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Kawakami C, Naoi T, Sakaguchi M. Spaced conditioned stimulus presentation facilitates the extinction of strong fear memory in mice. Biochem Biophys Res Commun 2024; 718:150071. [PMID: 38735136 DOI: 10.1016/j.bbrc.2024.150071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Accepted: 05/07/2024] [Indexed: 05/14/2024]
Abstract
Inducing fear memory extinction by re-presenting a conditioned stimulus (CS) is the foundation of exposure therapy for post-traumatic stress disorder (PTSD). Investigating differences in the ability of different CS presentation patterns to induce extinction learning is crucial for improving this type of therapy. Using a trace fear conditioning paradigm in mice, we demonstrate that spaced presentation of the CS facilitated the extinction of a strong fear memory to a greater extent than continuous CS presentation. These results lay the groundwork for developing more effective exposure therapy techniques for PTSD.
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Affiliation(s)
- Chinatsu Kawakami
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki, 305-0006, Japan; Ph.D. Program in Humanics, Graduate School, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Toshie Naoi
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki, 305-0006, Japan
| | - Masanori Sakaguchi
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki, 305-0006, Japan; Ph.D. Program in Humanics, Graduate School, University of Tsukuba, Tsukuba, Ibaraki, Japan.
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2
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Cheng HY, Fournier DI, Todd TP. Retrosplenial cortex and aversive conditioning. Front Behav Neurosci 2024; 18:1341705. [PMID: 38983870 PMCID: PMC11232490 DOI: 10.3389/fnbeh.2024.1341705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 02/26/2024] [Indexed: 07/11/2024] Open
Abstract
The retrosplenial cortex (RSC) is well-known for its contribution to episodic memory, as well as contextual and spatial learning and memory. However, two literatures have also emerged examining the role of the RSC in aversive conditioning. The purpose of this manuscript is to review, and attempt to integrate, these two literatures. We focus on studies in which discrete cues, such as tones, predict the occurrence of aversive outcomes, such as mild shocks. Using both electrophysiological recordings and lesion methods, the first literature has examined RSC contributions to discriminative avoidance conditioning. The second, and more recent literature, has focused on the role of the RSC in Pavlovian fear conditioning. We discuss both literatures in terms of the type of information processed by the RSC, the role of the RSC in memory storage, and how the aversive conditioning literature might be consistent with a role for the RSC in contextual learning and memory.
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Affiliation(s)
| | | | - Travis P. Todd
- Department of Psychological Science, University of Vermont, Burlington, VT, United States
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3
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Patrick MB, Preveza NJ, Kincaid SE, Setenet G, Abraham JR, Cummings A, Banani S, Ray WK, Helm RF, Trask S, Jarome TJ. Dysregulation of baseline and learning-dependent protein degradation in the aged hippocampus. Brain Res Bull 2024; 215:111015. [PMID: 38879089 DOI: 10.1016/j.brainresbull.2024.111015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Revised: 06/08/2024] [Accepted: 06/12/2024] [Indexed: 06/21/2024]
Abstract
The ubiquitin-proteasome system (UPS) controls the majority of protein degradation in cells and dysregulation of the UPS has been implicated in the pathophysiology of numerous neurodegenerative disorders, including Alzheimer's disease. Further, strong evidence supports a critical role for the UPS in synaptic plasticity and memory formation. However, while proteasome function is known to decrease broadly in the brain across the lifespan, whether it changes in the hippocampus, a region critical for memory storage and among the first impacted in Alzheimer's disease, at rest and following learning in the aged brain remains unknown. Further, which proteins have altered targeting for protein degradation in the aged hippocampus has yet to be explored and whether learning in advanced age interacts with changes in ubiquitin-proteasome function across the lifespan remains unknown. Here, using proteasome activity assays and unbiased proteomic analyses, we report age-dependent changes in proteasome activity and degradation-specific K48 polyubiquitin protein targeting in the hippocampus and retrosplenial cortex of male and female rats across the lifespan. In the hippocampus, the targets of altered protein degradation were involved in transcription and astrocyte structure or G-protein and Interferon signaling in males and females, respectively. Importantly, we found that contextual fear conditioning led to an increase in proteasome activity and K48 polyubiquitin protein targeting in the hippocampus of aged male rats, a result in direct contrast to what was previously reported in young adult animals. Together, these data suggest that changes in protein degradation in the hippocampus across the lifespan may be contributing to age-related memory loss.
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Affiliation(s)
- Morgan B Patrick
- School of Neuroscience, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Natalie J Preveza
- School of Animal Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Shannon E Kincaid
- School of Animal Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Gueladouan Setenet
- School of Animal Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Jennifer R Abraham
- School of Neuroscience, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Adam Cummings
- School of Neuroscience, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Shifa Banani
- School of Neuroscience, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - W Keith Ray
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Richard F Helm
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Sydney Trask
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, USA
| | - Timothy J Jarome
- School of Neuroscience, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA; School of Animal Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
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4
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Sheppard PAS, Oomen CA, Bussey TJ, Saksida LM. The Granular Retrosplenial Cortex Is Necessary in Male Rats for Object-Location Associative Learning and Memory, But Not Spatial Working Memory or Visual Discrimination and Reversal, in the Touchscreen Operant Chamber. eNeuro 2024; 11:ENEURO.0120-24.2024. [PMID: 38844347 PMCID: PMC11208985 DOI: 10.1523/eneuro.0120-24.2024] [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: 03/18/2024] [Revised: 05/28/2024] [Accepted: 05/30/2024] [Indexed: 06/20/2024] Open
Abstract
The retrosplenial cortex (RSC) is a hub of diverse afferent and efferent projections thought to be involved in associative learning. RSC shows early pathology in mild cognitive impairment and Alzheimer's disease (AD), which impairs associative learning. To understand and develop therapies for diseases such as AD, animal models are essential. Given the importance of human RSC in object-location associative learning and the success of object-location associative paradigms in human studies and in the clinic, it would be of considerable value to establish a translational model of object-location learning for the rodent. For this reason, we sought to test the role of RSC in object-location learning in male rats using the object-location paired-associates learning (PAL) touchscreen task. First, increased cFos immunoreactivity was observed in granular RSC following PAL training when compared with extended pretraining controls. Following this, RSC lesions following PAL acquisition were used to explore the necessity of the RSC in object-location associative learning and memory and two tasks involving only one modality: trial-unique nonmatching-to-location for spatial working memory and pairwise visual discrimination/reversal. RSC lesions impaired both memory for learned paired-associates and learning of new object-location associations but did not affect performance in either the spatial or visual single-modality tasks. These findings provide evidence that RSC is necessary for object-location learning and less so for learning and memory involving the individual modalities therein.
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Affiliation(s)
- Paul A S Sheppard
- Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, ON N6A 5B7, Canada
| | - Charlotte A Oomen
- Department of Experimental Psychology, University of Cambridge, Cambridge CB2 1TN, United Kingdom
- MRC and Wellcome Trust Behavioural and Clinical Neurosciences Institute, University of Cambridge, Cambridge CB2 1TN, United Kingdom
| | - Timothy J Bussey
- Department of Experimental Psychology, University of Cambridge, Cambridge CB2 1TN, United Kingdom
- MRC and Wellcome Trust Behavioural and Clinical Neurosciences Institute, University of Cambridge, Cambridge CB2 1TN, United Kingdom
| | - Lisa M Saksida
- Department of Experimental Psychology, University of Cambridge, Cambridge CB2 1TN, United Kingdom
- MRC and Wellcome Trust Behavioural and Clinical Neurosciences Institute, University of Cambridge, Cambridge CB2 1TN, United Kingdom
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Robinson PK, Met Hoxha E, Williams D, Kinzig KP, Trask S. Fear extinction is impaired in aged rats. GeroScience 2024; 46:2815-2825. [PMID: 38349449 PMCID: PMC11009175 DOI: 10.1007/s11357-024-01084-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 01/17/2024] [Indexed: 04/13/2024] Open
Abstract
Normal aging is accompanied by broad loss of cognitive function in humans and rodents, including declines in cognitive flexibility. In extinction, a conditional stimulus (CS) that was previously paired with a footshock is presented alone. This procedure reliably reduces conditional freezing behavior in young adult rats. Here, we aimed to investigate how normal aging affects extinction learning. Using young (3 months) and aged (20 months) male and female Long Evans rats, we compared extinction (using 20 CS-alone presentations) to a no extinction control (equal exposure to the conditioning chamber without CS presentations) following delay fear conditioning. We found that young animals in the extinction group showed a decrease in freezing following extinction; aged animals did not. We next examined changes in neural activity using expression of the immediate early gene zif268. In young animals, extinction corresponded with decreased expression of zif268 in the basolateral amygdala and anterior retrosplenial cortex; this was not observed in aged animals. Further, aged animals showed increased zif268 expression in each region examined, suggesting that dysfunction in neural activity precedes cognitive deficits. These results demonstrate that aging impacts both extinction learning and neural activity.
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Affiliation(s)
- Payton K Robinson
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, 47907, USA
| | - Erisa Met Hoxha
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, 47907, USA
| | - Destine Williams
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, 47907, USA
| | - Kimberly P Kinzig
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, 47907, USA
- Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA
| | - Sydney Trask
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, 47907, USA.
- Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, 47907, USA.
- Center On Aging and the Life Course, Purdue University, West Lafayette, IN, 47907, USA.
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6
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Diehl MM, Moscarello JM, Trask S. Behavioral outputs and overlapping circuits between conditional fear and active avoidance. Neurobiol Learn Mem 2024; 213:107943. [PMID: 38821256 DOI: 10.1016/j.nlm.2024.107943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 05/19/2024] [Accepted: 05/27/2024] [Indexed: 06/02/2024]
Abstract
Aversive learning can produce a wide variety of defensive behavioral responses depending on the circumstances, ranging from reactive responses like freezing to proactive avoidance responses. While most of this initial learning is behaviorally supported by an expectancy of an aversive outcome and neurally supported by activity within the basolateral amygdala, activity in other brain regions become necessary for the execution of defensive strategies that emerge in other aversive learning paradigms such as active avoidance. Here, we review the neural circuits that support both reactive and proactive defensive behaviors that are motivated by aversive learning, and identify commonalities between the neural substrates of these distinct (and often exclusive) behavioral strategies.
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Affiliation(s)
- Maria M Diehl
- Department of Psychological Sciences, Kansas State University, Manhattan, KS, USA
| | | | - Sydney Trask
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, USA; Purdue Institute for Integrative Neuroscience, West Lafayette, IN, USA.
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Hu YB, Deng X, Liu L, Cao CC, Su YW, Gao ZJ, Cheng X, Kong D, Li Q, Shi YW, Wang XG, Ye X, Zhao H. Distinct roles of excitatory and inhibitory neurons in the medial prefrontal cortex in the expression and reconsolidation of methamphetamine-associated memory in male mice. Neuropsychopharmacology 2024:10.1038/s41386-024-01879-2. [PMID: 38730034 DOI: 10.1038/s41386-024-01879-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 04/26/2024] [Accepted: 04/29/2024] [Indexed: 05/12/2024]
Abstract
Methamphetamine, a commonly abused drug, is known for its high relapse rate. The persistence of addictive memories associated with methamphetamine poses a significant challenge in preventing relapse. Memory retrieval and subsequent reconsolidation provide an opportunity to disrupt addictive memories. However, the key node in the brain network involved in methamphetamine-associated memory retrieval has not been clearly defined. In this study, using the conditioned place preference in male mice, whole brain c-FOS mapping and functional connectivity analysis, together with chemogenetic manipulations of neural circuits, we identified the medial prefrontal cortex (mPFC) as a critical hub that integrates inputs from the retrosplenial cortex and the ventral tegmental area to support both the expression and reconsolidation of methamphetamine-associated memory during its retrieval. Surprisingly, with further cell-type specific analysis and manipulation, we also observed that methamphetamine-associated memory retrieval activated inhibitory neurons in the mPFC to facilitate memory reconsolidation, while suppressing excitatory neurons to aid memory expression. These findings provide novel insights into the neural circuits and cellular mechanisms involved in the retrieval process of addictive memories. They suggest that targeting the balance between excitation and inhibition in the mPFC during memory retrieval could be a promising treatment strategy to prevent relapse in methamphetamine addiction.
