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Panzer E, Guimares-Olmo I, Pereira de Vasconcelos A, Stéphan A, Cassel JC. In relentless pursuit of the white whale: A role for the ventral midline thalamus in behavioral flexibility and adaption? Neurosci Biobehav Rev 2024; 163:105762. [PMID: 38857666 DOI: 10.1016/j.neubiorev.2024.105762] [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: 04/25/2024] [Revised: 05/27/2024] [Accepted: 06/04/2024] [Indexed: 06/12/2024]
Abstract
The reuniens (Re) nucleus is located in the ventral midline thalamus. It has fostered increasing interest, not only for its participation in a variety of cognitive functions (e.g., spatial working memory, systemic consolidation, reconsolidation, extinction of fear or generalization), but also for its neuroanatomical positioning as a bidirectional relay between the prefrontal cortex (PFC) and the hippocampus (HIP). In this review we compile and discuss recent studies having tackled a possible implication of the Re nucleus in behavioral flexibility, a major PFC-dependent executive function controlling goal-directed behaviors. Experiments considered explored a possible role for the Re nucleus in perseveration, reversal learning, fear extinction, and set-shifting. They point to a contribution of this nucleus to behavioral flexibility, mainly by its connections with the PFC, but possibly also by those with the hippocampus, and even with the amygdala, at least for fear-related behavior. As such, the Re nucleus could be a crucial crossroad supporting a PFC-orchestrated ability to cope with new, potentially unpredictable environmental contingencies, and thus behavioral flexibility and adaption.
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Affiliation(s)
- Elodie Panzer
- Laboratoire de Neurosciences Cognitives et Adaptatives, Université de Strasbourg, Strasbourg F-67000, France; LNCA, UMR 7364 - CNRS, Strasbourg F-67000, France
| | - Isabella Guimares-Olmo
- Laboratoire de Neurosciences Cognitives et Adaptatives, Université de Strasbourg, Strasbourg F-67000, France; LNCA, UMR 7364 - CNRS, Strasbourg F-67000, France
| | - Anne Pereira de Vasconcelos
- Laboratoire de Neurosciences Cognitives et Adaptatives, Université de Strasbourg, Strasbourg F-67000, France; LNCA, UMR 7364 - CNRS, Strasbourg F-67000, France
| | - Aline Stéphan
- Laboratoire de Neurosciences Cognitives et Adaptatives, Université de Strasbourg, Strasbourg F-67000, France; LNCA, UMR 7364 - CNRS, Strasbourg F-67000, France
| | - Jean-Christophe Cassel
- Laboratoire de Neurosciences Cognitives et Adaptatives, Université de Strasbourg, Strasbourg F-67000, France; LNCA, UMR 7364 - CNRS, Strasbourg F-67000, France.
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Rojas AKP, Linley SB, Vertes RP. Chemogenetic inactivation of the nucleus reuniens and its projections to the orbital cortex produce deficits on discrete measures of behavioral flexibility in the attentional set-shifting task. Behav Brain Res 2024; 470:115066. [PMID: 38801950 DOI: 10.1016/j.bbr.2024.115066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 05/09/2024] [Accepted: 05/21/2024] [Indexed: 05/29/2024]
Abstract
The nucleus reuniens (RE) of the ventral midline thalamus is a critical node in the communication between the orbitomedial prefrontal cortex (OFC) and the hippocampus (HF). While RE has been shown to directly participate in memory-associated functions through its connections with the medial prefrontal cortex and HF, less is known regarding the role of RE in executive functioning. Here, we examined the involvement of RE and its projections to the orbital cortex (ORB) in attention and behavioral flexibility in male rats using the attentional set shifting task (AST). Rats expressing the hM4Di DREADD receptor in RE were implanted with indwelling cannulas in either RE or the ventromedial ORB to pharmacologically inhibit RE or its projections to the ORB with intracranial infusions of clozapine-N-oxide hydrochloride (CNO). Chemogenetic-induced suppression of RE resulted in impairments in reversal learning and set-shifting. This supports a vital role for RE in behavioral flexibility - or the ability to adapt behavior to changing reward or rule contingencies. Interestingly, CNO suppression of RE projections to the ventromedial ORB produced impairments in rule abstraction - or dissociable effects elicited with direct RE suppression. In summary, the present findings indicate that RE, mediated in part by actions on the ORB, serves a critical role in the flexible use of rules to drive goal directed behavior. The cognitive deficits of various neurological disorders with impaired communication between the HF and OFC, may be partly attributed to alterations of RE -- as an established intermediary between these cortical structures.
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Affiliation(s)
- Amanda K P Rojas
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL 33431, USA
| | - Stephanie B Linley
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL 33431, USA; Department of Psychology, Florida Atlantic University, Boca Raton, FL 33431, USA
| | - Robert P Vertes
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL 33431, USA; Department of Psychology, Florida Atlantic University, Boca Raton, FL 33431, USA.
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Gober IG, Russell AL, Shick TJ, Vagni VA, Carlson JC, Kochanek PM, Wagner AK. Exploratory assessment of the effect of systemic administration of soluble glycoprotein 130 on cognitive performance and chemokine levels in a mouse model of experimental traumatic brain injury. J Neuroinflammation 2024; 21:149. [PMID: 38840141 PMCID: PMC11155101 DOI: 10.1186/s12974-024-03129-0] [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: 02/28/2024] [Accepted: 05/12/2024] [Indexed: 06/07/2024] Open
Abstract
Uncontrolled neuroinflammation mediates traumatic brain injury (TBI) pathology and impairs recovery. Interleukin-6 (IL-6), a pleiotropic inflammatory regulator, is associated with poor clinical TBI outcomes. IL-6 operates via classical-signaling through membrane-bound IL-6 receptor (IL-6R) and trans-signaling through soluble IL-6 receptor (s)IL-6R. IL-6 trans-signaling specifically contributes to neuropathology, making it a potential precision therapeutic TBI target. Soluble glycoprotein 130 (sgp130) prevents IL-6 trans-signaling, sparing classical signaling, thus is a possible treatment. Mice received either controlled cortical impact (CCI) (6.0 ± 0.2 m/s; 2 mm; 50-60ms) or sham procedures. Vehicle (VEH) or sgp130-Fc was subcutaneously administered to sham (VEH or 1 µg) and CCI (VEH, 0.25 µg or 1 µg) mice on days 1, 4, 7, 10 and 13 post-surgery to assess effects on cognition [Morris Water Maze (MWM)] and ipsilateral hemisphere IL-6 related biomarkers (day 21 post-surgery). CCI + sgp130-Fc groups (0.25 µg and 1 µg) were combined for analysis given similar behavior/biomarker outcomes. CCI + VEH mice had longer latencies and path lengths to the platform and increased peripheral zone time versus Sham + VEH and Sham + sgp130-Fc mice, suggesting injury-induced impairments in learning and anxiety. CCI + sgp130-Fc mice had shorter platform latencies and path lengths and had decreased peripheral zone time, indicating a therapeutic benefit of sgp130-Fc after injury on learning and anxiety. Interestingly, Sham + sgp130-Fc mice had shorter platform latencies, path lengths and peripheral zone times than Sham + VEH mice, suggesting a beneficial effect of sgp130-Fc, independent of injury. CCI + VEH mice had increased brain IL-6 and decreased sgp130 levels versus Sham + VEH and Sham + sgp130-Fc mice. There was no treatment effect on IL-6, sIL6-R or sgp130 in Sham + VEH versus Sham + sgp130-Fc mice. There was also no treatment effect on IL-6 in CCI + VEH versus CCI + sgp130-Fc mice. However, CCI + sgp130-Fc mice had increased sIL-6R and sgp130 versus CCI + VEH mice, demonstrating sgp130-Fc treatment effects on brain biomarkers. Inflammatory chemokines (MIP-1β, IP-10, MIG) were increased in CCI + VEH mice versus Sham + VEH and Sham + sgp130-Fc mice. However, CCI + sgp130-Fc mice had decreased chemokine levels versus CCI + VEH mice. IL-6 positively correlated, while sgp130 negatively correlated, with chemokine levels. Overall, we found that systemic sgp130-Fc treatment after CCI improved learning, decreased anxiety and reduced CCI-induced brain chemokines. Future studies will explore sex-specific dosing and treatment mechanisms for sgp130-Fc therapy.
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Affiliation(s)
- Ian G Gober
- Department of Physical Medicine and Rehabilitation, School of Medicine, University of Pittsburgh, 3471 Fifth Avenue, Suite 910, Pittsburgh, PA, 15213, USA
- Safar Center for Resuscitation Research, John G. Rangos Research Center, Pittsburgh, PA, USA
| | - Ashley L Russell
- Department of Physical Medicine and Rehabilitation, School of Medicine, University of Pittsburgh, 3471 Fifth Avenue, Suite 910, Pittsburgh, PA, 15213, USA
- Safar Center for Resuscitation Research, John G. Rangos Research Center, Pittsburgh, PA, USA
| | - Tyler J Shick
- Department of Physical Medicine and Rehabilitation, School of Medicine, University of Pittsburgh, 3471 Fifth Avenue, Suite 910, Pittsburgh, PA, 15213, USA
- Safar Center for Resuscitation Research, John G. Rangos Research Center, Pittsburgh, PA, USA
| | - Vincent A Vagni
- Safar Center for Resuscitation Research, John G. Rangos Research Center, Pittsburgh, PA, USA
- Department of Critical Care Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jenna C Carlson
- Department of Biostatistics, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Human Genetics, School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - Patrick M Kochanek
- Safar Center for Resuscitation Research, John G. Rangos Research Center, Pittsburgh, PA, USA
- Department of Critical Care Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Amy K Wagner
- Department of Physical Medicine and Rehabilitation, School of Medicine, University of Pittsburgh, 3471 Fifth Avenue, Suite 910, Pittsburgh, PA, 15213, USA.
- Safar Center for Resuscitation Research, John G. Rangos Research Center, Pittsburgh, PA, USA.
- Center for Neuroscience, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.
- Department of Neuroscience, School of Arts and Sciences, University of Pittsburgh, Pittsburgh, PA, USA.
- Clinical and Translational Science Institute, University of Pittsburgh, Pittsburgh, PA, USA.
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Vertes RP, Linley SB, Rojas AKP. Structural and functional organization of the midline and intralaminar nuclei of the thalamus. Front Behav Neurosci 2022; 16:964644. [PMID: 36082310 PMCID: PMC9445584 DOI: 10.3389/fnbeh.2022.964644] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 07/07/2022] [Indexed: 12/03/2022] Open
Abstract
The midline and intralaminar nuclei of the thalamus form a major part of the "limbic thalamus;" that is, thalamic structures anatomically and functionally linked with the limbic forebrain. The midline nuclei consist of the paraventricular (PV) and paratenial nuclei, dorsally and the rhomboid and nucleus reuniens (RE), ventrally. The rostral intralaminar nuclei (ILt) consist of the central medial (CM), paracentral (PC) and central lateral (CL) nuclei. We presently concentrate on RE, PV, CM and CL nuclei of the thalamus. The nucleus reuniens receives a diverse array of input from limbic-related sites, and predominantly projects to the hippocampus and to "limbic" cortices. The RE participates in various cognitive functions including spatial working memory, executive functions (attention, behavioral flexibility) and affect/fear behavior. The PV receives significant limbic-related afferents, particularly the hypothalamus, and mainly distributes to "affective" structures of the forebrain including the bed nucleus of stria terminalis, nucleus accumbens and the amygdala. Accordingly, PV serves a critical role in "motivated behaviors" such as arousal, feeding/consummatory behavior and drug addiction. The rostral ILt receives both limbic and sensorimotor-related input and distributes widely over limbic and motor regions of the frontal cortex-and throughout the dorsal striatum. The intralaminar thalamus is critical for maintaining consciousness and directly participates in various sensorimotor functions (visuospatial or reaction time tasks) and cognitive tasks involving striatal-cortical interactions. As discussed herein, while each of the midline and intralaminar nuclei are anatomically and functionally distinct, they collectively serve a vital role in several affective, cognitive and executive behaviors - as major components of a brainstem-diencephalic-thalamocortical circuitry.
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Affiliation(s)
- Robert P. Vertes
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL, United States
- Department of Psychology, Florida Atlantic University, Boca Raton, FL, United States
| | - Stephanie B. Linley
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL, United States
- Department of Psychology, Florida Atlantic University, Boca Raton, FL, United States
- Department of Psychological Science, University of North Georgia, Dahlonega, GA, United States
| | - Amanda K. P. Rojas
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL, United States
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Torromino G, Loffredo V, Cavezza D, Sonsini G, Esposito F, Crevenna AH, Gioffrè M, De Risi M, Treves A, Griguoli M, De Leonibus E. Thalamo-hippocampal pathway regulates incidental memory capacity in mice. Nat Commun 2022; 13:4194. [PMID: 35859057 PMCID: PMC9300669 DOI: 10.1038/s41467-022-31781-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 07/04/2022] [Indexed: 12/27/2022] Open
Abstract
Incidental memory can be challenged by increasing either the retention delay or the memory load. The dorsal hippocampus (dHP) appears to help with both consolidation from short-term (STM) to long-term memory (LTM), and higher memory loads, but the mechanism is not fully understood. Here we find that female mice, despite having the same STM capacity of 6 objects and higher resistance to distraction in our different object recognition task (DOT), when tested over 1 h or 24 h delays appear to transfer to LTM only 4 objects, whereas male mice have an STM capacity of 6 objects in this task. In male mice the dHP shows greater activation (as measured by c-Fos expression), whereas female mice show greater activation of the ventral midline thalamus (VMT). Optogenetic inhibition of the VMT-dHP pathway during off-line memory consolidation enables 6-object LTM retention in females, while chemogenetic VMT-activation impairs it in males. Thus, removing or enhancing sub-cortical inhibitory control over the hippocampus leads to differences in incidental memory. Incidental memory is affected by retention delay, and by memory load. Here the authors show that female and male mice process high memory load through different activation of thalamic-cortical pathways, that makes their incidental memory resistant to distraction and to memory decay, respectively.
