, odours are registered at the main olfactory epithelium and are then processed at the main olfactory bulb (MOB) and, subsequently, by the anterior olfactory nucleus (AON), the piriform cortex (PC) and the cortical amygdala. Previously, we reported populations of vasopressin neurones in different areas of the rat olfactory system, including the MOB, accessory olfactory bulb (AOB) and the AON and showed that these are involved in the coding of social odour information. Utilising immunohistochemistry and a transgenic rat in which an enhanced green fluorescent protein reporter gene is expressed in vasopressin neurones (eGFP-vasopressin), we now show a population of vasopressin neurones in the PC. The vasopressin neurones are predominantly located in the layer II of the PC and the majority co-express the excitatory transmitter glutamate. Furthermore, there is no sex difference in the number of neurones expressing vasopressin. Electrical stimulation of the lateral olfactory tract leads to a significant increase in the number of Fos-positive nuclei in the PC, MOB, AOB, dorsal AON and supraoptic nucleus (SON). However, there was only a significant increase in Fos expression in vasopressin cells of the PC and SON. Thus, functionally distinct populations of vasopressin cells are implicated in olfactory processing at multiple stages of the olfactory pathway.
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Affiliation(s)
- C Tsuji
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
| | - T Tsuji
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
| | - A Allchorne
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
| | - G Leng
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
| | - M Ludwig
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh, UK
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10
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Geng CH, Wang C, Yang J, Wang H, Ma RQ, Liu X, Wang CH. Arginine vasopressin improves the memory deficits in Han Chinese patients with first-episode schizophrenia. Peptides 2017; 97:8-15. [PMID: 28882471 DOI: 10.1016/j.peptides.2017.09.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 08/29/2017] [Accepted: 09/02/2017] [Indexed: 11/18/2022]
Abstract
The memory impairment is a core deficit in the first-episode schizophrenia patients. Arginine vasopressin (AVP) in the brain can improve learning and memory. We performed multicentre, randomized, double-blind, placebo-controlled, parallel-group clinical trial to study the cognitive functioning in Han Chinese first-episode schizophrenic patients in a 12-week treatment regime with the intranasal administration of AVP (128 cases) or placebo (131 cases) in addition to the conventional treatment. The methods of positive and negative syndrome scale (PANSS), Wechsler memory scale-4th edition (WMS-IV) and event-related potential (ERP) were used to study the effects of AVP on the cognitive function. The results showed that (1) AVP concentration decreased in cerebrospinal fluid (CSF) of the right-handed Han Chinese first-episode schizophrenic patients comparing with that of the health volunteers (7.1±1.5pg/ml vs 13.3±1.9pg/ml, p<0.01), and did not change in plasma; (2) AVP significantly improved PANSS scores including total scores, positive symptoms, negative symptoms and general psychopathology comparing with those of the placebo group; (3) AVP elevated WMS-IV scores including the long-term memory (accumulation), short-term memory (recognition, comprehension), immediate memory (number recitation) and memory quotient 4, 8 and 12 weeks after treatment; and (4) AVP did not influence the latency and wave amplitude of target stimulus of P300 of right-handed Han Chinese first-episode schizophrenic patients. The data suggested that AVP might improve cognitive process, such as memorizing and extraction of the information although there were many changes of cognitive functions in the right-handed Han Chinese first-episode schizophrenic patients.
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Affiliation(s)
- Cai-Hong Geng
- The Second Affiliated Hospital of Xinxiang Medical University and Henan Province Mental Hospital, Xinxiang, Henan 453002, China
| | - Chao Wang
- The Second Affiliated Hospital of Xinxiang Medical University and Henan Province Mental Hospital, Xinxiang, Henan 453002, China
| | - Jun Yang
- Xinxiang Institute for New Medicine, Xinxing, Henan 453003, China; Xinjiang Hongda Food & Beverage Ltd., Xinjiang, Shanxi 043110, China.
| | - Hua Wang
- Xinxiang Institute for New Medicine, Xinxing, Henan 453003, China; Xinjiang Hongda Food & Beverage Ltd., Xinjiang, Shanxi 043110, China
| | - Rui-Qing Ma
- Xinxiang Institute for New Medicine, Xinxing, Henan 453003, China
| | - Xu Liu
- The Second Affiliated Hospital of Xinxiang Medical University and Henan Province Mental Hospital, Xinxiang, Henan 453002, China
| | - Chang-Hong Wang
- The Second Affiliated Hospital of Xinxiang Medical University and Henan Province Mental Hospital, Xinxiang, Henan 453002, China
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11
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Lorenzi E, Mayer U, Rosa-Salva O, Vallortigara G. Dynamic features of animate motion activate septal and preoptic areas in visually naïve chicks ( Gallus gallus ). Neuroscience 2017; 354:54-68. [DOI: 10.1016/j.neuroscience.2017.04.022] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 03/25/2017] [Accepted: 04/17/2017] [Indexed: 02/03/2023]
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12
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Altered Sensory Code Drives Juvenile-to-Adult Behavioral Maturation in Caenorhabditis elegans. eNeuro 2017; 3:eN-NWR-0175-16. [PMID: 28083560 PMCID: PMC5220224 DOI: 10.1523/eneuro.0175-16.2016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 11/23/2016] [Accepted: 12/03/2016] [Indexed: 11/21/2022] Open
Abstract
Adults perform better than juveniles in food-seeking tasks. Using the nematode Caenorhabditis elegans to probe the neural mechanisms underlying behavioral maturation, we found that adults and juveniles require different combinations of sensory neurons to generate age-specific food-seeking behavior. We first show that adults and juveniles differ in their response to and preference for food-associated odors, and we analyze genetic mutants to map the neuronal circuits required for those behavioral responses. We developed a novel device to trap juveniles and record their neuronal activity. Activity measurements revealed that adult and juvenile AWA sensory neurons respond to the addition of diacetyl stimulus, whereas AWB, ASK, and AWC sensory neurons encode its removal specifically in adults. Further, we show that reducing neurotransmission from the additional AWB, ASK, and AWC sensory neurons transforms odor preferences from an adult to a juvenile-like state. We also show that AWB and ASK neurons drive behavioral changes exclusively in adults, providing more evidence that age-specific circuits drive age-specific behavior. Collectively, our results show that an odor-evoked sensory code is modified during the juvenile-to-adult transition in animal development to drive age-appropriate behavior. We suggest that this altered sensory code specifically enables adults to extract additional stimulus features and generate robust behavior.
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Xie K, Fox GE, Liu J, Lyu C, Lee JC, Kuang H, Jacobs S, Li M, Liu T, Song S, Tsien JZ. Brain Computation Is Organized via Power-of-Two-Based Permutation Logic. Front Syst Neurosci 2016; 10:95. [PMID: 27895562 PMCID: PMC5108790 DOI: 10.3389/fnsys.2016.00095] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 11/07/2016] [Indexed: 11/17/2022] Open
Abstract
There is considerable scientific interest in understanding how cell assemblies—the long-presumed computational motif—are organized so that the brain can generate intelligent cognition and flexible behavior. The Theory of Connectivity proposes that the origin of intelligence is rooted in a power-of-two-based permutation logic (N = 2i–1), producing specific-to-general cell-assembly architecture capable of generating specific perceptions and memories, as well as generalized knowledge and flexible actions. We show that this power-of-two-based permutation logic is widely used in cortical and subcortical circuits across animal species and is conserved for the processing of a variety of cognitive modalities including appetitive, emotional and social information. However, modulatory neurons, such as dopaminergic (DA) neurons, use a simpler logic despite their distinct subtypes. Interestingly, this specific-to-general permutation logic remained largely intact although NMDA receptors—the synaptic switch for learning and memory—were deleted throughout adulthood, suggesting that the logic is developmentally pre-configured. Moreover, this computational logic is implemented in the cortex via combining a random-connectivity strategy in superficial layers 2/3 with nonrandom organizations in deep layers 5/6. This randomness of layers 2/3 cliques—which preferentially encode specific and low-combinatorial features and project inter-cortically—is ideal for maximizing cross-modality novel pattern-extraction, pattern-discrimination and pattern-categorization using sparse code, consequently explaining why it requires hippocampal offline-consolidation. In contrast, the nonrandomness in layers 5/6—which consists of few specific cliques but a higher portion of more general cliques projecting mostly to subcortical systems—is ideal for feedback-control of motivation, emotion, consciousness and behaviors. These observations suggest that the brain’s basic computational algorithm is indeed organized by the power-of-two-based permutation logic. This simple mathematical logic can account for brain computation across the entire evolutionary spectrum, ranging from the simplest neural networks to the most complex.