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Affiliation(s)
- Yu-Bo Hu
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
- Guangdong Province Translational Forensic Medicine Engineering Technology Research Center, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
- Guangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
| | - Xi Deng
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
| | - Lu Liu
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
| | - Can-Can Cao
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
| | - Ya-Wen Su
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
| | - Zhen-Jie Gao
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
| | - Xin Cheng
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
| | - Deshan Kong
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
| | - Qi Li
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
| | - Yan-Wei Shi
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
- Guangdong Province Translational Forensic Medicine Engineering Technology Research Center, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
- Guangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
| | - Xiao-Guang Wang
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
- Guangdong Province Translational Forensic Medicine Engineering Technology Research Center, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
- Guangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China
| | - Xiaojing Ye
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China.
- Guangdong Province Translational Forensic Medicine Engineering Technology Research Center, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China.
- Guangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China.
| | - Hu Zhao
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China.
- Guangdong Province Translational Forensic Medicine Engineering Technology Research Center, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China.
- Guangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China.
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McElroy DL, Sabir H, Glass AE, Greba Q, Howland JG. The anterior retrosplenial cortex is required for short-term object in place recognition memory retrieval: Role of ionotropic glutamate receptors in male and female Long-Evans rats. Eur J Neurosci 2024; 59:2260-2275. [PMID: 38411499 DOI: 10.1111/ejn.16284] [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: 09/25/2023] [Revised: 01/24/2024] [Accepted: 02/01/2024] [Indexed: 02/28/2024]
Abstract
The anterior retrosplenial cortex (aRSC) integrates multimodal sensory information into cohesive associative recognition memories. Little is known about how information is integrated during different learning phases (i.e., encoding and retrieval). Additionally, sex differences are observed in performance of some visuospatial memory tasks; however, inconsistent findings warrant more research. We conducted three experiments using the 1-h delay object-in-place (1-h OiP) test to assess recognition memory retrieval in male and female Long-Evans rats. (i) We found both sexes performed equally in three repeated 1-h OiP test sessions. (ii) We showed infusions of a mixture of muscimol/baclofen (GABAA/B receptor agonists) into the aRSC ~15-min prior to the test phase disrupted 1-h OiP in both sexes. (iii) We assessed the role of aRSC ionotropic glutamate receptors in 1-h OiP retrieval using another squad of cannulated rats and confirmed that infusions of either the competitive AMPA/Kainate receptor antagonist CNQX (3 mM) or competitive NMDA receptor antagonist AP-5 (30 mM) (volumes = 0.50 uL/side) significantly impaired 1-h OiP retrieval in both sexes compared to controls. Taken together, findings challenge reported sex differences and clearly establish a role for aRSC ionotropic glutamate receptors in short-term visuospatial recognition memory retrieval. Thus, modulating neural activity in the aRSC may alleviate some memory processing impairments in related disorders.
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Affiliation(s)
- Dan L McElroy
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Hassaan Sabir
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Aiden E Glass
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Quentin Greba
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - John G Howland
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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Leibovitz SE, Sevinc G, Greenberg J, Hölzel B, Gard T, Calahan T, Vangel M, Orr SP, Milad MR, Lazar SW. Mindfulness training and exercise differentially impact fear extinction neurocircuitry. Psychol Med 2024; 54:835-846. [PMID: 37655520 DOI: 10.1017/s0033291723002593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
BACKGROUND The ability to extinguish a maladaptive conditioned fear response is crucial for healthy emotional processing and resiliency to aversive experiences. Therefore, enhancing fear extinction learning has immense potential emotional and health benefits. Mindfulness training enhances both fear conditioning and recall of extinguished fear; however, its effects on fear extinction learning are unknown. Here we investigated the impact of mindfulness training on brain mechanisms associated with fear-extinction learning, compared to an exercise-based program. METHODS We investigated BOLD activations in response to a previously learned fear-inducing cue during an extinction paradigm, before and after an 8-week mindfulness-based stress reduction program (MBSR, n = 49) or exercise-based stress management education program (n = 27). RESULTS The groups exhibited similar reductions in stress, but the MBSR group was uniquely associated with enhanced activation of salience network nodes and increased hippocampal engagement. CONCLUSIONS Our results suggest that mindfulness training increases attention to anticipatory aversive stimuli, which in turn facilitates decreased aversive subjective responses and enhanced reappraisal of the memory.
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Affiliation(s)
- Shaked E Leibovitz
- College of Faculty of Arts and Sciences, Harvard University, Cambridge, MA 02138, USA
| | - Gunes Sevinc
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Jonathan Greenberg
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Britta Hölzel
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
- Department of Neuroradiology, Klinikum rechts der Isar, Technical University of Munich, Munich 81675, Germany
| | - Tim Gard
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Thomas Calahan
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Mark Vangel
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Scott P Orr
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Mohammed R Milad
- Psychiatry Department, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Sara W Lazar
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
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10
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Met Hoxha E, Robinson PK, Greer KM, Trask S. Generalization and discrimination of inhibitory avoidance differentially engage anterior and posterior retrosplenial subregions. Front Behav Neurosci 2024; 18:1327858. [PMID: 38304851 PMCID: PMC10832059 DOI: 10.3389/fnbeh.2024.1327858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 01/05/2024] [Indexed: 02/03/2024] Open
Abstract
Introduction In a variety of behavioral procedures animals will show selective fear responding in shock-associated contexts, but not in other contexts. However, several factors can lead to generalized fear behavior, where responding is no longer constrained to the conditioning context and will transfer to novel contexts. Methods Here, we assessed memory generalization using an inhibitory avoidance paradigm to determine if generalized avoidance behavior engages the retrosplenial cortex (RSC). Male and female Long Evans rats received inhibitory avoidance training prior to testing in the same context or a shifted context in two distinct rooms; one room that had fluorescent lighting (Light) and one that had red LED lighting (Dark). Results We found that animals tested in a light context maintained context-specificity; animals tested in the same context as training showed longer latencies to cross and animals tested in the shifted context showed shorter latencies to cross. However, animals tested in the dark generalized their avoidance behavior; animals tested in the same context and animals tested in the shifted context showed similarly-high latencies to cross. We next examined expression of the immediate early gene zif268 and perineuronal nets (PNNs) following testing and found that while activity in the basolateral amygdala corresponded with overall levels of avoidance behaviors, anterior RSC (aRSC) activity corresponded with learned avoidance generally, but posterior RSC (pRSC) activity seemed to correspond with generalized memory. PNN reduction in the RSC was associated with memory formation and retrieval, suggesting a role for PNNs in synaptic plasticity. Further, PNNs did not reduce in the RSC in animals who showed a generalized avoidance behavior, in line with their hypothesized role in memory consolidation. Discussion These findings suggest that there is differential engagement of retrosplenial subregions along the rostrocaudal axis to generalization and discrimination.
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Affiliation(s)
- Erisa Met Hoxha
- Purdue University Department of Psychological Sciences, West Lafayette, IN, United States
| | - Payton K Robinson
- Purdue University Department of Psychological Sciences, West Lafayette, IN, United States
| | - Kaitlyn M Greer
- Purdue University Department of Psychological Sciences, West Lafayette, IN, United States
| | - Sydney Trask
- Purdue University Department of Psychological Sciences, West Lafayette, IN, United States
- Purdue University Institute for Integrative Neuroscience, West Lafayette, IN, United States
- Purdue University Center on Aging and the Life Course, West Lafayette, IN, United States
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11
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Jin B, Gongwer MW, Ohanian L, Holden-Wingate L, Le B, Darmawan A, Nakayama Y, Rueda Mora SA, DeNardo LA. A developmental brain-wide screen identifies retrosplenial cortex as a key player in the emergence of persistent memory. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.07.574554. [PMID: 38260633 PMCID: PMC10802387 DOI: 10.1101/2024.01.07.574554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Memories formed early in life are short-lived while those formed later persist. Recent work revealed that infant memories are stored in a latent state. But why they fail to be retrieved is poorly understood. Here we investigated brain-wide circuit mechanisms underlying infantile amnesia in mice. We performed a screen that combined activity-dependent neuronal tagging at different postnatal ages, tissue clearing and light sheet microscopy. We observed striking developmental transitions in the organization of fear memory networks and changes in the activity and functional connectivity of the retrosplenial cortex (RSP) that aligned with the emergence of persistent memory. 7 days after learning, chemogenetic reactivation of tagged RSP ensembles enhanced memory in adults but not in infants. But after 33 days, reactivating infant-tagged RSP ensembles recovered forgotten memories. These studies show that RSP ensembles store latent infant memories, reveal the time course of RSP functional maturation, and suggest that immature RSP functional networks contribute to infantile amnesia.
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12
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Wang JH, Wu C, Lian YN, Cao XW, Wang ZY, Dong JJ, Wu Q, Liu L, Sun L, Chen W, Chen WJ, Zhang Z, Zhuo M, Li XY. Single-cell RNA sequencing uncovers the cell type-dependent transcriptomic changes in the retrosplenial cortex after peripheral nerve injury. Cell Rep 2023; 42:113551. [PMID: 38048224 DOI: 10.1016/j.celrep.2023.113551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 05/14/2023] [Accepted: 11/20/2023] [Indexed: 12/06/2023] Open
Abstract
The retrosplenial cortex (RSC) is a vital area for storing remote memory and has recently been found to undergo broad changes after peripheral nerve injury. However, little is known about the role of RSC in pain regulation. Here, we examine the involvement of RSC in the pain of mice with nerve injury. Notably, reducing the activities of calcium-/calmodulin-dependent protein kinase type II-positive splenial neurons chemogenetically increases paw withdrawal threshold and extends thermal withdrawal latency in mice with nerve injury. The single-cell or single-nucleus RNA-sequencing results predict enhanced excitatory synaptic transmissions in RSC induced by nerve injury. Local infusion of 1-naphthyl acetyl spermine into RSC to decrease the excitatory synaptic transmissions relieves pain and induces conditioned place preference. Our data indicate that RSC is critical for regulating physiological and neuropathic pain. The cell type-dependent transcriptomic information would help understand the molecular basis of neuropathic pain.
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Affiliation(s)
- Jing-Hua Wang
- Department of Psychiatry of the Fourth Affiliated Hospital, International Institutes of Medicine, Zhejiang University School of Medicine, Yiwu, Zhejiang 322000, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain, Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Cheng Wu
- Department of Psychiatry of the Fourth Affiliated Hospital, International Institutes of Medicine, Zhejiang University School of Medicine, Yiwu, Zhejiang 322000, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain, Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China; Zhejiang University-University of Edinburgh Institute, Zhejiang University School of Medicine, Zhejiang University, Haining, Zhejiang 314400, China; Biomedical Sciences, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh EH8 9JU, UK
| | - Yan-Na Lian
- Department of Psychiatry of the Fourth Affiliated Hospital, International Institutes of Medicine, Zhejiang University School of Medicine, Yiwu, Zhejiang 322000, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain, Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Xiao-Wen Cao
- Department of Psychiatry of the Fourth Affiliated Hospital, International Institutes of Medicine, Zhejiang University School of Medicine, Yiwu, Zhejiang 322000, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain, Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Zi-Yue Wang
- NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain, Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jia-Jun Dong
- Zhejiang University-University of Edinburgh Institute, Zhejiang University School of Medicine, Zhejiang University, Haining, Zhejiang 314400, China
| | - Qin Wu
- Zhejiang University-University of Edinburgh Institute, Zhejiang University School of Medicine, Zhejiang University, Haining, Zhejiang 314400, China
| | - Li Liu
- Core Facilities of the School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Li Sun
- NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain, Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Wei Chen
- Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
| | - Wen-Juan Chen
- Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, China
| | - Zhi Zhang
- Key Laboratory of Brain Functions and Diseases, School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Min Zhuo
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Xiang-Yao Li
- Department of Psychiatry of the Fourth Affiliated Hospital, International Institutes of Medicine, Zhejiang University School of Medicine, Yiwu, Zhejiang 322000, China; NHC and CAMS Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain, Research and Brain-Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, Zhejiang 310058, China; Zhejiang University-University of Edinburgh Institute, Zhejiang University School of Medicine, Zhejiang University, Haining, Zhejiang 314400, China; Biomedical Sciences, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh EH8 9JU, UK.
