1
|
Steiner NL, Purohit DC, Tiefenthaler CM, Mandyam CD. Abstinence and Fear Experienced during This Period Produce Distinct Cortical and Hippocampal Adaptations in Alcohol-Dependent Rats. Brain Sci 2024; 14:431. [PMID: 38790410 PMCID: PMC11118749 DOI: 10.3390/brainsci14050431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 04/14/2024] [Accepted: 04/20/2024] [Indexed: 05/26/2024] Open
Abstract
Previous studies demonstrate that ethanol dependence induced by repeating cycles of chronic intermittent ethanol vapor exposure (CIE) followed by protracted abstinence produces significant gray matter damage via myelin dysfunction in the rodent medial prefrontal cortex (mPFC) and alterations in neuronal excitability in the mPFC and the dentate gyrus (DG) of the hippocampus. Specifically, abstinence-induced neuroadaptations have been associated with persistent elevated relapse to drinking. The current study evaluated the effects of forced abstinence for 1 day (d), 7 d, 21 d, and 42 d following seven weeks of CIE on synaptic plasticity proteins in the mPFC and DG. Immunoblotting revealed reduced expression of CaMKII in the mPFC and enhanced expression of GABAA and CaMKII in the DG at the 21 d time point, and the expression of the ratio of GluN2A/2B subunits did not change at any of the time points studied. Furthermore, cognitive performance via Pavlovian trace fear conditioning (TFC) was evaluated in 3 d abstinent rats, as this time point is associated with negative affect. In addition, the expression of the ratio of GluN2A/2B subunits and a 3D structural analysis of neurons in the mPFC and DG were evaluated in 3 d abstinent rats. Behavioral analysis revealed faster acquisition of fear responses and reduced retrieval of fear memories in CIE rats compared to controls. TFC produced hyperplasticity of pyramidal neurons in the mPFC under control conditions and this effect was not evident or blunted in abstinent rats. Neurons in the DG were unaltered. TFC enhanced the GluN2A/2B ratio in the mPFC and reduced the ratio in the DG and was not altered by abstinence. These findings indicate that forced abstinence from CIE produces distinct and divergent alterations in plasticity proteins in the mPFC and DG. Fear learning-induced changes in structural plasticity and proteins contributing to it were more profound in the mPFC during forced abstinence.
Collapse
Affiliation(s)
- Noah L. Steiner
- VA San Diego Healthcare System, San Diego, CA 92161, USA; (N.L.S.)
| | | | - Casey M. Tiefenthaler
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, San Diego, CA 92093, USA;
| | - Chitra D. Mandyam
- VA San Diego Healthcare System, San Diego, CA 92161, USA; (N.L.S.)
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, San Diego, CA 92093, USA;
- Department of Anesthesiology, University of California San Diego, San Diego, CA 92093, USA
| |
Collapse
|
2
|
Vasudevan K, Hassell JE, Maren S. Hippocampal Engrams and Contextual Memory. ADVANCES IN NEUROBIOLOGY 2024; 38:45-66. [PMID: 39008010 DOI: 10.1007/978-3-031-62983-9_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
Memories are not formed in a vacuum and often include rich details about the time and place in which events occur. Contextual stimuli promote the retrieval of events that have previously occurred in the encoding context and limit the retrieval of context-inappropriate information. Contexts that are associated with traumatic or harmful events both directly elicit fear and serve as reminders of aversive events associated with trauma. It has long been appreciated that the hippocampus is involved in contextual learning and memory and is central to contextual fear conditioning. However, little is known about the underlying neuronal mechanisms underlying the encoding and retrieval of contextual fear memories. Recent advancements in neuronal labeling methods, including activity-dependent tagging of cellular ensembles encoding memory ("engrams"), provide unique insight into the neural substrates of memory in the hippocampus. Moreover, these methods allow for the selective manipulation of memory ensembles. Attenuating or erasing fear memories may have considerable therapeutic value for patients with post-traumatic stress disorder or other trauma- or stressor-related conditions. In this chapter, we review the role of the hippocampus in contextual fear conditioning in rodents and explore recent work implicating hippocampal ensembles in the encoding and retrieval of aversive memories.
Collapse
Affiliation(s)
- Krithika Vasudevan
- Department of Psychological and Brain Sciences and Institute for Neuroscience, Texas A&M University, College Station, TX, USA
| | - James E Hassell
- Department of Psychological and Brain Sciences and Institute for Neuroscience, Texas A&M University, College Station, TX, USA
| | - Stephen Maren
- Department of Psychological and Brain Sciences and Institute for Neuroscience, Texas A&M University, College Station, TX, USA.
| |
Collapse
|
3
|
Namkung H, Thomas KL, Hall J, Sawa A. Parsing neural circuits of fear learning and extinction across basic and clinical neuroscience: Towards better translation. Neurosci Biobehav Rev 2022; 134:104502. [PMID: 34921863 DOI: 10.1016/j.neubiorev.2021.12.025] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 12/13/2021] [Accepted: 12/14/2021] [Indexed: 12/22/2022]
Abstract
Over the past decades, studies of fear learning and extinction have advanced our understanding of the neurobiology of threat and safety learning. Animal studies can provide mechanistic/causal insights into human brain regions and their functional connectivity involved in fear learning and extinction. Findings in humans, conversely, may further enrich our understanding of neural circuits in animals by providing macroscopic insights at the level of brain-wide networks. Nevertheless, there is still much room for improvement in translation between basic and clinical research on fear learning and extinction. Through the lens of neural circuits, in this article, we aim to review the current knowledge of fear learning and extinction in both animals and humans, and to propose strategies to fill in the current knowledge gap for the purpose of enhancing clinical benefits.
Collapse
Affiliation(s)
- Ho Namkung
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA; Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
| | - Kerrie L Thomas
- Neuroscience and Mental Health Research Institute, Cardiff University, Cardiff, UK; School of Biosciences, Cardiff University, Cardiff, UK
| | - Jeremy Hall
- Neuroscience and Mental Health Research Institute, Cardiff University, Cardiff, UK; School of Medicine, Cardiff University, Cardiff, UK
| | - Akira Sawa
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA; Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA; Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA; Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA; Department of Mental Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, 21287, USA.
| |
Collapse
|
4
|
The Medial Prefrontal Cortex and Fear Memory: Dynamics, Connectivity, and Engrams. Int J Mol Sci 2021; 22:ijms222212113. [PMID: 34830009 PMCID: PMC8619965 DOI: 10.3390/ijms222212113] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/02/2021] [Accepted: 11/03/2021] [Indexed: 01/08/2023] Open
Abstract
It is becoming increasingly apparent that long-term memory formation relies on a distributed network of brain areas. While the hippocampus has been at the center of attention for decades, it is now clear that other regions, in particular the medial prefrontal cortex (mPFC), are taking an active part as well. Recent evidence suggests that the mPFC-traditionally implicated in the long-term storage of memories-is already critical for the early phases of memory formation such as encoding. In this review, we summarize these findings, relate them to the functional importance of the mPFC connectivity, and discuss the role of the mPFC during memory consolidation with respect to the different theories of memory storage. Owing to its high functional connectivity to other brain areas subserving memory formation and storage, the mPFC emerges as a central hub across the lifetime of a memory, although much still remains to be discovered.
Collapse
|
5
|
Sarver DC, Xu C, Cheng Y, Terrillion CE, Wong GW. CTRP4 ablation impairs associative learning and memory. FASEB J 2021; 35:e21910. [PMID: 34610176 DOI: 10.1096/fj.202100733rr] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 08/12/2021] [Accepted: 08/24/2021] [Indexed: 11/11/2022]
Abstract
C1q/TNF-related protein (CTRP) family comprises fifteen highly conserved secretory proteins with diverse central and peripheral functions. In zebrafish, mouse, and human, CTRP4 is most highly expressed in the brain. We previously showed that CTRP4 is a metabolically responsive regulator of food intake and energy balance, and mice lacking CTRP4 exhibit sexually dimorphic changes in ingestive behaviors and systemic metabolism. Recent single-cell RNA sequencing also revealed Ctrp4/C1qtnf4 expression in diverse neuronal cell types across distinct anatomical brain regions, hinting at additional roles in the central nervous system not previously characterized. To uncover additional central functions of CTRP4, we subjected Ctrp4 knockout (KO) mice to a battery of behavioral tests. Relative to wild-type (WT) littermates, loss of CTRP4 does not alter exploratory, anxiety-, or depressive-like behaviors, motor function and balance, sensorimotor gating, novel object recognition, and spatial memory. While pain-sensing mechanisms in response to thermal stress and mild shock are intact, both male and female Ctrp4 KO mice have increased sensitivity to pain induced by higher-level shock, suggesting altered nociceptive function. Importantly, CTRP4 deficiency impairs hippocampal-dependent associative learning and memory as assessed by trace fear conditioning paradigm. This deficit is sex-dependent, affects only female mice, and is associated with altered expression of learning and memory genes (Arc, c-fos, and Pde4d) in the hippocampus and cortex. Altogether, our behavioral and gene expression analyses have uncovered novel aspects of the CTRP4 function and provided a physiological context to further investigate its mechanism of action in the central and peripheral nervous system.