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Affiliation(s)
- G Torromino
- Telethon Institute of Genetics and Medicine, Telethon Foundation, Pozzuoli (Naples), Italy.,Institute of Biochemistry and Cell Biology (IBBC), National Research Council, Monterotondo (Rome), Italy
| | - V Loffredo
- Telethon Institute of Genetics and Medicine, Telethon Foundation, Pozzuoli (Naples), Italy.,Institute of Biochemistry and Cell Biology (IBBC), National Research Council, Monterotondo (Rome), Italy.,PhD Program in Behavioral Neuroscience, Sapienza University of Rome, Rome, Italy
| | - D Cavezza
- Institute of Biochemistry and Cell Biology (IBBC), National Research Council, Monterotondo (Rome), Italy
| | - G Sonsini
- Institute of Biochemistry and Cell Biology (IBBC), National Research Council, Monterotondo (Rome), Italy
| | - F Esposito
- Telethon Institute of Genetics and Medicine, Telethon Foundation, Pozzuoli (Naples), Italy
| | - A H Crevenna
- Neurobiology and Epigenetics Unit, European Molecular Biology Laboratory (EMBL), Monterotondo (Rome), Italy
| | - M Gioffrè
- Institute of Applied Sciences and Intelligent Systems (ISASI), National Research Council, Naples, Italy
| | - M De Risi
- Telethon Institute of Genetics and Medicine, Telethon Foundation, Pozzuoli (Naples), Italy.,Institute of Biochemistry and Cell Biology (IBBC), National Research Council, Monterotondo (Rome), Italy
| | - A Treves
- SISSA - Cognitive Neuroscience, Trieste, Italy
| | - M Griguoli
- European Brain Research Institute (EBRI), Rome, Italy.,Institute of Molecular Biology and Pathology (IBPM), National Research Council, Rome, Italy
| | - E De Leonibus
- Telethon Institute of Genetics and Medicine, Telethon Foundation, Pozzuoli (Naples), Italy. .,Institute of Biochemistry and Cell Biology (IBBC), National Research Council, Monterotondo (Rome), Italy.
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The anterior thalamic nuclei: core components of a tripartite episodic memory system. Nat Rev Neurosci 2022; 23:505-516. [PMID: 35478245 DOI: 10.1038/s41583-022-00591-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/25/2022] [Indexed: 12/13/2022]
Abstract
Standard models of episodic memory focus on hippocampal-parahippocampal interactions, with the neocortex supplying sensory information and providing a final repository of mnemonic representations. However, recent advances have shown that other regions make distinct and equally critical contributions to memory. In particular, there is growing evidence that the anterior thalamic nuclei have a number of key cognitive functions that support episodic memory. In this article, we describe these findings and argue for a core, tripartite memory system, comprising a 'temporal lobe' stream (centred on the hippocampus) and a 'medial diencephalic' stream (centred on the anterior thalamic nuclei) that together act on shared cortical areas. We demonstrate how these distributed brain regions form complementary and necessary partnerships in episodic memory formation.
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Cosgrove ME, Saadon JR, Mikell CB, Stefancin PL, Alkadaa L, Wang Z, Saluja S, Servider J, Razzaq B, Huang C, Mofakham S. Thalamo-Prefrontal Connectivity Correlates With Early Command-Following After Severe Traumatic Brain Injury. Front Neurol 2022; 13:826266. [PMID: 35250829 PMCID: PMC8895046 DOI: 10.3389/fneur.2022.826266] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/25/2022] [Indexed: 12/19/2022] Open
Abstract
Recovery of consciousness after traumatic brain injury (TBI) is heterogeneous and difficult to predict. Structures such as the thalamus and prefrontal cortex are thought to be important in facilitating consciousness. We sought to investigate whether the integrity of thalamo-prefrontal circuits, assessed via diffusion tensor imaging (DTI), was associated with the return of goal-directed behavior after severe TBI. We classified a cohort of severe TBI patients (N = 25, 20 males) into Early and Late/Never outcome groups based on their ability to follow commands within 30 days post-injury. We assessed connectivity between whole thalamus, and mediodorsal thalamus (MD), to prefrontal cortex (PFC) subregions including dorsolateral PFC (dlPFC), medial PFC (mPFC), anterior cingulate (ACC), and orbitofrontal (OFC) cortices. We found that the integrity of thalamic projections to PFC subregions (L OFC, L and R ACC, and R mPFC) was significantly associated with Early command-following. This association persisted when the analysis was restricted to prefrontal-mediodorsal (MD) thalamus connectivity. In contrast, dlPFC connectivity to thalamus was not significantly associated with command-following. Using the integrity of thalamo-prefrontal connections, we created a linear regression model that demonstrated 72% accuracy in predicting command-following after a leave-one-out analysis. Together, these data support a role for thalamo-prefrontal connectivity in the return of goal-directed behavior following TBI.
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Affiliation(s)
- Megan E. Cosgrove
- Department of Neurosurgery, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY, United States
| | - Jordan R. Saadon
- Department of Neurosurgery, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY, United States
| | - Charles B. Mikell
- Department of Neurosurgery, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY, United States
| | | | - Leor Alkadaa
- Department of Neurosurgery, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY, United States
| | - Zhe Wang
- Department of Neurosurgery, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY, United States
| | - Sabir Saluja
- Department of Neurosurgery, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY, United States
| | - John Servider
- Department of Neurosurgery, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY, United States
| | - Bayan Razzaq
- Department of Neurosurgery, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY, United States
| | - Chuan Huang
- Department of Radiology, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY, United States
- Department of Psychiatry, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY, United States
| | - Sima Mofakham
- Department of Neurosurgery, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY, United States
- Department of Electrical and Computer Engineering, Stony Brook University, Stony Brook, NY, United States
- *Correspondence: Sima Mofakham
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8
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Schwabe MR, Lincoln CM, Ivers MM, Frick KM. Chemogenetic inactivation of the nucleus reuniens impairs object placement memory in female mice. Neurobiol Learn Mem 2021; 185:107521. [PMID: 34536525 PMCID: PMC8595750 DOI: 10.1016/j.nlm.2021.107521] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 08/17/2021] [Accepted: 09/10/2021] [Indexed: 11/30/2022]
Abstract
Episodic memory is a complex process requiring input from several regions of the brain. Emerging evidence suggests that coordinated activity between the dorsal hippocampus (DH) and medial prefrontal cortex (mPFC) is required for episodic memory consolidation. However, the mechanisms through which the DH and mPFC interact to promote memory consolidation remain poorly understood. A growing body of research suggests that the nucleus reuniens of the thalamus (RE) is one of several structures that facilitate communication between the DH and mPFC during memory and may do so through bidirectional excitatory projections to both regions. Furthermore, recent work from other labs indicates that the RE is necessary for spatial working memory. However, it is not clear to what extent the RE is necessary for memory of object locations. The goal of this study was to determine whether activity in the RE is necessary for spatial memory as measured by the object placement (OP) task in female mice. A kappa-opioid receptor DREADD (KORD) virus was used to inactivate excitatory neurons in the RE pre- or post-training to establish a role for the RE in spatial memory acquisition and consolidation, respectively. RE inactivation prior to, or immediately after, object training blocked OP memory formation relative to chance and to control mice. Moreover, expression of the immediate early gene EGR-1 was reduced in the RE 1 hour after an object training trial, supporting the conclusion that reduced neuronal activity in the RE impairs the formation of object location memories. In summary, the findings of this study support a key role for the RE in spatial memory acquisition and consolidation.
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Affiliation(s)
- Miranda R Schwabe
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, United States
| | - Carnita M Lincoln
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, United States
| | - Margaret M Ivers
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, United States
| | - Karyn M Frick
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, United States.
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9
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Savage LM, Nunes PT, Gursky ZH, Milbocker KA, Klintsova AY. Midline Thalamic Damage Associated with Alcohol-Use Disorders: Disruption of Distinct Thalamocortical Pathways and Function. Neuropsychol Rev 2021; 31:447-471. [PMID: 32789537 PMCID: PMC7878584 DOI: 10.1007/s11065-020-09450-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 07/30/2020] [Indexed: 02/07/2023]
Abstract
The thalamus, a significant part of the diencephalon, is a symmetrical and bilateral central brain structure. The thalamus is subdivided into three major groups of nuclei based on their function: sensorimotor nuclei (or principal/relay nuclei), limbic nuclei and nuclei bridging these two domains. Anatomically, nuclei within the thalamus are described by their location, such as anterior, medial, lateral, ventral, and posterior. In this review, we summarize the role of medial and midline thalamus in cognition, ranging from learning and memory to flexible adaptation. We focus on the discoveries in animal models of alcohol-related brain damage, which identify the loss of neurons in the medial and midline thalamus as drivers of cognitive dysfunction associated with alcohol use disorders. Models of developmental ethanol exposure and models of adult alcohol-related brain damage and are compared and contrasted, and it was revealed that there are similar (anterior thalamus) and different (intralaminar [adult exposure] versus ventral midline [developmental exposure]) thalamic pathology, as well as disruptions of thalamo-hippocampal and thalamo-cortical circuits. The final part of the review summarizes approaches to recover alcohol-related brain damage and cognitive and behavioral outcomes. These approaches include pharmacological, nutritional and behavioral interventions that demonstrated the potential to mitigate alcohol-related damage. In summary, the medial/midline thalamus is a significant contributor to cognition function, which is also sensitive to alcohol-related brain damage across the life span, and plays a role in alcohol-related cognitive dysfunction.
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Affiliation(s)
- Lisa M Savage
- Developmental Ethanol Alcohol Research Center, Department of Psychology, Binghamton University, State University of New York, Binghamton, NY, 13902-6000, USA.
| | - Polliana T Nunes
- Developmental Ethanol Alcohol Research Center, Department of Psychology, Binghamton University, State University of New York, Binghamton, NY, 13902-6000, USA
| | - Zachary H Gursky
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE, USA
| | - Katrina A Milbocker
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE, USA
| | - Anna Y Klintsova
- Department of Psychological and Brain Sciences, University of Delaware, Newark, DE, USA
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10
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Cassel JC, Ferraris M, Quilichini P, Cholvin T, Boch L, Stephan A, Pereira de Vasconcelos A. The reuniens and rhomboid nuclei of the thalamus: A crossroads for cognition-relevant information processing? Neurosci Biobehav Rev 2021; 126:338-360. [PMID: 33766671 DOI: 10.1016/j.neubiorev.2021.03.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 03/17/2021] [Accepted: 03/17/2021] [Indexed: 01/29/2023]
Abstract
Over the past twenty years, the reuniens and rhomboid (ReRh) nuclei, which constitute the ventral midline thalamus, have received constantly growing attention. Since our first review article about the functional contributions of ReRh nuclei (Cassel et al., 2013), numerous (>80) important papers have extended anatomical knowledge, including at a developmental level, introduced new and very original electrophysiological insights on ReRh functions, and brought novel results on cognitive and non-cognitive implications of the ReRh. The current review will cover these recent articles, more on Re than on Rh, and their contribution will be approached according to their affiliation with work before 2013. These neuroanatomical, electrophysiological or behavioral findings appear coherent and point to the ReRh nuclei as two major components of a multistructural system supporting numerous cognitive (and non-cognitive) functions. They gate the flow of information, perhaps especially from the medial prefrontal cortex to the hippocampus and back, and coordinate activity and processing across these two (and possibly other) brain regions of major cognitive relevance.