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13
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Santos TB, Kramer-Soares JC, de Oliveira Coelho CA, Oliveira MGM. Functional network of contextual and temporal memory has increased amygdala centrality and connectivity with the retrosplenial cortex, thalamus, and hippocampus. Sci Rep 2023; 13:13087. [PMID: 37567967 PMCID: PMC10421896 DOI: 10.1038/s41598-023-39946-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 08/02/2023] [Indexed: 08/13/2023] Open
Abstract
In fear conditioning with time intervals between the conditioned (CS) and unconditioned (US) stimuli, a neural representation of the CS must be maintained over time to be associated with the later US. Usually, temporal associations are studied by investigating individual brain regions. It remains unknown, however, the effect of the interval at the network level, uncovering functional connections cooperating for the CS transient memory and its fear association. We investigated the functional network supporting temporal associations using a task in which a 5-s interval separates the contextual CS from the US (CFC-5s). We quantified c-Fos expression in forty-nine brain regions of male rats following the CFC-5s training, used c-Fos correlations to generate functional networks, and analyzed them by graph theory. Control groups were trained in contextual fear conditioning, in which CS and US overlap. The CFC-5s training additionally activated subdivisions of the basolateral, lateral, and medial amygdala; prelimbic, infralimbic, perirhinal, postrhinal, and intermediate entorhinal cortices; ventral CA1 and subiculum. The CFC-5s network had increased amygdala centrality and higher amygdala internal and external connectivity with the retrosplenial cortex, thalamus, and hippocampus. Amygdala and thalamic nuclei were network hubs. Functional connectivity among these brain regions could support CS transient memories and their association.
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Affiliation(s)
- Thays Brenner Santos
- Departamento de Psicobiologia, Universidade Federal de São Paulo - UNIFESP, São Paulo, 04023-062, Brazil
| | - Juliana Carlota Kramer-Soares
- Departamento de Psicobiologia, Universidade Federal de São Paulo - UNIFESP, São Paulo, 04023-062, Brazil
- Universidade Cruzeiro do Sul - UNICSUL, São Paulo, 08060-070, Brazil
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14
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Laing BT, Anderson MS, Bonaventura J, Jayan A, Sarsfield S, Gajendiran A, Michaelides M, Aponte Y. Anterior hypothalamic parvalbumin neurons are glutamatergic and promote escape behavior. Curr Biol 2023; 33:3215-3228.e7. [PMID: 37490921 PMCID: PMC10529150 DOI: 10.1016/j.cub.2023.06.070] [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: 09/21/2022] [Revised: 05/19/2023] [Accepted: 06/28/2023] [Indexed: 07/27/2023]
Abstract
The anterior hypothalamic area (AHA) is a critical structure for defensive responding. Here, we identified a cluster of parvalbumin-expressing neurons in the AHA (AHAPV) that are glutamatergic with fast-spiking properties and send axonal projections to the dorsal premammillary nucleus (PMD). Using in vivo functional imaging, optogenetics, and behavioral assays, we determined the role of these AHAPV neurons in regulating behaviors essential for survival. We observed that AHAPV neuronal activity significantly increases when mice are exposed to a predator, and in a real-time place preference assay, we found that AHAPV neuron photoactivation is aversive. Moreover, activation of both AHAPV neurons and the AHAPV → PMD pathway triggers escape responding during a predator-looming test. Furthermore, escape responding is impaired after AHAPV neuron ablation, and anxiety-like behavior as measured by the open field and elevated plus maze assays does not seem to be affected by AHAPV neuron ablation. Finally, whole-brain metabolic mapping using positron emission tomography combined with AHAPV neuron photoactivation revealed discrete activation of downstream areas involved in arousal, affective, and defensive behaviors including the amygdala and the substantia nigra. Our results indicate that AHAPV neurons are a functional glutamatergic circuit element mediating defensive behaviors, thus expanding the identity of genetically defined neurons orchestrating fight-or-flight responses. Together, our work will serve as a foundation for understanding neuropsychiatric disorders triggered by escape such as post-traumatic stress disorder (PTSD).
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Affiliation(s)
- Brenton T Laing
- Neuronal Circuits and Behavior Section, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD 21224-6823, USA
| | - Megan S Anderson
- Neuronal Circuits and Behavior Section, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD 21224-6823, USA
| | - Jordi Bonaventura
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD 21224-6823, USA
| | - Aishwarya Jayan
- Neuronal Circuits and Behavior Section, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD 21224-6823, USA
| | - Sarah Sarsfield
- Neuronal Circuits and Behavior Section, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD 21224-6823, USA
| | - Anjali Gajendiran
- Neuronal Circuits and Behavior Section, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD 21224-6823, USA
| | - Michael Michaelides
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD 21224-6823, USA; Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Yeka Aponte
- Neuronal Circuits and Behavior Section, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD 21224-6823, USA; The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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15
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Brunswick CA, Baldwin DJ, Bodinayake KK, McKenna AR, Lo CY, Bellfy L, Urban MW, Stuart EM, Murakami S, Smies CW, Kwapis JL. The clock gene Per1 is necessary in the retrosplenial cortex-but not in the suprachiasmatic nucleus-for incidental learning in young and aging male mice. Neurobiol Aging 2023; 126:77-90. [PMID: 36958103 PMCID: PMC10106450 DOI: 10.1016/j.neurobiolaging.2023.02.009] [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: 10/17/2022] [Revised: 02/03/2023] [Accepted: 02/18/2023] [Indexed: 02/24/2023]
Abstract
Aging impairs both circadian rhythms and memory, though the relationship between these impairments is not fully understood. Circadian rhythms are largely dictated by clock genes within the body's central pacemaker, the suprachiasmatic nucleus (SCN), though these genes are also expressed in local clocks throughout the body. As circadian rhythms can directly affect memory performance, one possibility is that memory deficits observed with age are downstream of global circadian rhythm disruptions stemming from the SCN. Here, we demonstrate that expression of clock gene Period1 within a memory-relevant cortical structure, the retrosplenial cortex (RSC), is necessary for incidental learning, and that age-related disruption of Period1 within the RSC-but not necessarily the SCN-contributes to cognitive decline. These data expand the known functions of clock genes beyond maintaining circadian rhythms and suggests that age-associated changes in clock gene expression modulates circadian rhythms and memory performance in a brain region-dependent manner.
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Affiliation(s)
- Chad A Brunswick
- Department of Biology, Pennsylvania State University, University Park, PA
| | - Derek J Baldwin
- Department of Biology, Pennsylvania State University, University Park, PA
| | - Kasuni K Bodinayake
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA
| | | | - Chen-Yu Lo
- Department of Biology, Pennsylvania State University, University Park, PA
| | - Lauren Bellfy
- Department of Biology, Pennsylvania State University, University Park, PA
| | - Mark W Urban
- Department of Biology, Pennsylvania State University, University Park, PA
| | - Emily M Stuart
- Department of Biology, Pennsylvania State University, University Park, PA
| | - Shoko Murakami
- Department of Biology, Pennsylvania State University, University Park, PA
| | - Chad W Smies
- Department of Biology, Pennsylvania State University, University Park, PA
| | - Janine L Kwapis
- Department of Biology, Pennsylvania State University, University Park, PA.
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16
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Alexander AS, Place R, Starrett MJ, Chrastil ER, Nitz DA. Rethinking retrosplenial cortex: Perspectives and predictions. Neuron 2023; 111:150-175. [PMID: 36460006 DOI: 10.1016/j.neuron.2022.11.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 08/09/2022] [Accepted: 11/06/2022] [Indexed: 12/03/2022]
Abstract
The last decade has produced exciting new ideas about retrosplenial cortex (RSC) and its role in integrating diverse inputs. Here, we review the diversity in forms of spatial and directional tuning of RSC activity, temporal organization of RSC activity, and features of RSC interconnectivity with other brain structures. We find that RSC anatomy and dynamics are more consistent with roles in multiple sensorimotor and cognitive processes than with any isolated function. However, two more generalized categories of function may best characterize roles for RSC in complex cognitive processes: (1) shifting and relating perspectives for spatial cognition and (2) prediction and error correction for current sensory states with internal representations of the environment. Both functions likely take advantage of RSC's capacity to encode conjunctions among sensory, motor, and spatial mapping information streams. Together, these functions provide the scaffold for intelligent actions, such as navigation, perspective taking, interaction with others, and error detection.
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Affiliation(s)
- Andrew S Alexander
- Department of Psychological and Brain Sciences, Boston University, Boston, MA 02215, USA
| | - Ryan Place
- Department of Cognitive Science, University of California, San Diego, La Jolla, CA 92093, USA
| | - Michael J Starrett
- Department of Neurobiology & Behavior, University of California, Irvine, Irvine, CA 92697, USA
| | - Elizabeth R Chrastil
- Department of Neurobiology & Behavior, University of California, Irvine, Irvine, CA 92697, USA; Department of Cognitive Sciences, University of California, Irvine, Irvine, CA 92697, USA.
| | - Douglas A Nitz
- Department of Cognitive Science, University of California, San Diego, La Jolla, CA 92093, USA.
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17
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Progression in Time of Dentate Gyrus Granule Cell Layer Widening due to Excitotoxicity Occurs along In Vivo LTP Reinstatement and Contextual Fear Memory Recovery. Neural Plast 2022; 2022:7432842. [PMID: 36213614 PMCID: PMC9533134 DOI: 10.1155/2022/7432842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 07/25/2022] [Accepted: 08/04/2022] [Indexed: 11/17/2022] Open
Abstract
The dentate gyrus (DG) is the gateway of sensory information arriving from the perforant pathway (PP) to the hippocampus. The adequate integration of incoming information into the DG is paramount in the execution of hippocampal-dependent cognitive functions. An abnormal DG granule cell layer (GCL) widening due to granule cell dispersion has been reported under hyperexcitation conditions in animal models as well as in patients with mesial temporal lobe epilepsy, but also in patients with no apparent relation to epilepsy. Strikingly, it is unclear whether the presence and severity of GCL widening along time affect synaptic processing arising from the PP and alter the performance in hippocampal-mediated behaviors. To evaluate the above, we injected excitotoxic kainic acid (KA) unilaterally into the DG of mice and analyzed the evolution of GCL widening at 10 and 30 days post injection (dpi), while analyzing if KA-induced GCL widening affected in vivo long-term potentiation (LTP) in the PP-DG pathway, as well as the performance in learning and memory through contextual fear conditioning. Our results show that at 10 dpi, when a subtle GCL widening was observed, LTP induction, as well as contextual fear memory, were impaired. However, at 30 dpi when a pronounced increase in GCL widening was found, LTP induction and contextual fear memory were already reestablished. These results highlight the plastic potential of the DG to recover some of its functions despite a major structural alteration such as abnormal GCL widening.