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Affiliation(s)
- Kun Xie
- Brain and Behavior Discovery Institute and Department of Neurology, Medical College of Georgia, Augusta UniversityAugusta, GA, USA; The Brain Decoding Center, Banna Biomedical Research Institute, Yunnan Academy of Science and TechnologyYunnan, China
| | - Grace E Fox
- Brain and Behavior Discovery Institute and Department of Neurology, Medical College of Georgia, Augusta University Augusta, GA, USA
| | - Jun Liu
- Brain and Behavior Discovery Institute and Department of Neurology, Medical College of Georgia, Augusta UniversityAugusta, GA, USA; The Brain Decoding Center, Banna Biomedical Research Institute, Yunnan Academy of Science and TechnologyYunnan, China
| | - Cheng Lyu
- Department of Computer Science and Brain Imaging Center, University of GeorgiaAthens, GA, USA; School of Automation, Northwestern Polytechnical UniversityXi'an, China
| | - Jason C Lee
- Brain and Behavior Discovery Institute and Department of Neurology, Medical College of Georgia, Augusta University Augusta, GA, USA
| | - Hui Kuang
- Brain and Behavior Discovery Institute and Department of Neurology, Medical College of Georgia, Augusta University Augusta, GA, USA
| | - Stephanie Jacobs
- Brain and Behavior Discovery Institute and Department of Neurology, Medical College of Georgia, Augusta University Augusta, GA, USA
| | - Meng Li
- Brain and Behavior Discovery Institute and Department of Neurology, Medical College of Georgia, Augusta UniversityAugusta, GA, USA; The Brain Decoding Center, Banna Biomedical Research Institute, Yunnan Academy of Science and TechnologyYunnan, China
| | - Tianming Liu
- Department of Computer Science and Brain Imaging Center, University of Georgia Athens, GA, USA
| | - Sen Song
- McGovern Institute for Brain Research and Center for Brain-Inspired Computing Research, Tsinghua University Beijing, China
| | - Joe Z Tsien
- Brain and Behavior Discovery Institute and Department of Neurology, Medical College of Georgia, Augusta UniversityAugusta, GA, USA; The Brain Decoding Center, Banna Biomedical Research Institute, Yunnan Academy of Science and TechnologyYunnan, China
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Ferri SL, Kreibich AS, Torre M, Piccoli CT, Dow H, Pallathra AA, Li H, Bilker WB, Gur RC, Abel T, Brodkin ES. Activation of basolateral amygdala in juvenile C57BL/6J mice during social approach behavior. Neuroscience 2016; 335:184-94. [PMID: 27520082 DOI: 10.1016/j.neuroscience.2016.08.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 07/26/2016] [Accepted: 08/03/2016] [Indexed: 12/26/2022]
Abstract
There is a strong need to better understand the neurobiology of juvenile sociability (tendency to seek social interaction), a phenotype of central relevance to autism spectrum disorders (ASD). Although numerous genetic mouse models of ASD showing reduced sociability have been reported, and certain brain regions, such as the amygdala, have been implicated in sociability, there has been little emphasis on delineating brain structures and circuits activated during social interactions in the critical juvenile period of the mouse strain that serves as the most common genetic background for these models-the highly sociable C57BL/6J (B6) strain. We measured expression of the immediate early genes Fos and Egr-1 to map activation of brain regions following the Social Approach Test (SAT) in juvenile male B6 mice. We hypothesized that juvenile B6 mice would show activation of the amygdala during social interactions. The basolateral amygdala (BLA) was activated by social exposure in highly sociable, 4-week-old B6 mice. In light of these data, and the many lines of evidence indicating alteration of amygdala circuits in human ASD, future studies are warranted to assess structural and functional alterations in the BLA, particularly at BLA synapses, in various mouse models of ASD.
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Affiliation(s)
- Sarah L Ferri
- Department of Biology, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Boulevard, Building 421, Philadelphia, PA 19104-6168, USA
| | - Arati S Kreibich
- Center for Neurobiology and Behavior, Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Translational Research Laboratory, 125 South 31st Street, Room 2220, Philadelphia, PA 19104-3403, USA
| | - Matthew Torre
- Center for Neurobiology and Behavior, Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Translational Research Laboratory, 125 South 31st Street, Room 2220, Philadelphia, PA 19104-3403, USA
| | - Cara T Piccoli
- Center for Neurobiology and Behavior, Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Translational Research Laboratory, 125 South 31st Street, Room 2220, Philadelphia, PA 19104-3403, USA
| | - Holly Dow
- Center for Neurobiology and Behavior, Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Translational Research Laboratory, 125 South 31st Street, Room 2220, Philadelphia, PA 19104-3403, USA
| | - Ashley A Pallathra
- Center for Neurobiology and Behavior, Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Translational Research Laboratory, 125 South 31st Street, Room 2220, Philadelphia, PA 19104-3403, USA
| | - Hongzhe Li
- Department of Biostatistics and Epidemiology, Perelman School of Medicine at the University of Pennsylvania, 215 Blockley Hall, 423 Guardian Drive, Philadelphia, PA 19104-6021, USA
| | - Warren B Bilker
- Department of Biostatistics and Epidemiology, Perelman School of Medicine at the University of Pennsylvania, 215 Blockley Hall, 423 Guardian Drive, Philadelphia, PA 19104-6021, USA
| | - Ruben C Gur
- Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, 10 Gates Pavilion, Philadelphia, PA 19104-4283, USA
| | - Ted Abel
- Department of Biology, University of Pennsylvania, Smilow Center for Translational Research, 3400 Civic Center Boulevard, Building 421, Philadelphia, PA 19104-6168, USA
| | - Edward S Brodkin
- Center for Neurobiology and Behavior, Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Translational Research Laboratory, 125 South 31st Street, Room 2220, Philadelphia, PA 19104-3403, USA.
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Yu WC, Liu CY, Lai WS. Repeated, Intermittent Social Defeat across the Entire Juvenile Period Resulted in Behavioral, Physiological, Hormonal, Immunological, and Neurochemical Alterations in Young Adult Male Golden Hamsters. Front Behav Neurosci 2016; 10:110. [PMID: 27375450 PMCID: PMC4901039 DOI: 10.3389/fnbeh.2016.00110] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 05/23/2016] [Indexed: 12/14/2022] Open
Abstract
The developing brain is vulnerable to social defeat during the juvenile period. As complements of human studies, animal models of social defeat provide a straightforward approach to investigating the functional and neurobiological consequences of social defeats. Taking advantage of agonist behavior and social defeat in male golden hamster, a set of 6 experiments was conducted to investigate the consequences at multiple levels in young adulthood resulting from repeated, intermittent social defeats or “social threats” across the entire juvenile period. Male hamsters at postnatal day 28 (P28) were randomly assigned to either the social defeat, “social threat”, or arena control group, and they correspondingly received a series of nine social interaction trials (i.e., either social defeat, “social threat”, or arena control conditions) from P33 to P66. At the behavioral level (Experiment 1), we found that repeated social defeats (but not “social threats”) significantly impacted locomotor activity in the familiar context and social interaction in the familiar/unfamiliar social contexts. At the physiological and hormonal levels (Experiments 2 and 3), repeated social defeat significantly enhanced the cortisol and norepinephrine concentrations in blood. Enlargement of the spleen was also found in the social defeat and “social threat” groups. At the immunological level (Experiment 4), the social defeat group showed lower levels of pro-inflammatory cytokines in the hypothalamus and hippocampus but higher concentration of IL-6 in the striatum compared to the other two groups. At the neurochemical level (Experiment 5), the socially defeated hamsters mainly displayed reductions of dopamine, dopamine metabolites, and 5-HT levels in the striatum and decreased level of 5-HT in the hippocampus. In Experiment 6, an increase in the spine density of hippocampal CA1 pyramidal neurons was specifically observed in the “social threat” group. Collectively, our findings indicate that repeated, intermittent social defeats throughout entire adolescence in hamsters impact their adult responses at multiple levels. Our results also suggest that the “social threat” group may serve as an appropriate control. This study further suggest that the alterations of behavioral responses and neurobiological functions in the body and brain might provide potential markers to measure the negative consequences of chronic social defeats.
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Affiliation(s)
- Wei-Chun Yu
- Department of Psychology, National Taiwan University Taipei, Taiwan
| | - Ching-Yi Liu
- Department of Psychology, National Taiwan University Taipei, Taiwan
| | - Wen-Sung Lai
- Department of Psychology, National Taiwan UniversityTaipei, Taiwan; Graduate Institute of Brain and Mind Sciences, National Taiwan UniversityTaipei, Taiwan; Neurobiology and Cognitive Science Center, National Taiwan UniversityTaipei, Taiwan
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Social Isolation During Postweaning Development Causes Hypoactivity of Neurons in the Medial Nucleus of the Male Rat Amygdala. Neuropsychopharmacology 2016; 41:1929-40. [PMID: 26677945 PMCID: PMC4869062 DOI: 10.1038/npp.2015.364] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 12/04/2015] [Accepted: 12/11/2015] [Indexed: 12/28/2022]
Abstract
Children exposed to neglect or social deprivation are at heightened risk for psychiatric disorders and abnormal social patterns as adults. There is also evidence that prepubertal neglect in children causes abnormal metabolic activity in several brain regions, including the amygdala area. The medial nucleus of the amygdala (MeA) is a key region for performance of social behaviors and still undergoes maturation during the periadolescent period. As such, the normal development of this region may be disrupted by social deprivation. In rodents, postweaning social isolation causes a range of deficits in sexual and agonistic behaviors that normally rely on the posterior MeA (MeAp). However, little is known about the effects of social isolation on the function of MeA neurons. In this study, we tested whether postweaning social isolation caused abnormal activity of MeA neurons. We found that postweaning social isolation caused a decrease of in vivo firing activity of MeAp neurons, and reduced drive from excitatory afferents. In vitro electrophysiological studies found that postweaning social isolation caused a presynaptic impairment of excitatory input to the dorsal MeAp, but a progressive postsynaptic reduction of membrane excitability in the ventral MeAp. These results demonstrate discrete, subnucleus-specific effects of social deprivation on the physiology of MeAp neurons. This pathophysiology may contribute to the disruption of social behavior after developmental social deprivation, and may be a novel target to facilitate the treatment of social disorders.
