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Milczarek MM, Perry JC, Amin E, Haniffa S, Hathaway T, Vann SD. Impairments in the early consolidation of spatial memories via group II mGluR agonism in the mammillary bodies. Sci Rep 2024; 14:5977. [PMID: 38472268 PMCID: PMC10933409 DOI: 10.1038/s41598-024-56015-3] [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: 12/13/2023] [Accepted: 02/29/2024] [Indexed: 03/14/2024] Open
Abstract
mGluR2 receptors are widely expressed in limbic brain regions associated with memory, including the hippocampal formation, retrosplenial and frontal cortices, as well as subcortical regions including the mammillary bodies. mGluR2/3 agonists have been proposed as potential therapeutics for neurological and psychiatric disorders, however, there is still little known about the role of these receptors in cognitive processes, including memory consolidation. To address this, we assessed the effect of the mGluR2/3 agonist, eglumetad, on spatial memory consolidation in both mice and rats. Using the novel place preference paradigm, we found that post-sample injections of eglumetad impaired subsequent spatial discrimination when tested 6 h later. Using the immediate early gene c-fos as a marker of neural activity, we showed that eglumetad injections reduced activity in a network of limbic brain regions including the hippocampus and mammillary bodies. To determine whether the systemic effects could be replicated with more targeted manipulations, we performed post-sample infusions of the mGluR2/3 agonist 2R,4R-APDC into the mammillary bodies. This impaired novelty discrimination on a place preference task and an object-in-place task, again highlighting the role of mGluR2/3 transmission in memory consolidation and demonstrating the crucial involvement of the mammillary bodies in post-encoding processing of spatial information.
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Affiliation(s)
- Michal M Milczarek
- School of Psychology & Neuroscience and Mental Health Innovation Institute, Cardiff University, 70 Park Place, Cardiff, CF10 3AT, UK
| | - James C Perry
- School of Psychology & Neuroscience and Mental Health Innovation Institute, Cardiff University, 70 Park Place, Cardiff, CF10 3AT, UK
| | - Eman Amin
- School of Psychology & Neuroscience and Mental Health Innovation Institute, Cardiff University, 70 Park Place, Cardiff, CF10 3AT, UK
| | - Salma Haniffa
- School of Psychology & Neuroscience and Mental Health Innovation Institute, Cardiff University, 70 Park Place, Cardiff, CF10 3AT, UK
| | - Thomas Hathaway
- School of Psychology & Neuroscience and Mental Health Innovation Institute, Cardiff University, 70 Park Place, Cardiff, CF10 3AT, UK
| | - Seralynne D Vann
- School of Psychology & Neuroscience and Mental Health Innovation Institute, Cardiff University, 70 Park Place, Cardiff, CF10 3AT, UK.
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2
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Żakowski W, Zawistowski P. Neurochemistry of the mammillary body. Brain Struct Funct 2023; 228:1379-1398. [PMID: 37378855 PMCID: PMC10335970 DOI: 10.1007/s00429-023-02673-4] [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: 10/25/2022] [Accepted: 06/19/2023] [Indexed: 06/29/2023]
Abstract
The mammillary body (MB) is a component of the extended hippocampal system and many studies have shown that its functions are vital for mnemonic processes. Together with other subcortical structures, such as the anterior thalamic nuclei and tegmental nuclei of Gudden, the MB plays a crucial role in the processing of spatial and working memory, as well as navigation in rats. The aim of this paper is to review the distribution of various substances in the MB of the rat, with a description of their possible physiological roles. The following groups of substances are reviewed: (1) classical neurotransmitters (glutamate and other excitatory transmitters, gamma-aminobutyric acid, acetylcholine, serotonin, and dopamine), (2) neuropeptides (enkephalins, substance P, cocaine- and amphetamine-regulated transcript, neurotensin, neuropeptide Y, somatostatin, orexins, and galanin), and (3) other substances (calcium-binding proteins and calcium sensor proteins). This detailed description of the chemical parcellation may facilitate a better understanding of the MB functions and its complex relations with other structures of the extended hippocampal system.