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18
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Walsh C, Ridler T, Margetts-Smith G, Garcia Garrido M, Witton J, Randall AD, Brown JT. β Bursting in the Retrosplenial Cortex Is a Neurophysiological Correlate of Environmental Novelty Which Is Disrupted in a Mouse Model of Alzheimer's Disease. J Neurosci 2022; 42:7094-7109. [PMID: 35927034 PMCID: PMC9480878 DOI: 10.1523/jneurosci.0890-21.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/15/2022] [Accepted: 07/18/2022] [Indexed: 11/21/2022] Open
Abstract
The retrosplenial cortex (RSC) plays a significant role in spatial learning and memory and is functionally disrupted in the early stages of Alzheimer's disease (AD). In order to investigate neurophysiological correlates of spatial learning and memory in this region we employed in vivo electrophysiology in awake and freely moving male mice, comparing neural activity between wild-type and J20 mice, a transgenic model of AD-associated amyloidopathy. To determine the response of the RSC to environmental novelty local field potentials (LFPs) were recorded while mice explored novel and familiar recording arenas. In familiar environments we detected short, phasic bursts of β (20-30 Hz) oscillations (β bursts), which arose at a low but steady rate. Exposure to a novel environment rapidly initiated a dramatic increase in the rate, size and duration of β bursts. Additionally, θ-α/β cross-frequency coupling was significantly higher during novelty, and spiking of neurons in the RSC was significantly enhanced during β bursts. Finally, excessive β bursting was seen in J20 mice, including increased β bursting during novelty and familiarity, yet a loss of coupling between β bursts and spiking activity. These findings support the concept that β bursting may be responsible for the activation and reactivation of neuronal ensembles underpinning the formation and maintenance of cortical representations, and that disruptions to this activity in J20 mice may underlie cognitive impairments seen in these animals.SIGNIFICANCE STATEMENT The retrosplenial cortex (RSC) is thought to be involved in the formation, recall and consolidation of contextual memory. The discovery of bursts of β oscillations in this region, which are associated with increased neuronal spiking and strongly upregulated while mice explore novel environments, provides a potential mechanism for the activation of neuronal ensembles, which may underlie the formation of cortical representations of context. Excessive β bursting in the RSC of J20 mice, a mouse model of Alzheimer's disease (AD), alongside the disassociation of β bursting from neuronal spiking, may underlie spatial memory impairments previously shown in these mice. These findings introduce a novel neurophysiological correlate of spatial learning and memory, and a potentially new form of AD-related cortical dysfunction.
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Affiliation(s)
- Callum Walsh
- Department of Clinical and Biomedical Sciences, University of Exeter Medical School, Hatherly Laboratories, Exeter EX4 4PS, United Kingdom
| | - Thomas Ridler
- Department of Clinical and Biomedical Sciences, University of Exeter Medical School, Hatherly Laboratories, Exeter EX4 4PS, United Kingdom
| | - Gabriella Margetts-Smith
- Department of Clinical and Biomedical Sciences, University of Exeter Medical School, Hatherly Laboratories, Exeter EX4 4PS, United Kingdom
| | - Maria Garcia Garrido
- Department of Clinical and Biomedical Sciences, University of Exeter Medical School, Hatherly Laboratories, Exeter EX4 4PS, United Kingdom
| | - Jonathan Witton
- Department of Clinical and Biomedical Sciences, University of Exeter Medical School, Hatherly Laboratories, Exeter EX4 4PS, United Kingdom
| | - Andrew D Randall
- Department of Clinical and Biomedical Sciences, University of Exeter Medical School, Hatherly Laboratories, Exeter EX4 4PS, United Kingdom
| | - Jonathan T Brown
- Department of Clinical and Biomedical Sciences, University of Exeter Medical School, Hatherly Laboratories, Exeter EX4 4PS, United Kingdom
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19
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Terstege DJ, Durante IM, Epp JR. Brain-wide neuronal activation and functional connectivity are modulated by prior exposure to repetitive learning episodes. Front Behav Neurosci 2022; 16:907707. [PMID: 36160680 PMCID: PMC9501867 DOI: 10.3389/fnbeh.2022.907707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 08/23/2022] [Indexed: 11/26/2022] Open
Abstract
Memory storage and retrieval are shaped by past experiences. Prior learning and memory episodes have numerous impacts on brain structure from micro to macroscale. Previous experience with specific forms of learning increases the efficiency of future learning. It is less clear whether such practice effects on one type of memory might also have transferable effects to other forms of memory. Different forms of learning and memory rely on different brain-wide networks but there are many points of overlap in these networks. Enhanced structural or functional connectivity caused by one type of learning may be transferable to another type of learning due to overlap in underlying memory networks. Here, we investigated the impact of prior chronic spatial training on the task-specific functional connectivity related to subsequent contextual fear memory recall in mice. Our results show that mice exposed to prior spatial training exhibited decreased brain-wide activation compared to control mice during the retrieval of a context fear memory. With respect to functional connectivity, we observed changes in several network measures, notably an increase in global efficiency. Interestingly, we also observed an increase in network resilience based on simulated targeted node deletion. Overall, this study suggests that chronic learning has transferable effects on the functional connectivity networks of other types of learning and memory. The generalized enhancements in network efficiency and resilience suggest that learning itself may protect brain networks against deterioration.
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20
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Ghosh M, Yang FC, Rice SP, Hetrick V, Gonzalez AL, Siu D, Brennan EKW, John TT, Ahrens AM, Ahmed OJ. Running speed and REM sleep control two distinct modes of rapid interhemispheric communication. Cell Rep 2022; 40:111028. [PMID: 35793619 PMCID: PMC9291430 DOI: 10.1016/j.celrep.2022.111028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 04/08/2022] [Accepted: 06/10/2022] [Indexed: 11/30/2022] Open
Abstract
Rhythmic gamma-band communication within and across cortical hemispheres is critical for optimal perception, navigation, and memory. Here, using multisite recordings in both rats and mice, we show that even faster ~140 Hz rhythms are robustly anti-phase across cortical hemispheres, visually resembling splines, the interlocking teeth on mechanical gears. Splines are strongest in superficial granular retrosplenial cortex, a region important for spatial navigation and memory. Spline-frequency interhemispheric communication becomes more coherent and more precisely anti-phase at faster running speeds. Anti-phase splines also demarcate high-activity frames during REM sleep. While splines and associated neuronal spiking are anti-phase across retrosplenial hemispheres during navigation and REM sleep, gamma-rhythmic interhemispheric communication is precisely in-phase. Gamma and splines occur at distinct points of a theta cycle and thus highlight the ability of interhemispheric cortical communication to rapidly switch between in-phase (gamma) and anti-phase (spline) modes within individual theta cycles during both navigation and REM sleep. Gamma-rhythmic communication within and across cortical hemispheres is critical for optimal perception, navigation, and memory. Here, Ghosh et al. identify even faster ~140 Hz rhythms, named splines, that reflect anti-phase neuronal synchrony across hemispheres. The balance of anti-phase spline and in-phase gamma communication is dynamically controlled by behavior and sleep.
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Affiliation(s)
- Megha Ghosh
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Fang-Chi Yang
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Sharena P Rice
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA; Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - Vaughn Hetrick
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Alcides Lorenzo Gonzalez
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA; Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - Danny Siu
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Ellen K W Brennan
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA; Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - Tibin T John
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA; Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - Allison M Ahrens
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Omar J Ahmed
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA; Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA; Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI 48109, USA; Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA.
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21
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Marks WD, Yokose J, Kitamura T, Ogawa SK. Neuronal Ensembles Organize Activity to Generate Contextual Memory. Front Behav Neurosci 2022; 16:805132. [PMID: 35368306 PMCID: PMC8965349 DOI: 10.3389/fnbeh.2022.805132] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 02/14/2022] [Indexed: 11/17/2022] Open
Abstract
Contextual learning is a critical component of episodic memory and important for living in any environment. Context can be described as the attributes of a location that are not the location itself. This includes a variety of non-spatial information that can be derived from sensory systems (sounds, smells, lighting, etc.) and internal state. In this review, we first address the behavioral underpinnings of contextual memory and the development of context memory theory, with a particular focus on the contextual fear conditioning paradigm as a means of assessing contextual learning and the underlying processes contributing to it. We then present the various neural centers that play roles in contextual learning. We continue with a discussion of the current knowledge of the neural circuitry and physiological processes that underlie contextual representations in the Entorhinal cortex-Hippocampal (EC-HPC) circuit, as the most well studied contributor to contextual memory, focusing on the role of ensemble activity as a representation of context with a description of remapping, and pattern separation and completion in the processing of contextual information. We then discuss other critical regions involved in contextual memory formation and retrieval. We finally consider the engram assembly as an indicator of stored contextual memories and discuss its potential contribution to contextual memory.
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Affiliation(s)
- William D. Marks
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Jun Yokose
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Takashi Kitamura
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, United States
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Sachie K. Ogawa
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, United States
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22
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Herbst MR, Twining RC, Gilmartin MR. Ventral hippocampal shock encoding modulates the expression of trace cued fear. Neurobiol Learn Mem 2022; 190:107610. [PMID: 35302040 DOI: 10.1016/j.nlm.2022.107610] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 02/02/2022] [Accepted: 03/03/2022] [Indexed: 12/24/2022]
Abstract
The hippocampus is crucial for associative fear learning when the anticipation of threat requires temporal or contextual binding of predictive stimuli as in trace and contextual fear conditioning. Compared with the dorsal hippocampus, far less is known about the contribution of the ventral hippocampus to fear learning. The ventral hippocampus, which is highly interconnected with defensive and emotional networks, has a prominent role in both innate and learned affective behaviors including anxiety, fear, and reward. Lesions or temporary inactivation of the ventral hippocampus impair both cued and contextual fear learning, but whether the ventral hippocampal role in learning is driven by affective processing, associative encoding, or both is not clear. Here, we used trace fear conditioning in mixed sex cohorts to assess the contribution of shock-encoding to the acquisition of cued and contextual fear memories. Trace conditioning requires subjects to associate an auditory conditional stimulus (CS) with a shock unconditional stimulus (UCS) that are separated in time by a 20-s trace interval. We first recorded neuronal activity in the ventral hippocampus during trace fear conditioning and found that ventral CA1 predominantly encoded the shock reinforcer. Potentiated firing to the CS was evident at testing, but no encoding of the trace interval was observed. We then tested the necessity of shock encoding for conditional fear acquisition by optogenetically silencing ventral hippocampal activity during the UCS on each trial of training. Contrary to our predictions, preventing hippocampal shock-evoked firing did not impair associative fear. Instead, it led to a more prolonged expression of CS freezing across test trials, an effect observed in males, but not females. Contextual fear learning was largely intact, although a subset of animals in each sex were differentially affected by shock-silencing. Taken together, the results show that shock encoding in the ventral hippocampus modulates the expression of learned fear in a sex-specific manner.
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Affiliation(s)
- Matthew R Herbst
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI 53233, USA
| | - Robert C Twining
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI 53233, USA
| | - Marieke R Gilmartin
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI 53233, USA.
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23
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Trask S, Fournier DI. Examining a role for the retrosplenial cortex in age-related memory impairment. Neurobiol Learn Mem 2022; 189:107601. [PMID: 35202816 DOI: 10.1016/j.nlm.2022.107601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 02/06/2022] [Accepted: 02/15/2022] [Indexed: 11/29/2022]
Abstract
Aging is often characterized by changes in the ability to form and accurately recall episodic memories, and this is especially evident in neuropsychiatric conditions including Alzheimer's disease and dementia. Memory impairments and cognitive decline associated with aging mirror the impairments observed following damage to the retrosplenial cortex, suggesting that this region might be important for continued cognitive function throughout the lifespan. Here, we review lines of evidence demonstrating that degeneration of the retrosplenial cortex is critically involved in age-related memory impairment and suggest that preservation of function in this region as part of a larger circuit that supports memory maintenance will decrease the deleterious effects of aging on memory processing.
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Affiliation(s)
- Sydney Trask
- Department of Psychological Sciences, Purdue University, United States.
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24
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Fernandez AM, Gutekunst CA, Grogan DP, Pedersen NP, Gross RE. Loss of efferent projections of the hippocampal formation in the mouse intrahippocampal kainic acid model. Epilepsy Res 2022; 180:106863. [PMID: 35114430 DOI: 10.1016/j.eplepsyres.2022.106863] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 12/15/2021] [Accepted: 01/17/2022] [Indexed: 11/16/2022]
Abstract
Unilateral intrahippocampal injection of kainic acid is used as a model of medial temporal lobe epilepsy and provides a platform to study the mechanisms of epilepsy. Here, we used an AAV-9 EYFP-tagged viral vector as an anterograde tracer, injected into the dorsal and ventral hippocampus after kainic acid injection, to map out the efferent hippocampal projections after the development of spontaneous seizures in this model. The purpose of the study was to identify the extent of changes in hippocampal efferent system in several brain regions that receive significant inputs from the hippocampus. Loss of efferent hippocampal fibers was greatest in the retrosplenial cortex where neuronal loss was also observed. Loss of fibers was also observed in the fornix without any specific effect in the lateral mammillary nuclei. Although expected, these observations provide further evidence of the broader network effects as a result of hippocampal cell loss.