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Affiliation(s)
- Jean-Christophe Cassel
- Laboratoire de Neurosciences Cognitives et Adaptatives, Université de Strasbourg, F-67000 Strasbourg, France; LNCA, UMR 7364 - CNRS, F-67000 Strasbourg, France.
| | - Maëva Ferraris
- Aix Marseille Université, INSERM, INS, Inst Neurosci Syst, Marseille, France
| | - Pascale Quilichini
- Aix Marseille Université, INSERM, INS, Inst Neurosci Syst, Marseille, France
| | - Thibault Cholvin
- Institute for Physiology I, University Clinics Freiburg, 79104 Freiburg, Germany
| | - Laurine Boch
- Laboratoire de Neurosciences Cognitives et Adaptatives, Université de Strasbourg, F-67000 Strasbourg, France; LNCA, UMR 7364 - CNRS, F-67000 Strasbourg, France
| | - Aline Stephan
- Laboratoire de Neurosciences Cognitives et Adaptatives, Université de Strasbourg, F-67000 Strasbourg, France; LNCA, UMR 7364 - CNRS, F-67000 Strasbourg, France
| | - Anne Pereira de Vasconcelos
- Laboratoire de Neurosciences Cognitives et Adaptatives, Université de Strasbourg, F-67000 Strasbourg, France; LNCA, UMR 7364 - CNRS, F-67000 Strasbourg, France
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11
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Ferraris M, Cassel JC, Pereira de Vasconcelos A, Stephan A, Quilichini PP. The nucleus reuniens, a thalamic relay for cortico-hippocampal interaction in recent and remote memory consolidation. Neurosci Biobehav Rev 2021; 125:339-354. [PMID: 33631314 DOI: 10.1016/j.neubiorev.2021.02.025] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 02/15/2021] [Accepted: 02/16/2021] [Indexed: 12/12/2022]
Abstract
The consolidation of declarative memories is believed to occur mostly during sleep and involves a dialogue between two brain regions, the hippocampus and the medial prefrontal cortex. The information encoded during experience by neuronal assemblies is replayed during sleep leading to the progressive strengthening and integration of the memory trace in the prefrontal cortex. The gradual transfer of information from the hippocampus to the medial prefrontal cortex for long-term storage requires the synchronization of cortico-hippocampal networks by different oscillations, like ripples, spindles, and slow oscillations. Recent studies suggest the involvement of a third partner, the nucleus reuniens, in memory consolidation. Its bidirectional connections with the hippocampus and medial prefrontal cortex place the reuniens in a key position to relay information between the two structures. Indeed, many topical works reveal the original role that the nucleus reuniens occupies in different recent and remote memories consolidation. This review aimed to examine these contributions, as well as its functional embedment in this complex memory network, and provide some insights on the possible mechanisms.
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Affiliation(s)
- Maëva Ferraris
- Aix Marseille Univ, INSERM, INS, Inst Neurosci Syst, Marseille, France
| | - Jean-Christophe Cassel
- Laboratoire De Neurosciences Cognitives Et Adaptatives, Université De Strasbourg, F-67000, Strasbourg, France; LNCA, UMR 7364 - CNRS, F-67000, Strasbourg, France
| | - Anne Pereira de Vasconcelos
- Laboratoire De Neurosciences Cognitives Et Adaptatives, Université De Strasbourg, F-67000, Strasbourg, France; LNCA, UMR 7364 - CNRS, F-67000, Strasbourg, France
| | - Aline Stephan
- Laboratoire De Neurosciences Cognitives Et Adaptatives, Université De Strasbourg, F-67000, Strasbourg, France; LNCA, UMR 7364 - CNRS, F-67000, Strasbourg, France
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12
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Hatzipantelis C, Langiu M, Vandekolk TH, Pierce TL, Nithianantharajah J, Stewart GD, Langmead CJ. Translation-Focused Approaches to GPCR Drug Discovery for Cognitive Impairments Associated with Schizophrenia. ACS Pharmacol Transl Sci 2020; 3:1042-1062. [PMID: 33344888 PMCID: PMC7737210 DOI: 10.1021/acsptsci.0c00117] [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: 08/20/2020] [Indexed: 01/07/2023]
Abstract
There are no effective therapeutics for cognitive impairments associated with schizophrenia (CIAS), which includes deficits in executive functions (working memory and cognitive flexibility) and episodic memory. Compounds that have entered clinical trials are inadequate in terms of efficacy and/or tolerability, highlighting a clear translational bottleneck and a need for a cohesive preclinical drug development strategy. In this review we propose hippocampal-prefrontal-cortical (HPC-PFC) circuitry underlying CIAS-relevant cognitive processes across mammalian species as a target source to guide the translation-focused discovery and development of novel, procognitive agents. We highlight several G protein-coupled receptors (GPCRs) enriched within HPC-PFC circuitry as therapeutic targets of interest, including noncanonical approaches (biased agonism and allosteric modulation) to conventional clinical targets, such as dopamine and muscarinic acetylcholine receptors, along with prospective novel targets, including the orphan receptors GPR52 and GPR139. We also describe the translational limitations of popular preclinical cognition tests and suggest touchscreen-based assays that probe cognitive functions reliant on HPC-PFC circuitry and reflect tests used in the clinic, as tests of greater translational relevance. Combining pharmacological and behavioral testing strategies based in HPC-PFC circuit function creates a cohesive, translation-focused approach to preclinical drug development that may improve the translational bottleneck currently hindering the development of treatments for CIAS.
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Affiliation(s)
- Cassandra
J. Hatzipantelis
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Monica Langiu
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Teresa H. Vandekolk
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Tracie L. Pierce
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Jess Nithianantharajah
- Florey
Institute of Neuroscience
and Mental Health, University of Melbourne, Parkville, Victoria 3052, Australia
| | - Gregory D. Stewart
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Christopher J. Langmead
- Drug
Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
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13
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Mathiasen ML, O'Mara SM, Aggleton JP. The anterior thalamic nuclei and nucleus reuniens: So similar but so different. Neurosci Biobehav Rev 2020; 119:268-280. [PMID: 33069688 PMCID: PMC7738755 DOI: 10.1016/j.neubiorev.2020.10.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 07/26/2020] [Accepted: 10/05/2020] [Indexed: 12/04/2022]
Abstract
Two thalamic sites are of especial significance for understanding hippocampal - diencephalic interactions: the anterior thalamic nuclei and nucleus reuniens. Both nuclei have dense, direct interconnections with the hippocampal formation, and both are directly connected with many of the same cortical and subcortical areas. These two thalamic sites also contain neurons responsive to spatial stimuli while lesions within these two same areas can disrupt spatial learning tasks that are hippocampal dependent. Despite these many similarities, closer analysis reveals important differences in the details of their connectivity and the behavioural impact of lesions in these two thalamic sites. These nuclei play qualitatively different roles that largely reflect the contrasting relative importance of their medial frontal cortex interactions (nucleus reuniens) compared with their retrosplenial, cingulate, and mammillary body interactions (anterior thalamic nuclei). While the anterior thalamic nuclei are critical for multiple aspects of hippocampal spatial encoding and performance, nucleus reuniens contributes, as required, to aid cognitive control and help select correct from competing memories.
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Affiliation(s)
- Mathias L Mathiasen
- School of Psychology, Cardiff University, 70 Park Place, Cardiff, CF10 3AT, Wales, UK
| | - Shane M O'Mara
- School of Psychology and Institute of Neuroscience, Trinity College, Dublin, Ireland
| | - John P Aggleton
- School of Psychology, Cardiff University, 70 Park Place, Cardiff, CF10 3AT, Wales, UK.
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14
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Adler SM, Girotti M, Morilak DA. Optogenetically-induced long term depression in the rat orbitofrontal cortex ameliorates stress-induced reversal learning impairment. Neurobiol Stress 2020; 13:100258. [PMID: 33344713 PMCID: PMC7739068 DOI: 10.1016/j.ynstr.2020.100258] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 10/12/2020] [Accepted: 10/15/2020] [Indexed: 12/02/2022] Open
Abstract
Cognitive flexibility is a higher-order executive function that requires plasticity in neuronal circuits of the prefrontal cortex. Deficits in cognitive flexibility are prominent in a variety of psychiatric disorders, such as major depression, obsessive-compulsive disorder, and posttraumatic stress disorder. Chronic stress induces deficits in cognitive flexibility, perhaps through effects on plasticity, but the mechanism is not well understood. Previous work has demonstrated that stress reduces activity and dendritic elaboration in the medial prefrontal cortex (mPFC). In contrast, stress appears to increase dendritic elaboration in the orbitofrontal cortex (OFC). This suggests that there may be a differential effect of stress on plasticity in different prefrontal cortical areas. To test this hypothesis, we examined the effects of inducing plasticity optogenetically in the OFC on reversal learning, an OFC-mediated form of cognitive flexibility, in stressed and non-stressed rats. Inducing opto-LTD in the projection from mediodorsal thalamus to OFC ameliorated reversal learning deficits in rats exposed to chronic intermittent cold (CIC) stress. Additionally, we found that inducing opto-LTP in non-stressed rats produced deficits in reversal learning similar to those seen in rats after CIC stress. Finally, CIC stress produced complex subregion-specific changes in dendritic material and spine subtype composition in the OFC. These results indicate that the effects of stress on plasticity in the OFC are distinct from those in the mPFC, and that the PFC should therefore not be treated as a homogenous region in studying either stress effects or potential treatments for stress-related psychiatric disorders.
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Affiliation(s)
- Samantha M Adler
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, 7703 Floyd Curl Dr, San Antonio, TX, 78229, USA
| | - Milena Girotti
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, 7703 Floyd Curl Dr, San Antonio, TX, 78229, USA
| | - David A Morilak
- Department of Pharmacology and Center for Biomedical Neuroscience, UT Health San Antonio, 7703 Floyd Curl Dr, San Antonio, TX, 78229, USA.,South Texas Veterans Health Care System, San Antonio, TX, 78229, USA
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15
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Jia Q, Zhang Y, Liu S, Li Z, Zhou F, Shao L, Feng C, Fan G. Analysis of search strategies for evaluating low-dose heavy metal mixture induced cognitive deficits in rats: An early sensitive toxicological approach. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 202:110900. [PMID: 32593095 DOI: 10.1016/j.ecoenv.2020.110900] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 06/12/2020] [Accepted: 06/14/2020] [Indexed: 06/11/2023]
Abstract
Heavy metals such as lead (Pb), cadmium (Cd), and mercury (Hg) are representative neurotoxicological contaminants that can evoke cognitive dysfunctions. Low levels of these contaminants can be detected simultaneously in the human blood. In our previous study, behavioral performances were markedly impaired by exposure to these heavy metal mixtures (MM) at low levels. However, the aspects of cognitive functions involved are not well understood. Here, we further analyzed search strategies using a new algorithm named Morris water maze-unbiased strategy classification (MUST-C). Rat pups were co-exposed to low doses of Pb, Cd, and Hg during the embryonic and lactation stage. MM exposure at low doses, similar to those found in the general population, impaired search strategies even though their latency and path length were not affected in the Morris water maze task. MM-exposed rats preferred to use more directionless repetition strategies and less target orientation strategies than did vehicle-exposed animals in a dose-dependent manner. In addition, thionine staining and electron microscopy further revealed that MM exposure induced dose-dependent search strategy related place cell injures in the hippocampal CA1 and CA3 regions. These results demonstrate that the use of suboptimal search strategies underlies the early cognitive deficits in rats exposed to low doses of MM. The current study determined that search strategy analysis might be a novel sensitive assessment method for evaluating in the neurobehavioral toxicity.
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Affiliation(s)
- Qiyue Jia
- Department of Occupational Health and Toxicology, School of Public Health, Nanchang University, Nanchang, 330006, PR China; Jiangxi Provincial Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, PR China
| | - Yuanyuan Zhang
- Department of Occupational Health and Toxicology, School of Public Health, Nanchang University, Nanchang, 330006, PR China; Jiangxi Provincial Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, PR China
| | - Sisi Liu
- Department of Occupational Health and Toxicology, School of Public Health, Nanchang University, Nanchang, 330006, PR China; Jiangxi Provincial Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, PR China
| | - Zongguang Li
- Department of Occupational Health and Toxicology, School of Public Health, Nanchang University, Nanchang, 330006, PR China; Jiangxi Provincial Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, PR China
| | - Fankun Zhou
- Department of Occupational Health and Toxicology, School of Public Health, Nanchang University, Nanchang, 330006, PR China; Jiangxi Provincial Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, PR China
| | - Lijian Shao
- Department of Occupational Health and Toxicology, School of Public Health, Nanchang University, Nanchang, 330006, PR China; Jiangxi Provincial Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, PR China
| | - Chang Feng
- Department of Occupational Health and Toxicology, School of Public Health, Nanchang University, Nanchang, 330006, PR China; Jiangxi Provincial Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, PR China
| | - Guangqin Fan
- Department of Occupational Health and Toxicology, School of Public Health, Nanchang University, Nanchang, 330006, PR China; Jiangxi Provincial Key Laboratory of Preventive Medicine, Nanchang University, Nanchang, 330006, PR China.
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16
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Long-term potentiation of the nucleus reuniens and entorhinal cortex to CA1 distal dendritic synapses in mice. Brain Struct Funct 2020; 225:1817-1838. [DOI: 10.1007/s00429-020-02095-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 05/31/2020] [Indexed: 02/07/2023]
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17
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Hasz BM, Redish AD. Dorsomedial prefrontal cortex and hippocampus represent strategic context even while simultaneously changing representation throughout a task session. Neurobiol Learn Mem 2020; 171:107215. [PMID: 32276121 DOI: 10.1016/j.nlm.2020.107215] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 03/07/2020] [Accepted: 03/18/2020] [Indexed: 02/06/2023]
Abstract
Dorsomedial prefrontal cortex (dmPFC) and hippocampus (HPC) are thought to play complementary roles in a spatial working memory and decision-making network, where spatial information from HPC informs representations in dmPFC, and contextual information from dmPFC biases how HPC recalls that information. We recorded simultaneously from neural ensembles in rodent dmPFC and HPC as rats performed a rule-switching task, and found that ensembles in dmPFC and HPC simultaneously encoded task contingencies and other time-varying information. While ensembles in HPC transitioned to represent new contingencies at the same time as rats updated their strategies to be consistent with the new contingency, dmPFC ensembles transitioned earlier. Neural representations of other time-varying information also changed faster in dmPFC than in HPC. Our results suggest that HPC and dmPFC represent contingencies while simultaneously representing other information which changes over time, and that this contextual information is integrated into hippocampal representations more slowly than in dmPFC.