Collapse
Affiliation(s)
- Dylan C Sarver
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Cheng Xu
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Yi Cheng
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Chantelle E Terrillion
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - G William Wong
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| |
Collapse
|
6
|
Staples MC, Herman MA, Lockner JW, Avchalumov Y, Kharidia KM, Janda KD, Roberto M, Mandyam CD. Isoxazole-9 reduces enhanced fear responses and retrieval in ethanol-dependent male rats. J Neurosci Res 2021; 99:3047-3065. [PMID: 34496069 PMCID: PMC10112848 DOI: 10.1002/jnr.24932] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 06/30/2021] [Accepted: 07/12/2021] [Indexed: 12/13/2022]
Abstract
Plasticity in the dentate gyrus (DG) is strongly influenced by ethanol, and ethanol experience alters long-term memory consolidation dependent on the DG. However, it is unclear if DG plasticity plays a role in dysregulation of long-term memory consolidation during abstinence from chronic ethanol experience. Outbred male Wistar rats experienced 7 weeks of chronic intermittent ethanol vapor exposure (CIE). Seventy-two hours after CIE cessation, CIE and age-matched ethanol-naïve Air controls experienced auditory trace fear conditioning (TFC). Rats were tested for cue-mediated retrieval in the fear context either twenty-four hours (24 hr), ten days (10 days), or twenty-one days (21 days) later. CIE rats showed enhanced freezing behavior during TFC acquisition compared to Air rats. Air rats showed significant fear retrieval, and this behavior did not differ at the three time points. In CIE rats, fear retrieval increased over time during abstinence, indicating an incubation in fear responses. Enhanced retrieval at 21 days was associated with reduced structural and functional plasticity of ventral granule cell neurons (GCNs) and reduced expression of synaptic proteins important for neuronal plasticity. Systemic treatment with the drug Isoxazole-9 (Isx-9; small molecule that stimulates DG plasticity) during the last week and a half of CIE blocked altered acquisition and retrieval of fear memories in CIE rats during abstinence. Concurrently, Isx-9 modulated the structural and functional plasticity of ventral GCNs and the expression of synaptic proteins in the ventral DG. These findings identify that abstinence-induced disruption of fear memory consolidation occurs via altered plasticity within the ventral DG, and that Isx-9 prevented these effects.
Collapse
Affiliation(s)
| | - Melissa A Herman
- Department of Pharmacology, Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Jonathan W Lockner
- Departments of Chemistry and Immunology, Scripps Research, La Jolla, CA, USA
| | | | | | - Kim D Janda
- Departments of Chemistry and Immunology, Scripps Research, La Jolla, CA, USA
| | - Marisa Roberto
- Departments of Molecular Medicine and Neuroscience, Scripps Research, La Jolla, CA, USA
| | - Chitra D Mandyam
- VA San Diego Healthcare System, San Diego, CA, USA.,Department of Anesthesiology, University of California San Diego, San Diego, CA, USA
| |
Collapse
|
7
|
Knox D, Della Valle R, Mohammadmirzaei N, Shultz B, Biddle M, Farkash A, Chamness M, Moulton E. PI3K-Akt Signaling in the Basolateral Amygdala Facilitates Traumatic Stress Enhancements in Fear Memory. Int J Neuropsychopharmacol 2020; 24:229-238. [PMID: 33151288 PMCID: PMC7968623 DOI: 10.1093/ijnp/pyaa083] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 10/02/2020] [Accepted: 10/29/2020] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND A core symptom of posttraumatic stress disorder is persistent fear memory, which can be defined as fear memory that is resistant to updating, inhibition, or extinction. posttraumatic stress disorder emerges after traumatic stress exposure, but neurobiological mechanisms via which traumatic stress leads to persistent fear memory are not well defined. Akt signaling within the amygdala (Amy) is enhanced with traumatic stress, and phosphatidylinositol kinase 3 (PI3K) activation of Akt within the basolateral Amy (BLA) has been implicated as critical to fear memory formation. These findings raise the possibility that traumatic stress enhances PI3K→Akt signaling in the BLA, which leads to persistent fear memory. METHODS To test this hypothesis, rats were exposed to traumatic stress using the single prolonged stress model, and changes in Akt phosphorylation were assayed in the Amy at 0 and 30 minutes after fear conditioning (FC). In a separate experiment, we inhibited PI3K→Akt signaling in the BLA prior to FC and observed the effect this had on acquisition, expression, and extinction of FC in stressed and control rats. RESULTS Enhanced Akt phosphorylation in the Amy at both time points was observed in stressed rats, but not in control rats. PI3K→Akt inhibition in the BLA had no effect on freezing in control rats but decreased freezing during extinction training and testing in stressed rats. CONCLUSION These findings suggest that PI3K→Akt signaling in the BLA could be a mechanism via which traumatic stress leads to fear memory that is resistant to extinction.
Collapse
Affiliation(s)
- Dayan Knox
- Department of Psychological and Brain Sciences, University of Delaware, Newark, Delaware, USA,Correspondence: Dayan Knox, PhD, 217 Wolf Hall, Department of Psychological and Brain Sciences, University of Delaware, Newark, DE 19716 ()
| | - Rebecca Della Valle
- Department of Psychological and Brain Sciences, University of Delaware, Newark, Delaware, USA
| | - Negin Mohammadmirzaei
- Department of Psychological and Brain Sciences, University of Delaware, Newark, Delaware, USA
| | - Brianna Shultz
- Department of Psychological and Brain Sciences, University of Delaware, Newark, Delaware, USA
| | - Matt Biddle
- Department of Psychological and Brain Sciences, University of Delaware, Newark, Delaware, USA
| | - Abigail Farkash
- Department of Psychological and Brain Sciences, University of Delaware, Newark, Delaware, USA
| | - Marisa Chamness
- Department of Psychological and Brain Sciences, University of Delaware, Newark, Delaware, USA
| | - Emily Moulton
- Department of Psychological and Brain Sciences, University of Delaware, Newark, Delaware, USA
| |
Collapse
|
8
|
Ehlers VL, Smies CW, Moyer JR. Apoaequorin differentially modulates fear memory in adult and aged rats. Brain Behav 2020; 10:e01832. [PMID: 32945630 PMCID: PMC7667302 DOI: 10.1002/brb3.1832] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 08/11/2020] [Accepted: 08/18/2020] [Indexed: 01/06/2023] Open
Abstract
INTRODUCTION Cognitive deficits during aging are pervasive across species and learning paradigms. One of the major mechanisms thought to play a role in age-related memory decline is dysregulated calcium (Ca2+ ) homeostasis. Aging is associated with impaired function of several calcium-regulatory mechanisms, including calcium-binding proteins that normally support intracellular Ca2+ regulation. This age-related calcium-binding protein dysfunction and changes in expression lead to disrupted maintenance of intracellular Ca2+ , thus contributing to memory decline. Other work has found that age-related cognitive deficits can be mitigated by either blocking Ca2+ entry into the cytosol or preventing its release from intracellular Ca2+ stores. However, the effect of calcium-binding protein administration on cognitive function during aging is not well-understood. Our laboratory has previously shown that the calcium-binding protein apoaequorin (AQ) is neuroprotective during oxygen-glucose deprivation, a model of in vitro ischemia characterized by calcium-induced excitotoxicity. The current experiments assessed the effect of direct dorsal hippocampal AQ infusion on trace and context fear memory in adult and aged rats. METHODS Adult (3-6 months) and aged (22-26 months) male F344 rats were randomly assigned to different experimental infusion groups before undergoing trace fear conditioning and testing. In experiment 1, rats received bilateral dorsal hippocampal infusions of either vehicle or AQ (4% w/v) 24 hr before trace fear conditioning. In experiment 2, rats received bilateral dorsal hippocampal infusions of either vehicle or 4% AQ 1 hr before trace fear conditioning and 1 hr before testing. RESULTS Aged rats displayed impaired trace and context fear memory. While a single AQ infusion 24 hr before trace fear conditioning was insufficient to rescue age-related trace fear memory deficits, AQ infusion 1 hr before both conditioning and testing abolished age-related context fear memory deficits. CONCLUSIONS These results suggest that intrahippocampal infusion of AQ may reverse aging-related deficits in hippocampus-dependent context fear memory.
Collapse
Affiliation(s)
- Vanessa L Ehlers
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Chad W Smies
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - James R Moyer
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, USA.,Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| |
Collapse
|
9
|
Noh K, Park JC, Han JS, Lee SJ. From Bound Cells Comes a Sound Mind: The Role of Neuronal Growth Regulator 1 in Psychiatric Disorders. Exp Neurobiol 2020; 29:1-10. [PMID: 32122104 PMCID: PMC7075657 DOI: 10.5607/en.2020.29.1.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 02/23/2020] [Accepted: 02/25/2020] [Indexed: 12/21/2022] Open
Abstract
Cell-to-cell adhesion is important for maintenance of brain structure and function. Abnormal neuronal cell adhesion and loss of its connectivity are considered a main cause of psychiatric disorders such as major depressive disorder (MDD). Various cell adhesion molecules (CAMs) are involved in neuronal cell adhesions and thereby affect brain functions such as learning and memory, cognitive functions, and psychiatric functions. Compared with other CAMs, neuronal growth regulator 1 (Negr1) has a distinct functioning mechanism in terms of its cross-talk with cytokine receptor signaling. Negr1 is a member of the immunoglobulin LON (IgLON) family of proteins and is involved in neuronal outgrowth, dendritic arborization, and synapse formation. In humans, Negr1 is a risk gene for obesity based on a genome-wide association study. More recently, accumulating evidence supports that it also plays a critical role in psychiatric disorders. In this review, we discuss the recent findings on the role of Negr1 in MDD, focusing on its regulatory mechanism. We also provide evidence of putative involvement of Negr1 in other psychiatric disorders based on the novel behavioral phenotypes of Negr1 knockout mice.