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Affiliation(s)
- Alejandra M Fernandez
- Department of Neurosurgery, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Claire-Anne Gutekunst
- Department of Neurosurgery, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Dayton P Grogan
- Department of Neurosurgery, Augusta University Hospital, Augusta, GA, 30912, USA
| | - Nigel P Pedersen
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, 30332, USA; Department of Neurology, Emory University, Atlanta, GA, 30322, USA
| | - Robert E Gross
- Department of Neurosurgery, Emory University School of Medicine, Atlanta, GA, 30322, USA; Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, 30332, USA; Department of Neurology, Emory University, Atlanta, GA, 30322, USA.
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25
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Trask S, Helmstetter FJ. Unique roles for the anterior and posterior retrosplenial cortices in encoding and retrieval of memory for context. Cereb Cortex 2022; 32:3602-3610. [PMID: 35029643 PMCID: PMC9433420 DOI: 10.1093/cercor/bhab436] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 11/04/2021] [Accepted: 11/05/2021] [Indexed: 01/16/2023] Open
Abstract
The rat retrosplenial cortex (RSC) makes critical contributions to learning and memory but these contributions may not be uniform along its rostro-caudal axis. Previous work suggests that event-related and context-related information are differentially encoded by anterior and posterior RSC subregions. Here, we further test this idea using a procedure in which spatial/environmental cues (context) and discrete event memories are acquired separately. All animals received a 5-min pre-exposure to the training context 24 h before contextual fear conditioning where shock was delivered immediately upon being placed in the chamber. Rats were tested for memory for the context the next day. We found that optogenetic inhibition of cells in only the posterior RSC during the pre-exposure phase, when spatial information is encoded, reduced behavioral responding during the subsequent memory test. However, similar inhibition of either the anterior or posterior RSC during shock delivery, when information about both the context and the shock become integrated, impaired memory. Finally, inhibiting cellular activity in only the posterior RSC during memory retrieval during testing reduced responding. Together, these results suggest that while activity in both subregions is needed during the period in which the event-related information becomes integrated with the context representation, the posterior RSC is important for both memory formation and retrieval or expression of memory for information about the context. These results add to a growing literature demonstrating a role for the RSC in integration of multiple aspects of memory, and provide information on how spatial representations reliant on the retrosplenial cortex interact with associative learning.
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Affiliation(s)
- Sydney Trask
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA
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26
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Smith DM, Yang YY, Subramanian DL, Miller AMP, Bulkin DA, Law LM. The limbic memory circuit and the neural basis of contextual memory. Neurobiol Learn Mem 2022; 187:107557. [PMID: 34808337 PMCID: PMC8755583 DOI: 10.1016/j.nlm.2021.107557] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 11/12/2021] [Accepted: 11/15/2021] [Indexed: 01/03/2023]
Abstract
The hippocampus, retrosplenial cortex and anterior thalamus are key components of a neural circuit known to be involved in a variety of memory functions, including spatial, contextual and episodic memory. In this review, we focus on the role of this circuit in contextual memory processes. The background environment, or context, is a powerful cue for memory retrieval, and neural representations of the context provide a mechanism for efficiently retrieving relevant memories while avoiding interference from memories that belong to other contexts. Data from experimental lesions and neural manipulation techniques indicate that each of these regions is critical for contextual memory. Neurophysiological evidence from the hippocampus and retrosplenial cortex suggest that contextual information is represented within this circuit by population-level neural firing patterns that reliably differentiate each context a subject encounters. These findings indicate that encoding contextual information to support context-dependent memory retrieval is a key function of this circuit.
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Affiliation(s)
- David M Smith
- Department of Psychology, Cornell University, Ithaca, NY, United States.
| | - Yan Yu Yang
- Department of Psychology, Cornell University, Ithaca, NY, United States
| | | | - Adam M P Miller
- Department of Psychology, Cornell University, Ithaca, NY, United States
| | - David A Bulkin
- Department of Psychology, Cornell University, Ithaca, NY, United States
| | - L Matthew Law
- Department of Psychology, Cornell University, Ithaca, NY, United States
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27
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Trask S, Mogil JS, Helmstetter FJ, Stucky CL, Sadler KE. Contextual control of conditioned pain tolerance and endogenous analgesic systems. eLife 2022; 11:75283. [PMID: 35275062 PMCID: PMC8937231 DOI: 10.7554/elife.75283] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 03/10/2022] [Indexed: 11/13/2022] Open
Abstract
The mechanisms underlying the transition from acute to chronic pain are unclear but may involve the persistence or strengthening of pain memories acquired in part through associative learning. Contextual cues, which comprise the environment in which events occur, were recently described as a critical regulator of pain memory; both male rodents and humans exhibit increased pain sensitivity in environments recently associated with a single painful experience. It is unknown, however, how repeated exposure to an acute painful unconditioned stimulus in a distinct context modifies pain sensitivity or the expectation of pain in that environment. To answer this question, we conditioned mice to associate distinct contexts with either repeated administration of a mild visceral pain stimulus (intraperitoneal injection of acetic acid) or vehicle injection over the course of 3 days. On the final day of experiments, animals received either an acid injection or vehicle injection prior to being placed into both contexts. In this way, contextual control of pain sensitivity and pain expectation could be tested respectively. When re-exposed to the noxious stimulus in a familiar environment, both male and female mice exhibited context-dependent conditioned analgesia, a phenomenon mediated by endogenous opioid signaling. However, when expecting the presentation of a painful stimulus in a given context, males exhibited conditioned hypersensitivity whereas females exhibited endogenous opioid-mediated conditioned analgesia. These results are evidence that pain perception and engagement of endogenous opioid systems can be modified through their psychological association with environmental cues. Successful determination of the brain circuits involved in this sexually dimorphic anticipatory response may allow for the manipulation of pain memories, which may contribute to the development of chronic pain states.
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Affiliation(s)
- Sydney Trask
- Department of Psychological Sciences, Purdue UniversityWest LafayetteUnited States
| | - Jeffrey S Mogil
- Department of Psychology and Anesthesia, Alan Edwards Centre for Research on Pain, McGill UniversityMontrealCanada
| | - Fred J Helmstetter
- Department of Psychology, University of Wisconsin-MilwaukeeMilwaukeeUnited States
| | - Cheryl L Stucky
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of WisconsinMilwaukeeUnited States
| | - Katelyn E Sadler
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of WisconsinMilwaukeeUnited States
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28
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Trask S, Ferrara NC, Grisales K, Helmstetter FJ. Optogenetic inhibition of either the anterior or posterior retrosplenial cortex disrupts retrieval of a trace, but not delay, fear memory. Neurobiol Learn Mem 2021; 185:107530. [PMID: 34592468 PMCID: PMC8595712 DOI: 10.1016/j.nlm.2021.107530] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 09/03/2021] [Accepted: 09/24/2021] [Indexed: 02/07/2023]
Abstract
Previous work investigating the role of the retrosplenial cortex (RSC) in memory formation has demonstrated that its contributions are not uniform throughout the rostro-caudal axis. While the anterior region was necessary for encoding CS information in a trace conditioning procedure, the posterior retrosplenial cortex was needed to encode contextual information. Using the same behavioral procedure, we tested if there was a similar dissociation during memory retrieval. First, we found that memory retrieval following trace conditioning results in increased neural activity in both the anterior and posterior retrosplenial cortex, measured using the immediate early gene zif268. Similar increases were not found in either RSC subregion using a delay conditioning task. We then found that optogenetic inhibition of neural activity in either subregion impairs retrieval of a trace, but not delay, memory. Together these results add to a growing literature showing a role for the retrosplenial cortex in memory formation and retention. Further, they suggest that following formation, memory storage becomes distributed to a wider network than is needed for its initial consolidation.
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Affiliation(s)
- Sydney Trask
- The University of Wisconsin-Milwaukee, Department of Psychology, United States
| | - Nicole C Ferrara
- The University of Wisconsin-Milwaukee, Department of Psychology, United States
| | - Kevin Grisales
- The University of Wisconsin-Milwaukee, Department of Psychology, United States
| | - Fred J Helmstetter
- The University of Wisconsin-Milwaukee, Department of Psychology, United States.
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29
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Trask S, Ferrara NC, Jasnow AM, Kwapis JL. Contributions of the rodent cingulate-retrosplenial cortical axis to associative learning and memory: A proposed circuit for persistent memory maintenance. Neurosci Biobehav Rev 2021; 130:178-184. [PMID: 34450181 PMCID: PMC8511298 DOI: 10.1016/j.neubiorev.2021.08.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 08/18/2021] [Accepted: 08/22/2021] [Indexed: 10/20/2022]
Abstract
While the anterior cingulate (ACC) and retrosplenial (RSC) cortices have been extensively studied for their role in spatial navigation, less is known about how they contribute to associative learning and later memory recall. The limited work that has been conducted on this topic suggests that each of these cortical regions makes distinct, but similar contributions to associative learning and memory. Here, we review evidence from the rodent literature demonstrating that while ACC activity seems to be necessary at remote time points associated with imprecise or generalized memories, the role of the RSC seems to be uniform over time. Together, the lines of evidence reviewed here suggest that the ACC and RSC likely function together to support memory formation and maintenance following associative learning.
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Affiliation(s)
- Sydney Trask
- Department of Psychological Sciences, Purdue University, West Lafayette, IN, 47907, United States
| | - Nicole C Ferrara
- Department of Pharmacology, Rosalind Franklin University of Medicine and Science, North Chicago, IL, 60064, United States
| | - Aaron M Jasnow
- Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, SC, 29209, United States
| | - Janine L Kwapis
- Department of Biology, Pennsylvania State University, University Park, PA, 16802, United States.
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30
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Urban MW, Lo C, Bodinayake KK, Brunswick CA, Murakami S, Heimann AC, Kwapis JL. The circadian clock gene Per1 modulates context fear memory formation within the retrosplenial cortex in a sex-specific manner. Neurobiol Learn Mem 2021; 185:107535. [PMID: 34624524 PMCID: PMC8595856 DOI: 10.1016/j.nlm.2021.107535] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/27/2021] [Accepted: 09/30/2021] [Indexed: 01/18/2023]
Abstract
Context memory formation is a complex process that requires transcription in many subregions of the brain including the dorsal hippocampus and retrosplenial cortex. One critical gene necessary for memory formation is the circadian gene Period1 (Per1), which has been shown to function in the dorsal hippocampus to modulate spatial memory in addition to its well-documented role in regulating the diurnal clock within the suprachiasmatic nucleus (SCN). We recently found that alterations in Per1 expression in the dorsal hippocampus can modulate spatial memory formation, with reduced hippocampal Per1 impairing memory and overexpression of Per1 ameliorating age-related impairments in spatial memory. Whether Per1 similarly functions within other memory-relevant brain regions is currently unknown. Here, to test whether Per1 is a general mechanism that modulates memory across the brain, we tested the role of Per1 in the retrosplenial cortex (RSC), a brain region necessary for context memory formation. First, we demonstrate that context fear conditioning drives a transient increase in Per1 mRNA expression within the anterior RSC that peaks 60 m after training. Next, using HSV-CRISPRi-mediated knockdown of Per1, we show that reducing Per1 within the anterior RSC before context fear acquisition impairs memory in both male and female mice. In contrast, overexpressing Per1 with either HSV-CRISPRa or HSV-Per1 before context fear acquisition drives a sex-specific memory impairment; males show impaired context fear memory whereas females are not affected by Per1 overexpression. Finally, as Per1 levels are known to rhythmically oscillate across the day/night cycle, we tested the possibility that Per1 overexpression might have different effects on memory depending on the time of day. In contrast to the impairment in memory we observed during the daytime, Per1 overexpression has no effect on context fear memory during the night in either male or female mice. Together, our results indicate that Per1 modulates memory in the anterior retrosplenial cortex in addition to its documented role in regulating memory within the dorsal hippocampus, although this role may differ between males and females.