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Affiliation(s)
- Brendan M Hasz
- Graduate Program in Neuroscience, University of Minnesota Twin Cities, Minneapolis, MN, USA
| | - A David Redish
- Department of Neuroscience, University of Minnesota Twin Cities, Minneapolis, MN, USA.
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18
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Lumley L, Miller D, Muse WT, Marrero‐Rosado B, de Araujo Furtado M, Stone M, McGuire J, Whalley C. Neurosteroid and benzodiazepine combination therapy reduces status epilepticus and long-term effects of whole-body sarin exposure in rats. Epilepsia Open 2019; 4:382-396. [PMID: 31440720 PMCID: PMC6698686 DOI: 10.1002/epi4.12344] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 04/26/2019] [Accepted: 05/19/2019] [Indexed: 01/04/2023] Open
Abstract
OBJECTIVE Our objective was to evaluate the protective efficacy of the neurosteroid pregnanolone (3α-hydroxy-5β pregnan-20-one), a GABAA receptor-positive allosteric modulator, as an adjunct to benzodiazepine therapy against the chemical warfare nerve agent (CWNA) sarin (GB), using whole-body exposure, an operationally relevant route of exposure to volatile GB. METHODS Rats implanted with telemetry transmitters for the continuous measurement of cortical electroencephalographic (EEG) activity were exposed for 60 minutes to 3.0 LCt50 of GB via whole-body exposure. At the onset of toxic signs, rats were administered an intramuscular injection of atropine sulfate (2 mg/kg) and the oxime HI-6 (93.6 mg/kg) to increase survival rate and, 30 minutes after seizure onset, treated subcutaneously with diazepam (10 mg/kg) and intravenously with pregnanolone (4 mg/kg) or vehicle. Animals were evaluated for GB-induced status epilepticus (SE), spontaneous recurrent seizures (SRS), impairment in spatial memory acquisition, and brain pathology, and treatment groups were compared. RESULTS Delayed dual therapy with pregnanolone and diazepam reduced time in SE in GB-exposed rats compared to those treated with delayed diazepam monotherapy. The combination therapy of pregnanolone with diazepam also prevented impairment in the Morris water maze and reduced the neuronal loss and neuronal degeneration, evaluated at one and three months after exposure. SIGNIFICANCE Neurosteroid administration as an adjunct to benzodiazepine therapy offers an effective means to treat benzodiazepine-refractory SE, such as occurs following delayed treatment of GB exposure. This study is the first to present data on the efficacy of delayed pregnanolone and diazepam dual therapy in reducing seizure activity, performance deficits and brain pathology following an operationally relevant route of exposure to GB and supports the use of a neurosteroid as an adjunct to standard anticonvulsant therapy for the treatment of CWNA-induced SE.
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Affiliation(s)
- Lucille Lumley
- US Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMaryland
| | - Dennis Miller
- US Army Combat Capabilities Development Command Chemical Biological CenterAberdeen Proving GroundMaryland
| | - William T. Muse
- US Army Combat Capabilities Development Command Chemical Biological CenterAberdeen Proving GroundMaryland
| | - Brenda Marrero‐Rosado
- US Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMaryland
| | | | - Michael Stone
- US Army Medical Research Institute of Chemical DefenseAberdeen Proving GroundMaryland
| | - Jeffrey McGuire
- US Army Combat Capabilities Development Command Chemical Biological CenterAberdeen Proving GroundMaryland
| | - Christopher Whalley
- US Army Combat Capabilities Development Command Chemical Biological CenterAberdeen Proving GroundMaryland
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19
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Jayachandran M, Linley SB, Schlecht M, Mahler SV, Vertes RP, Allen TA. Prefrontal Pathways Provide Top-Down Control of Memory for Sequences of Events. Cell Rep 2019; 28:640-654.e6. [PMID: 31315044 PMCID: PMC6662648 DOI: 10.1016/j.celrep.2019.06.053] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 05/19/2019] [Accepted: 06/14/2019] [Indexed: 11/30/2022] Open
Abstract
We remember our lives as sequences of events, but it is unclear how these memories are controlled during retrieval. In rats, the medial prefrontal cortex (mPFC) is positioned to influence sequence memory through extensive top-down inputs to regions heavily interconnected with the hippocampus, notably the nucleus reuniens of the thalamus (RE) and perirhinal cortex (PER). Here, we used an hM4Di synaptic-silencing approach to test our hypothesis that specific mPFC→RE and mPFC→PER projections regulate sequence memory retrieval. First, we found non-overlapping populations of mPFC cells project to RE and PER. Second, suppressing mPFC activity impaired sequence memory. Third, inhibiting mPFC→RE and mPFC→PER pathways effectively abolished sequence memory. Finally, a sequential lag analysis showed that the mPFC→RE pathway contributes to a working memory retrieval strategy, whereas the mPFC→PER pathway supports a temporal context memory retrieval strategy. These findings demonstrate that mPFC→RE and mPFC→PER pathways serve as top-down mechanisms that control distinct sequence memory retrieval strategies.
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Affiliation(s)
- Maanasa Jayachandran
- Cognitive Neuroscience Program, Department of Psychology, Florida International University, Miami, FL 33199, USA
| | - Stephanie B Linley
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL 33431, USA
| | - Maximilian Schlecht
- Cognitive Neuroscience Program, Department of Psychology, Florida International University, Miami, FL 33199, USA
| | - Stephen V Mahler
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA
| | - Robert P Vertes
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL 33431, USA
| | - Timothy A Allen
- Cognitive Neuroscience Program, Department of Psychology, Florida International University, Miami, FL 33199, USA; Department of Environmental Health Sciences, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL 33199, USA.
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20
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Dolleman-van der Weel MJ, Griffin AL, Ito HT, Shapiro ML, Witter MP, Vertes RP, Allen TA. The nucleus reuniens of the thalamus sits at the nexus of a hippocampus and medial prefrontal cortex circuit enabling memory and behavior. Learn Mem 2019; 26:191-205. [PMID: 31209114 PMCID: PMC6581009 DOI: 10.1101/lm.048389.118] [Citation(s) in RCA: 118] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 04/16/2019] [Indexed: 12/12/2022]
Abstract
The nucleus reuniens of the thalamus (RE) is a key component of an extensive network of hippocampal and cortical structures and is a fundamental substrate for cognition. A common misconception is that RE is a simple relay structure. Instead, a better conceptualization is that RE is a critical component of a canonical higher-order cortico-thalamo-cortical circuit that supports communication between the medial prefrontal cortex (mPFC) and the hippocampus (HC). RE dysfunction is implicated in several clinical disorders including, but not limited to Alzheimer's disease, schizophrenia, and epilepsy. Here, we review key anatomical and physiological features of the RE based primarily on studies in rodents. We present a conceptual model of RE circuitry within the mPFC-RE-HC system and speculate on the computations RE enables. We review the rapidly growing literature demonstrating that RE is critical to, and its neurons represent, aspects of behavioral tasks that place demands on memory focusing on its role in navigation, spatial working memory, the temporal organization of memory, and executive functions.
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Affiliation(s)
- Margriet J Dolleman-van der Weel
- Department of Anatomy and Neurosciences, VU University Medical Center, Amsterdam NL-1007MB, The Netherlands
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam NL-1098XH, The Netherlands
| | - Amy L Griffin
- Department of Psychological and Brain Sciences, University of Delaware, Newark, Delaware 19716, USA
| | - Hiroshi T Ito
- Max Planck Institute for Brain Research, 60438, Frankfurt am Main, Germany
| | - Matthew L Shapiro
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York 12208, USA
| | - Menno P Witter
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU Norwegian University of Science and Technology, Trondheim NO-7491, Norway
| | - Robert P Vertes
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, Florida 33431, USA
| | - Timothy A Allen
- Cognitive Neuroscience Program, Department of Psychology, Florida International University, Miami, Florida 33199, USA
- Department of Environmental Health Sciences, Florida International University, Miami, Florida 33199, USA
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21
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Mathiasen ML, Amin E, Nelson AJD, Dillingham CM, O'Mara SM, Aggleton JP. Separate cortical and hippocampal cell populations target the rat nucleus reuniens and mammillary bodies. Eur J Neurosci 2019; 49:1649-1672. [PMID: 30633830 PMCID: PMC6618334 DOI: 10.1111/ejn.14341] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 11/28/2018] [Accepted: 12/04/2018] [Indexed: 01/07/2023]
Abstract
Nucleus reuniens receives dense projections from both the hippocampus and the frontal cortices. Reflecting these connections, this nucleus is thought to enable executive functions, including those involving spatial learning. The mammillary bodies, which also support spatial learning, again receive dense hippocampal inputs, as well as lighter projections from medial frontal areas. The present study, therefore, compared the sources of these inputs to nucleus reuniens and the mammillary bodies. Retrograde tracer injections in rats showed how these two diencephalic sites receive projections from separate cell populations, often from adjacent layers in the same cortical areas. In the subiculum, which projects strongly to both sites, the mammillary body inputs originate from a homogenous pyramidal cell population in more superficial levels, while the cells that target nucleus reuniens most often originate from cells positioned at a deeper level. In these deeper levels, a more morphologically diverse set of subiculum cells contributes to the thalamic projection, especially at septal levels. While both diencephalic sites also receive medial frontal inputs, those to nucleus reuniens are especially dense. The densest inputs to the mammillary bodies appear to arise from the dorsal peduncular cortex, where the cells are mostly separate from deeper neurons that project to nucleus reuniens. Again, in those other cortical regions that innervate both nucleus reuniens and the mammillary bodies, there was no evidence of collateral projections. The findings support the notion that these diencephalic nuclei represent components of distinct, but complementary, systems that support different aspects of cognition.
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Affiliation(s)
| | - Eman Amin
- School of PsychologyCardiff UniversityWalesUK
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22
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Klein MM, Cholvin T, Cosquer B, Salvadori A, Le Mero J, Kourouma L, Boutillier AL, Pereira de Vasconcelos A, Cassel JC. Ventral midline thalamus lesion prevents persistence of new (learning-triggered) hippocampal spines, delayed neocortical spinogenesis, and spatial memory durability. Brain Struct Funct 2019; 224:1659-1676. [PMID: 30927056 DOI: 10.1007/s00429-019-01865-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 03/20/2019] [Indexed: 01/09/2023]
Abstract
The ventral midline thalamus contributes to hippocampo-cortical interactions supporting systems-level consolidation of memories. Recent hippocampus-dependent memories rely on hippocampal connectivity remodeling. Remote memories are underpinned by neocortical connectivity remodeling. After a ventral midline thalamus lesion, recent spatial memories are formed normally but do not last. Why these memories do not endure after the lesion is unknown. We hypothesized that a lesion could interfere with hippocampal and/or neocortical connectivity remodeling. To test this hypothesis, in a first experiment male rats were subjected to lesion of the reuniens and rhomboid (ReRh) nuclei, trained in a water maze, and tested in a probe trial 5 or 25 days post-acquisition. Dendritic spines were counted in the dorsal hippocampus and medial prefrontal cortex. Spatial learning resulted in a significant increase of mushroom spines in region CA1. This modification persisted between 5 and 25 days post-acquisition in Sham rats, not in rats with ReRh lesion. Furthermore, 25 days after acquisition, the number of mushroom spines in the anterior cingulate cortex (ACC) had undergone a dramatic increase in Sham rats; ReRh lesion prevented this gain. In a second experiment, the increase of c-Fos expression in CA1 accompanying memory retrieval was not affected by the lesion, be it for recent or remote memory. However, in the ACC, the lesion had reduced the retrieval-triggered c-Fos expression observed 25 days post-acquisition. These observations suggest that a ReRh lesion might disrupt spatial remote memory formation by preventing persistence of early remodeled hippocampal connectivity, and spinogenesis in the ACC.