Collapse
Affiliation(s)
- Kyungchul Noh
- Department of Physiology and Neuroscience, Dental Research Institute, Seoul National University School of Dentistry, Seoul 08826, Korea
| | - Jung-Cheol Park
- Department of Biological Science, Konkuk University, Seoul 05029, Korea
| | - Jung-Soo Han
- Department of Biological Science, Konkuk University, Seoul 05029, Korea
| | - Sung Joong Lee
- Department of Physiology and Neuroscience, Dental Research Institute, Seoul National University School of Dentistry, Seoul 08826, Korea
| |
Collapse
|
10
|
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.
Collapse
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.
| |
Collapse
|
11
|
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: 48] [Impact Index Per Article: 9.6] [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.
Collapse
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
| |
Collapse
|
12
|
Shu SY, Jiang G, Zheng Z, Ma L, Wang B, Zeng Q, Li H, Tan S, Liu B, Chan WY, Wu S, Zhu C, Li C, Wang P, Wu JY. A New Neural Pathway from the Ventral Striatum to the Nucleus Basalis of Meynert with Functional Implication to Learning and Memory. Mol Neurobiol 2019; 56:7222-7233. [PMID: 31001802 PMCID: PMC6728281 DOI: 10.1007/s12035-019-1588-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 03/27/2019] [Indexed: 11/30/2022]
Abstract
The cholinergic neurons in the nucleus basalis of Meynert (NBM) are among the first group of neurons known to become degenerated in Alzheimer’s disease, and thus the NBM is proposed to be involved in learning and memory. The marginal division (MrD) of the striatum is a newly discovered subdivision at the ventromedial border of the mammalian striatum and is considered to be one part of the ventral striatum involved in learning and memory. The present study provided evidence to support the hypothesis that the MrD and the NBM were structurally connected at cellular and subcellular levels with functional implications in learning and memory. First, when wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) was stereotaxically injected into the NBM, fusiform neurons in the MrD were retrogradely labeled with WGA-HRP gray-blue particles and some of them were double stained in brown color by AchE staining method. Thus, cholinergic neurons of the MrD were shown to project to the neurons in the NBM. Second, in anterograde tract-tracing experiments where WGA-HRP was injected to the MrD, the labeled WGA-HRP was found to be anterogradely transported in axons from the MrD to the synaptic terminals with dendrites, axons, and perikaryons of the cholinergic neurons in the NBM when observed under an electronic microscope, indicating reciprocal structural connections between the MrD and the NBM. Third, when bilateral lesions of the MrD were injured with kainic acid in rats, degenerative terminals were observed in synapses of the NBM by an electronic microscope and severe learning and memory deficiency was found in these rats by the Y-maze behavioral test. Our results suggest reciprocal cholinergic connections between the MrD of the ventral striatum and the NBM, and implicate a role of the MrD-NBM pathway in learning and memory. The efferent fibers of cholinergic neurons in the NBM mainly project to the cortex, and severe reduction of the cholinergic innervation in the cortex is the common feature of Alzheimer’s patients. The newly discovered cholinergic neural pathway between the MrD of the ventral striatum and the NBM is supposed involved in the memory circuitries of the brain and probably might play a role in the pathogenesis of the Alzheimer’s disease.
Collapse
Affiliation(s)
- Si Yun Shu
- Pediatric Center, Zhujiang Hospital of the Southern Medical University, A- 3103, Building 39, No. 253 Gong-ye Road, Haizhu District, Guangzhou, 510280 Guangdong China
| | - Gang Jiang
- Department of Ear, Nose and Throat, Zhujiang Hospital of the Southern Medical University, Guangzhou, 510282 Guangdong China
| | - Zhaocong Zheng
- Department of Neurosurgery, Fuzhou Central Hospital of Nanjing Military Region, Fuzhou, 350025 Fujian China
| | - Lin Ma
- Department of Radiology, General Hospital of People’s Liberation Army, Beijing, 100853 China
| | - Bin Wang
- Pediatric Center, Zhujiang Hospital of the Southern Medical University, A- 3103, Building 39, No. 253 Gong-ye Road, Haizhu District, Guangzhou, 510280 Guangdong China
| | - Qiyi Zeng
- Pediatric Center, Zhujiang Hospital of the Southern Medical University, A- 3103, Building 39, No. 253 Gong-ye Road, Haizhu District, Guangzhou, 510280 Guangdong China
| | - Hong Li
- Pediatric Center, Zhujiang Hospital of the Southern Medical University, A- 3103, Building 39, No. 253 Gong-ye Road, Haizhu District, Guangzhou, 510280 Guangdong China
| | - Shen Tan
- Department of Neurology, Zhujiang Hospital of Southern Medical University, Guangzhou, 510282 Guangdong China
| | - Bin Liu
- Emergency Department, Zhujiang Hospital of Southern Medical University, Guangzhou, 510282 Guangdong China
| | - Wood Yee Chan
- School of Biomedical Sciences, Faculty of Medicine, Chinese University of Hong Kong, Shatin, Hong Kong
| | - Sheng Wu
- Nanjing Junqu Hangzhou Sanatorium, 5 Long-jin Road, Hangzhou, 310007 China
| | - Chunhua Zhu
- Nanjing Junqu Hangzhou Sanatorium, 5 Long-jin Road, Hangzhou, 310007 China
| | - Changke Li
- Anesthesia Department of Yue-Bei People Hospital, Shaoguan City, 512026 Guangdong China
| | - Peng Wang
- The Fifth Affiliated Hospital of Southern Medical University, Guangzhou, 510900 China
| | - Jang-Yen Wu
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431 USA
| |
Collapse
|
13
|
Quillfeldt JA. Temporal Flexibility of Systems Consolidation and the Synaptic Occupancy/Reset Theory (SORT): Cues About the Nature of the Engram. Front Synaptic Neurosci 2019; 11:1. [PMID: 30814946 PMCID: PMC6381034 DOI: 10.3389/fnsyn.2019.00001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 01/14/2019] [Indexed: 11/24/2022] Open
Abstract
The ability to adapt to new situations involves behavioral changes expressed either from an innate repertoire, or by acquiring experience through memory consolidation mechanisms, by far a much richer and flexible source of adaptation. Memory formation consists of two interrelated processes that take place at different spatial and temporal scales, Synaptic Consolidation, local plastic changes in the recruited neurons, and Systems Consolidation, a process of gradual reorganization of the explicit/declarative memory trace between hippocampus and the neocortex. In this review, we summarize some converging experimental results from our lab that support a normal temporal framework of memory systems consolidation as measured both from the anatomical and the psychological points of view, and propose a hypothetical model that explains these findings while predicting other phenomena. Then, the same experimental design was repeated interposing additional tasks between the training and the remote test to verify for any interference: we found that (a) when the animals were subject to a succession of new learnings, systems consolidation was accelerated, with the disengagement of the hippocampus taking place before the natural time point of this functional switch, but (b) when a few reactivation sessions reexposed the animal to the training context without the shock, systems consolidation was delayed, with the hippocampus prolonging its involvement in retrieval. We hypothesize that new learning recruits from a fixed number of plastic synapses in the CA1 area to store the engram index, while reconsolidation lead to a different outcome, in which additional synapses are made available. The first situation implies the need of a reset mechanism in order to free synapses needed for further learning, and explains the acceleration observed under intense learning activity, while the delay might be explained by a different process, able to generate extra free synapses: depending on the cognitive demands, it deals either with a fixed or a variable pool of available synapses. The Synaptic Occupancy/Reset Theory (SORT) emerged as an explanation for the temporal flexibility of systems consolidation, to encompass the two different dynamics of explicit memories, as well as to bridge both synaptic and systems consolidation in one single mechanism.