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Song Z, Larkin TE, Malley MO, Albers HE. Oxytocin (OT) and arginine-vasopressin (AVP) act on OT receptors and not AVP V1a receptors to enhance social recognition in adult Syrian hamsters (Mesocricetus auratus). Horm Behav 2016; 81:20-7. [PMID: 26975586 DOI: 10.1016/j.yhbeh.2016.02.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 01/24/2016] [Accepted: 02/05/2016] [Indexed: 11/20/2022]
Abstract
Social recognition is a fundamental requirement for all forms of social relationships. A majority of studies investigating the neural mechanisms underlying social recognition in rodents have investigated relatively neutral social stimuli such as juveniles or ovariectomized females over short time intervals (e.g., 2h). The present study developed a new testing model to study social recognition among adult males using a potent social stimulus. Flank gland odors are used extensively in social communication in Syrian hamsters and convey important information such as dominance status. We found that the recognition of flank gland odors after a 3min exposure lasted for at least 24h, substantially longer than the recognition of other social cues in rats and mice. Intracerebroventricular injections of OT and AVP prolonged the recognition of flank gland odor for up to 48h. Selective OTR but not V1aR agonists, mimicked these enhancing effects of OT and AVP. Similarly, selective OTR but not V1aR antagonists blocked recognition of the odors after 20min. In contrast, the recognition of non-social stimuli was not blocked by either the OTR or the V1aR antagonists. Our findings suggest both OT and AVP enhance social recognition via acting on OTRs and not V1aRs and that the recognition enhancing effects of OT and AVP are limited to social stimuli.
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Affiliation(s)
- Zhimin Song
- Neuroscience Institute, Center for Behavioral Neuroscience, Georgia State University, Atlanta, GA, USA
| | - Tony E Larkin
- Neuroscience Institute, Center for Behavioral Neuroscience, Georgia State University, Atlanta, GA, USA
| | - Maureen O' Malley
- Neuroscience Institute, Center for Behavioral Neuroscience, Georgia State University, Atlanta, GA, USA
| | - H Elliott Albers
- Neuroscience Institute, Center for Behavioral Neuroscience, Georgia State University, Atlanta, GA, USA.
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Caldwell HK, Albers HE. Oxytocin, Vasopressin, and the Motivational Forces that Drive Social Behaviors. Curr Top Behav Neurosci 2016; 27:51-103. [PMID: 26472550 DOI: 10.1007/7854_2015_390] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The motivation to engage in social behaviors is influenced by past experience and internal state, but also depends on the behavior of other animals. Across species, the oxytocin (Oxt) and vasopressin (Avp) systems have consistently been linked to the modulation of motivated social behaviors. However, how they interact with other systems, such as the mesolimbic dopamine system, remains understudied. Further, while the neurobiological mechanisms that regulate prosocial/cooperative behaviors have been extensively examined, far less is understood about competitive behaviors, particularly in females. In this chapter, we highlight the specific contributions of Oxt and Avp to several cooperative and competitive behaviors and discuss their relevance to the concept of social motivation across species, including humans. Further, we discuss the implications for neuropsychiatric diseases and suggest future areas of investigation.
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19
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Structural bases for neurophysiological investigations of amygdaloid complex of the brain. Sci Rep 2015; 5:17052. [PMID: 26608527 PMCID: PMC4660295 DOI: 10.1038/srep17052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 10/23/2015] [Indexed: 11/08/2022] Open
Abstract
Amygdala (Am) as a part of limbic system of the brain defines such important functions as adaptive behavior of animals, formation of emotions and memory, regulation of endocrine and visceral functions. We worked out, with the help of mathematic modelling of the pattern recognition theory, principles for organization of neurophysiological and neuromorphological studies of Am nuclei, which take into account the existing heterogeneity of its formations and optimize, to a great extent, the protocol for carrying out of such investigations. The given scheme of studies of Am's structural-functional organization at its highly-informative sections can be used as a guide for precise placement of electrodes', cannulae's and microsensors into particular Am nucleus in the brain with the registration not only the nucleus itself, but also its extensions. This information is also important for defining the number of slices covering specific Am nuclei which must be investigated to reveal the physiological role of a particular part of amygdaloid complex.
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Toor I, Clement D, Carlson EN, Holmes MM. Olfaction and social cognition in eusocial naked mole-rats, Heterocephalus glaber. Anim Behav 2015. [DOI: 10.1016/j.anbehav.2015.06.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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21
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Distribution of the neuronal inputs to the ventral premammillary nucleus of male and female rats. Brain Res 2014; 1582:77-90. [PMID: 25084037 DOI: 10.1016/j.brainres.2014.07.034] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 07/17/2014] [Accepted: 07/22/2014] [Indexed: 02/08/2023]
Abstract
The ventral premammillary nucleus (PMV) expresses dense collections of sex steroid receptors and receptors for metabolic cues, including leptin, insulin and ghrelin. The PMV responds to opposite sex odor stimulation and projects to areas involved in reproductive control, including direct innervation of gonadotropin releasing hormone neurons. Thus, the PMV is well positioned to integrate metabolic and reproductive cues, and control downstream targets that mediate reproductive function. In fact, lesions of PMV neurons blunt female reproductive function and maternal aggression. However, although the projections of PMV neurons have been well documented, little is known about the neuronal inputs received by PMV neurons. To fill this gap, we performed a systematic evaluation of the brain sites innervating the PMV neurons of male and female rats using the retrograde tracer subunit B of the cholera toxin (CTb). In general, we observed that males and females show a similar pattern of afferents. We also noticed that the PMV is preferentially innervated by neurons located in the forebrain, with very few projections coming from brainstem nuclei. The majority of inputs originated from the medial nucleus of the amygdala, the bed nucleus of the stria terminalis and the medial preoptic nucleus. A moderate to high density of afferents was also observed in the ventral subiculum, the arcuate nucleus and the ventrolateral subdivision of the ventromedial nucleus of the hypothalamus. Our findings strengthen the concept that the PMV is part of the vomeronasal system and integrates the brain circuitry controlling reproductive functions.
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Lai WS, Yu WC, Liu CY, Kuo MT, Huang CH. A new method for studying social eavesdropping using male golden hamsters. Physiol Behav 2014; 128:202-11. [DOI: 10.1016/j.physbeh.2014.01.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Revised: 12/03/2013] [Accepted: 01/26/2014] [Indexed: 10/25/2022]
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Martinez LA, Levy MJ, Petrulis A. Endogenous oxytocin is necessary for preferential Fos expression to male odors in the bed nucleus of the stria terminalis in female Syrian hamsters. Horm Behav 2013; 64:653-64. [PMID: 24012945 PMCID: PMC3857696 DOI: 10.1016/j.yhbeh.2013.08.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 08/27/2013] [Accepted: 08/27/2013] [Indexed: 10/26/2022]
Abstract
Successful reproduction in mammals depends on proceptive or solicitational behaviors that enhance the probability of encountering potential mates. In female Syrian hamsters, one such behavior is vaginal scent marking. Recent evidence suggests that the neuropeptide oxytocin (OT) may be critical for regulating this behavior. Blockade of OT receptors in the bed nucleus of the stria terminalis (BNST) or the medial preoptic area (MPOA) decreases vaginal marking responses to male odors; lesion data suggest that BNST, rather than MPOA, mediates this effect. However, how OT interacts with sexual odor processing to drive preferential solicitation is not known. To address this issue, intact female Syrian hamsters were exposed to male or female odors and their brains processed for immunohistochemistry for Fos, a marker of recent neuronal activation, and OT. Additional females were injected intracerebroventricularly (ICV) with an oxytocin receptor antagonist (OTA) or vehicle, and then tested for vaginal marking and Fos responses to sexual odors. Colocalization of OT and Fos in the paraventricular nucleus of the hypothalamus was unchanged following exposure to male odors, but decreased following exposure to female odors. Following injections of OTA, Fos expression to male odors was decreased in BNST, but not in MPOA or the medial amygdala (MA). Fos expression in BNST may be functionally relevant for vaginal marking, given that there was a positive correlation between Fos expression and vaginal marking for BNST, but not MPOA or MA. Together, these data suggest that OT facilitation of neuronal activity in BNST underlies the facilitative effects of OT on solicitational responses to male odors.
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Affiliation(s)
- Luis A Martinez
- Georgia State University, Neuroscience Institute, 100 Piedmont Ave SE, Atlanta, GA 30303, USA.