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Affiliation(s)
- Marie Muguet Klein
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), UMR 7364, Université de Strasbourg-CNRS, 12 rue Goethe, 67000, Strasbourg, France.,CNRS, LNCA UMR 7364, 67000, Strasbourg, France
| | - Thibault Cholvin
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), UMR 7364, Université de Strasbourg-CNRS, 12 rue Goethe, 67000, Strasbourg, France.,CNRS, LNCA UMR 7364, 67000, Strasbourg, France
| | - Brigitte Cosquer
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), UMR 7364, Université de Strasbourg-CNRS, 12 rue Goethe, 67000, Strasbourg, France.,CNRS, LNCA UMR 7364, 67000, Strasbourg, France
| | - Aurélie Salvadori
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), UMR 7364, Université de Strasbourg-CNRS, 12 rue Goethe, 67000, Strasbourg, France.,CNRS, LNCA UMR 7364, 67000, Strasbourg, France
| | - Julia Le Mero
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), UMR 7364, Université de Strasbourg-CNRS, 12 rue Goethe, 67000, Strasbourg, France.,CNRS, LNCA UMR 7364, 67000, Strasbourg, France
| | - Lola Kourouma
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), UMR 7364, Université de Strasbourg-CNRS, 12 rue Goethe, 67000, Strasbourg, France.,CNRS, LNCA UMR 7364, 67000, Strasbourg, France
| | - Anne-Laurence Boutillier
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), UMR 7364, Université de Strasbourg-CNRS, 12 rue Goethe, 67000, Strasbourg, France.,CNRS, LNCA UMR 7364, 67000, Strasbourg, France
| | - Anne Pereira de Vasconcelos
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), UMR 7364, Université de Strasbourg-CNRS, 12 rue Goethe, 67000, Strasbourg, France.,CNRS, LNCA UMR 7364, 67000, Strasbourg, France
| | - Jean-Christophe Cassel
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), UMR 7364, Université de Strasbourg-CNRS, 12 rue Goethe, 67000, Strasbourg, France. .,CNRS, LNCA UMR 7364, 67000, Strasbourg, France.
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23
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Parnaudeau S, Bolkan SS, Kellendonk C. The Mediodorsal Thalamus: An Essential Partner of the Prefrontal Cortex for Cognition. Biol Psychiatry 2018; 83:648-656. [PMID: 29275841 PMCID: PMC5862748 DOI: 10.1016/j.biopsych.2017.11.008] [Citation(s) in RCA: 162] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 11/06/2017] [Accepted: 11/06/2017] [Indexed: 01/17/2023]
Abstract
Deficits in cognition are a core feature of many psychiatric conditions, including schizophrenia, where the severity of such deficits is a strong predictor of long-term outcome. Impairment in cognitive domains such as working memory and behavioral flexibility has typically been associated with prefrontal cortex (PFC) dysfunction. However, there is increasing evidence that the PFC cannot be dissociated from its main thalamic counterpart, the mediodorsal thalamus (MD). Since the causal relationships between MD-PFC abnormalities and cognitive impairment, as well as the neuronal mechanisms underlying them, are difficult to address in humans, animal models have been employed for mechanistic insight. In this review, we discuss anatomical, behavioral, and electrophysiological findings from animal studies that provide a new understanding on how MD-PFC circuits support higher-order cognitive function. We argue that the MD may be required for amplifying and sustaining cortical representations under different behavioral conditions. These findings advance a new framework for the broader involvement of distributed thalamo-frontal circuits in cognition and point to the MD as a potential therapeutic target for improving cognitive deficits in schizophrenia and other disorders.
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Affiliation(s)
- Sébastien Parnaudeau
- Sorbonne Universités, Université Pierre et Marie Curie Paris 06, Institut de Biologie Paris Seine UM119, Neuroscience Paris Seine, Centre National de la Recherche Scientifique UMR8246, Institut National de la Santé et de la Recherche Médicale U1130, Paris, France
| | - Scott S Bolkan
- Graduate Program in Neurobiology and Behavior, Columbia University, College of Physicians and Surgeons, New York, New York
| | - Christoph Kellendonk
- Departments of Pharmacology and Psychiatry, Columbia University, College of Physicians and Surgeons, New York, New York; Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, New York.
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24
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Pinnell RC, Pereira de Vasconcelos A, Cassel JC, Hofmann UG. A Miniaturized, Programmable Deep-Brain Stimulator for Group-Housing and Water Maze Use. Front Neurosci 2018; 12:231. [PMID: 29706862 PMCID: PMC5906879 DOI: 10.3389/fnins.2018.00231] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 03/23/2018] [Indexed: 12/20/2022] Open
Abstract
Pre-clinical deep-brain stimulation (DBS) research has observed a growing interest in the use of portable stimulation devices that can be carried by animals. Not only can such devices overcome many issues inherent with a cable tether, such as twisting or snagging, they can also be utilized in a greater variety of arenas, including enclosed or large mazes. However, these devices are not inherently designed for water-maze environments, and their use has been restricted to individually-housed rats in order to avoid damage from various social activities such as grooming, playing, or fighting. By taking advantage of 3D-printing techniques, this study demonstrates an ultra-small portable stimulator with an environmentally-protective device housing, that is suitable for both social-housing and water-maze environments. The miniature device offers 2 channels of charge-balanced biphasic pulses with a high compliance voltage (12 V), a magnetic switch, and a diverse range of programmable stimulus parameters and pulse modes. The device's capabilities have been verified in both chronic pair-housing and water-maze experiments that asses the effects of nucleus reuniens DBS. Theta-burst stimulation delivered during a reference-memory water-maze task (but not before) had induced performance deficits during both the acquisition and probe trials of a reference memory task. The results highlight a successful application of 3D-printing for expanding on the range of measurement modalities capable in DBS research.
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Affiliation(s)
- Richard C Pinnell
- Laboratoire de Neurosciences Cognitives et Adaptatives, Faculté de Psychologie de Strasbourg, Université de Strasbourg, Strasbourg, France.,Section of Neuroelectronic Systems, Neurosurgery, Medical Centre, University of Freiburg, Freiburg im Breisgau, Germany.,Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany.,Freiburg Institute for Advanced Studies, University of Freiburg, Freiburg im Breisgau, Germany.,University of Strasbourg Institute for Advanced Study, University of Strasbourg, Strasbourg, France
| | - Anne Pereira de Vasconcelos
- Laboratoire de Neurosciences Cognitives et Adaptatives, Faculté de Psychologie de Strasbourg, Université de Strasbourg, Strasbourg, France.,LNCA, UMR 7364, Centre National de la Recherche Scientifique, Strasbourg, France
| | - Jean C Cassel
- Laboratoire de Neurosciences Cognitives et Adaptatives, Faculté de Psychologie de Strasbourg, Université de Strasbourg, Strasbourg, France.,Freiburg Institute for Advanced Studies, University of Freiburg, Freiburg im Breisgau, Germany.,University of Strasbourg Institute for Advanced Study, University of Strasbourg, Strasbourg, France.,LNCA, UMR 7364, Centre National de la Recherche Scientifique, Strasbourg, France
| | - Ulrich G Hofmann
- Section of Neuroelectronic Systems, Neurosurgery, Medical Centre, University of Freiburg, Freiburg im Breisgau, Germany.,Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany.,Freiburg Institute for Advanced Studies, University of Freiburg, Freiburg im Breisgau, Germany.,University of Strasbourg Institute for Advanced Study, University of Strasbourg, Strasbourg, France
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25
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The Nucleus Reuniens Controls Long-Range Hippocampo-Prefrontal Gamma Synchronization during Slow Oscillations. J Neurosci 2018; 38:3026-3038. [PMID: 29459369 DOI: 10.1523/jneurosci.3058-17.2018] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 01/12/2018] [Accepted: 01/17/2018] [Indexed: 12/30/2022] Open
Abstract
Gamma oscillations are involved in long-range coupling of distant regions that support various cognitive operations. Here we show in adult male rats that synchronized bursts of gamma oscillations bind the hippocampus (HPC) and prefrontal cortex (mPFC) during slow oscillations and slow-wave sleep, a brain state that is central for consolidation of memory traces. These gamma bursts entrained the firing of the local HPC and mPFC neuronal populations. Neurons of the nucleus reuniens (NR), which is a structural and functional hub between HPC and mPFC, demonstrated a specific increase in their firing before gamma burst onset, suggesting their involvement in HPC-mPFC binding. Chemical inactivation of NR disrupted the temporal pattern of gamma bursts and their synchronization, as well as mPFC neuronal firing. We propose that the NR drives long-range hippocampo-prefrontal coupling via gamma bursts providing temporal windows for information exchange between the HPC and mPFC during slow-wave sleep.SIGNIFICANCE STATEMENT Long-range coupling between hippocampus (HPC) and prefrontal cortex (mPFC) is believed to support numerous cognitive functions, including memory consolidation occurring during sleep. Gamma-band synchronization is a fundamental process in many neuronal operations and is instrumental in long-range coupling. Recent evidence highlights the role of nucleus reuniens (NR) in consolidation; however, how it influences hippocampo-prefrontal coupling is unknown. In this study, we show that HPC and mPFC are synchronized by gamma bursts during slow oscillations in anesthesia and natural sleep. By manipulating and recording the NR-HPC-mPFC network, we provide evidence that the NR actively promotes this long-range gamma coupling. This coupling provides the hippocampo-prefrontal circuit with a novel mechanism to exchange information during slow-wave sleep.
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26
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A Critical Role for the Nucleus Reuniens in Long-Term, But Not Short-Term Associative Recognition Memory Formation. J Neurosci 2018; 38:3208-3217. [PMID: 29449430 DOI: 10.1523/jneurosci.1802-17.2017] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 10/30/2017] [Accepted: 11/29/2017] [Indexed: 11/21/2022] Open
Abstract
Recognition memory for single items requires the perirhinal cortex (PRH), whereas recognition of an item and its associated location requires a functional interaction among the PRH, hippocampus (HPC), and medial prefrontal cortex (mPFC). Although the precise mechanisms through which these interactions are effected are unknown, the nucleus reuniens (NRe) has bidirectional connections with each regions and thus may play a role in recognition memory. Here we investigated, in male rats, whether specific manipulations of NRe function affected performance of recognition memory for single items, object location, or object-in-place associations. Permanent lesions in the NRe significantly impaired long-term, but not short-term, object-in-place associative recognition memory, whereas single item recognition memory and object location memory were unaffected. Temporary inactivation of the NRe during distinct phases of the object-in-place task revealed its importance in both the encoding and retrieval stages of long-term associative recognition memory. Infusions of specific receptor antagonists showed that encoding was dependent on muscarinic and nicotinic cholinergic neurotransmission, whereas NMDA receptor neurotransmission was not required. Finally, we found that long-term object-in-place memory required protein synthesis within the NRe. These data reveal a specific role for the NRe in long-term associative recognition memory through its interactions with the HPC and mPFC, but not the PRH. The delay-dependent involvement of the NRe suggests that it is not a simple relay station between brain regions, but, rather, during high mnemonic demand, facilitates interactions between the mPFC and HPC, a process that requires both cholinergic neurotransmission and protein synthesis.SIGNIFICANCE STATEMENT Recognizing an object and its associated location, which is fundamental to our everyday memory, requires specific hippocampal-cortical interactions, potentially facilitated by the nucleus reuniens (NRe) of the thalamus. However, the role of the NRe itself in associative recognition memory is unknown. Here, we reveal the crucial role of the NRe in encoding and retrieval of long-term object-in-place memory, but not for remembrance of an individual object or individual location and such involvement is cholinergic receptor and protein synthesis dependent. This is the first demonstration that the NRe is a key node within an associative recognition memory network and is not just a simple relay for information within the network. Rather, we argue, the NRe actively modulates information processing during long-term associative memory formation.
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27
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Mei H, Logothetis NK, Eschenko O. The activity of thalamic nucleus reuniens is critical for memory retrieval, but not essential for the early phase of "off-line" consolidation. ACTA ACUST UNITED AC 2018; 25:129-137. [PMID: 29449457 PMCID: PMC5817284 DOI: 10.1101/lm.047134.117] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2017] [Accepted: 12/19/2017] [Indexed: 11/25/2022]
Abstract
Spatial navigation depends on the hippocampal function, but also requires bidirectional interactions between the hippocampus (HPC) and the prefrontal cortex (PFC). The cross-regional communication is typically regulated by critical nodes of a distributed brain network. The thalamic nucleus reuniens (RE) is reciprocally connected to both HPC and PFC and may coordinate the information flow within the HPC-PFC pathway. Here we examined if RE activity contributes to the spatial memory consolidation. Rats were trained to find reward following a complex trajectory on a crossword-like maze. Immediately after each of the five daily learning sessions the RE was reversibly inactivated by local injection of muscimol. The post-training RE inactivation affected neither the spatial task acquisition nor the memory retention, which was tested after a 20-d "forgetting" period. In contrast, the RE inactivation in well-trained rats prior to the maze exposure impaired the task performance without affecting locomotion or appetitive motivation. Our results support the role of the RE in memory retrieval and/or "online" processing of spatial information, but do not provide evidence for its engagement in "off-line" processing, at least within a time window immediately following learning experience.