Collapse
Affiliation(s)
- Jorge Alberto Quillfeldt
- Psychobiology and Neurocomputation Lab, Department of Biophysics, Institute of Biosciences, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.,Neurosciences Graduate Program, Institute of Basic Health Sciences, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.,Department of Psychology, McGill University, Montreal, QC, Canada
| |
Collapse
|
14
|
Neonatal ethanol exposure impairs long-term context memory formation and prefrontal immediate early gene expression in adolescent rats. Behav Brain Res 2018; 359:386-395. [PMID: 30447241 DOI: 10.1016/j.bbr.2018.11.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 10/19/2018] [Accepted: 11/13/2018] [Indexed: 11/21/2022]
Abstract
Fetal alcohol exposure leads to severe disruptions in learning and memory involving the hippocampus and prefrontal cortex in humans. Animal model research on FASD has documented impairment of hippocampal neuroanatomy and function but animal studies of cognition involving the prefrontal cortex are sparse. We have found that a variant of contextual fear conditioning in which both the hippocampus and prefrontal cortex is required, the Context Preexposure Facilitation Effect (CPFE), is particularly sensitive to neurobehavioral disruption caused by neonatal ethanol exposure during the third trimester equivalent of human pregnancy in the rat (i.e., PD4-9). In the CPFE, learning about the context, acquiring a context-shock association, and retrieving contextual fear are temporally separated across three days. The current study asked whether neonatal alcohol exposure impairs context learning, consolidation, or retrieval and examined prefrontal and hippocampal molecular signaling as correlates of this impairment. Long-Evans rats that received oral intubation of ethanol (AE; 5.25 g/kg/day, split into two doses) or underwent sham-intubation (SI) from PND4-9 were tested on the CPFE on PD31-33. Extending our previous reports, ethanol abolished both post-shock and retention test freezing in the CPFE. Assays (qPCR) of immediate early gene expression revealed that ethanol disrupted prefrontal but not hippocampal expression of c-Fos, Arc, Egr-1, and Npas4 during context learning. Finally, ethanol-exposed animals were unimpaired in a standard contextual fear conditioning procedure in which learning about the context and acquiring a context-shock association occurs concurrently. These findings implicate impaired prefrontal function in cognitive deficits arising from 3rd-trimester equivalent alcohol exposure in the rat.
Collapse
|
15
|
Hippocampal neural progenitor cells play a distinct role in fear memory retrieval in male and female CIE rats. Neuropharmacology 2018; 143:239-249. [PMID: 30273595 DOI: 10.1016/j.neuropharm.2018.09.045] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Revised: 09/12/2018] [Accepted: 09/27/2018] [Indexed: 12/24/2022]
Abstract
Adult male and female GFAP-TK transgenic rats experienced six weeks of chronic intermittent ethanol vapor inhalation (CIE). During the last week of CIE, a subset of male and female TK rats were fed with Valcyte to ablate neural progenitor cells (NPCs). Seventy-two hours after CIE cessation, all CIE and age-matched ethanol naïve controls experienced auditory trace fear conditioning (TFC). Twenty-four hours later all animals were tested for cue-mediated retrieval in the fear context. Adult male CIE rats showed a significant burst in NPCs paralleled by reduction in fear retrieval compared to naïve controls and Valcyte treated CIE rats. Adult female CIE rats did not show a burst in NPCs and showed similar fear retrieval compared to naïve controls and Valcyte treated CIE rats, indicating that CIE-mediated impairment in fear memory and its regulation by NPCs was sex dependent. Valcyte significantly reduced Ki-67 and NeuroD labeled cells in the dentate gyrus (DG) in both sexes, demonstrating a role for NPCs in reduced fear retrieval in males. Valcyte prevented adaptations in GluN2A receptor expression and synaptoporin density in the DG in males, indicating that NPCs contributed to alterations in plasticity-related proteins and mossy fiber projections that were associated with reduced fear retrieval. These data suggest that DG NPCs born during withdrawal and early abstinence from CIE are aberrant, and could play a role in weakening long-term memory consolidation dependent on the hippocampus.
Collapse
|
16
|
Sharma V, Cohen N, Sood R, Ounallah-Saad H, Gal-Ben-Ari S, Rosenblum K. Trace Fear Conditioning: Procedure for Assessing Complex Hippocampal Function in Mice. Bio Protoc 2018; 8:e2475. [PMID: 34395771 PMCID: PMC8328640 DOI: 10.21769/bioprotoc.2475] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 12/06/2017] [Accepted: 01/08/2018] [Indexed: 10/20/2023] Open
Abstract
The trace fear conditioning protocol is designed to measure hippocampal function in mice. The protocol includes a neutral conditioned stimulus (tone) and an aversive unconditioned stimulus (shock), separated in time by a trace interval. The trace interval between the tone and the shock critically involves the hippocampus and could be used to evaluate hippocampal-dependent learning and memory. In this protocol, we presented mice with five pairings of tone and shock separated by a 20 sec trace interval. Freezing was measured 24 h after conditioning to evaluate contextual memory by placing mice in the conditioned chamber. In addition, 48 h after conditioning, freezing was measured in a dark chamber, which served as a different context. This method enables precise detection of hippocampal-dependent learning and memory following pharmacological and genetic manipulations that impair or enhance hippocampal function.
Collapse
Affiliation(s)
- Vijendra Sharma
- Department of Biochemistry, McGill University, Montréal, Québec, Canada
| | - Noah Cohen
- Department of Biochemistry, McGill University, Montréal, Québec, Canada
| | - Rapita Sood
- Department of Biochemistry, McGill University, Montréal, Québec, Canada
| | - Hadile Ounallah-Saad
- Sagol Department of Neurobiology, University of Haifa, Haifa, Israel
- Center for Gene Manipulation in the Brain, University of Haifa, Haifa, Israel
| | | | - Kobi Rosenblum
- Sagol Department of Neurobiology, University of Haifa, Haifa, Israel
- Center for Gene Manipulation in the Brain, University of Haifa, Haifa, Israel
| |
Collapse
|
17
|
Hales JB, Vincze JL, Reitz NT, Ocampo AC, Leutgeb S, Clark RE. Recent and remote retrograde memory deficit in rats with medial entorhinal cortex lesions. Neurobiol Learn Mem 2018; 155:157-163. [PMID: 30075194 DOI: 10.1016/j.nlm.2018.07.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 07/03/2018] [Accepted: 07/30/2018] [Indexed: 11/19/2022]
Abstract
The hippocampus is critically involved in the acquisition and retrieval of spatial memories. Even though some memories become independent of the hippocampus over time, expression of spatial memories have consistently been found to permanently depend on the hippocampus. Recent studies have focused on the adjacent medial entorhinal cortex (MEC), as it provides major projections to the hippocampus. These studies have shown that lesions of the MEC disrupt spatial processing in the hippocampus and impair spatial memory acquisition on the watermaze task. MEC lesions acquired after learning the watermaze task also disrupt recently acquired spatial memories. However, the effect of MEC lesions on remotely acquired memories is unknown. The current study examined the effect of MEC lesions on recent and remote memory retrieval using three hippocampus-dependent tasks: the watermaze, trace fear conditioning, and novel object recognition. MEC lesions caused impaired retrieval of recently and remotely acquired memory for the watermaze. Rats with MEC lesions also showed impaired fear memory when exposed to the previously conditioned context or the associated tone, and this reduction was seen both when the lesion occurred soon after trace fear condition and when it occurred a month after conditioning. In contrast, MEC lesions did not disrupt novel object recognition. These findings indicate that even with an intact hippocampus, rats with MEC lesions cannot retrieve recent or remote spatial memories. In addition, the involvement of the MEC in memory extends beyond is role in navigation and place memory.
Collapse
Affiliation(s)
- Jena B Hales
- Department of Psychological Sciences, University of San Diego, San Diego, CA 92110, USA.
| | - Jonathan L Vincze
- Department of Psychological Sciences, University of San Diego, San Diego, CA 92110, USA
| | - Nicole T Reitz
- Department of Psychological Sciences, University of San Diego, San Diego, CA 92110, USA
| | - Amber C Ocampo
- Department of Psychology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Stefan Leutgeb
- Neurobiology Section and Center for Neural Circuits and Behavior, Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA; Kavli Institute for Brain and Mind, University of California, San Diego, La Jolla, CA 92093, USA
| | - Robert E Clark
- Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA; Department of Psychiatry, University of California, San Diego, La Jolla, CA 92093, USA.
| |
Collapse
|
18
|
A hippocampus to prefrontal cortex neural pathway inhibits food motivation through glucagon-like peptide-1 signaling. Mol Psychiatry 2018; 23:1555-1565. [PMID: 28461695 PMCID: PMC5668211 DOI: 10.1038/mp.2017.91] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/10/2017] [Accepted: 03/16/2017] [Indexed: 12/18/2022]
Abstract
The hippocampus and the medial prefrontal cortex (mPFC) are traditionally associated with regulating memory and executive function, respectively. The contribution of these brain regions to food intake control, however, is poorly understood. The present study identifies a novel neural pathway through which monosynaptic glutamatergic ventral hippocampal field CA1 (vCA1) to mPFC connectivity inhibits food-motivated behaviors through vCA1 glucagon-like peptide-1 receptor (GLP-1R). Results demonstrate that vCA1-targeted RNA interference-mediated GLP-1R knockdown increases motivated operant responding for palatable food. Chemogenetic disconnection of monosynaptic glutamatergic vCA1 to mPFC projections using designer receptors exclusively activated by designer drugs (DREADDs)-mediated synaptic silencing ablates the food intake and body weight reduction following vCA1 GLP-1R activation. Neuropharmacological experiments further reveal that vCA1 GLP-1R activation reduces food intake and inhibits impulsive operant responding for palatable food via downstream communication to mPFC NMDA receptors. Overall these findings identify a novel neural pathway regulating higher-order cognitive aspects of feeding behavior.