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24
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Swann JM, Richendrfer HA, Dawson L, Nack E, Whylings J, Garelick T. Exposure to female pheromones stimulates a specific type of neuronal population in the male but not female magnocellular division of the medial preoptic nucleus (MPN mag) of the Syrian hamster. Horm Behav 2013; 64:421-9. [PMID: 23773992 DOI: 10.1016/j.yhbeh.2013.06.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 06/06/2013] [Accepted: 06/10/2013] [Indexed: 11/23/2022]
Abstract
The magnocellular division of the medial preoptic area (MPN mag) integrates pheromonal and hormonal signals to play a critical role in the expression of male typical sex behavior. The MPN mag contains two morphologically distinct neuronal populations; the percentage of each type within the nucleus is sex specific. Males have more neurons with a single nucleolus whereas females have more with multiple nucleoli. To determine which neuronal subtype mediates pheromonal induction of copulation, tissue from male and female hamsters exposed to female pheromones was immunolabeled for the immediate early protein (EGR-1). Subsequently the tissue was counterstained and the number of ERG-1 neurons with one or two nuclei was determined. The results indicate that pheromones stimulate neurons with single nucleoli in males but fail to stimulate either neuronal subtype in females suggesting that synaptic input to the MPN mag is sexually differentiated.
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25
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Portillo W, Antonio-Cabrera E, Camacho FJ, Díaz NF, Paredes RG. Behavioral characterization of non-copulating male mice. Horm Behav 2013; 64:70-80. [PMID: 23673371 DOI: 10.1016/j.yhbeh.2013.05.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 04/30/2013] [Accepted: 05/02/2013] [Indexed: 11/26/2022]
Abstract
Non-copulating (NC) males are those animals that do not mate in spite of repeated testing with sexually receptive females. They have been observed in several species including rats and mice. The present experiment was designed to perform a detailed behavioral characterization of NC male mice. Thus, we evaluated their sexual incentive motivation for a sexually receptive female or a sexually active male, olfactory preference for volatile and non-volatile odors from females or males, and olfactory discrimination between female and male volatile odors and food related odors (milk versus vinegar). We compared the activity of the accessory olfactory system (AOS) in copulating (C) and NC males in response to estrous bedding using the induction of Fos-immunoreactivity (Fos-IR) as a measure of neuronal activation. We also determined if estradiol or dopamine treatment could induce sexual behavior in NC males. Finally, we compared the testis weight and the number of penile spines in C, NC, and gonadectomized males. In the sexual incentive motivation test C males spend significantly more time in the female incentive zone than in the male incentive zone. On the other hand, NC males spend the same amount of time in both incentive zones. In tests of olfactory preference, NC males spent less time investigating estrous odors than C males. As well, NC males discriminate urine from conspecifics but they spend less time smelling these odors than C males. In addition, no increase in Fos expression is observed in NC males when they are exposed to odors from estrous females. Our data also suggest that the deficits observed in NC males are not due to lower circulating levels of gonadal hormones, because estradiol supplementation does not induce sexual behavior in these animals, and their testis weight and the number of penile spines are normal. The results suggest that NC males are not sexually motivated by the receptive females and their odors.
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Affiliation(s)
- W Portillo
- Instituto de Neurobiología Universidad Nacional Autónoma de México, México.
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26
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Lukas M, Toth I, Veenema AH, Neumann ID. Oxytocin mediates rodent social memory within the lateral septum and the medial amygdala depending on the relevance of the social stimulus: male juvenile versus female adult conspecifics. Psychoneuroendocrinology 2013; 38:916-26. [PMID: 23102690 DOI: 10.1016/j.psyneuen.2012.09.018] [Citation(s) in RCA: 142] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 09/24/2012] [Accepted: 09/25/2012] [Indexed: 11/26/2022]
Abstract
Brain oxytocin (OXT) plays an important role in short-term social memory in laboratory rodents. Here we monitored local release of OXT and its functional involvement in the maintenance and retrieval of social memory during the social discrimination test. We further assessed, if the local effects of OXT within the medial amygdala (MeA) and lateral septum (LS) on social discrimination abilities were dependent on the biological relevance of the social stimulus, thus comparing male juvenile versus adult female conspecifics. OXT release was increased in the LS of male rats during the retrieval, but not during the acquisition or maintenance, of social memory for male juvenile stimuli. Blockade of OXT activity by intracerebroventricular (ICV) administration of a specific OXT receptor antagonist (OXTR-A, rats: 0.75 μg/5 μl, mice: 2 μg/2 μl) immediately after acquisition of social memory impaired the maintenance of social memory, and consequently discrimination abilities during retrieval of social memory. In contrast, ICV OXTR-A was without effect when administered 20 min prior to retrieval of social memory in both species. Non-social memory measured in the object discrimination test was not affected by ICV OXTR-A in male mice, indicating that brain OXT is mainly required for memory formation in a social context. The biological relevance of the social stimulus seems to importantly determine social memory abilities, as male rats recognized a previously encountered female adult stimulus for at least 2h (versus 60 min for male juveniles), with a region-dependent contribution of endogenous OXT; while bilateral administration of OXTR-A into the MeA (0.1 μg/1 μl) impaired social memory for adult females only, administration of OXTR-A into the LS via retrodialysis (10 μg/ml, 1.0 μl/min) impaired social memory for both male juveniles and female adults. Overall, these results indicate that brain OXT is a critical mediator of social memory in male rodents and that, depending on the biological relevance of the social stimulus, distinct brain regions are recruited to mediate its effects.
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Affiliation(s)
- Michael Lukas
- Department of Behavioral and Molecular Neurobiology, University of Regensburg, 93053 Regensburg, Germany
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Martinez LA, Petrulis A. The medial preoptic area is necessary for sexual odor preference, but not sexual solicitation, in female Syrian hamsters. Horm Behav 2013; 63:606-14. [PMID: 23415835 PMCID: PMC3633686 DOI: 10.1016/j.yhbeh.2013.02.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 01/28/2013] [Accepted: 02/01/2013] [Indexed: 11/16/2022]
Abstract
Precopulatory behaviors that are preferentially directed towards opposite-sex conspecifics are critical for successful reproduction, particularly in species wherein the sexes live in isolation, such as Syrian hamsters (Mesocricetus auratus). In females, these behaviors include sexual odor preference and vaginal scent marking. The neural regulation of precopulatory behaviors is thought to involve a network of forebrain areas that includes the medial amygdala (MA), the bed nucleus of the stria terminalis (BNST), and the medial preoptic area (MPOA). Although MA and BNST are necessary for sexual odor preference and preferential vaginal marking to male odors, respectively, the role of MPOA in odor-guided female precopulatory behaviors is not well understood. To address this issue, female Syrian hamsters with bilateral, excitotoxic lesions of MPOA (MPOA-X) or sham lesions (SHAM) were tested for sexual odor investigation, scent marking, and lordosis. MPOA-X females did not investigate male odors more than female odors in an odor preference test, indicating that MPOA may be necessary for normal sexual odor preference in female hamsters. This loss of preference cannot be attributed to a sensory deficit, since MPOA-X females successfully discriminated male odors from female odors during an odor discrimination test. Surprisingly, no deficits in vaginal scent marking were observed in MPOA-X females, although these females did exhibit decreased overall levels of flank marking compared to SHAM females. Finally, all MPOA-X females exhibited lordosis appropriately. These results suggest that MPOA plays a critical role in the neural regulation of certain aspects of odor-guided precopulatory behaviors in female Syrian hamsters.
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Affiliation(s)
- Luis A Martinez
- Georgia State University, Neuroscience Institute, 100 Piedmont Ave SE, Atlanta, GA 30303, USA.
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Abstract
Adolescent maturation of responses to social stimuli is essential for adult-typical sociosexual behavior. Naturally occurring developmental changes in male Syrian hamster responses to a salient social cue, female hamster vaginal secretions (VS), provide a good model system for investigating neuroendocrine mechanisms of adolescent change in social reward. Sexually naïve adult, but not juvenile, males show a conditioned place preference (CPP) to VS, indicating that VS is not rewarding before puberty. In this series of experiments, the authors examined the roles of testosterone and dopamine receptor activation in mediating the adolescent gain in positive valence of VS. Experiment 1 showed that testosterone replacement is necessary for gonadectomized adult hamsters to form a CPP to VS. Experiment 2 showed that testosterone treatment is sufficient for juvenile hamsters to form a CPP to VS, and that the dopamine receptor antagonist haloperidol blocks formation of a CPP to VS in these animals. Experiments 3 and 4 demonstrated that the disruption of VS CPP with low doses of haloperidol is the result of a reduction in the attractive properties of VS and not attributable to aversive properties of haloperidol. Together, these studies demonstrate that the unconditioned rewarding properties of a social cue necessary for successful adult sociosexual interactions come about as the result of the pubertal increase in circulating testosterone in male hamsters. Furthermore, this social reward can be prevented by dopamine receptor antagonism, indicating that hypothalamic and/or mesocorticolimbic dopaminergic circuits are targets for hormonal activation of social reward.