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Affiliation(s)
- Hao Mei
- Max Planck Institute for Biological Cybernetics, Tübingen 72076, Germany
| | - Nikos K Logothetis
- Max Planck Institute for Biological Cybernetics, Tübingen 72076, Germany.,Centre for Imaging Sciences, Biomedical Imaging Institute, The University of Manchester, Manchester M13 9PT, United Kingdom
| | - Oxana Eschenko
- Max Planck Institute for Biological Cybernetics, Tübingen 72076, Germany
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28
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Viena TD, Linley SB, Vertes RP. Inactivation of nucleus reuniens impairs spatial working memory and behavioral flexibility in the rat. Hippocampus 2018; 28:297-311. [PMID: 29357198 DOI: 10.1002/hipo.22831] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 12/19/2017] [Accepted: 01/18/2018] [Indexed: 02/03/2023]
Abstract
The hippocampal formation (HF) and medial prefrontal cortex (mPFC) play critical roles in spatial working memory (SWM). The nucleus reuniens (RE) of the ventral midline thalamus is an important anatomical link between the HF and mPFC, and as such is crucially involved in SWM functions that recruit both structures. Little is known, however, regarding the role of RE in other behaviors mediated by this circuit. In the present study, we examined the role of RE in spatial working memory and executive functioning following reversible inactivation of RE with either muscimol or procaine. Rats were implanted with an indwelling cannula targeting RE and trained in a delayed nonmatch to sample spatial alternation T-maze task. For the task, sample and choice runs were separated by moderate or long delays (30, 60, and 120 s). Following asymptotic performance, rats were tested following infusions of drug or vehicle. Muscimol infused into RE impaired SWM at all delays, whereby procaine only impaired performance at the longest delays. Furthermore, RE inactivation with muscimol produced a failure in win-shift strategy as well as severe spatial perseveration, whereby rats persistently made re-entries into incorrect arms during correction trials, despite the absence of reward. This demonstrated marked changes in behavioral flexibility and response strategy. These results strengthen the role of nucleus reuniens as a pivotal link between hippocampus and prefrontal cortex in cognitive and executive functions and suggest that nucleus reuniens may be a potential target in the treatment of CNS disorders such as schizophrenia, attention deficit hyperactivity disorder, addiction, and obsessive-compulsive disorder, whose symptoms are defined by hippocampal-prefrontal dysfunctions.
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Affiliation(s)
- Tatiana D Viena
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, Florida 33431
| | - Stephanie B Linley
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, Florida 33431.,Department of Psychology, Florida Atlantic University, Boca Raton, Florida 33431
| | - Robert P Vertes
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, Florida 33431
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29
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Cholvin T, Hok V, Giorgi L, Chaillan FA, Poucet B. Ventral Midline Thalamus Is Necessary for Hippocampal Place Field Stability and Cell Firing Modulation. J Neurosci 2018; 38:158-172. [PMID: 29133436 PMCID: PMC6705806 DOI: 10.1523/jneurosci.2039-17.2017] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 10/12/2017] [Accepted: 11/07/2017] [Indexed: 12/21/2022] Open
Abstract
The reuniens (Re) and rhomboid (Rh) nuclei of the ventral midline thalamus are reciprocally connected with the hippocampus (Hip) and the medial prefrontal cortex (mPFC). Growing evidence suggests that these nuclei might play a crucial role in cognitive processes requiring Hip-mPFC interactions, including spatial navigation. Here, we tested the effect of ReRh lesions on the firing properties and spatial activity of dorsal hippocampal CA1 place cells as male rats explored a familiar or a novel environment. We found no change in the spatial characteristics of CA1 place cells in the familiar environment following ReRh lesions. Contrariwise, spatial coherence was decreased during the first session in a novel environment. We then investigated field stability of place cells recorded across 5 d both in the familiar and in a novel environment presented in a predefined sequence. While the remapping capacity of the place cells was not affected by the lesion, our results clearly demonstrated a disruption of the CA1 cellular representation of both environments in ReRh rats. More specifically, we found ReRh lesions to produce (1) a pronounced and long-lasting decrease of place field stability and (2) a strong alteration of overdispersion (i.e., firing variability). Thus, in ReRh rats, exploration of a novel environment appears to interfere with the representation of the familiar one, leading to decreased field stability in both environments. The present study shows the involvement of ReRh nuclei in the long-term spatial stability of CA1 place fields.SIGNIFICANCE STATEMENT Growing evidence suggest that the ventral midline thalamic nuclei (reuniens and rhomboid) might play a substantial role in various cognitive tasks including spatial memory. In the present article, we show that the lesions of these nuclei impair the spatial representations encoded by CA1 place cells of both familiar and novel environments. First, reduced variability of place cell firing appears to indicate an impairment of attentional processes. Second, impaired stability of place cell representations could explain the long-term memory deficits observed in previous behavioral studies.
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Affiliation(s)
- Thibault Cholvin
- Laboratoire de Neurosciences Cognitives and
- Federation 3C, CNRS, Aix Marseille University, 13331 Marseille, France
| | - Vincent Hok
- Laboratoire de Neurosciences Cognitives and
- Federation 3C, CNRS, Aix Marseille University, 13331 Marseille, France
| | - Lisa Giorgi
- Laboratoire de Neurosciences Cognitives and
- Federation 3C, CNRS, Aix Marseille University, 13331 Marseille, France
| | - Franck A Chaillan
- Laboratoire de Neurosciences Cognitives and
- Federation 3C, CNRS, Aix Marseille University, 13331 Marseille, France
| | - Bruno Poucet
- Laboratoire de Neurosciences Cognitives and
- Federation 3C, CNRS, Aix Marseille University, 13331 Marseille, France
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30
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Kafetzopoulos V, Kokras N, Sotiropoulos I, Oliveira JF, Leite-Almeida H, Vasalou A, Sardinha VM, Papadopoulou-Daifoti Z, Almeida OFX, Antoniou K, Sousa N, Dalla C. The nucleus reuniens: a key node in the neurocircuitry of stress and depression. Mol Psychiatry 2018; 23:579-586. [PMID: 28397837 PMCID: PMC5822458 DOI: 10.1038/mp.2017.55] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 02/14/2017] [Accepted: 02/16/2017] [Indexed: 02/08/2023]
Abstract
The hippocampus and prefrontal cortex (PFC) are connected in a reciprocal manner: whereas the hippocampus projects directly to the PFC, a polysynaptic pathway that passes through the nucleus reuniens (RE) of the thalamus relays inputs from the PFC to the hippocampus. The present study demonstrates that lesioning and/or inactivation of the RE reduces coherence in the PFC-hippocampal pathway, provokes an antidepressant-like behavioral response in the forced swim test and prevents, but does not ameliorate, anhedonia in the chronic mild stress (CMS) model of depression. Additionally, RE lesioning before CMS abrogates the well-known neuromorphological and endocrine correlates of CMS. In summary, this work highlights the importance of the reciprocal connectivity between the hippocampus and PFC in the establishment of stress-induced brain pathology and suggests a role for the RE in promoting resilience to depressive illness.
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Affiliation(s)
- V Kafetzopoulos
- Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - N Kokras
- Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Athens, Greece,First Department of Psychiatry, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - I Sotiropoulos
- Life and Health Sciences Research Institute (ICVS), University of Minho, Braga, Portugal,ICVS/3B’s, PT Government Associate Laboratory, Braga, Portugal
| | - J F Oliveira
- Life and Health Sciences Research Institute (ICVS), University of Minho, Braga, Portugal,ICVS/3B’s, PT Government Associate Laboratory, Braga, Portugal
| | - H Leite-Almeida
- Life and Health Sciences Research Institute (ICVS), University of Minho, Braga, Portugal,ICVS/3B’s, PT Government Associate Laboratory, Braga, Portugal
| | - A Vasalou
- Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - V M Sardinha
- Life and Health Sciences Research Institute (ICVS), University of Minho, Braga, Portugal,ICVS/3B’s, PT Government Associate Laboratory, Braga, Portugal
| | - Z Papadopoulou-Daifoti
- Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - O F X Almeida
- NeuroAdaptations Group, Max Planck Institute of Psychiatry, Munich, Germany
| | - K Antoniou
- Department of Pharmacology, University of Ioannina, Ioannina, Greece
| | - N Sousa
- Life and Health Sciences Research Institute (ICVS), University of Minho, Braga, Portugal,ICVS/3B’s, PT Government Associate Laboratory, Braga, Portugal
| | - C Dalla
- Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Athens, Greece,Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Mikras Asias 75, Athens 11527, Greece. E-mail:
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31
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Corticothalamic network dysfunction and Alzheimer's disease. Brain Res 2017; 1702:38-45. [PMID: 28919464 DOI: 10.1016/j.brainres.2017.09.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 09/11/2017] [Indexed: 12/11/2022]
Abstract
Alzheimer's disease (AD) is a devastating neurodegenerative disease that is characterized by progressive cognitive decline and a prominent loss of hippocampal-dependent memory. Therefore, much focus has been placed on understanding the function and dysfunction of the hippocampus in AD. However, AD is also accompanied by a number of other debilitating cognitive and behavioral alterations including deficits in attention, cognitive processing, and sleep maintenance. The underlying mechanisms that give rise to impairments in such diverse behavioral domains are unknown, and identifying them would shed insight into the multifactorial nature of AD as well as reveal potential new therapeutic targets to improve overall function in AD. We present here several lines of evidence that suggest that dysregulation of the corticothalamic network may be a common denominator that contributes to the diverse cognitive and behavioral alterations in AD. First, we will review the mechanisms by which this network regulates processes that include attention, cognitive processing, learning and memory, and sleep maintenance. Then we will review how these behavioral and cognitive domains are altered in AD. We will also discuss how dysregulation of tightly regulated activity in the corticothalamic network can give rise to non-convulsive seizures and other forms of epileptiform activity that have also been documented in both AD patients and transgenic mouse models of AD. In summary, the corticothalamic network has the potential to be a master regulator of diverse cognitive and behavioral domains that are affected in AD.
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32
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Dolleman-van der Weel MJ, Lopes da Silva FH, Witter MP. Interaction of nucleus reuniens and entorhinal cortex projections in hippocampal field CA1 of the rat. Brain Struct Funct 2016; 222:2421-2438. [PMID: 28008472 DOI: 10.1007/s00429-016-1350-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 12/14/2016] [Indexed: 02/03/2023]
Abstract
The nucleus reuniens (RE) and entorhinal cortex (EC) provide monosynaptic excitatory inputs to the apical dendrites of pyramidal cells and to interneurons with dendrites in stratum lacunosum moleculare (LM) of hippocampal field CA1. However, whether the RE and EC inputs interact at the cellular level is unknown. In this electrophysiological in vivo study, low-frequency stimulation was used to selectively activate each projection at its origin; field excitatory postsynaptic potentials (fEPSPs) were recorded in CA1. We applied (1) paired pulses to RE or EC, (2) combined paired pulses to RE and EC, and (3) simultaneously paired pulses to RE/EC. The main findings are that: (a) stimulation of either RE- or EC-evoked subthreshold fEPSPs, displaying paired pulse facilitation (PPF), (b) subthreshold fEPSPs evoked by combined stimulation did not display heterosynaptic PPF, and (c) simultaneous stimulation of RE/EC resulted in enhanced subthreshold fEPSPs in proximal LM displaying a nonlinear interaction. CSD analyses of RE/EC-evoked depth profiles revealed a nonlinear enlargement of the 'LM sink-radiatum source' configuration and the appearance of an additional small sink-source pair close to stratum pyramidale, likely reflecting (peri)somatic inhibition. The nonlinear interaction between both inputs indicates that RE and EC axons form synapses, at least partly, onto the same dendritic compartments of CA1 pyramidal cells. We propose that low-frequency activation of the RE-CA1 input facilitates the entorhinal-hippocampal dialogue, and may synchronize the neocortical-hippocampal slow oscillation which is relevant for hippocampal-dependent memory consolidation.
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Affiliation(s)
- M J Dolleman-van der Weel
- Department of Anatomy and Neurosciences, VU University Medical Center, 1081 BT, Amsterdam, The Netherlands
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, 1098 XH, Amsterdam, The Netherlands
| | - F H Lopes da Silva
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, 1098 XH, Amsterdam, The Netherlands
- Department of Bioengineering, Instituto Superior Técnico, Lisbon Technical University, 1049-001, Lisbon, Portugal
| | - M P Witter
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, MTFS, Norwegian University of Science and Technology (NTNU), Postboks 8905, 7491, Trondheim, Norway.
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33
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Linley SB, Gallo MM, Vertes RP. Lesions of the ventral midline thalamus produce deficits in reversal learning and attention on an odor texture set shifting task. Brain Res 2016; 1649:110-122. [PMID: 27544424 PMCID: PMC5796786 DOI: 10.1016/j.brainres.2016.08.022] [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: 05/11/2016] [Revised: 08/15/2016] [Accepted: 08/17/2016] [Indexed: 12/13/2022]
Abstract
The nucleus reuniens (RE) of the ventral midline thalamus is strongly reciprocally connected with the hippocampus (HF) and the medial prefrontal cortex (mPFC) and has been shown to mediate the transfer of information between these structures. It has become increasingly well established that RE serves a critical role in mnemonic tasks requiring the interaction of the HF and mPFC, but essentially not tasks relying solely on the HF. Very few studies have addressed the independent actions of RE on prefrontal executive functioning. The present report examined the effects of lesions of the ventral midline thalamus, including RE and the dorsally adjacent rhomboid nucleus (RH) in rats on attention and behavioral flexibility using the attentional set shifting task (AST). The task uses odor and tactile stimuli to test for attentional set formation, attentional set shifting, behavioral flexibility and reversal learning. By comparison with sham controls, lesioned rats were significantly impaired on reversal learning and intradimensional (ID) set shifting. Specifically, RE/RH lesioned rats were impaired on the first reversal stage of the task which required a change in response strategy to select a previously non-rewarded stimulus for reward. RE/RH lesioned rats also exhibited deficits in the ability to transfer or generalize rules of the task which requires making the same modality-based choices (e.g., odor vs. tactile) to different sets of stimuli in the ID stage of the task. These results demonstrate that in addition to its role in tasks dependent on HF-mPFC interactions, nucleus reuniens is also critically involved cognitive/executive functions associated with the medial prefrontal cortex. As such, the deficits in the AST task produced by RE/RH lesions suggest the ventral midline thalamus directly contributes to flexible goal directed behavior.