Collapse
|
19
|
Scheggia D, Zamberletti E, Realini N, Mereu M, Contarini G, Ferretti V, Managò F, Margiani G, Brunoro R, Rubino T, De Luca MA, Piomelli D, Parolaro D, Papaleo F. Remote memories are enhanced by COMT activity through dysregulation of the endocannabinoid system in the prefrontal cortex. Mol Psychiatry 2018. [PMID: 28630452 DOI: 10.1038/mp.2017.126] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The prefrontal cortex (PFC) is a crucial hub for the flexible modulation of recent memories (executive functions) as well as for the stable organization of remote memories. Dopamine in the PFC is implicated in both these processes and genetic variants affecting its neurotransmission might control the unique balance between cognitive stability and flexibility present in each individual. Functional genetic variants in the catechol-O-methyltransferase (COMT) gene result in a different catabolism of dopamine in the PFC. However, despite the established role played by COMT genetic variation in executive functions, its impact on remote memory formation and recall is still poorly explored. Here we report that transgenic mice overexpressing the human COMT-Val gene (COMT-Val-tg) present exaggerated remote memories (>50 days) while having unaltered recent memories (<24 h). COMT selectively and reversibly modulated the recall of remote memories as silencing COMT Val overexpression starting from 30 days after the initial aversive conditioning normalized remote memories. COMT genetic overactivity produced a selective overdrive of the endocannabinoid system within the PFC, but not in the striatum and hippocampus, which was associated with enhanced remote memories. Indeed, acute pharmacological blockade of CB1 receptors was sufficient to rescue the altered remote memory recall in COMT-Val-tg mice and increased PFC dopamine levels. These results demonstrate that COMT genetic variations modulate the retrieval of remote memories through the dysregulation of the endocannabinoid system in the PFC.
Collapse
Affiliation(s)
- D Scheggia
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genoa, Italy
| | - E Zamberletti
- Department of Biotechnology and Life Sciences, and Neuroscience Center, University of Insubria, Busto Arsizio, Italy
| | - N Realini
- Drug Discovery and Development, Istituto Italiano di Tecnologia, Genoa, Italy
| | - M Mereu
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genoa, Italy.,Dipartimento di Scienze del Farmaco, Universita' degli Studi di Padova, Largo Meneghetti, Padova, Italy
| | - G Contarini
- Dipartimento di Scienze del Farmaco, Universita' degli Studi di Padova, Largo Meneghetti, Padova, Italy
| | - V Ferretti
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genoa, Italy
| | - F Managò
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genoa, Italy
| | - G Margiani
- Department of Biomedical Sciences, Università di Cagliari, Cagliari, Italy
| | - R Brunoro
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genoa, Italy
| | - T Rubino
- Department of Biotechnology and Life Sciences, and Neuroscience Center, University of Insubria, Busto Arsizio, Italy
| | - M A De Luca
- Department of Biomedical Sciences, Università di Cagliari, Cagliari, Italy
| | - D Piomelli
- Drug Discovery and Development, Istituto Italiano di Tecnologia, Genoa, Italy.,Department of Anatomy and Neurobiology, Pharmacology and Biological Chemistry, University of California, Irvine, Irvine, CA, USA
| | - D Parolaro
- Department of Biotechnology and Life Sciences, and Neuroscience Center, University of Insubria, Busto Arsizio, Italy
| | - F Papaleo
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genoa, Italy
| |
Collapse
|
20
|
Ocampo AC, Squire LR, Clark RE. Hippocampal area CA1 and remote memory in rats. ACTA ACUST UNITED AC 2017; 24:563-568. [PMID: 29038217 PMCID: PMC5647930 DOI: 10.1101/lm.045781.117] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 07/17/2017] [Indexed: 12/01/2022]
Abstract
Hippocampal lesions often produce temporally graded retrograde amnesia (TGRA), whereby recent memory is impaired more than remote memory. This finding has provided support for the process of systems consolidation. However, temporally graded memory impairment has not been observed with the watermaze task, and the findings have been inconsistent with context fear conditioning. One possibility is that large hippocampal lesions indirectly disrupt (by retrograde degeneration) the function of areas that project to the hippocampus that are important for task performance or thought to be important for storing consolidated memories. We developed a discrete lesion targeting area CA1, the sole output of the hippocampus to neocortex, and tested the effects of this lesion on recent and remote memory in the watermaze task, in context fear conditioning, and in trace fear conditioning. In all three tasks, recent and remote memory were similarly impaired after CA1 lesions. We discuss factors that help to illuminate these findings and consider their relevance to systems consolidation.
Collapse
Affiliation(s)
- Amber C Ocampo
- Department of Psychology, University of California, San Diego, La Jolla, California 92093, USA
| | - Larry R Squire
- Veterans Affairs San Diego Healthcare System, San Diego, California 92161, USA.,Departments of Psychiatry, Neurosciences, and Psychology, University of California, San Diego, La Jolla, California 92093, USA
| | - Robert E Clark
- Veterans Affairs San Diego Healthcare System, San Diego, California 92161, USA.,Department of Psychiatry, University of California, San Diego, La Jolla, California 92093, USA
| |
Collapse
|
21
|
Pedraza LK, Sierra RO, Crestani AP, Quillfeldt JA, de Oliveira Alvares L. Sequential learning during contextual fear conditioning guides the rate of systems consolidation: Implications for consolidation of multiple memory traces. Hippocampus 2017; 27:518-528. [DOI: 10.1002/hipo.22708] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Revised: 01/05/2017] [Accepted: 01/12/2017] [Indexed: 11/10/2022]
Affiliation(s)
- Lizeth K. Pedraza
- Laboratório de Neurobiologia da Memória; Biophysics Department, Biosciences Institute, Universidade Federal do Rio Grande do Sul; Porto Alegre RS, Brazil
- Institute of Health Sciences, Graduate Program in Neuroscience; Universidade Federal do Rio Grande do Sul; Porto Alegre RS, Brazil
| | - Rodrigo O. Sierra
- Institute of Health Sciences, Graduate Program in Neuroscience; Universidade Federal do Rio Grande do Sul; Porto Alegre RS, Brazil
- Laboratório de Psicobiologia e Neurocomputação, Biophysics Department; Biosciences Institute, Universidade Federal do Rio Grande do Sul; Porto Alegre Brazil
| | - Ana P. Crestani
- Institute of Health Sciences, Graduate Program in Neuroscience; Universidade Federal do Rio Grande do Sul; Porto Alegre RS, Brazil
- Laboratório de Psicobiologia e Neurocomputação, Biophysics Department; Biosciences Institute, Universidade Federal do Rio Grande do Sul; Porto Alegre Brazil
| | - Jorge A. Quillfeldt
- Institute of Health Sciences, Graduate Program in Neuroscience; Universidade Federal do Rio Grande do Sul; Porto Alegre RS, Brazil
- Laboratório de Psicobiologia e Neurocomputação, Biophysics Department; Biosciences Institute, Universidade Federal do Rio Grande do Sul; Porto Alegre Brazil
| | - Lucas de Oliveira Alvares
- Laboratório de Neurobiologia da Memória; Biophysics Department, Biosciences Institute, Universidade Federal do Rio Grande do Sul; Porto Alegre RS, Brazil
- Institute of Health Sciences, Graduate Program in Neuroscience; Universidade Federal do Rio Grande do Sul; Porto Alegre RS, Brazil
| |
Collapse
|
22
|
Fear memory in a neurodevelopmental model of schizophrenia based on the postnatal blockade of NMDA receptors. Pharmacol Rep 2017; 69:71-76. [DOI: 10.1016/j.pharep.2016.10.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 10/14/2016] [Accepted: 10/14/2016] [Indexed: 01/12/2023]
|
23
|
Hunt PS, Burk JA, Barnet RC. Adolescent transitions in reflexive and non-reflexive behavior: Review of fear conditioning and impulse control in rodent models. Neurosci Biobehav Rev 2016; 70:33-45. [PMID: 27339692 PMCID: PMC5074887 DOI: 10.1016/j.neubiorev.2016.06.026] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 06/03/2016] [Accepted: 06/18/2016] [Indexed: 01/11/2023]
Abstract
Adolescence is a time of critical brain changes that pave the way for adult learning processes. However, the extent to which learning in adolescence is best characterized as a transitional linear progression from childhood to adulthood, or represents a period that differs from earlier and later developmental stages, remains unclear. Here we examine behavioral literature on associative fear conditioning and complex choice behavior with rodent models. Many aspects of fear conditioning are intact by adolescence and do not differ from adult patterns. Sufficient evidence, however, suggests that adolescent learning cannot be characterized simply as an immature precursor to adulthood. Across different paradigms assessing choice behavior, literature suggests that adolescent animals typically display more impulsive patterns of responding compared to adults. The extent to which the development of basic conditioning processes serves as a scaffold for later adult decision making is an additional research area that is important for theory, but also has widespread applications for numerous psychological conditions.