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Affiliation(s)
- Margaret R Bell
- University of Texas at Austin, College of Pharmacy, 2701 Speedway A2500, Austin, TX 78712, USA.
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Sano K, Tsuda MC, Musatov S, Sakamoto T, Ogawa S. Differential effects of site-specific knockdown of estrogen receptor α in the medial amygdala, medial pre-optic area, and ventromedial nucleus of the hypothalamus on sexual and aggressive behavior of male mice. Eur J Neurosci 2013; 37:1308-19. [PMID: 23347260 DOI: 10.1111/ejn.12131] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 12/11/2012] [Accepted: 12/17/2012] [Indexed: 10/27/2022]
Abstract
Testosterone is known to play an important role in the regulation of male-type sexual and aggressive behavior. As an aromatised metabolite of testosterone, estradiol-induced activation of estrogen receptor α (ERα) may be crucial for the induction of these behaviors in male mice. However, the importance of ERα expressed in different nuclei for this facilitatory action of testosterone has not been determined. To investigate this issue, we generated an adeno-associated virus vector expressing a small hairpin RNA targeting ERα to site-specifically knockdown ERα expression. We stereotaxically injected either a control or ERα targeting vector into the medial amygdala, medial pre-optic area (MPOA), or ventromedial nucleus of the hypothalamus (VMN) in gonadally intact male mice. Two weeks after injection, all mice were tested biweekly for sexual and aggressive behavior, alternating between behavior tests each week. We found that suppressing ERα in the MPOA reduced sexual but not aggressive behavior, whereas in the VMN it reduced both behaviors. Knockdown of ERα in the medial amygdala did not alter either behavior. Additionally, it was found that ERα knockdown in the MPOA caused a parallel reduction in the number of neuronal nitric oxide synthase-expressing cells. Taken together, these results indicate that the testosterone facilitatory action on male sexual behavior requires the expression of ERα in both the MPOA and VMN, whereas the testosterone facilitatory action on aggression requires the expression of ERα in only the VMN.
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Affiliation(s)
- Kazuhiro Sano
- Laboratory of Behavioral Neuroendocrinology, University of Tsukuba, Tsukuba, Ibaraki, Japan
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Bell MR, De Lorme KC, Figueira RJ, Kashy DA, Sisk CL. Adolescent gain in positive valence of a socially relevant stimulus: engagement of the mesocorticolimbic reward circuitry. Eur J Neurosci 2012; 37:457-68. [PMID: 23173754 DOI: 10.1111/ejn.12058] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Revised: 10/12/2012] [Accepted: 10/16/2012] [Indexed: 01/01/2023]
Abstract
A successful transition from childhood to adulthood requires adolescent maturation of social information processing. The neurobiological underpinnings of this maturational process remain elusive. This research employed the male Syrian hamster as a tractable animal model for investigating the neural circuitry involved in this critical transition. In this species, adult and juvenile males display different behavioral and neural responses to vaginal secretions, which contain pheromones essential for expression of sexual behavior in adulthood. These studies tested the hypothesis that vaginal secretions acquire positive valence over adolescent development via remodeling of neural circuits underlying sexual reward. Sexually naïve adult, but not juvenile, hamsters showed a conditioned place preference for vaginal secretions. Differences in behavioral response to vaginal secretions between juveniles and adults correlated with a difference in the vaginal secretion-induced neural activation pattern in mesocorticolimbic reward circuitry. Fos immunoreactivity increased in response to vaginal secretions in the medial amygdala and ventral tegmental dopaminergic cells of both juvenile and adult males. However, only in adults was there a Fos response to vaginal secretions in non-dopaminergic cells in interfascicular ventral tegmental area, nucleus accumbens core and infralimbic medial prefrontal cortex. These results demonstrate that a socially relevant chemosensory stimulus acquires the status of an unconditioned reward during adolescence, and that this adolescent gain in social reward is correlated with experience-independent engagement of specific cell groups in reward circuitry.
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Affiliation(s)
- Margaret R Bell
- Neuroscience Program, Michigan State University, East Lansing, MI, USA.
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Keller M, Lévy F. The main but not the accessory olfactory system is involved in the processing of socially relevant chemosignals in ungulates. Front Neuroanat 2012; 6:39. [PMID: 23049501 PMCID: PMC3446679 DOI: 10.3389/fnana.2012.00039] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Accepted: 08/30/2012] [Indexed: 12/14/2022] Open
Abstract
Ungulates like sheep and goats have, like many other mammalian species, two complementary olfactory systems. The relative role played by these two systems has long been of interest regarding the sensory control of social behavior. The study of ungulate social behavior could represent a complimentary alternative to rodent studies because they live in a more natural environment and their social behaviors depend heavily on olfaction. In addition, the relative size of the main olfactory bulb (MOB) [in comparison to the accessory olfactory bulb (AOB)] is more developed than in many other lissencephalic species like rodents. In this review, we present data showing a clear involvement of the main olfactory system in two well-characterized social situations under olfactory control in ungulates, namely maternal behavior and offspring recognition at birth and the reactivation of the gonadotropic axis of females exposed to males during the anestrous season. In conclusion, we discuss the apparent discrepancy between the absence of evidence for a role of the vomeronasal system in ungulate social behavior and the existence of a developed accessory olfactory system in these species.
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Affiliation(s)
- Matthieu Keller
- INRA, UMR 85 Physiologie de la Reproduction et des Comportements Nouzilly, France ; CNRS, UMR 7247 Physiologie de la Reproduction et des Comportements Nouzilly, France ; Université François Rabelais de Tours Tours, France
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Low doses of 17β-estradiol rapidly improve learning and increase hippocampal dendritic spines. Neuropsychopharmacology 2012; 37:2299-309. [PMID: 22669167 PMCID: PMC3422494 DOI: 10.1038/npp.2012.82] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
While a great deal of research has been performed on the long-term genomic actions of estrogens, their rapid effects and implications for learning and memory are less well characterized. The often conflicting results of estrogenic effects on learning and memory may be due to complex and little understood interactions between genomic and rapid effects. Here, we investigated the effects of low, physiologically relevant, doses of 17β-estradiol on three different learning paradigms that assess social and non-social aspects of recognition memory and spatial memory, during a transcription independent period of memory maintenance. Ovariectomized female CD1 mice were subcutaneously administered vehicle, 1.5 μg/kg, 2 μg/kg, or 3 μg/kg of 17β-estradiol 15 minutes before social recognition, object recognition, or object placement learning. These paradigms were designed to allow the testing of learning effects within 40 min of hormone administration. In addition, using a different set of ovariectomized mice, we examined the rapid effects of 1.5 μg/kg, 2 μg/kg, or 3 μg/kg of 17β-estradiol on CA1 hippocampal dendritic spines. All 17β-estradiol doses tested impacted learning, memory, and CA1 hippocampal spines. 17β-Estradiol improved both social and object recognition, and may facilitate object placement learning and memory. In addition, 17β-estradiol increased dendritic spine density in the stratum radiatum subregion of the CA1 hippocampus, but did not affect dendritic spines in the lacunosum-moleculare, within 40 min of administration. These results demonstrate that the rapid actions of 17β-estradiol have important implications for general learning and memory processes that are not specific for a particular type of learning paradigm. These effects may be mediated by the rapid formation of new dendritic spines in the hippocampus.
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Pardo-Bellver C, Cádiz-Moretti B, Novejarque A, Martínez-García F, Lanuza E. Differential efferent projections of the anterior, posteroventral, and posterodorsal subdivisions of the medial amygdala in mice. Front Neuroanat 2012; 6:33. [PMID: 22933993 PMCID: PMC3423790 DOI: 10.3389/fnana.2012.00033] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Accepted: 07/27/2012] [Indexed: 11/29/2022] Open
Abstract
The medial amygdaloid nucleus (Me) is a key structure in the control of sociosexual behavior in mice. It receives direct projections from the main and accessory olfactory bulbs (AOB), as well as an important hormonal input. To better understand its behavioral role, in this work we investigate the structures receiving information from the Me, by analysing the efferent projections from its anterior (MeA), posterodorsal (MePD) and posteroventral (MePV) subdivisions, using anterograde neuronal tracing with biotinylated and tetrametylrhodamine-conjugated dextranamines. The Me is strongly interconnected with the rest of the chemosensory amygdala, but shows only moderate projections to the central nucleus and light projections to the associative nuclei of the basolateral amygdaloid complex. In addition, the MeA originates a strong feedback projection to the deep mitral cell layer of the AOB, whereas the MePV projects to its granule cell layer. The Me (especially the MeA) has also moderate projections to different olfactory structures, including the piriform cortex (Pir). The densest outputs of the Me target the bed nucleus of the stria terminalis (BST) and the hypothalamus. The MeA and MePV project to key structures of the circuit involved in the defensive response against predators (medial posterointermediate BST, anterior hypothalamic area, dorsomedial aspect of the ventromedial hypothalamic nucleus), although less dense projections also innervate reproductive-related nuclei. In contrast, the MePD projects mainly to structures that control reproductive behaviors [medial posteromedial BST, medial preoptic nucleus, and ventrolateral aspect of the ventromedial hypothalamic nucleus], although less dense projections to defensive-related nuclei also exist. These results confirm and extend previous results in other rodents and suggest that the medial amygdala is anatomically and functionally compartmentalized.