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Affiliation(s)
- Mark W Urban
- Department of Biology, Pennsylvania State University, University Park, PA 16802, USA
| | - Chenyu Lo
- Department of Biology, Pennsylvania State University, University Park, PA 16802, USA
| | - Kasuni K Bodinayake
- Department of Biology, Pennsylvania State University, University Park, PA 16802, USA
| | - Chad A Brunswick
- Department of Biology, Pennsylvania State University, University Park, PA 16802, USA
| | - Shoko Murakami
- Department of Biology, Pennsylvania State University, University Park, PA 16802, USA
| | - Ashley C Heimann
- Department of Biology, Pennsylvania State University, University Park, PA 16802, USA
| | - Janine L Kwapis
- Department of Biology, Pennsylvania State University, University Park, PA 16802, USA.
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31
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Retrosplenial cortex inactivation during retrieval, but not encoding, impairs remotely acquired auditory fear conditioning in male rats. Neurobiol Learn Mem 2021; 185:107517. [PMID: 34500052 DOI: 10.1016/j.nlm.2021.107517] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 09/01/2021] [Accepted: 09/02/2021] [Indexed: 11/21/2022]
Abstract
Prior studies with permanent lesion methods have demonstrated a role for the retrosplenial cortex (RSC) in the retrieval of remotely, but not recently, acquired delay fear conditioning. To extend the generalizability of these prior findings, the present experiments used chemogenetics to temporarily inactivate the RSC during either retrieval or encoding of delay auditory fear conditioning. Inactivation of the RSC at the time of test impaired retrieval of a remotely conditioned auditory cue, but not a recently conditioned one. In addition, inactivation of the RSC during encoding had no impact on freezing during later retrieval testing for both a remotely and recently conditioned auditory cue. These findings indicate that the RSC contributes to the retrieval, but not encoding, of remotely acquired auditory fear conditioning, and suggest it has less of a role in both retrieval and encoding of recently acquired auditory fear conditioning.
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32
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Brennan EKW, Jedrasiak-Cape I, Kailasa S, Rice SP, Sudhakar SK, Ahmed OJ. Thalamus and claustrum control parallel layer 1 circuits in retrosplenial cortex. eLife 2021; 10:e62207. [PMID: 34170817 PMCID: PMC8233040 DOI: 10.7554/elife.62207] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 05/17/2021] [Indexed: 11/13/2022] Open
Abstract
The granular retrosplenial cortex (RSG) is critical for both spatial and non-spatial behaviors, but the underlying neural codes remain poorly understood. Here, we use optogenetic circuit mapping in mice to reveal a double dissociation that allows parallel circuits in superficial RSG to process disparate inputs. The anterior thalamus and dorsal subiculum, sources of spatial information, strongly and selectively recruit small low-rheobase (LR) pyramidal cells in RSG. In contrast, neighboring regular-spiking (RS) cells are preferentially controlled by claustral and anterior cingulate inputs, sources of mostly non-spatial information. Precise sublaminar axonal and dendritic arborization within RSG layer 1, in particular, permits this parallel processing. Observed thalamocortical synaptic dynamics enable computational models of LR neurons to compute the speed of head rotation, despite receiving head direction inputs that do not explicitly encode speed. Thus, parallel input streams identify a distinct principal neuronal subtype ideally positioned to support spatial orientation computations in the RSG.
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Affiliation(s)
- Ellen KW Brennan
- Department of Psychology, University of MichiganAnn ArborUnited States
- Neuroscience Graduate Program, University of MichiganAnn ArborUnited States
| | | | - Sameer Kailasa
- Department of Mathematics, University of MichiganAnn ArborUnited States
| | - Sharena P Rice
- Department of Psychology, University of MichiganAnn ArborUnited States
- Neuroscience Graduate Program, University of MichiganAnn ArborUnited States
| | | | - Omar J Ahmed
- Department of Psychology, University of MichiganAnn ArborUnited States
- Neuroscience Graduate Program, University of MichiganAnn ArborUnited States
- Michigan Center for Integrative Research in Critical Care, University of MichiganAnn ArborUnited States
- Kresge Hearing Research Institute, University of MichiganAnn ArborUnited States
- Department of Biomedical Engineering, University of MichiganAnn ArborUnited States
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33
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Trask S, Pullins SE, Ferrara NC, Helmstetter FJ. The anterior retrosplenial cortex encodes event-related information and the posterior retrosplenial cortex encodes context-related information during memory formation. Neuropsychopharmacology 2021; 46:1386-1392. [PMID: 33580135 PMCID: PMC8134488 DOI: 10.1038/s41386-021-00959-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 12/22/2020] [Accepted: 12/29/2020] [Indexed: 12/25/2022]
Abstract
The retrosplenial cortex (RSC) is extensively interconnected with the dorsal hippocampus and has several important roles in learning and memory. Recent work has demonstrated that certain types of context-dependent learning are selectively impaired when the posterior, but not the anterior, region of the RSC is damaged, suggesting that the role of the RSC in memory formation may not be uniform along its rostro-caudal axis. The current experiments tested the idea that the anterior and posterior portions of the rat RSC contribute to different aspects of memory formation. We first confirmed that brief optogenetic inhibition of either the anterior or posterior RSC resulted in decreased local cellular activity as indexed by immediate early gene zif268 expression and that this decrease was restricted to the target region within RSC. We then found that silencing the anterior or posterior RSC during trace fear training trials had different effects on memory: While inhibiting neural activity in the anterior RSC had a selective impact on behavior evoked by the auditory CS, inhibition of the posterior RSC selectively impaired memory for the context in which training was conducted. These results contribute to a growing literature that supports functionally distinct roles in learning and memory for subregions of the RSC.
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Affiliation(s)
- Sydney Trask
- grid.267468.90000 0001 0695 7223Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53201 USA
| | - Shane E. Pullins
- grid.267468.90000 0001 0695 7223Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53201 USA
| | - Nicole C. Ferrara
- grid.267468.90000 0001 0695 7223Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53201 USA
| | - Fred J. Helmstetter
- grid.267468.90000 0001 0695 7223Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53201 USA
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34
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Opalka AN, Huang WQ, Liu J, Liang H, Wang DV. Hippocampal Ripple Coordinates Retrosplenial Inhibitory Neurons during Slow-Wave Sleep. Cell Rep 2021; 30:432-441.e3. [PMID: 31940487 PMCID: PMC7007963 DOI: 10.1016/j.celrep.2019.12.038] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 11/01/2019] [Accepted: 12/12/2019] [Indexed: 12/20/2022] Open
Abstract
The hippocampus and retrosplenial cortex (RSC) play indispensable roles in memory formation, and importantly, a hippocampal oscillation known as ripple is key to consolidation of new memories. However, it remains unclear how the hippocampus and RSC communicate and the role of ripple oscillation in coordinating the activity between these two brain regions. Here, we record from the dorsal hippocampus and RSC simultaneously in freely behaving mice during sleep and reveal that the RSC displays a pre-ripple activation associated with slow and fast oscillations. Immediately after ripples, a subpopulation of RSC putative inhibitory neurons increases firing activity, while most RSC putative excitatory neurons decrease activity. Consistently, optogenetic stimulation of this hippocampus-RSC pathway activates and suppresses RSC putative inhibitory and excitatory neurons, respectively. These results suggest that the dorsal hippocampus mainly inhibits RSC activity via its direct innervation of RSC inhibitory neurons, which overshadows the RSC in supporting learning and memory functions. Converging evidence suggests that hippocampal ripple oscillations and their interaction with the neocortex are critical for memory consolidation. By combining electrophysiology and optogenetic techniques in freely behaving mice, Opalka et al. provide direct evidence that hippocampal ripples communicate with retrosplenial cortex (RSC) interneurons and inhibit RSC population activity during sleep-associated memory consolidation.
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Affiliation(s)
- Ashley N Opalka
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Wen-Qiang Huang
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Jun Liu
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Hualou Liang
- School of Biomedical Engineering, Drexel University, Philadelphia, PA 19104, USA
| | - Dong V Wang
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, PA 19129, USA.
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35
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Miller AMP, Serrichio AC, Smith DM. Dual-Factor Representation of the Environmental Context in the Retrosplenial Cortex. Cereb Cortex 2020; 31:2720-2728. [PMID: 33386396 DOI: 10.1093/cercor/bhaa386] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The retrosplenial cortex (RSC) is thought to be involved in a variety of spatial and contextual memory processes. However, we do not know how contextual information might be encoded in the RSC or whether the RSC representations may be distinct from context representations seen in other brain regions such as the hippocampus. We recorded RSC neuronal responses while rats explored different environments and discovered 2 kinds of context representations: one involving a novel rate code in which neurons reliably fire at a higher rate in the preferred context regardless of spatial location, and a second involving context-dependent spatial firing patterns similar to those seen in the hippocampus. This suggests that the RSC employs a unique dual-factor representational mechanism to support contextual memory.
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Affiliation(s)
- Adam M P Miller
- Department of Psychology, Cornell University, Ithaca, NY 14853, USA
| | - Anna C Serrichio
- Department of Psychology, Cornell University, Ithaca, NY 14853, USA
| | - David M Smith
- Department of Psychology, Cornell University, Ithaca, NY 14853, USA
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36
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de Lima MAX, Baldo MVC, Canteras NS. Revealing a Cortical Circuit Responsive to Predatory Threats and Mediating Contextual Fear Memory. Cereb Cortex 2020; 29:3074-3090. [PMID: 30085040 DOI: 10.1093/cercor/bhy173] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 06/27/2018] [Indexed: 01/12/2023] Open
Abstract
The ventral part of the anteromedial thalamic nucleus (AMv) receives substantial inputs from hypothalamic sites that are highly responsive to a live predator or its odor trace and represents an important thalamic hub for conveying predatory threat information to the cerebral cortex. In the present study, we begin by examining the cortico-amygdalar-hippocampal projections of the main AMv cortical targets, namely, the caudal prelimbic, rostral anterior cingulate, and medial visual areas, as well as the rostral part of the ventral retrosplenial area, one of the main targets of the anterior cingulate area. We observed that these areas form a clear cortical network. Next, we revealed that in animals exposed to a live cat, all of the elements of this circuit presented a differential increase in Fos, supporting the idea of a predator threat-responsive cortical network. Finally, we showed that bilateral cytotoxic lesions in each element of this cortical network did not change innate fear responses but drastically reduced contextual conditioning to the predator-associated environment. Overall, the present findings suggest that predator threat has an extensive representation in the cerebral cortex and revealed a cortical network that is responsive to predatory threats and exerts a critical role in processing fear memory.
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Affiliation(s)
| | - Marcus Vinicius C Baldo
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo; São Paulo, SP, Brazil
| | - Newton Sabino Canteras
- Department of Anatomy, Institute of Biomedical Sciences, University of São Paulo; São Paulo, SP, Brazil
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Abstract
Human and animal imaging studies demonstrated that chronic pain profoundly alters the structure and the functionality of several brain regions. In this article, we conducted a longitudinal and multimodal study to assess how chronic pain affects the brain. Using the spared nerve injury model which promotes both long-lasting mechanical and thermal allodynia/hyperalgesia but also pain-associated comorbidities, we showed that neuropathic pain deeply modified the intrinsic organization of the brain functional network 1 and 2 months after injury. We found that both functional metrics and connectivity of the part A of the retrosplenial granular cortex (RSgA) were significantly correlated with the development of neuropathic pain behaviours. In addition, we found that the functional RSgA connectivity to the subiculum and the prelimbic system are significantly increased in spared nerve injury animals and correlated with peripheral pain thresholds. These brain regions were previously linked to the development of comorbidities associated with neuropathic pain. Using a voxel-based morphometry approach, we showed that neuropathic pain induced a significant increase of the gray matter concentration within the RSgA, associated with a significant activation of both astrocytes and microglial cells. Together, functional and morphological imaging metrics of the RSgA could be used as a predictive biomarker of neuropathic pain.