Collapse
|
24
|
Choi KY, Kim YK. Plasticity-augmented psychotherapy for refractory depressive and anxiety disorders. Prog Neuropsychopharmacol Biol Psychiatry 2016; 70:134-47. [PMID: 27072378 DOI: 10.1016/j.pnpbp.2016.04.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 04/07/2016] [Accepted: 04/08/2016] [Indexed: 12/28/2022]
Abstract
Psychotherapy and pharmacotherapy have been the mainstays of treatment for depression and anxiety disorders during the last century. However, treatment response has not improved in the last few decades, with only half of all patients responding satisfactorily to typical antidepressants. To fulfill the needs of the remaining patients, new treatments with better efficacy are in demand. The addition of psychotherapy to antidepressant treatment has been shown to be superior to pharmacotherapy alone. However, the time costs of psychotherapy limit its use for clinicians and patients. Advancements in neuroscience have contributed to an improved understanding of the pathogenesis of depressive and anxiety disorders. In particular, recent advances in the field of fear conditioning have provided valuable insight into the treatment of refractory depressive and anxiety disorders. In this review, we studied the reconsolidation-updating paradigm and the concept of epigenetic modification, which has been shown to permanently attenuate remote fear memory. This has implications for drug-augmented, e.g. antidepressant and valproic acid, psychotherapy. Future research on more sophisticated psychotherapy techniques will increase the desirability of this treatment modality for both clinicians and patients.
Collapse
Affiliation(s)
- Kwang-Yeon Choi
- Department of Psychiatry, Korea University College of Medicine, Seoul, Republic of Korea
| | - Yong-Ku Kim
- Department of Psychiatry, Korea University College of Medicine, Seoul, Republic of Korea.
| |
Collapse
|
25
|
Connor DA, Gould TJ. The role of working memory and declarative memory in trace conditioning. Neurobiol Learn Mem 2016; 134 Pt B:193-209. [PMID: 27422017 PMCID: PMC5755400 DOI: 10.1016/j.nlm.2016.07.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 07/07/2016] [Accepted: 07/11/2016] [Indexed: 01/18/2023]
Abstract
Translational assays of cognition that are similarly implemented in both lower and higher-order species, such as rodents and primates, provide a means to reconcile preclinical modeling of psychiatric neuropathology and clinical research. To this end, Pavlovian conditioning has provided a useful tool for investigating cognitive processes in both lab animal models and humans. This review focuses on trace conditioning, a form of Pavlovian conditioning typified by the insertion of a temporal gap (i.e., trace interval) between presentations of a conditioned stimulus (CS) and an unconditioned stimulus (US). This review aims to discuss pre-clinical and clinical work investigating the mnemonic processes recruited for trace conditioning. Much work suggests that trace conditioning involves unique neurocognitive mechanisms to facilitate formation of trace memories in contrast to standard Pavlovian conditioning. For example, the hippocampus and prefrontal cortex (PFC) appear to play critical roles in trace conditioning. Moreover, cognitive mechanistic accounts in human studies suggest that working memory and declarative memory processes are engaged to facilitate formation of trace memories. The aim of this review is to integrate cognitive and neurobiological accounts of trace conditioning from preclinical and clinical studies to examine involvement of working and declarative memory.
Collapse
Affiliation(s)
- David A Connor
- Department of Psychology, Neuroscience Program, Temple University, Philadelphia, PA 19122, United States
| | - Thomas J Gould
- Department of Psychology, Neuroscience Program, Temple University, Philadelphia, PA 19122, United States.
| |
Collapse
|
26
|
Do Monte FH, Quirk GJ, Li B, Penzo MA. Retrieving fear memories, as time goes by…. Mol Psychiatry 2016; 21:1027-36. [PMID: 27217148 PMCID: PMC4956525 DOI: 10.1038/mp.2016.78] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 03/22/2016] [Accepted: 04/05/2016] [Indexed: 12/12/2022]
Abstract
Research in fear conditioning has provided a comprehensive picture of the neuronal circuit underlying the formation of fear memories. In contrast, our understanding of the retrieval of fear memories is much more limited. This disparity may stem from the fact that fear memories are not rigid, but reorganize over time. To bring some clarity and raise awareness about the time-dependent dynamics of retrieval circuits, we review current evidence on the neuronal circuitry participating in fear memory retrieval at both early and late time points following auditory fear conditioning. We focus on the temporal recruitment of the paraventricular nucleus of the thalamus (PVT) for the retrieval and maintenance of fear memories. Finally, we speculate as to why retrieval circuits change with time, and consider the functional strategy of recruiting structures not previously considered as part of the retrieval circuit.
Collapse
Affiliation(s)
- Fabricio H. Do Monte
- Departments of Psychiatry and Anatomy & Neurobiology, University of Puerto Rico School of Medicine, PO Box 365067, San Juan 00936, Puerto Rico
| | - Gregory J. Quirk
- Departments of Psychiatry and Anatomy & Neurobiology, University of Puerto Rico School of Medicine, PO Box 365067, San Juan 00936, Puerto Rico
| | - Bo Li
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724
| | - Mario A. Penzo
- National Institute of Mental Health, 35 Convent Drive, Bldg. 35A Room 2E621, Bethesda, MD 20850
| |
Collapse
|
27
|
Knox D. The role of basal forebrain cholinergic neurons in fear and extinction memory. Neurobiol Learn Mem 2016; 133:39-52. [PMID: 27264248 DOI: 10.1016/j.nlm.2016.06.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 05/26/2016] [Accepted: 06/02/2016] [Indexed: 12/30/2022]
Abstract
Cholinergic input to the neocortex, dorsal hippocampus (dHipp), and basolateral amygdala (BLA) is critical for neural function and synaptic plasticity in these brain regions. Synaptic plasticity in the neocortex, dHipp, ventral Hipp (vHipp), and BLA has also been implicated in fear and extinction memory. This finding raises the possibility that basal forebrain (BF) cholinergic neurons, the predominant source of acetylcholine in these brain regions, have an important role in mediating fear and extinction memory. While empirical studies support this hypothesis, there are interesting inconsistencies among these studies that raise questions about how best to define the role of BF cholinergic neurons in fear and extinction memory. Nucleus basalis magnocellularis (NBM) cholinergic neurons that project to the BLA are critical for fear memory and contextual fear extinction memory. NBM cholinergic neurons that project to the neocortex are critical for cued and contextual fear conditioned suppression, but are not critical for fear memory in other behavioral paradigms and in the inhibitory avoidance paradigm may even inhibit contextual fear memory formation. Medial septum and diagonal band of Broca cholinergic neurons are critical for contextual fear memory and acquisition of cued fear extinction. Thus, even though the results of previous studies suggest BF cholinergic neurons modulate fear and extinction memory, inconsistent findings among these studies necessitates more research to better define the neural circuits and molecular processes through which BF cholinergic neurons modulate fear and extinction memory. Furthermore, studies determining if BF cholinergic neurons can be manipulated in such a manner so as to treat excessive fear in anxiety disorders are needed.
Collapse
Affiliation(s)
- Dayan Knox
- Department of Psychological and Brain Sciences, Behavioral Neuroscience Program, University of Delaware, Newark, DE, United States.