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Affiliation(s)
- Witold Żakowski
- Department of Animal and Human Physiology, Faculty of Biology, University of Gdańsk, Wita Stwosza 59, 80-308, Gdańsk, Poland.
| | - Piotr Zawistowski
- Department of Animal and Human Physiology, Faculty of Biology, University of Gdańsk, Wita Stwosza 59, 80-308, Gdańsk, Poland
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3
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Huang WC, Peng Z, Murdock MH, Liu L, Mathys H, Davila-Velderrain J, Jiang X, Chen M, Ng AP, Kim T, Abdurrob F, Gao F, Bennett DA, Kellis M, Tsai LH. Lateral mammillary body neurons in mouse brain are disproportionately vulnerable in Alzheimer's disease. Sci Transl Med 2023; 15:eabq1019. [PMID: 37075128 PMCID: PMC10511020 DOI: 10.1126/scitranslmed.abq1019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 03/31/2023] [Indexed: 04/21/2023]
Abstract
The neural circuits governing the induction and progression of neurodegeneration and memory impairment in Alzheimer's disease (AD) are incompletely understood. The mammillary body (MB), a subcortical node of the medial limbic circuit, is one of the first brain regions to exhibit amyloid deposition in the 5xFAD mouse model of AD. Amyloid burden in the MB correlates with pathological diagnosis of AD in human postmortem brain tissue. Whether and how MB neuronal circuitry contributes to neurodegeneration and memory deficits in AD are unknown. Using 5xFAD mice and postmortem MB samples from individuals with varying degrees of AD pathology, we identified two neuronal cell types in the MB harboring distinct electrophysiological properties and long-range projections: lateral neurons and medial neurons. lateral MB neurons harbored aberrant hyperactivity and exhibited early neurodegeneration in 5xFAD mice compared with lateral MB neurons in wild-type littermates. Inducing hyperactivity in lateral MB neurons in wild-type mice impaired performance on memory tasks, whereas attenuating aberrant hyperactivity in lateral MB neurons ameliorated memory deficits in 5xFAD mice. Our findings suggest that neurodegeneration may be a result of genetically distinct, projection-specific cellular dysfunction and that dysregulated lateral MB neurons may be causally linked to memory deficits in AD.
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Affiliation(s)
- Wen-Chin Huang
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
| | - Zhuyu Peng
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
| | - Mitchell H. Murdock
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
| | - Liwang Liu
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
| | - Hansruedi Mathys
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
- Broad Institute of MIT and Harvard; Cambridge, MA, 02139, USA
| | - Jose Davila-Velderrain
- Broad Institute of MIT and Harvard; Cambridge, MA, 02139, USA
- MIT Computer Science and Artificial Intelligence Laboratory; Cambridge, MA 02139, USA
| | - Xueqiao Jiang
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
| | - Maggie Chen
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
| | - Ayesha P. Ng
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
| | - TaeHyun Kim
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
| | - Fatema Abdurrob
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
| | - Fan Gao
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
| | - David A. Bennett
- Rush Alzheimer’s Disease Center, Rush University Medical Center; Chicago, IL 60612, USA
| | - Manolis Kellis
- Broad Institute of MIT and Harvard; Cambridge, MA, 02139, USA
- MIT Computer Science and Artificial Intelligence Laboratory; Cambridge, MA 02139, USA
| | - Li-Huei Tsai
- The Picower Institute for Learning and Memory, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology; Cambridge, MA, 02139, USA
- Broad Institute of MIT and Harvard; Cambridge, MA, 02139, USA
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4
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Hajdarovic KH, Yu D, Webb AE. Understanding the aging hypothalamus, one cell at a time. Trends Neurosci 2022; 45:942-954. [PMID: 36272823 PMCID: PMC9671837 DOI: 10.1016/j.tins.2022.10.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 09/21/2022] [Accepted: 10/03/2022] [Indexed: 11/17/2022]
Abstract
The hypothalamus is a brain region that integrates signals from the periphery and the environment to maintain organismal homeostasis. To do so, specialized hypothalamic neuropeptidergic neurons control a range of processes, such as sleep, feeding, the stress response, and hormone release. These processes are altered with age, which can affect longevity and contribute to disease status. Technological advances, such as single-cell RNA sequencing, are upending assumptions about the transcriptional identity of cell types in the hypothalamus and revealing how distinct cell types change with age. In this review, we summarize current knowledge about the contribution of hypothalamic functions to aging. We highlight recent single-cell studies interrogating distinct cell types of the mouse hypothalamus and suggest ways in which single-cell 'omics technologies can be used to further understand the aging hypothalamus and its role in longevity.