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Affiliation(s)
- Stephanie B Linley
- Department of Psychology, Florida Atlantic University, Boca Raton, FL 33431, United States; Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL 33431, United States
| | - Michelle M Gallo
- Department of Psychology, Florida Atlantic University, Boca Raton, FL 33431, United States
| | - Robert P Vertes
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL 33431, United States.
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Prasad JA, Abela AR, Chudasama Y. Midline thalamic reuniens lesions improve executive behaviors. Neuroscience 2016; 345:77-88. [PMID: 26868974 DOI: 10.1016/j.neuroscience.2016.01.071] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 01/25/2016] [Accepted: 01/27/2016] [Indexed: 12/29/2022]
Abstract
The role of the thalamus in complex cognitive behavior is a topic of increasing interest. Here we demonstrate that lesions of the nucleus reuniens (NRe), a midline thalamic nucleus interconnected with both hippocampal and prefrontal circuitry, lead to enhancement of executive behaviors typically associated with the prefrontal cortex. Rats were tested on four behavioral tasks: (1) the combined attention-memory (CAM) task, which simultaneously assessed attention to a visual target and memory for that target over a variable delay; (2) spatial memory using a radial arm maze, (3) discrimination and reversal learning using a touchscreen operant platform, and (4) decision-making with delayed outcomes. Following NRe lesions, the animals became more efficient in their performance, responding with shorter reaction times but also less impulsively than controls. This change, combined with a decrease in perseverative responses, led to focused attention in the CAM task and accelerated learning in the visual discrimination task. There were no observed changes in tasks involving either spatial memory or value-based decision making. These data complement ongoing efforts to understand the role of midline thalamic structures in human cognition, including the development of thalamic stimulation as a therapeutic strategy for acquired cognitive disabilities (Schiff, 2008; Mair et al., 2011), and point to the NRe as a potential target for clinical intervention.
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Affiliation(s)
- J A Prasad
- Department of Psychology, McGill University, Montreal, QC, H3A 1B1, Canada
| | - A R Abela
- Department of Psychology, McGill University, Montreal, QC, H3A 1B1, Canada
| | - Y Chudasama
- Department of Psychology, McGill University, Montreal, QC, H3A 1B1, Canada.
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Basu J, Siegelbaum SA. The Corticohippocampal Circuit, Synaptic Plasticity, and Memory. Cold Spring Harb Perspect Biol 2015; 7:7/11/a021733. [PMID: 26525152 DOI: 10.1101/cshperspect.a021733] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Synaptic plasticity serves as a cellular substrate for information storage in the central nervous system. The entorhinal cortex (EC) and hippocampus are interconnected brain areas supporting basic cognitive functions important for the formation and retrieval of declarative memories. Here, we discuss how information flow in the EC-hippocampal loop is organized through circuit design. We highlight recently identified corticohippocampal and intrahippocampal connections and how these long-range and local microcircuits contribute to learning. This review also describes various forms of activity-dependent mechanisms that change the strength of corticohippocampal synaptic transmission. A key point to emerge from these studies is that patterned activity and interaction of coincident inputs gives rise to associational plasticity and long-term regulation of information flow. Finally, we offer insights about how learning-related synaptic plasticity within the corticohippocampal circuit during sensory experiences may enable adaptive behaviors for encoding spatial, episodic, social, and contextual memories.
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Affiliation(s)
- Jayeeta Basu
- Department of Neuroscience and Physiology, NYU Neuroscience Institute, New York University School of Medicine, New York, New York 10016
| | - Steven A Siegelbaum
- Kavli Institute for Brain Science, Columbia University, New York, New York 10032 Department of Neuroscience, Columbia University, New York, New York 10032 Department of Pharmacology, Columbia University, New York, New York 10032
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Jankowski MM, Passecker J, Islam MN, Vann S, Erichsen JT, Aggleton JP, O'Mara SM. Evidence for spatially-responsive neurons in the rostral thalamus. Front Behav Neurosci 2015; 9:256. [PMID: 26528150 PMCID: PMC4602090 DOI: 10.3389/fnbeh.2015.00256] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 09/07/2015] [Indexed: 12/30/2022] Open
Abstract
Damage involving the anterior thalamic and adjacent rostral thalamic nuclei may result in a severe anterograde amnesia, similar to the amnesia resulting from damage to the hippocampal formation. Little is known, however, about the information represented in these nuclei. To redress this deficit, we recorded units in three rostral thalamic nuclei in freely-moving rats [the parataenial nucleus (PT), the anteromedial nucleus (AM) and nucleus reuniens NRe]. We found units in these nuclei possessing previously unsuspected spatial properties. The various cell types show clear similarities to place cells, head direction cells, and perimeter/border cells described in hippocampal and parahippocampal regions. Based on their connectivity, it had been predicted that the anterior thalamic nuclei process information with high spatial and temporal resolution while the midline nuclei have more diffuse roles in attention and arousal. Our current findings strongly support the first prediction but directly challenge or substantially moderate the second prediction. The rostral thalamic spatial cells described here may reflect direct hippocampal/parahippocampal inputs, a striking finding of itself, given the relative lack of place cells in other sites receiving direct hippocampal formation inputs. Alternatively, they may provide elemental thalamic spatial inputs to assist hippocampal spatial computations. Finally, they could represent a parallel spatial system in the brain.
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Affiliation(s)
| | | | - Md Nurul Islam
- Institute of Neuroscience, Trinity College Dublin Dublin, Ireland
| | | | | | | | - Shane M O'Mara
- Institute of Neuroscience, Trinity College Dublin Dublin, Ireland
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Wolff M, Faugère A, Desfosses É, Coutureau É, Marchand AR. Mediodorsal but not anterior thalamic nuclei lesions impair acquisition of a conditional discrimination task. Neurobiol Learn Mem 2015; 125:80-4. [PMID: 26254715 DOI: 10.1016/j.nlm.2015.07.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 07/22/2015] [Accepted: 07/29/2015] [Indexed: 12/13/2022]
Abstract
The limbic thalamus is a heterogeneous structure with distinctive cortical connectivity. A recent review suggests that the mediodorsal thalamic nucleus (MD), unlike the anterior thalamic nuclei (ATN), may be involved in selecting relevant information in tasks relying on executive functions. We compared the effects of excitotoxic lesions of the MD or the ATN on the acquisition of a simple conditional discrimination in rats. When required to choose from two levers according to auditory or visual cues, ATN rats and sham-lesioned rats performed to the same levels and displayed similar acquisition curves. Under the same conditions, MD rats' acquisition of the task was markedly delayed. This group nevertheless attained nearly normal performances after more extensive training. Furthermore, all rats learned reversal of the original discrimination at the same rate. These results highlight functional specialization within the limbic thalamus and support the notion that MD contributes to the identification of relevant dimensions in conditional tasks during the initial stages of acquisition.
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Affiliation(s)
- Mathieu Wolff
- CNRS, INCIA, UMR 5287, 33076 Bordeaux, France; Université de Bordeaux, INCIA, UMR 5287, 33076 Bordeaux, France.
| | - Angélique Faugère
- CNRS, INCIA, UMR 5287, 33076 Bordeaux, France; Université de Bordeaux, INCIA, UMR 5287, 33076 Bordeaux, France
| | - Émilie Desfosses
- CNRS, INCIA, UMR 5287, 33076 Bordeaux, France; Université de Bordeaux, INCIA, UMR 5287, 33076 Bordeaux, France
| | - Étienne Coutureau
- CNRS, INCIA, UMR 5287, 33076 Bordeaux, France; Université de Bordeaux, INCIA, UMR 5287, 33076 Bordeaux, France
| | - Alain R Marchand
- CNRS, INCIA, UMR 5287, 33076 Bordeaux, France; Université de Bordeaux, INCIA, UMR 5287, 33076 Bordeaux, France.
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Vertes RP, Linley SB, Hoover WB. Limbic circuitry of the midline thalamus. Neurosci Biobehav Rev 2015; 54:89-107. [PMID: 25616182 PMCID: PMC4976455 DOI: 10.1016/j.neubiorev.2015.01.014] [Citation(s) in RCA: 241] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 12/19/2014] [Accepted: 01/12/2015] [Indexed: 01/01/2023]
Abstract
The thalamus was subdivided into three major groups: sensorimotor nuclei (or principal/relay nuclei), limbic nuclei and nuclei bridging these two domains. Limbic nuclei of thalamus (or 'limbic thalamus') consist of the anterior nuclei, midline nuclei, medial division of the mediodorsal nucleus (MDm) and central medial nucleus (CM) of the intralaminar complex. The midline nuclei include the paraventricular (PV) and paratenial (PT) nuclei, dorsally, and the reuniens (RE) and rhomboid (RH) nuclei, ventrally. The 'limbic' thalamic nuclei predominantly connect with limbic-related structures and serve a direct role in limbic-associated functions. Regarding the midline nuclei, RE/RH mainly target limbic cortical structures, particularly the hippocampus and the medial prefrontal cortex. Accordingly, RE/RH participate in functions involving interactions of the HF and mPFC. By contrast, PV/PT mainly project to limbic subcortical structures, particularly the amygdala and nucleus accumbens, and hence are critically involved in affective behaviors such as stress/anxiety, feeding behavior, and drug seeking activities. The anatomical/functional characteristics of MDm and CM are very similar to those of the midline nuclei and hence the collection of nuclei extending dorsoventrally along the midline/paramidline of the thalamus constitute the core of the 'limbic thalamus'.
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Affiliation(s)
- Robert P Vertes
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL 33431, United States.
| | - Stephanie B Linley
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL 33431, United States
| | - Walter B Hoover
- Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, United States
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Vertes RP. Major diencephalic inputs to the hippocampus: supramammillary nucleus and nucleus reuniens. Circuitry and function. PROGRESS IN BRAIN RESEARCH 2015; 219:121-44. [PMID: 26072237 DOI: 10.1016/bs.pbr.2015.03.008] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The hippocampus receives two major external inputs from the diencephalon, that is, from the supramammillary nucleus (SUM) and nucleus reuniens (RE) of the midline thalamus. These two afferents systems project to separate, nonoverlapping, regions of the hippocampus. Specifically, the SUM distributes to the dentate gyrus (DG) and to CA2 of the dorsal and ventral hippocampus, whereas RE projects to CA1 of the dorsal and ventral hippocampus and to the subiculum. SUM and RE fibers to the hippocampus participate in common as well as in separate functions. Both systems would appear to amplify signals from other sources to their respective hippocampal targets. SUM amplifies signals from the entorhinal cortex (EC) to DG, whereas RE may amplify them from CA3 (and EC) to CA1 of the hippocampus. This "amplification" may serve to promote the transfer, encoding, and possibly storage of information from EC to DG and from CA3 and EC to CA1. Regarding their unique actions on the hippocampus, the SUM is a vital part of an ascending brainstem to hippocampal system generating the theta rhythm of the hippocampus, whereas RE importantly routes information from the medial prefrontal cortex to the hippocampus to thereby mediate functions involving both structures. In summary, although, to date, SUM and RE afferents to the hippocampus have not been extensively explored, the SUM and RE exert a profound influence on the hippocampus in processes of learning and memory.
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Affiliation(s)
- Robert P Vertes
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL, USA.
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Griffin AL. Role of the thalamic nucleus reuniens in mediating interactions between the hippocampus and medial prefrontal cortex during spatial working memory. Front Syst Neurosci 2015; 9:29. [PMID: 25805977 PMCID: PMC4354269 DOI: 10.3389/fnsys.2015.00029] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 02/17/2015] [Indexed: 11/13/2022] Open
Abstract
Despite decades of research, the neural mechanisms of spatial working memory remain poorly understood. Although the dorsal hippocampus is known to be critical for memory-guided behavior, experimental evidence suggests that spatial working memory depends not only on the hippocampus itself, but also on the circuit comprised of the hippocampus and the medial prefrontal cortex (mPFC). Disruption of hippocampal-mPFC interactions may result in failed transfer of spatial and contextual information processed by the hippocampus to the circuitry in mPFC responsible for decision making and goal-directed behavior. Oscillatory synchrony between the hippocampus and mPFC has been shown to increase in tasks with high spatial working memory demand. However, the mechanisms and circuitry supporting hippocampal-mPFC interactions during these tasks is unknown. The midline thalamic nucleus reuniens (RE) is reciprocally connected to both the hippocampus and the mPFC and has been shown to be critical for a variety of working memory tasks. Therefore, it is likely that hippocampal-mPFC oscillatory synchrony is modulated by RE activity. This article will review the anatomical connections between the hippocampus, mPFC and RE along with the behavioral studies that have investigated the effects of RE disruption on working memory task performance. The article will conclude with suggestions for future directions aimed at identifying the specific role of the RE in regulating functional interactions between the hippocampus and the PFC and investigating the degree to which these interactions contribute to spatial working memory.