| |
Collapse
|
28
|
Antidepressant-like effect of cannabidiol injection into the ventral medial prefrontal cortex—Possible involvement of 5-HT1A and CB1 receptors. Behav Brain Res 2016; 303:218-27. [DOI: 10.1016/j.bbr.2016.01.033] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 01/12/2016] [Accepted: 01/15/2016] [Indexed: 01/24/2023]
|
29
|
Haubrich J, Cassini LF, Diehl F, Santana F, Fürstenau de Oliveira L, de Oliveira Alvares L, Quillfeldt JA. Novel learning accelerates systems consolidation of a contextual fear memory. Hippocampus 2016; 26:924-32. [DOI: 10.1002/hipo.22575] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/04/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Josue Haubrich
- Departamento de Biofísica, Laboratório de Psicobiologia e Neurocomputação, Instituto de Biociências; Universidade Federal do Rio Grande do Sul-Porto Alegre; RS Brazil
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas Da Saúde; Universidade Federal do Rio Grande do Sul-Porto Alegre; RS Brazil
| | - Lindsey Freitas Cassini
- Departamento de Biofísica, Laboratório de Psicobiologia e Neurocomputação, Instituto de Biociências; Universidade Federal do Rio Grande do Sul-Porto Alegre; RS Brazil
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas Da Saúde; Universidade Federal do Rio Grande do Sul-Porto Alegre; RS Brazil
| | - Felipe Diehl
- Departamento de Biofísica, Laboratório de Psicobiologia e Neurocomputação, Instituto de Biociências; Universidade Federal do Rio Grande do Sul-Porto Alegre; RS Brazil
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas Da Saúde; Universidade Federal do Rio Grande do Sul-Porto Alegre; RS Brazil
| | - Fabiana Santana
- Departamento de Biofísica, Laboratório de Psicobiologia e Neurocomputação, Instituto de Biociências; Universidade Federal do Rio Grande do Sul-Porto Alegre; RS Brazil
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas Da Saúde; Universidade Federal do Rio Grande do Sul-Porto Alegre; RS Brazil
| | - Lucas Fürstenau de Oliveira
- Departamento de Biofísica, Laboratório de Psicobiologia e Neurocomputação, Instituto de Biociências; Universidade Federal do Rio Grande do Sul-Porto Alegre; RS Brazil
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas Da Saúde; Universidade Federal do Rio Grande do Sul-Porto Alegre; RS Brazil
| | - Lucas de Oliveira Alvares
- Departamento de Biofísica, Laboratório de Psicobiologia e Neurocomputação, Instituto de Biociências; Universidade Federal do Rio Grande do Sul-Porto Alegre; RS Brazil
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas Da Saúde; Universidade Federal do Rio Grande do Sul-Porto Alegre; RS Brazil
- Departamento de Biofísica, Laboratório de Neurobiologia da Memória, Instituto de Biociências; Universidade Federal Do Rio Grande do Sul-Porto Alegre; RS Brazil
| | - Jorge Alberto Quillfeldt
- Departamento de Biofísica, Laboratório de Psicobiologia e Neurocomputação, Instituto de Biociências; Universidade Federal do Rio Grande do Sul-Porto Alegre; RS Brazil
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas Da Saúde; Universidade Federal do Rio Grande do Sul-Porto Alegre; RS Brazil
| |
Collapse
|
30
|
Osborne DM, Fitzgerald DP, O'Leary KE, Anderson BM, Lee CC, Tessier PM, McNay EC. Intrahippocampal administration of a domain antibody that binds aggregated amyloid-β reverses cognitive deficits produced by diet-induced obesity. Biochim Biophys Acta Gen Subj 2016; 1860:1291-8. [PMID: 26970498 DOI: 10.1016/j.bbagen.2016.03.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 02/20/2016] [Accepted: 03/06/2016] [Indexed: 12/29/2022]
Abstract
BACKGROUND The prevalence of high fat diets (HFD), diet-induced obesity (DIO) and Type 2 diabetes continues to increase, associated with cognitive impairment in both humans and rodent models. Mechanisms transducing these impairments remain largely unknown: one possibility is that a common mechanism may be involved in the cognitive impairment seen in obese and/or diabetic states and in dementia, specifically Alzheimer's disease (AD). DIO is well established as a risk factor for development of AD. Oligomeric amyloid-β (Aβ) is neurotoxic, and we showed that intrahippocampal oligomeric Aβ produces cognitive and metabolic dysfunction similar to that seen in DIO or diabetes. Moreover, animal models of DIO show elevated brain Aβ, a hallmark of AD, suggesting that this may be one source of cognitive impairment in both conditions. METHODS Intrahippocampal administration of a novel anti-Aβ domain antibody for aggregated Aβ, or a control domain antibody, to control or HFD-induced DIO rats. Spatial learning measured in a conditioned contextual fear (CCF) task after domain antibody treatment; postmortem, hippocampal NMDAR and AMPAR were measured. RESULTS DIO caused impairment in CCF, and this impairment was eliminated by intrahippocampal administration of the active domain antibody. Measurement of hippocampal proteins suggests that DIO causes dysregulation of hippocampal AMPA receptors, which is also reversed by acute domain antibody administration. CONCLUSIONS Our findings support the concept that oligomeric Aβ within the hippocampus of DIO animals may not only be a risk factor for development of AD but may also cause cognitive impairment before the development of dementia. GENERAL SIGNIFICANCE AND INTEREST Our work integrates the engineering of domain antibodies with conformational- and sequence-specificity for oligomeric amyloid beta with a clinically relevant model of diet-induced obesity in order to demonstrate not only the pervasive effects of obesity on several aspects of brain biochemistry and behavior, but also the bioengineering of a successful treatment against the long-term detrimental effects of a pre-diabetic state on the brain. We show for the first time that cognitive impairment linked to obesity and/or insulin resistance may be due to early accumulation of oligomeric beta-amyloid in the brain, and hence may represent a pre-Alzheimer's state.
Collapse
Affiliation(s)
- Danielle M Osborne
- Behavioral Neuroscience, University at Albany, Albany, NY, United States; Center for Neuroscience Research, University at Albany, Albany, NY, United States
| | - Dennis P Fitzgerald
- Hofstra North Shore-Long Island School of Medicine, Hofstra University, Hempstead, NY, United States
| | - Kelsey E O'Leary
- University of Virginia School of Medicine, Charlottesville, VA, United States
| | - Brian M Anderson
- Center for Neuropharmacology and Neuroscience, Albany Medical College, Albany, NY, United States
| | - Christine C Lee
- Center for Biotechnology and Interdisciplinary Studies, Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, United States
| | - Peter M Tessier
- Center for Biotechnology and Interdisciplinary Studies, Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, United States
| | - Ewan C McNay
- Behavioral Neuroscience, University at Albany, Albany, NY, United States; Center for Neuroscience Research, University at Albany, Albany, NY, United States; Biological Sciences, University at Albany, Albany, NY, United States.
| |
Collapse
|
31
|
Koh MT, Shao Y, Sherwood A, Smith DR. Impaired hippocampal-dependent memory and reduced parvalbumin-positive interneurons in a ketamine mouse model of schizophrenia. Schizophr Res 2016; 171:187-94. [PMID: 26811256 PMCID: PMC4762714 DOI: 10.1016/j.schres.2016.01.023] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 01/09/2016] [Accepted: 01/11/2016] [Indexed: 01/23/2023]
Abstract
The hippocampus of patients with schizophrenia displays aberrant excess neuronal activity which affects cognitive function. Animal models of the illness have recapitulated the overactivity in the hippocampus, with a corresponding regionally localized reduction of inhibitory interneurons, consistent with that observed in patients. To better understand whether cognitive function is similarly affected in these models of hippocampal overactivity, we tested a ketamine mouse model of schizophrenia for cognitive performance in hippocampal- and medial prefrontal cortex (mPFC)-dependent tasks. We found that adult mice exposed to ketamine during adolescence were impaired on a trace fear conditioning protocol that relies on the integrity of the hippocampus. Conversely, the performance of the mice was normal on a delayed response task that is sensitive to mPFC damage. We confirmed that ketamine-exposed mice had reduced parvalbumin-positive interneurons in the hippocampus, specifically in the CA1, but not in the mPFC in keeping with the behavioral findings. These results strengthened the utility of the ketamine model for preclinical investigations of hippocampal overactivity in schizophrenia.
Collapse
Affiliation(s)
- Ming Teng Koh
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD 21218, USA.
| | | | | | | |
Collapse
|
32
|
Pierson JL, Pullins SE, Quinn JJ. Dorsal hippocampus infusions of CNQX into the dentate gyrus disrupt expression of trace fear conditioning. Hippocampus 2015; 25:779-85. [DOI: 10.1002/hipo.22413] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/29/2014] [Indexed: 01/08/2023]
Affiliation(s)
- Jamie L. Pierson
- Department of Psychology and Center for Neuroscience & Behavior; Miami University; Oxford Ohio
| | - Shane E. Pullins
- Department of Psychology and Center for Neuroscience & Behavior; Miami University; Oxford Ohio
| | - Jennifer J. Quinn
- Department of Psychology and Center for Neuroscience & Behavior; Miami University; Oxford Ohio
| |
Collapse
|
33
|
Schreiber WB, Asok A, Jablonski SA, Rosen JB, Stanton ME. Egr-1 mRNA expression patterns in the prefrontal cortex, hippocampus, and amygdala during variants of contextual fear conditioning in adolescent rats. Brain Res 2014; 1576:63-72. [PMID: 24976583 PMCID: PMC4138218 DOI: 10.1016/j.brainres.2014.06.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 06/03/2014] [Accepted: 06/05/2014] [Indexed: 10/25/2022]
Abstract
We report activation of the immediate-early gene Egr-1 in the lateral amygdala (LA), hippocampus (CA1), and medial prefrontal cortex (mPFC) 30-min following the training phase in the context pre-exposure facilitation effect (CPFE) and standard context fear conditioning (180 s context exposure→shock). On day one of the CPFE paradigm, postnatal day (PD) 31 rats (±1) were pre-exposed to Context A (Pre) or Context B (Alt-Pre) for 5 min followed by five additional 1-min exposures. A day later, Pre and Alt-Pre rats received a 2-s, 1.5 mA footshock immediately upon placement in Context A. Animals included in in situ hybridization were then sacrificed 30 (±3) min later. On day three, the behaviorally-tested Pre rats showed significantly more fear-conditioned freezing in Context A than Alt-Pre rats. Standard context fear conditioning groups showed much greater freezing than the Pre group, as well as no shock and immediate-shock controls. Thirty minutes after immediate shock training, Pre rats showed increased Egr-1 mRNA in the prelimbic mPFC relative to Alt-Pre rats. Standard context conditioning selectively increased Egr-1 in CA1. In the LA and mPFC, Egr-1 increased to a similar extent in no shock, immediate shock, and standard context conditioning relative to homecage controls. The present study demonstrates that Egr-1 mRNA expression has a complex relationship to fear learning in different brain regions and variants of context conditioning.