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Zhang XY, Wang YF, Zheng LJ, Zhang H, Lin L, Lu GM, Zhang LJ. Impacts of AD-Related ABCA7 and CLU Variants on Default Mode Network Connectivity in Healthy Middle-Age Adults. Front Mol Neurosci 2020; 13:145. [PMID: 32848603 PMCID: PMC7412986 DOI: 10.3389/fnmol.2020.00145] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 07/13/2020] [Indexed: 11/23/2022] Open
Abstract
Objective To investigate the impact of Alzheimer’s disease (AD)-related risk gene (ATP-binding cassette A7-ABCA7 and Clusterin-CLU) on the functional connectivity pattern of default mode network (DMN) in healthy middle-age adults. Methods A total of 147 healthy middle-aged volunteers were enrolled in this study. All subjects completed MRI scans, neuropsychological assessments, and AD-related genotyped analysis. All subjects were divided into high, middle and low risk groups according to the score of risk genotypes, which included CLU (rs11136000, rs2279590, rs9331888, and rs9331949) and ABCA7 (rs3764650 and rs4147929). The genetic effects of CLU, ABCA7, and CLU × ABCA7 on DMN functional connectivity pattern were further explored. Moreover, the genetic effect of Apolipoprotein ε4 (APOEε4) was also considered. Finally, correlation analysis was performed between the signals of brain regions with genetic effect and neuropsychological test scores. Results Compared with the low-risk group, the high-risk group of CLU showed decreased functional connectivity in posterior cingulate cortex (PCC) and the left middle frontal cortex (P < 0.05, GRF correction). As for the interaction between the CLU and ABCA7, all the subjects were divided into high, middle, and low risk group; the middle-risk group was divided into CLU and ABCA7-dominated middle-risk group. The function connectivity pattern of DMN among the three or four groups were distributed in the bilateral medial prefrontal cortex (MPFC) and bilateral superior frontal gyrus (SFG) (P < 0.05, GRF correction). When APOEε4 carriers were excluded, the CLU-predominant middle-risk group displayed the decreased functional connectivity in MPFC when compared with the low-risk group, while ABCA7-prodominant middle-risk group displayed decreased functional connectivity in cuneus when compared with the high-risk group (all P < 0.05, GRF correction). The z values of left middle frontal cortex were positively correlated with the scores of Serial Dotting Test (SDT) in high-risk group of CLU, while z values of MPFC and cuneus were positively correlated to the scores of Montreal Cognitive Assessment (MoCA) in low-risk group of three or four groups. Conclusion The functional connectivity of MPFC-PCC might be modulated by the interaction of CLU and ABCA7. Moreover, APOEε4 might be interacted with ABCA7 and CLU modulation in the middle-aged carriers.
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Trask S, Dulka BN, Helmstetter FJ. Age-Related Memory Impairment Is Associated with Increased zif268 Protein Accumulation and Decreased Rpt6 Phosphorylation. Int J Mol Sci 2020; 21:E5352. [PMID: 32731408 PMCID: PMC7432048 DOI: 10.3390/ijms21155352] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 07/23/2020] [Accepted: 07/25/2020] [Indexed: 01/26/2023] Open
Abstract
Aging is associated with cognitive decline, including impairments in the ability to accurately form and recall memories. Some behavioral and brain changes associated with aging are evident as early as middle age, making the understanding of associated neurobiological mechanisms essential to aid in efforts aimed at slowing cognitive decline throughout the lifespan. Here, we found that both 15-month-old and 22-month-old rats showed impaired memory recall following trace fear conditioning. This behavioral deficit was accompanied by increased zif268 protein accumulation relative to 3-month-old animals in the medial prefrontal cortex, the dorsal and ventral hippocampi, the anterior and posterior retrosplenial cortices, the lateral amygdala, and the ventrolateral periaqueductal gray. Elevated zif268 protein levels corresponded with decreases in phosphorylation of the Rpt6 proteasome regulatory subunit, which is indicative of decreased engagement of activity-driven protein degradation. Together, these results identify several brain regions differentially impacted by aging and suggest that the accumulation of proteins associated with memory retrieval, through reduced proteolytic activity, is associated with age-related impairments in memory retention.
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Affiliation(s)
| | | | - Fred J. Helmstetter
- Department of Psychology, The University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, WI 53201, USA; (S.T.); (B.N.D.)
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Opalka AN, Wang DV. Hippocampal efferents to retrosplenial cortex and lateral septum are required for memory acquisition. ACTA ACUST UNITED AC 2020; 27:310-318. [PMID: 32669386 PMCID: PMC7365017 DOI: 10.1101/lm.051797.120] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 06/10/2020] [Indexed: 12/20/2022]
Abstract
Learning and memory involves a large neural network of many brain regions, including the notable hippocampus along with the retrosplenial cortex (RSC) and lateral septum (LS). Previous studies have established that the dorsal hippocampus (dHPC) plays a critical role during the acquisition and retrieval/expression of episodic memories. However, the role of downstream circuitry from the dHPC, including the dHPC-to-RSC and dHPC-to-LS pathways, has come under scrutiny only recently. Here, we used an optogenetic approach with contextual fear conditioning in mice to determine whether the above two pathways are involved in acquisition and expression of contextual fear memory. We found that a selective inhibition of the dHPC neuronal terminals in either the RSC or LS during acquisition impaired subsequent memory performance, suggesting that both the dHPC-to-RSC and dHPC-to-LS pathways play a critical role in memory acquisition. We also selectively inhibited the two dHPC efferent pathways during memory retrieval and found a differential effect on memory performance. These results indicate the intricacies of memory processing and that hippocampal efferents to cortical and subcortical regions may be differentially involved in aspects of physiological and cognitive memory processes.
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Affiliation(s)
- Ashley N Opalka
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129, USA
| | - Dong V Wang
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129, USA
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Dysregulation of protein degradation in the hippocampus is associated with impaired spatial memory during the development of obesity. Behav Brain Res 2020; 393:112787. [PMID: 32603798 DOI: 10.1016/j.bbr.2020.112787] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/26/2020] [Accepted: 06/21/2020] [Indexed: 01/09/2023]
Abstract
Studies have shown that long-term exposure to high fat and other obesogenic diets results in insulin resistance and altered blood brain barrier permeability, dysregulation of intracellular signaling mechanisms, changes in DNA methylation levels and gene expression, and increased oxidative stress and neuroinflammation in the hippocampus, all of which are associated with impaired spatial memory. The ubiquitin-proteasome system controls the majority of protein degradation in cells and is a critical regulator of synaptic plasticity and memory formation. Yet, whether protein degradation in the hippocampus becomes dysregulated following weight gain and is associated with obesity-induced memory impairments is unknown. Here, we used a high fat diet procedure in combination with behavioral and subcellular fractionation protocols and a variety of biochemical assays to determine if ubiquitin-proteasome activity becomes altered in the hippocampus during obesity development and whether this is associated with impaired spatial memory. We found that only 6 weeks of exposure to a high fat diet was sufficient to impair performance on an object location task in rats and resulted in dynamic dysregulation of ubiquitin-proteasome activity in the nucleus and cytoplasm of cells in the hippocampus. Furthermore, these changes in the protein degradation process extended into cortical regions also involved in spatial memory formation. Collectively, these results indicate that weight gain-induced memory impairments may be due to altered ubiquitin-proteasome signaling that occurs during the early stages of obesity development.
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Fournier DI, Monasch RR, Bucci DJ, Todd TP. Retrosplenial cortex damage impairs unimodal sensory preconditioning. Behav Neurosci 2020; 134:198-207. [PMID: 32150422 PMCID: PMC7244381 DOI: 10.1037/bne0000365] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The retrosplenial cortex (RSC) is positioned at the interface between cortical sensory regions and the structures that compose the medial temporal lobe memory system. It has recently been suggested that 1 functional role of the RSC involves the formation of associations between cues in the environment (stimulus-stimulus [S-S] learning; Bucci & Robinson, 2014). This suggestion is based, in part, on the finding that lesions or temporary inactivation of the RSC impair sensory preconditioning. However, all prior studies examining the role of the RSC in sensory preconditioning have used cues from multiple modalities (both visual and auditory stimuli). The purpose of the present experiment was to determine whether the RSC contributes to unimodal sensory preconditioning. In the present study we found that both electrolytic and neurotoxic lesions of the RSC impaired sensory preconditioning with auditory cues. Together with previous experiments, these findings indicate that the RSC contributes to both multisensory and unimodal sensory integration, which suggests a general role for the RSC in linking sensory cues in the environment. (PsycInfo Database Record (c) 2020 APA, all rights reserved).
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Yousuf H, Nye AN, Moyer JR. Heterogeneity of neuronal firing type and morphology in retrosplenial cortex of male F344 rats. J Neurophysiol 2020; 123:1849-1863. [PMID: 32267193 DOI: 10.1152/jn.00577.2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The rodent granular retrosplenial cortex (gRSC) has reciprocal connections to the hippocampus to support fear memories. Although activity-dependent plasticity occurs within the RSC during memory formation, the intrinsic and morphological properties of RSC neurons are poorly understood. The present study used whole-cell recordings to examine intrinsic neuronal firing and morphology of neurons in layer 2/3 (L2/3) and layer 5 (L5) of the gRSC in adult male rats. Five different classifications were observed: regular-spiking (RS), regular-spiking afterdepolarization (RSADP), late-spiking (LS), burst-spiking (BS), and fast-spiking (FS) neurons. RSADP neurons were the most commonly observed neuronal class, identified by their robust spike frequency adaptation and pronounced afterdepolarization (ADP) following an action potential (AP). They also had the most extensive dendritic branching compared with other cell types. LS neurons were predominantly found in L2/3 and exhibited a long delay before onset of their initial AP. They also had reduced dendritic branching compared with other cell types. BS neurons were limited to L5 and generated an initial burst of two or more APs. FS neurons demonstrated sustained firing and little frequency adaptation and were the only nonpyramidal firing type. Relative to adults, RS neurons from juvenile rats (PND 14-30) lacked an ADP and were less excitable. Bath application of group 1 mGluR blockers attenuated the ADP in adult neurons. In other fear-related brain structures, the ADP has been shown to enhance excitability and synaptic plasticity. Thus, understanding cellular mechanisms of the gRSC will provide insight regarding its precise role in memory-related processes across the lifespan.NEW & NOTEWORTHY This is the first study to demonstrate that granular retrosplenial cortical (gRSC) neurons exhibit five distinctive firing types: regular spiking (RS), regular spiking with an afterdepolarization (RSADP), late spiking (LS), burst spiking (BS), and fast spiking (FS). RSADP neurons were the most frequently observed cell type in adult gRSC neurons. Interestingly, RS neurons without an ADP were most common in gRSC neurons of juvenile rats (PND 14-30). Thus, the ADP property, which was previously shown to enhance neuronal excitability, emerges during development.
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Affiliation(s)
- Hanna Yousuf
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin
| | - Andrew N Nye
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin
| | - James R Moyer
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin.,Department of Biological Sciences University of Wisconsin-Milwaukee, Milwaukee, Wisconsin
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Abstract
In this review we briefly outline how lesion studies, temporary inactivation and neural activity assays have helped update functional models of the retrosplenial cortex, a region critical for episodic and spatial memory. We advocate for the continued importance of appropriately designed behavioural studies in the context of novel experimental methods, such as optogenetic and chemogenetic manipulations. At the same time, we caution against the overreliance on any given level of analysis or experimental technique. Complementary, multimodal strategies are required for understanding how the retrosplenial cortex contributes to the formation and storage of memories both at a structural and systems-level.