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Affiliation(s)
- Cecília Pardo-Bellver
- Facultat de Ciències Biològiques, Laboratory of Functional and Comparative Neuroanatomy, Departament de Biologia Cel·lular, Universitat de València València, Spain
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34
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Pubertal testosterone organizes regional volume and neuronal number within the medial amygdala of adult male Syrian hamsters. Brain Res 2012; 1460:33-40. [PMID: 22578470 DOI: 10.1016/j.brainres.2012.04.035] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Revised: 03/19/2012] [Accepted: 04/19/2012] [Indexed: 01/30/2023]
Abstract
The medial amygdala plays a key role in regulating adult social behavior and undergoes structural changes during puberty that may be driven by gonadal hormone secretion during this developmental period. The current study sought to investigate potential organizational effects of testosterone during puberty, activational effects of testosterone in adulthood, and any interactions on regional volume and neuronal number of the medial amygdala. Male Syrian hamsters either did or did not experience endogenous testosterone during pubertal brain development, and then received either testosterone-filled or blank capsules during adulthood 2 weeks before tissue collection. The results show that pubertal testosterone has long-term organizational effects on volume of specific subregions of the medial amygdala such that the presence of pubertal testosterone resulted in 1) decreased volume of the anterior ventral amygdala and, to a lesser extent, the anterior dorsal medial amygdala; and 2) increased volume of the posterior dorsal medial amygdala. Both effects were independent of the presence of testosterone during adulthood. Pubertal testosterone also decreased neuronal number in the anterior dorsal medial amygdala, suggesting a possible mechanism by which pubertal testosterone decreases volume in this subregion. In addition, there was a significant interaction between pubertal and adult testosterone, such that testosterone in adulthood increased the number of neurons in the posterior ventral medial amygdala only in males that did not experience endogenous pubertal testosterone. In conclusion, pubertal testosterone organizes the medial amygdala in a subregion-specific manner, which may contribute to the maturation of adult-typical social behavior.
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van Goethem NP, Rutten K, van der Staay FJ, Jans LAW, Akkerman S, Steinbusch HWM, Blokland A, van't Klooster J, Prickaerts J. Object recognition testing: rodent species, strains, housing conditions, and estrous cycle. Behav Brain Res 2012; 232:323-34. [PMID: 22481082 DOI: 10.1016/j.bbr.2012.03.023] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 03/14/2012] [Accepted: 03/18/2012] [Indexed: 11/28/2022]
Abstract
The object recognition task (ORT) allows assessing learning and memory processes in rodents. In this study, two areas in which knowledge about the ORT could be extended were addressed; i.e. generality to species and strains, and intervening variables including housing and estrous cycle. Regarding generality to species and strains, the ORT performance of golden hamsters was assessed. The hamsters showed sufficient exploration times, object recognition performance, and a retention-interval dependent decline similar to rats and mice. Subsequently, we tested three mouse strains which have not been described before in the ORT; i.e. OF1, NMRI, and SJL mice. OF1 and NMRI strains performed equally well, whereas the SJL strain showed low exploration times and no memory retention. Therefore, the SJL strain is unsuited for ORT experiments using a 1h retention interval and a fixed (3 min) trial duration. Furthermore, the sensitivity to a pharmacological memory deficit model (scopolamine) was tested in three rat strains. Each strain showed a dose dependent relationship, but the least effective dose of scopolamine differed among the three strains, the effect being greater in the order of Wistar, Long-Evans, Hooded Lister rats. Finally, to investigate potential intervening variables in the ORT, the effects of housing conditions and estrous cycle were investigated with rats. Single housing resulted in absolute higher performance than social housing. Furthermore, females in pro-estrus/estrus showed better performance compared to females in met-estrus/di-estrus. Taken together, object recognition appears to be a common ability of rodent species, but different strains have different memory capacities and sensitivities to scopolamine, individual housing leads to higher performance, and performance of females is dependent on the estrous cycle phase. Thus, rodent species, strain, housing, and estrous cycle should be taken into consideration in ORT studies.
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Affiliation(s)
- Nick P van Goethem
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience-MHeNS, European Graduate School of Neuroscience-EURON, Maastricht University, Maastricht, The Netherlands
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36
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Arendt DH, Smith JP, Bastida CC, Prasad MS, Oliver KD, Eyster KM, Summers TR, Delville Y, Summers CH. Contrasting hippocampal and amygdalar expression of genes related to neural plasticity during escape from social aggression. Physiol Behav 2012; 107:670-9. [PMID: 22450262 DOI: 10.1016/j.physbeh.2012.03.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 03/01/2012] [Accepted: 03/05/2012] [Indexed: 01/03/2023]
Abstract
Social subjugation has widespread consequences affecting behavior and underlying neural systems. We hypothesized that individual differences in stress responsiveness were associated with differential expression of neurotrophin associated genes within the hippocampus and amygdala. To do this we examined the brains of hamsters placed in resident/intruder interactions, modified by the opportunity to escape from aggression. In the amygdala, aggressive social interaction stimulated increased BDNF receptor TrK(B) mRNA levels regardless of the ability to escape the aggressor. In contrast, the availability of escape limited the elevation of GluR(1) AMPA subunit mRNA. In the hippocampal CA(1), the glucocorticoid stress hormone, cortisol, was negatively correlated with BDNF and TrK(B) gene expression, but showed a positive correlation with BDNF expression in the DG. Latency to escape the aggressor was also negatively correlated with CA(1) BDNF expression. In contrast, the relationship between amygdalar TrK(B) and GluR(1) was positive with respect to escape latency. These results suggest that an interplay of stress and neurotrophic systems influences learned escape behavior. Animals which escape faster seem to have a more robust neurotrophic profile in the hippocampus, with the opposite of this pattern in the amygdala. We propose that changes in the equilibrium of hippocampal and amygdalar learning result in differing behavioral stress coping choices.
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Affiliation(s)
- David H Arendt
- Department of Biology, University of South Dakota, Vermillion, SD 57069, USA
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37
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O'Connell LA, Hofmann HA. The vertebrate mesolimbic reward system and social behavior network: a comparative synthesis. J Comp Neurol 2012; 519:3599-639. [PMID: 21800319 DOI: 10.1002/cne.22735] [Citation(s) in RCA: 693] [Impact Index Per Article: 57.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
All animals evaluate the salience of external stimuli and integrate them with internal physiological information into adaptive behavior. Natural and sexual selection impinge on these processes, yet our understanding of behavioral decision-making mechanisms and their evolution is still very limited. Insights from mammals indicate that two neural circuits are of crucial importance in this context: the social behavior network and the mesolimbic reward system. Here we review evidence from neurochemical, tract-tracing, developmental, and functional lesion/stimulation studies that delineates homology relationships for most of the nodes of these two circuits across the five major vertebrate lineages: mammals, birds, reptiles, amphibians, and teleost fish. We provide for the first time a comprehensive comparative analysis of the two neural circuits and conclude that they were already present in early vertebrates. We also propose that these circuits form a larger social decision-making (SDM) network that regulates adaptive behavior. Our synthesis thus provides an important foundation for understanding the evolution of the neural mechanisms underlying reward processing and behavioral regulation.
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Affiliation(s)
- Lauren A O'Connell
- Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, Texas 78712, USA
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Albers HE. The regulation of social recognition, social communication and aggression: vasopressin in the social behavior neural network. Horm Behav 2012; 61:283-92. [PMID: 22079778 DOI: 10.1016/j.yhbeh.2011.10.007] [Citation(s) in RCA: 205] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Revised: 10/28/2011] [Accepted: 10/29/2011] [Indexed: 10/15/2022]
Abstract
Neuropeptides in the arginine vasotocin/arginine vasopressin (AVT/AVP) family play a major role in the regulation of social behavior by their actions in the brain. In mammals, AVP is found within a circuit of recriprocally connected limbic structures that form the social behavior neural network. This review examines the role played by AVP within this network in controlling social processes that are critical for the formation and maintenance of social relationships: social recognition, social communication and aggression. Studies in a number of mammalian species indicate that AVP and AVP V1a receptors are ideally suited to regulate the expression of social processes because of their plasticity in response to factors that influence social behavior. The pattern of AVP innervation and V1a receptors across the social behavior neural network may determine the potential range and intensity of social responses that individuals display in different social situations. Although fundamental information on how social behavior is wired in the brain is still lacking, it is clear that different social behaviors can be influenced by the actions of AVP in the same region of the network and that AVP can act within multiple regions of this network to regulate the expression of individual social behaviors. The existing data suggest that AVP can influence social behavior by modulating the interpretation of sensory information, by influencing decision making and by triggering complex motor outputs. This article is part of a Special Issue entitled Oxytocin, Vasopressin, and Social Behavior.
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Affiliation(s)
- H Elliott Albers
- Center for Behavioral Neuroscience, Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA.