Collapse
Affiliation(s)
- W B Schreiber
- Department of Psychological & Brain Sciences, University of Delaware, Newark, DE 19716, USA
| | - A Asok
- Department of Psychological & Brain Sciences, University of Delaware, Newark, DE 19716, USA
| | - S A Jablonski
- Department of Psychological & Brain Sciences, University of Delaware, Newark, DE 19716, USA
| | - J B Rosen
- Department of Psychological & Brain Sciences, University of Delaware, Newark, DE 19716, USA
| | - M E Stanton
- Department of Psychological & Brain Sciences, University of Delaware, Newark, DE 19716, USA.
| |
Collapse
|
34
|
Raybuck JD, Lattal KM. Differential effects of dorsal hippocampal inactivation on expression of recent and remote drug and fear memory. Neurosci Lett 2014; 569:1-5. [PMID: 24686177 DOI: 10.1016/j.neulet.2014.02.063] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Revised: 02/21/2014] [Accepted: 02/24/2014] [Indexed: 01/08/2023]
Abstract
Drugs of abuse generate strong drug-context associations, which can evoke powerful drug cravings that are linked to reinstatement in animal models and to relapse in humans. Work in learning and memory has demonstrated that contextual memories become more distributed over time, shifting from dependence on the hippocampus for retrieval to dependence on cortical structures. Implications for such changes in the structure of memory retrieval to addiction are unknown. Thus, to determine if the passage of time alters the substrates of conditioned place preference (CPP) memory retrieval, we investigated the effects of inactivation of the dorsal hippocampus (DH) with the GABA-A receptor agonist muscimol on expression of recent or remote CPP. We compared these effects with the same manipulation on expression of contextual fear conditioning. DH inactivation produced similar deficits in expression of both recent and remote CPP, but blocked expression of recent but not remote contextual fear memory. We describe the implications of these findings for mechanisms underlying long-term storage of contextual information.
Collapse
Affiliation(s)
- J D Raybuck
- Department of Behavioral Neuroscience, Oregon Health & Science University, 3181 SW Sam Jackson Park Road L470, Portland, OR 97239-3098, USA.
| | - K M Lattal
- Department of Behavioral Neuroscience, Oregon Health & Science University, 3181 SW Sam Jackson Park Road L470, Portland, OR 97239-3098, USA.
| |
Collapse
|
35
|
Luyten L, Schroyens N, Hermans D, Beckers T. Parameter optimization for automated behavior assessment: plug-and-play or trial-and-error? Front Behav Neurosci 2014; 8:28. [PMID: 24550803 PMCID: PMC3912455 DOI: 10.3389/fnbeh.2014.00028] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 01/20/2014] [Indexed: 11/13/2022] Open
Abstract
Behavioral neuroscience is relying more and more on automated behavior assessment, which is often more time-efficient and objective than manual scoring by a human observer. However, parameter adjustment and calibration are a trial-and-error process that requires careful fine-tuning in order to obtain reliable software scores in each context configuration. In this paper, we will pinpoint some caveats regarding the choice of parameters, and give an overview of our own and other researchers' experience with widely used behavioral assessment software. We conclude that, although each researcher should weigh the pros and cons of relying on software vs. manual scoring, we should be aware of possible divergence between both scores, which might be especially relevant when dealing with subtle behavioral effects, like for example in generalization or genetic research.
Collapse
Affiliation(s)
- Laura Luyten
- Psychology of Learning and Experimental Psychopathology, Faculty of Psychology and Educational Sciences, KU Leuven Leuven, Belgium
| | - Natalie Schroyens
- Experimental Neurosurgery and Neuroanatomy, Department of Neurosciences, KU Leuven Leuven, Belgium
| | - Dirk Hermans
- Psychology of Learning and Experimental Psychopathology, Faculty of Psychology and Educational Sciences, KU Leuven Leuven, Belgium
| | - Tom Beckers
- Psychology of Learning and Experimental Psychopathology, Faculty of Psychology and Educational Sciences, KU Leuven Leuven, Belgium
| |
Collapse
|
36
|
Raybuck JD, Lattal KM. Bridging the interval: theory and neurobiology of trace conditioning. Behav Processes 2014; 101:103-11. [PMID: 24036411 PMCID: PMC3943893 DOI: 10.1016/j.beproc.2013.08.016] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 07/25/2013] [Accepted: 08/09/2013] [Indexed: 12/26/2022]
Abstract
An early finding in the behavioral analysis of learning was that conditioned responding weakens as the conditioned stimulus (CS) and unconditioned stimulus (US) are separated in time. This "trace" conditioning effect has been the focus of years of research in associative learning. Theoretical accounts of trace conditioning have focused on mechanisms that allow associative learning to occur across long intervals between the CS and US. These accounts have emphasized degraded contingency effects, timing mechanisms, and inhibitory learning. More recently, study of the neurobiology of trace conditioning has shown that even a short interval between the CS and US alters the circuitry recruited for learning. Here, we review some of the theoretical and neurobiological mechanisms underlying trace conditioning with an emphasis on recent studies of trace fear conditioning. Findings across many studies have implications not just for how we think about time and conditioning, but also for how we conceptualize fear conditioning in general, suggesting that circuitry beyond the usual suspects needs to be incorporated into current thinking about fear, learning, and anxiety.
Collapse
Affiliation(s)
- Jonathan D Raybuck
- Department of Behavioral Neuroscience, Oregon Health & Science University, United States.
| | - K Matthew Lattal
- Department of Behavioral Neuroscience, Oregon Health & Science University, United States.
| |
Collapse
|
37
|
Federighi G, Traina G, Macchi M, Ciampini C, Bernardi R, Baldi E, Bucherelli C, Brunelli M, Scuri R. Modulation of gene expression in contextual fear conditioning in the rat. PLoS One 2013; 8:e80037. [PMID: 24278235 PMCID: PMC3837011 DOI: 10.1371/journal.pone.0080037] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 09/27/2013] [Indexed: 01/30/2023] Open
Abstract
In contextual fear conditioning (CFC) a single training leads to long-term memory of context-aversive electrical foot-shocks association. Mid-temporal regions of the brain of trained and naive rats were obtained 2 days after conditioning and screened by two-directional suppression subtractive hybridization. A pool of differentially expressed genes was identified and some of them were randomly selected and confirmed with qRT-PCR assay. These transcripts showed high homology for rat gene sequences coding for proteins involved in different cellular processes. The expression of the selected transcripts was also tested in rats which had freely explored the experimental apparatus (exploration) and in rats to which the same number of aversive shocks had been administered in the same apparatus, but temporally compressed so as to make the association between painful stimuli and the apparatus difficult (shock-only). Some genes resulted differentially expressed only in the rats subjected to CFC, others only in exploration or shock-only rats, whereas the gene coding for translocase of outer mitochondrial membrane 20 protein and nardilysin were differentially expressed in both CFC and exploration rats. For example, the expression of stathmin 1 whose transcripts resulted up regulated was also tested to evaluate the transduction and protein localization after conditioning.
Collapse
Affiliation(s)
- Giuseppe Federighi
- Dipartimento di Ricerca Traslazionale e Delle Nuove Tecnologie in Medicina e Chirurgia, Unità di Fisiologia, Università di Pisa, Pisa, Italy
| | - Giovanna Traina
- Dipartimento di Scienze Economico-Estimative e degli Alimenti, Sezione di Chimica Bromatologica, Biochimica, Fisiologia e Nutrizione, Università degli Studi di Perugia, Perugia, Italy
| | - Monica Macchi
- Dipartimento di Biologia, Università di Pisa, Pisa, Italy
| | - Cristina Ciampini
- Dipartimento di Ricerca Traslazionale e Delle Nuove Tecnologie in Medicina e Chirurgia, Unità di Fisiologia, Università di Pisa, Pisa, Italy
| | - Rodolfo Bernardi
- Dipartimento di Scienze Agrarie, Genetica Alimentari e Agro-Ambientali, Università di Pisa, Pisa, Italy
| | - Elisabetta Baldi
- Dipartimento di Scienze Fisiologiche, Università di Firenze, Firenze, Italy
| | - Corrado Bucherelli
- Dipartimento di Scienze Fisiologiche, Università di Firenze, Firenze, Italy
| | | | - Rossana Scuri
- Dipartimento di Ricerca Traslazionale e Delle Nuove Tecnologie in Medicina e Chirurgia, Unità di Fisiologia, Università di Pisa, Pisa, Italy
| |
Collapse
|
38
|
Remote context fear conditioning remains hippocampus-dependent irrespective of training protocol, training-surgery interval, lesion size, and lesion method. Neurobiol Learn Mem 2013; 106:300-8. [PMID: 23994542 DOI: 10.1016/j.nlm.2013.08.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 08/16/2013] [Accepted: 08/20/2013] [Indexed: 11/20/2022]
Abstract
Systems consolidation involves the reorganization of brain circuits that support long-term memory. It is a prolonged process that can take days, weeks, or longer. An animal model of systems consolidation was established in the early 1990s and provided compelling support for the initial observations in humans, that hippocampal damage disproportionally impairs recent memory compared to remote memory. Context fear conditioning was the most frequently and successfully used task to study systems consolidation and demonstrate temporally graded retrograde amnesia. However, recent studies have failed to support these early findings of temporal gradients and instead reported that both recent and remote memories are equally impaired. Thus, the status of context fear conditioning as method to study the process of systems consolidation is at present uncertain. Accordingly, we evaluated classically conditioned fear memory in large groups of rats with hippocampal damage by manipulating several procedural variables including the training protocol, the training-surgery interval, the extent of hippocampal damage, and the method of damaging the hippocampus. The results indicate that hippocampal damage profoundly impairs context fear conditioning. These findings are unambiguous and independent of any particular procedural manipulation we evaluated. We suggest that the preponderance of currently available evidence indicates that context fear memory remains hippocampus-dependent indefinitely.
Collapse
|