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Anterior retrosplenial cortex is required for long-term object recognition memory. Sci Rep 2020; 10:4002. [PMID: 32152383 PMCID: PMC7062718 DOI: 10.1038/s41598-020-60937-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 02/19/2020] [Indexed: 01/06/2023] Open
Abstract
The retrosplenial cortex (RSC) is implicated on navigation and contextual memory. Lesions studies showed that the RSC shares functional similarities with the hippocampus (HP). Here we evaluated the role of the anterior RSC (aRSC) in the “what” and “where” components of recognition memory and contrasted it with that of the dorsal HP (dHP). Our behavioral and molecular findings show functional differences between the aRSC and the dHP in recognition memory. The inactivation of the aRSC, but not the dHP, impairs the consolidation and expression of the “what” memory component. In addition, object recognition task is accompanied by c-Fos levels increase in the aRSC. Interestingly, we found that the aRSC is recruited to process the “what” memory component only if it is active during acquisition. In contrast, both the aRSC and dHP are required for encoding the “where” component, which correlates with c-Fos levels increase. Our findings introduce a novel role of the aRSC in recognition memory, processing not only the “where”, but also the “what” memory component.
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Yousuf H, Ehlers VL, Sehgal M, Song C, Moyer JR. Modulation of intrinsic excitability as a function of learning within the fear conditioning circuit. Neurobiol Learn Mem 2019; 167:107132. [PMID: 31821881 DOI: 10.1016/j.nlm.2019.107132] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 11/27/2019] [Indexed: 11/28/2022]
Abstract
Experience-dependent neuronal plasticity is a fundamental substrate of learning and memory. Intrinsic excitability is a form of neuronal plasticity that can be altered by learning and indicates the pattern of neuronal responding to external stimuli (e.g. a learning or synaptic event). Associative fear conditioning is one form of learning that alters intrinsic excitability, reflecting an experience-dependent change in neuronal function. After fear conditioning, intrinsic excitability changes are evident in brain regions that are a critical part of the fear circuit, including the amygdala, hippocampus, retrosplenial cortex, and prefrontal cortex. Some of these changes are transient and/or reversed by extinction as well as learning-specific (i.e. they are not observed in neurons from control animals). This review will explore how intrinsic neuronal excitability changes within brain structures that are critical for fear learning, and it will also discuss evidence promoting intrinsic excitability as a vital mechanism of associative fear memories. This work has raised interesting questions regarding the role of fear learning in changes of intrinsic excitability within specific subpopulations of neurons, including those that express immediate early genes and thus demonstrate experience-dependent activity, as well as in neurons classified as having a specific firing type (e.g. burst-spiking vs. regular-spiking). These findings have interesting implications for how intrinsic excitability can serve as a neural substrate of learning and memory, and suggest that intrinsic plasticity within specific subpopulations of neurons may promote consolidation of the memory trace in a flexible and efficient manner.
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Affiliation(s)
- Hanna Yousuf
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA
| | - Vanessa L Ehlers
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA
| | - Megha Sehgal
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA
| | - Chenghui Song
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA
| | - James R Moyer
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA; Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, USA.
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Todd TP, Fournier DI, Bucci DJ. Retrosplenial cortex and its role in cue-specific learning and memory. Neurosci Biobehav Rev 2019; 107:713-728. [PMID: 31055014 PMCID: PMC6906080 DOI: 10.1016/j.neubiorev.2019.04.016] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 04/22/2019] [Accepted: 04/24/2019] [Indexed: 10/26/2022]
Abstract
The retrosplenial cortex (RSC) contributes to spatial navigation, as well as contextual learning and memory. However, a growing body of research suggests that the RSC also contributes to learning and memory for discrete cues, such as auditory or visual stimuli. In this review, we summarize and assess the Pavlovian and instrumental conditioning experiments that have examined the role of the RSC in cue-specific learning and memory. We use the term cue-specific to refer to these putatively non-spatial conditioning paradigms that involve discrete cues. Although these paradigms emphasize behavior related to cue presentations, we note that cue-specific learning and memory always takes place against a background of contextual stimuli. We review multiple ways by which contexts can influence responding to discrete cues and suggest that RSC contributions to cue-specific learning and memory are intimately tied to contextual learning and memory. Indeed, although the RSC is involved in several forms of cue-specific learning and memory, we suggest that many of these can be linked to processing of contextual stimuli.
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Affiliation(s)
- Travis P Todd
- Dartmouth College, Department of Psychological and Brain Sciences, 6207 Moore Hall, NH, 03755, USA.
| | - Danielle I Fournier
- Dartmouth College, Department of Psychological and Brain Sciences, 6207 Moore Hall, NH, 03755, USA
| | - David J Bucci
- Dartmouth College, Department of Psychological and Brain Sciences, 6207 Moore Hall, NH, 03755, USA
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Sigwald EL, Bignante EA, de Olmos S, Lorenzo A. Fear-context association during memory retrieval requires input from granular to dysgranular retrosplenial cortex. Neurobiol Learn Mem 2019; 163:107036. [PMID: 31201928 DOI: 10.1016/j.nlm.2019.107036] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 05/16/2019] [Accepted: 06/12/2019] [Indexed: 01/10/2023]
Abstract
The contribution of the granular (area 29, A29) and dysgranular (area 30, A30) subdivisions of the retrosplenial cortex (RSC) to contextual fear memory (CFM) retrieval remains elusive. Here, intact and orchiectomized (ORC) male rats received an intraperitoneal (I.P.) injection of saline (control) or 5 mg/Kg MK801 after training and memory formation. In ORC, but not in intact males, this MK801 treatment selectively induces overt loss of neurons in layers IV-Va of A29 (A29MK801 neurons) (Sigwald et al., 2016). Compared to ORC-saline, ORC-MK801 rats showed impaired CFM retrieval in an A-B-A design for contextual fear conditioning (CFC), however context recognition was not affected. In ORC-MK801 rats, neither novel object recognition nor object-in-context discrimination were impaired, further indicating that A29MK801 neurons are not required for contextual recognition. Elevated plus maze test showed that anxiety-like behavior was not affected in ORC-MK801 animals, suggesting that loss of A29MK801 neurons does not affect the emotional state that could impair freezing during test. Importantly, in a sensory preconditioning test, higher order CFM retrieval was abolished in ORC-MK801, but not in male-MK801. Collectively, these observations indicate that A29MK801 neurons are critically required for retrieving fear-context association. For dissecting the anatomofunctional contribution of A29MK801 neurons to CFM retrieval, expression of c-Fos and Egr-1 was used to map brain-wide neuronal activity. In control male rats CFC and CFM retrieval was associated with significant enhancement of both proteins in limbic structures and A30, but not in A29, suggesting that neurons in A30 and limbic structures encode and store the associative experience. Notably, in ORC but not in intact males, MK801 impairs CFM retrieval and expression of c-Fos and Egr-1 proteins in A30, without affecting their expression in limbic structures. Thus, the loss of A29MK801 neurons after CFM formation precludes activation of associative neurons in A30, impairing CFM recall. FluoroGold retrograde track-tracing confirmed that A29MK801 neurons project to A30. Silver staining provide evidence that MK801 in ORC rats induces axonal deafferentation of A29MK801 neuron in A30. Collectively, our experiments provide the first evidence that A30 neurons participate in encoding and storing CFM while A29 is required for their activation during recall.
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Affiliation(s)
- Eric L Sigwald
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Friuli 2434, 5016 Córdoba, Argentina
| | - Elena A Bignante
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Friuli 2434, 5016 Córdoba, Argentina; Instituto Universitario de Ciencias Biomédicas de Córdoba (IUCBC), Córdoba, Argentina
| | - Soledad de Olmos
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Friuli 2434, 5016 Córdoba, Argentina
| | - Alfredo Lorenzo
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Friuli 2434, 5016 Córdoba, Argentina; Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Farmacología, Córdoba, Argentina.
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Fournier DI, Todd TP, Bucci DJ. Permanent damage or temporary silencing of retrosplenial cortex impairs the expression of a negative patterning discrimination. Neurobiol Learn Mem 2019; 163:107033. [PMID: 31173918 DOI: 10.1016/j.nlm.2019.107033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 06/03/2019] [Accepted: 06/03/2019] [Indexed: 12/18/2022]
Abstract
The retrosplenial cortex (RSC) is positioned at the interface between cortical sensory regions and the hippocampal/parahippocampal memory system. As such, it has been theorized that RSC may have a fundamental role in linking sensory stimuli together in the service of forming complex representations. To test this, three experiments were carried out to determine the effects of RSC damage or temporary inactivation on learning or performing a negative patterning discrimination. In this procedure, two conditioned stimuli are reinforced when they are presented individually (i.e., stimulus elements) but are non-reinforced when they are presented simultaneously as a compound stimulus. Normal rats successfully discriminate between the two types of trials as evidenced by more responding to the elements compared to the compound stimulus. This is thought to reflect the formation of a configural representation of the compound stimulus; that is, the two cues are linked together in such a fashion that the compound stimulus is a wholly different, unique stimulus. Permanent lesions of RSC made prior to training (Experiment 1) had no effect on learning the discrimination. However, lesions (Experiment 2) or temporary chemogenetic inactivation (Experiment 3) of RSC made after training impaired subsequent performance of the discrimination. We argue that this pattern of results indicates that RSC may normally be involved in forming the configural representations manifested in negative patterning, but that absent the RSC, other brain systems or structures can compensate sufficiently to result in normal behavior.
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Affiliation(s)
- Danielle I Fournier
- Program in Experimental and Molecular Medicine, Geisel School of Medicine at Dartmouth, USA
| | - Travis P Todd
- Department of Psychological and Brain Sciences, Dartmouth College, USA
| | - David J Bucci
- Program in Experimental and Molecular Medicine, Geisel School of Medicine at Dartmouth, USA; Department of Psychological and Brain Sciences, Dartmouth College, USA.
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Fournier DI, Eddy MC, DeAngeli NE, Huszár R, Bucci DJ. Retrosplenial cortex damage produces retrograde and anterograde context amnesia using strong fear conditioning procedures. Behav Brain Res 2019; 369:111920. [PMID: 31039379 DOI: 10.1016/j.bbr.2019.111920] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 04/12/2019] [Accepted: 04/18/2019] [Indexed: 10/26/2022]
Abstract
Contextual fear conditioning relies upon a network of cortical and subcortical structures, including the hippocampus and the retrosplenial cortex (RSC). However, the contribution of the hippocampus is parameter-dependent. For example, with "weak" training procedures, lesions of the hippocampus produce both retrograde and anterograde context amnesia. However, with "strong" training procedures (e.g., more trials and/or higher levels of footshock), lesions of the hippocampus produce retrograde context amnesia but not anterograde amnesia (Wiltgen et al., 2006). Likewise, prior studies have shown that with weak training, RSC lesions produce both retrograde and anterograde context amnesia (Keene & Bucci, 2008). The purpose of the current study was to examine the effects of RSC damage on contextual fear conditioning following strong training. In Experiment 1, lesions of the RSC resulted in both retrograde and anterograde context amnesia following strong training using the same unsignaled fear conditioning procedures described by Wiltgen et al. (2006). In Experiment 2, using a signaled fear conditioning procedure, we replicated these effects on context memory observing both retrograde and anterograde context amnesia. In contrast, there were no lesion effects on tone-fear memory. Thus, unlike lesions of the hippocampus, lesions of RSC produce both retrograde and anterograde context amnesia even when rats undergo strong fear conditioning. These findings suggest that the RSC has an essential role in contextual fear conditioning and that other systems or pathways are unable to compensate for the loss of RSC function.
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Affiliation(s)
- Danielle I Fournier
- Program in Experimental and Molecular Medicine, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Meghan C Eddy
- Department of Psychological and Brain Sciences, Dartmouth College, Hanover, NH, USA
| | - Nicole E DeAngeli
- Department of Psychological and Brain Sciences, Dartmouth College, Hanover, NH, USA
| | - Roman Huszár
- Department of Psychological and Brain Sciences, Dartmouth College, Hanover, NH, USA
| | - David J Bucci
- Program in Experimental and Molecular Medicine, Geisel School of Medicine at Dartmouth, Hanover, NH, USA; Department of Psychological and Brain Sciences, Dartmouth College, Hanover, NH, USA.
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