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39
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von Heimendahl M, Rao RP, Brecht M. Weak and nondiscriminative responses to conspecifics in the rat hippocampus. J Neurosci 2012; 32:2129-41. [PMID: 22323725 PMCID: PMC6621688 DOI: 10.1523/jneurosci.3812-11.2012] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Revised: 11/23/2011] [Accepted: 12/04/2011] [Indexed: 12/20/2022] Open
Abstract
Little is known about how hippocampal neurons in rodents respond to and represent conspecifics. To address this question, we let rats interact while quantifying hippocampal neuronal activation patterns with extracellular recordings and immediate-early gene (c-Fos) expression. A total of 319 single putative pyramidal neurons was recorded in dorsal hippocampus. In sessions with multiple stimulus rats, no cell responded differentially to individual rats (N = 267 cells). We did find, however, that the presence of other rats induced a significant enhancement or suppression of firing in a fraction of neurons (n = 22 of 319; 7%). As expected, a large fraction of neurons (n = 170; 53%) had place fields. There was no evidence for place-independent responses to rats. Rather, the modulations were linked to the spatial responses. While neurons did not discriminate between individual rats, they did discriminate between rats and inanimate objects. Surprisingly, neuronal responses were more strongly modulated by objects than by rats, even though subjects spent more time near their conspecifics. Consistent with the low fraction of rat-modulated cells, social encounters did not induce c-Fos expression in the hippocampus, while there was a social interaction-specific expression in the basolateral amygdala. In both interacting and non-interacting rats, the fraction of c-Fos-expressing cells in the hippocampus was very low. Our investigation of social coding in the rat hippocampus, along with other recent work, showed that social responses were rare and lacked individual specificity, altogether speaking against a role of rodent dorsal hippocampus in social memory.
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Affiliation(s)
- Moritz von Heimendahl
- Bernstein Center for Computational Neuroscience, Humboldt University of Berlin, 10115 Berlin, Germany
| | - Rajnish P. Rao
- Bernstein Center for Computational Neuroscience, Humboldt University of Berlin, 10115 Berlin, Germany
| | - Michael Brecht
- Bernstein Center for Computational Neuroscience, Humboldt University of Berlin, 10115 Berlin, Germany
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40
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Martinez LA, Petrulis A. The bed nucleus of the stria terminalis is critical for sexual solicitation, but not for opposite-sex odor preference, in female Syrian hamsters. Horm Behav 2011; 60:651-9. [PMID: 21925504 PMCID: PMC3210388 DOI: 10.1016/j.yhbeh.2011.08.018] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Revised: 08/17/2011] [Accepted: 08/24/2011] [Indexed: 10/17/2022]
Abstract
Successful reproduction in vertebrates depends critically upon a suite of precopulatory behaviors that occur prior to mating. In Syrian hamsters (Mesocricetus auratus), these behaviors include vaginal scent marking and preferential investigation of male odors. The neural regulation of vaginal marking and opposite-sex odor preference likely involves an interconnected set of steroid-sensitive nuclei that includes the medial amygdala (MA), the bed nucleus of the stria terminalis (BNST), and the medial preoptic area (MPOA). For example, lesions of MA eliminate opposite-sex odor preference and reduce overall levels of vaginal marking, whereas lesions of MPOA decrease vaginal marking in response to male odors. Although BNST is densely interconnected with both MA and MPOA, little is known about the role of BNST in female precopulatory behaviors. To address this question, females received either bilateral, excitotoxic lesions of BNST (BNST-X) or sham lesions (SHAM), and were tested for scent marking and for investigatory responses to male and female odors. Whereas SHAM females vaginal marked more to male odors than female odors on two days of the estrous cycle, BNST-X females marked at equivalent levels to both odors. This deficit is not due to alterations in social odor investigation, as both BNST-X and SHAM females investigated male odors more than female odors. Finally, BNST lesions did not generally disrupt the cyclic changes in reproductive behaviors that occur across the estrous cycle. Taken together, these results demonstrate that BNST is critical for the normal expression of solicitational behaviors by females in response to male odor stimuli.
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Affiliation(s)
- Luis A Martinez
- Georgia State University, Neuroscience Institute, 100 Piedmont Ave SE, Atlanta, GA 30303, USA.
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41
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Carrillo M, Ricci LA, Melloni RH. Glutamate-vasopressin interactions and the neurobiology of anabolic steroid-induced offensive aggression. Neuroscience 2011; 185:85-96. [PMID: 21459130 DOI: 10.1016/j.neuroscience.2011.03.056] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 02/16/2011] [Accepted: 03/24/2011] [Indexed: 01/10/2023]
Abstract
In the latero-anterior hypothalamus (LAH) increased glutamate and vasopressin (AVP) activity facilitate anabolic androgenic steroid (AAS)-induced offensive aggression. In addition, adolescent AAS treatment increases the strength of glutamate-mediated connections between the LAH and the brain nucleus of stria terminalis (BNST). The current set of studies used male Syrian hamsters exposed to AAS during adolescence to examine whether increased glutamate-mediated stimulation of the BNST is dependent on LAH-AVP signaling and whether this neural pathway modulates adolescent AAS-induced offensive aggression. In the first set of AAS-treated animals offensive aggression was measured following blockade of glutamate activity within the BNST using NBQX. Then, in a second group of AAS-treated animals aggression levels were examined following simultaneous blockade of LAH-AVP activity using Manning compound and stimulation of BNST glutamate using AMPA. Lastly, the number of AVP fibers in apposition to glutamate cells was examined in AAS and control animals, using double-label immunofluorescence. The results showed that administration of NBQX into the BNST dose-dependently reduced aggressive behavior in AAS-treated animals. Further, the current results replicated previous findings showing that blockade of LAH-AVP significantly reduces aggressive behavior in AAS-treated animals. In these animals stimulation of BNST-AMPA receptors had a linear effect on aggression, where the smallest dose exacerbated the inhibitory effect of the V1a antagonist, the medium dose had no effect and the highest dose recuperated aggression to control levels. Finally when compared with control animals, AAS treatment produced a significant increase in the number of AVP fibers in apposition to LAH-glutamate cells. Overall, these results identify the BNST as a key brain region involved in aggression control and provide strong evidence suggesting that AVPergic-mediated stimulation of BNST-glutamate is a possible mechanism that facilitates aggression expression in adolescent AAS-treated animals.
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Affiliation(s)
- M Carrillo
- Behavioral Neuroscience Program, Department of Psychology, 125 Nightingale Hall, Northeastern University, 360 Huntington Avenue, Boston, MA 02155, USA
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42
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Adkins-Regan E. Neuroendocrine contributions to sexual partner preference in birds. Front Neuroendocrinol 2011; 32:155-63. [PMID: 21277320 DOI: 10.1016/j.yfrne.2011.01.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Revised: 01/13/2011] [Accepted: 01/23/2011] [Indexed: 10/18/2022]
Abstract
A majority of birds are socially monogamous, providing exceptional opportunities to discover neuroendocrine mechanisms underlying preferences for opposite-sex partners where the sexes form extended affiliative relationships. Zebra finches have been the focus of the most systematic program of research to date in any socially monogamous animal. In this species, sexual partner preference can be partially or largely sex reversed with hormone manipulations during early development, suggesting a role for organizational hormone actions. This same conclusion emerges from research with Japanese quail, which do not form long-term pairs. In zebra finches, social experience manipulations during juvenile development also can sex reverse partner preference, either alone or in combination with an early hormone manipulation. Although there are several candidate brain regions where neural mechanisms could underlie these effects of hormones or social experience, the necessary research has not yet been done to determine their involvement. The neuroendocrinology of avian sexual partner preference is still frontier territory.
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Affiliation(s)
- Elizabeth Adkins-Regan
- Department of Psychology and Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853-7601, USA.
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43
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Phan A, Lancaster KE, Armstrong JN, MacLusky NJ, Choleris E. Rapid effects of estrogen receptor α and β selective agonists on learning and dendritic spines in female mice. Endocrinology 2011; 152:1492-502. [PMID: 21285321 DOI: 10.1210/en.2010-1273] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Estrogen receptor (ER) agonists rapidly affect neural plasticity within 1 h, suggesting they play a functional role in learning and memory. However, behavioral learning experiments on such a rapid time scale are lacking. Therefore we investigated whether the ERα agonist propyl pyrazole triol (PPT) and ERβ agonist diarylpropionitrile (DPN) could affect social recognition, object recognition, or object placement learning within 40 min of drug administration. At the same time, we examined their effects on CA1 hippocampal dendritic spines. Ovariectomized female CD1 mice were administered a range of PPT or DPN doses (0, 30, 50, 75, or 150 μg/mouse). PPT at the middle doses improved social recognition, facilitated object recognition and placement at a dose of 75 μg, and increased dendritic spine density in the stratum radiatum and lacunosum-moleculare. In contrast, DPN impaired social recognition at higher doses, did not affect object recognition, but slightly facilitated object placement learning at the 75-μg dose. DPN did not affect spines in the stratum radiatum but decreased spine density and increased spine length in the lacunosum-moleculare. This suggests that rapid estrogen-mediated learning enhancements may predominantly be mediated through ERα, while the effects of DPN are weaker and may depend on the learning paradigm. The role of ERα and ERβ in learning and memory may vary depending on the timing of drug administration, as genomic studies often implicate ERβ in enhancing effects on learning and memory. To our knowledge, this is the first report of estrogens' effects on learning within such a short time frame.