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Affiliation(s)
- Amy L Griffin
- Department of Psychological and Brain Sciences, University of Delaware Newark, DE, USA
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41
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Abstract
The main impetus for a mini-symposium on corticothalamic interrelationships was the recent number of studies highlighting the role of the thalamus in aspects of cognition beyond sensory processing. The thalamus contributes to a range of basic cognitive behaviors that include learning and memory, inhibitory control, decision-making, and the control of visual orienting responses. Its functions are deeply intertwined with those of the better studied cortex, although the principles governing its coordination with the cortex remain opaque, particularly in higher-level aspects of cognition. How should the thalamus be viewed in the context of the rest of the brain? Although its role extends well beyond relaying of sensory information from the periphery, the main function of many of its subdivisions does appear to be that of a relay station, transmitting neural signals primarily to the cerebral cortex from a number of brain areas. In cognition, its main contribution may thus be to coordinate signals between diverse regions of the telencephalon, including the neocortex, hippocampus, amygdala, and striatum. This central coordination is further subject to considerable extrinsic control, for example, inhibition from the basal ganglia, zona incerta, and pretectal regions, and chemical modulation from ascending neurotransmitter systems. What follows is a brief review on the role of the thalamus in aspects of cognition and behavior, focusing on a summary of the topics covered in a mini-symposium held at the Society for Neuroscience meeting, 2014.
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Aggleton JP. Looking beyond the hippocampus: old and new neurological targets for understanding memory disorders. Proc Biol Sci 2015; 281:rspb.2014.0565. [PMID: 24850926 PMCID: PMC4046414 DOI: 10.1098/rspb.2014.0565] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Although anterograde amnesia can occur after damage in various brain sites, hippocampal dysfunction is usually seen as the ultimate cause of the failure to learn new episodic information. This assumption is supported by anatomical evidence showing direct hippocampal connections with all other sites implicated in causing anterograde amnesia. Likewise, behavioural and clinical evidence would seem to strengthen the established notion of an episodic memory system emanating from the hippocampus. There is, however, growing evidence that key, interconnected sites may also regulate the hippocampus, reflecting a more balanced, integrated network that enables learning. Recent behavioural evidence strongly suggests that medial diencephalic structures have some mnemonic functions independent of the hippocampus, which can then act upon the hippocampus. Anatomical findings now reveal that nucleus reuniens and the retrosplenial cortex provide parallel, disynaptic routes for prefrontal control of hippocampal activity. There is also growing clinical evidence that retrosplenial cortex dysfunctions contribute to both anterograde amnesia and the earliest stages of Alzheimer's disease, revealing the potential significance of this area for clinical studies. This array of findings underlines the importance of redressing the balance and the value of looking beyond the hippocampus when seeking to explain failures in learning new episodic information.
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Affiliation(s)
- John P Aggleton
- School of Psychology, Cardiff University, Park Place, Cardiff, Wales CF10 3AT, UK
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Cassel JC, Pereira de Vasconcelos A. Importance of the ventral midline thalamus in driving hippocampal functions. PROGRESS IN BRAIN RESEARCH 2015; 219:145-61. [DOI: 10.1016/bs.pbr.2015.03.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Functional heterogeneity of the limbic thalamus: From hippocampal to cortical functions. Neurosci Biobehav Rev 2014; 54:120-30. [PMID: 25446945 DOI: 10.1016/j.neubiorev.2014.11.011] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 10/22/2014] [Accepted: 11/12/2014] [Indexed: 12/31/2022]
Abstract
Today, the idea that the integrity of the limbic thalamus is necessary for normal memory functions is well established. However, if the study of thalamic patients emphasized the anterior and the mediodorsal thalamus as the critical thalamic loci supporting cognitive functions, clinical studies have so far failed to attribute a specific role to each of these regions. In view of these difficulties, we review here the experimental data conducted in rodents harboring specific lesions of each thalamic region. These data clearly indicate a major functional dissociation within the limbic thalamus. The anterior thalamus provides critical support for hippocampal functions due to its cardinal location in the Papez circuit, while the mediodorsal thalamus may signal relevant information in a circuit encompassing the basolateral amygdala and the prefrontal cortex. Interestingly, while clinical studies have suggested that diencephalic pathologies may disconnect the medial temporal lobe from the cortex, experimental studies conducted in rodent show how this may differently affect distinct temporo-thalamo-cortical circuits, sharing the same general organization but supporting dissociable functions.
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45
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Pereira de Vasconcelos A, Cassel JC. The nonspecific thalamus: A place in a wedding bed for making memories last? Neurosci Biobehav Rev 2014; 54:175-96. [PMID: 25451763 DOI: 10.1016/j.neubiorev.2014.10.021] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 10/11/2014] [Accepted: 10/23/2014] [Indexed: 01/30/2023]
Abstract
We summarize anatomical, electrophysiological and behavioral evidence that the rostral intralaminar (ILN) and the reuniens and rhomboid (ReRh) nuclei that belong to the nonspecific thalamus, might be part of a hippocampo-cortico-thalamic network underlying consolidation of enduring declarative(-like) memories at systems level. The first part of this review describes the anatomical and functional organization of these thalamic nuclei. The second part presents the theoretical models supporting the active systems-level consolidation, a process that relies upon sleep specific field-potential oscillations occurring during both slow-wave sleep (SWS) and rapid eye movement (REM) sleep. The last part presents data in the rat showing that the lesion of the rostral ILN or of the ReRh specifically hinders the formation of remote spatial memories without affecting task acquisition or retrieval of a recent memory. These results showing a critical role of the ILN and ReRh nuclei in the transformation of a recent memory into a remote one are discussed in the context of their control of cortical arousal (ARAS) and of thalamo-cortico-thalamic synchronization.
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Affiliation(s)
- Anne Pereira de Vasconcelos
- Laboratoire de Neurosciences Cognitives et Adaptatives, UMR 7364, Université de Strasbourg, CNRS, Faculté de Psychologie Neuropôle de Strasbourg - GDR CNRS 2905, 12 rue Goethe, F-67000 Strasbourg, France.
| | - Jean-Christophe Cassel
- Laboratoire de Neurosciences Cognitives et Adaptatives, UMR 7364, Université de Strasbourg, CNRS, Faculté de Psychologie Neuropôle de Strasbourg - GDR CNRS 2905, 12 rue Goethe, F-67000 Strasbourg, France
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Aggleton JP, Nelson AJD. Why do lesions in the rodent anterior thalamic nuclei cause such severe spatial deficits? Neurosci Biobehav Rev 2014; 54:131-44. [PMID: 25195980 PMCID: PMC4462592 DOI: 10.1016/j.neubiorev.2014.08.013] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 08/07/2014] [Accepted: 08/27/2014] [Indexed: 12/30/2022]
Abstract
A dual hypothesis is introduced to explain the importance of these thalamic nuclei. ATN are vital for multiple spatial functions. ATN damage disrupts processing across distal limbic sites. Distal pathology caused by ATN damage disrupts plasticity and metabolic activity. ATN lesion effects reflect both their intrinsic importance and distal dysfunctions.
Lesions of the rodent anterior thalamic nuclei cause severe deficits to multiple spatial learning tasks. Possible explanations for these effects are examined, with particular reference to T-maze alternation. Anterior thalamic lesions not only impair allocentric place learning but also disrupt other spatial processes, including direction learning, path integration, and relative length discriminations, as well as aspects of nonspatial learning, e.g., temporal discriminations. Working memory tasks, such as T-maze alternation, appear particularly sensitive as they combine an array of these spatial and nonspatial demands. This sensitivity partly reflects the different functions supported by individual anterior thalamic nuclei, though it is argued that anterior thalamic lesion effects also arise from covert pathology in sites distal to the thalamus, most critically in the retrosplenial cortex and hippocampus. This two-level account, involving both local and distal lesion effects, explains the range and severity of the spatial deficits following anterior thalamic lesions. These findings highlight how the anterior thalamic nuclei form a key component in a series of interdependent systems that support multiple spatial functions.
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Affiliation(s)
- John P Aggleton
- School of Psychology, Cardiff University, Tower Building, 70 Park Place, Cardiff CF10 3AT, South Glamorganshire, Wales, UK
| | - Andrew J D Nelson
- School of Psychology, Cardiff University, Tower Building, 70 Park Place, Cardiff CF10 3AT, South Glamorganshire, Wales, UK.
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Hallock HL, Wang A, Shaw CL, Griffin AL. Transient inactivation of the thalamic nucleus reuniens and rhomboid nucleus produces deficits of a working-memory dependent tactile-visual conditional discrimination task. Behav Neurosci 2014; 127:860-6. [PMID: 24341710 DOI: 10.1037/a0034653] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Working memory depends on communication between the hippocampus and the prefrontal cortex (PFC); however, the neural circuitry that mediates interactions between these brain areas has not been well characterized. Two candidate structures are the thalamic reuniens (RE) and rhomboid (Rh) nuclei, which are reciprocally connected with both the hippocampus and PFC. These known anatomical connections suggest that RE/Rh may be involved in mediating hippocampal-prefrontal communication, and therefore may be critical for working memory processing. To test the hypothesis that RE/Rh are necessary for working memory, we trained separate groups of rats to perform 1 of 2 tasks in a T-maze. The first task was a working memory-dependent conditional discrimination (CDWM) task, and the second task was a nonworking memory-dependent conditional discrimination (CD) task. These tasks took place in the same maze, featured the same number of trials, and utilized the same cue (a tactile-visual maze insert). After rats had learned either task, RE/Rh were transiently inactivated with the GABAA receptor agonist muscimol, and performance was assessed. RE/Rh inactivation caused performance deficits on the CDWM task, but not the CD task. This result suggests that RE/Rh are a necessary component of working memory task performance, which is also thought to depend on the hippocampal-prefrontal circuit. RE/Rh inactivation did not cause a performance deficit on the CD task, suggesting that RE/Rh have dissociable contributions to working memory-dependent and nonworking memory-dependent tasks, independently of the known contributions of these 2 thalamic nuclei to the sensorimotor and attention-related aspects of other memory tasks.
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48
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Caramiphen edisylate as adjunct to standard therapy attenuates soman-induced seizures and cognitive deficits in rats. Neurotoxicol Teratol 2014; 44:89-104. [DOI: 10.1016/j.ntt.2014.06.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 05/30/2014] [Accepted: 06/03/2014] [Indexed: 02/06/2023]
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49
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Varela C. Thalamic neuromodulation and its implications for executive networks. Front Neural Circuits 2014; 8:69. [PMID: 25009467 PMCID: PMC4068295 DOI: 10.3389/fncir.2014.00069] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Accepted: 06/07/2014] [Indexed: 01/25/2023] Open
Abstract
The thalamus is a key structure that controls the routing of information in the brain. Understanding modulation at the thalamic level is critical to understanding the flow of information to brain regions involved in cognitive functions, such as the neocortex, the hippocampus, and the basal ganglia. Modulators contribute the majority of synapses that thalamic cells receive, and the highest fraction of modulator synapses is found in thalamic nuclei interconnected with higher order cortical regions. In addition, disruption of modulators often translates into disabling disorders of executive behavior. However, modulation in thalamic nuclei such as the midline and intralaminar groups, which are interconnected with forebrain executive regions, has received little attention compared to sensory nuclei. Thalamic modulators are heterogeneous in regards to their origin, the neurotransmitter they use, and the effect on thalamic cells. Modulators also share some features, such as having small terminal boutons and activating metabotropic receptors on the cells they contact. I will review anatomical and physiological data on thalamic modulators with these goals: first, determine to what extent the evidence supports similar modulator functions across thalamic nuclei; and second, discuss the current evidence on modulation in the midline and intralaminar nuclei in relation to their role in executive function.
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Affiliation(s)
- Carmen Varela
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology Cambridge, MA, USA
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Saalmann YB. Intralaminar and medial thalamic influence on cortical synchrony, information transmission and cognition. Front Syst Neurosci 2014; 8:83. [PMID: 24847225 PMCID: PMC4023070 DOI: 10.3389/fnsys.2014.00083] [Citation(s) in RCA: 209] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 04/21/2014] [Indexed: 11/15/2022] Open
Abstract
The intralaminar and medial thalamic nuclei are part of the higher-order thalamus, which receives little sensory input, and instead forms extensive cortico-thalamo-cortical pathways. The large mediodorsal thalamic nucleus predominantly connects with the prefrontal cortex, the adjacent intralaminar nuclei connect with fronto-parietal cortex, and the midline thalamic nuclei connect with medial prefrontal cortex and medial temporal lobe. Taking into account this connectivity pattern, it is not surprising that the intralaminar and medial thalamus has been implicated in a variety of cognitive functions, including memory processing, attention and orienting, as well as reward-based behavior. This review addresses how the intralaminar and medial thalamus may regulate information transmission in cortical circuits. A key neural mechanism may involve intralaminar and medial thalamic neurons modulating the degree of synchrony between different groups of cortical neurons according to behavioral demands. Such a thalamic-mediated synchronization mechanism may give rise to large-scale integration of information across multiple cortical circuits, consequently influencing the level of arousal and consciousness. Overall, the growing evidence supports a general role for the higher-order thalamus in the control of cortical information transmission and cognitive processing.
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Affiliation(s)
- Yuri B Saalmann
- Department of Psychology, University of Wisconsin-Madison Madison, WI, USA
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