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Affiliation(s)
- Anna Phan
- Department of Psychology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
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44
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Arakawa H, Arakawa K, Deak T. Oxytocin and vasopressin in the medial amygdala differentially modulate approach and avoidance behavior toward illness-related social odor. Neuroscience 2010; 171:1141-51. [DOI: 10.1016/j.neuroscience.2010.10.013] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Revised: 09/29/2010] [Accepted: 10/03/2010] [Indexed: 11/15/2022]
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45
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Lau BWM, Yau SY, Lee TMC, Ching YP, Tang SW, So KF. Effect of corticosterone and paroxetine on masculine mating behavior: possible involvement of neurogenesis. J Sex Med 2010; 8:1390-403. [PMID: 20955318 DOI: 10.1111/j.1743-6109.2010.02081.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Corticosterone inhibits male rodent sexual behavior while the mechanism remains obscured. Recent studies have disclosed that neurogenesis in the subventricular zone (SVZ) can be increased by pheromone exposure from the opposite sex, and neurogenesis is essential for normal mating behavior of female mice. Together with the neurogenesis-inhibiting effect of corticosterone, we hypothesize that cell proliferation in the olfactory system is essential for male rodent sexual functioning. AIM The current study explored the relationship between cell proliferation in the olfactory system and male sexual behavior. MAIN OUTCOME MEASURES Sexual behavior performance, proliferative cell counts, and c-fos-expressing cell counts. METHODS Adult male rats were treated with corticosterone and/or paroxetine, an antidepressant, for 2 weeks. These two drugs were shown to suppress and enhance hippocampus and SVZ cell proliferation, respectively. Mating behavior was assessed after the treatment, and proliferation of new cells and c-fos-expressing cells, activated neurons in the mating-related regions in the brain, were analyzed. To further confirm the necessity of cell proliferation in mating, inhibition of cell proliferation was performed by intracerebroventricular infusion of cytostatic cytosine arabinose (Ara-c). RESULTS Corticosterone treatment, which inhibited cell proliferation in both the SVZ and olfactory epithelium, led to inhibited male sexual performance. In contrast, paroxetine increased cell proliferation and improved the performance in corticosterone-treated animals. When cell proliferation in the brain was inhibited by Ara-c, a suppressed sexual performance was found. However, cell proliferation in olfactory epithelium was not inhibited by Ara-c and thus the sexual inhibition is unlikely to be linked to this region. Furthermore, a decrease in c-fos expression in the mating-related regions upon female pheromone stimulation was found. CONCLUSIONS These results suggest that cell proliferation in the SVZ and hippocampus may be involved in the reproduction of the male rodents, and pharmacological treatments may affect sexual functioning through alteration of neurogenesis.
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Affiliation(s)
- Benson Wui-Man Lau
- Department of Anatomy, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
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46
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Martinez LA, Albers HE, Petrulis A. Blocking oxytocin receptors inhibits vaginal marking to male odors in female Syrian hamsters. Physiol Behav 2010; 101:685-92. [PMID: 20723552 DOI: 10.1016/j.physbeh.2010.08.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2010] [Revised: 07/29/2010] [Accepted: 08/12/2010] [Indexed: 10/19/2022]
Abstract
In Syrian hamsters (Mesocricetus auratus), precopulatory behaviors such as vaginal scent marking are essential for attracting a suitable mate. Vaginal marking is dependent on forebrain areas implicated in the neural regulation of reproductive behaviors in rodents, including the medial preoptic/anterior hypothalamus (MPOA-AH). Within MPOA-AH, the neuropeptide oxytocin (OT) acts to facilitate copulation (lordosis), as well as ultrasonic vocalizations towards males. It is not known, however, if OT in this area also facilitates vaginal marking. In the present study, a specific oxytocin receptor antagonist (OTA) was injected into MPOA-AH of intact female Syrian hamsters to determine if oxytocin receptor-dependent signaling is critical for the normal expression of vaginal marking elicited by male, female, and clean odors. OTA injections significantly inhibited vaginal marking in response to male odors compared with vehicle injections. There was no effect of OTA on marking in response to either female or clean odors. When injected into the bed nucleus of the stria terminalis (BNST), a nearby region to MPOA-AH, OTA was equally effective in decreasing marking. Finally, the effects of OTA appear to be specific to vaginal marking, as OTA injections in MPOA-AH or BNST did not alter general locomotor activity, flank marking, or social odor investigation. Considered together, these results suggest that OT in MPOA-AH and/or BNST normally facilitates male odor-induced vaginal marking, providing further evidence that OT generally supports prosocial interactions among conspecifics.
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Affiliation(s)
- Luis A Martinez
- Neuroscience Institute, Center for Behavioral Neuroscience, Georgia State University, PO Box 5030, Atlanta, GA 30302-5030, USA.
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Bell MR, Meerts SH, Sisk CL. Male Syrian hamsters demonstrate a conditioned place preference for sexual behavior and female chemosensory stimuli. Horm Behav 2010; 58:410-4. [PMID: 20515693 PMCID: PMC2919302 DOI: 10.1016/j.yhbeh.2010.05.017] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Revised: 05/24/2010] [Accepted: 05/26/2010] [Indexed: 10/19/2022]
Abstract
Sexual behavior is a natural reward for many rodent species, and it often includes chemosensory-directed components. Chemosensory stimuli themselves may also be rewarding. Conditioned place preference (CPP) is one paradigm frequently used to test the rewarding properties of a range of stimuli. Males and females of several rodent species show a CPP for sexual behavior; however, it is currently unknown whether sexual behavior can induce a CPP in male Syrian hamsters. As male Syrian hamsters are an animal model commonly used for investigation of the neurobiology of sexual behavior, understanding the rewarding components of sexual stimuli will better direct future research on brain regions and neurotransmitters involved in these behaviors. Experiment 1 tested the prediction that male hamsters show a CPP for sexual behavior. Female chemosensory stimuli are essential for the display of sexual behavior in male hamsters; however, the rewarding properties of female chemosensory stimuli contained in vaginal secretions (VS) are uncertain. Therefore, experiment 2 tested the prediction that male hamsters show a CPP for VS. This study is the first demonstration that both sexual behavior and VS induce a CPP in male hamsters. Thus, female chemosensory stimuli are a natural reward in a species that is dependent on these stimuli for reproductive fitness.
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Affiliation(s)
- Margaret R Bell
- Neuroscience Program, Michigan State University, East Lansing, MI 48824, USA.
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Sinai L, Duffy S, Roder JC. Src inhibition reduces NR2B surface expression and synaptic plasticity in the amygdala. Learn Mem 2010; 17:364-71. [DOI: 10.1101/lm.1765710] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Carrillo M, Ricci LA, Schwartzer JJ, Melloni RH. Immunohistochemical characterization of 5-HT3A receptors in the Syrian hamster forebrain. Brain Res 2010; 1329:67-81. [DOI: 10.1016/j.brainres.2010.02.038] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Revised: 02/04/2010] [Accepted: 02/09/2010] [Indexed: 12/24/2022]
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Social novelty increases tyrosine hydroxylase immunoreactivity in the extended olfactory amygdala of female prairie voles. Physiol Behav 2010; 100:381-6. [PMID: 20381508 DOI: 10.1016/j.physbeh.2010.03.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Revised: 03/26/2010] [Accepted: 03/30/2010] [Indexed: 10/19/2022]
Abstract
The monogamous social behaviors of prairie voles (Microtus ochrogaster) require olfactory inputs, which are processed by the posterodorsal medial amygdala (MeApd) and principal bed nucleus of the stria terminalis (pBST). The male prairie vole MeApd and pBST contain hundreds of cells densely immunoreactive for tyrosine hydroxylase (TH-ir). Female prairie voles have relatively few of these cells, but we previously found that the number of these TH-ir cells is greatly increased in females by exogenous estradiol. We here hypothesized that the number of TH-ir cells in their MeApd and pBST would also increase during the natural hormone surges associated with females' induced estrus. We found that the number of TH-ir cells in both sites did significantly increase after females cohabitated for two days with an unfamiliar male. However, this increase did not require the presence of ovaries and even tended to occur in the pBST of females cohabitating for two days with unfamiliar females. We then determined if the greater number of TH-ir cells after heterosexual pairing was transient by examining two groups of long-term pairbonded females (primiparous and multiparous), and found these females also had significantly more TH-ir cells in the pBST and/or MeApd compared to unmated controls. Thus, social novelty arising from cohabitation with unfamiliar conspecifics produces a reoccurring increase in the number of TH-ir cells in the female prairie vole extended olfactory amygdala. Ovarian hormones are not necessarily required. This increase in catecholaminergic cells may facilitate acquisition and retention of olfactory memories necessary for social recognition in this species.
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