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Affiliation(s)
| | - Doudou Yu
- Graduate program in Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI 02912, USA
| | - Ashley E Webb
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI 02912, USA; Center on the Biology of Aging, Brown University, Providence, RI 02912, USA; Carney Institute for Brain Science, Brown University, Providence, RI 02912, USA; Center for Translational Neuroscience, Brown University, Providence, RI 02912, USA.
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5
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Chao OY, Nikolaus S, Yang YM, Huston JP. Neuronal circuitry for recognition memory of object and place in rodent models. Neurosci Biobehav Rev 2022; 141:104855. [PMID: 36089106 PMCID: PMC10542956 DOI: 10.1016/j.neubiorev.2022.104855] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 08/23/2022] [Accepted: 08/30/2022] [Indexed: 10/14/2022]
Abstract
Rats and mice are used for studying neuronal circuits underlying recognition memory due to their ability to spontaneously remember the occurrence of an object, its place and an association of the object and place in a particular environment. A joint employment of lesions, pharmacological interventions, optogenetics and chemogenetics is constantly expanding our knowledge of the neural basis for recognition memory of object, place, and their association. In this review, we summarize current studies on recognition memory in rodents with a focus on the novel object preference, novel location preference and object-in-place paradigms. The evidence suggests that the medial prefrontal cortex- and hippocampus-connected circuits contribute to recognition memory for object and place. Under certain conditions, the striatum, medial septum, amygdala, locus coeruleus and cerebellum are also involved. We propose that the neuronal circuitry for recognition memory of object and place is hierarchically connected and constructed by different cortical (perirhinal, entorhinal and retrosplenial cortices), thalamic (nucleus reuniens, mediodorsal and anterior thalamic nuclei) and primeval (hypothalamus and interpeduncular nucleus) modules interacting with the medial prefrontal cortex and hippocampus.
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Affiliation(s)
- Owen Y Chao
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812, USA
| | - Susanne Nikolaus
- Department of Nuclear Medicine, University Hospital Düsseldorf, Heinrich-Heine University, 40225 Düsseldorf, Germany
| | - Yi-Mei Yang
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812, USA; Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Joseph P Huston
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, Heinrich-Heine University, 40225 Düsseldorf, Germany.
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6
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Dillingham CM, Milczarek MM, Perry JC, Vann SD. Time to put the mammillothalamic pathway into context. Neurosci Biobehav Rev 2021; 121:60-74. [PMID: 33309908 PMCID: PMC8137464 DOI: 10.1016/j.neubiorev.2020.11.031] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 10/10/2020] [Accepted: 11/13/2020] [Indexed: 12/11/2022]
Abstract
The medial diencephalon, in particular the mammillary bodies and anterior thalamic nuclei, has long been linked to memory and amnesia. The mammillary bodies provide a dense input into the anterior thalamic nuclei, via the mammillothalamic tract. In both animal models, and in patients, lesions of the mammillary bodies, mammillothalamic tract and anterior thalamic nuclei all produce severe impairments in temporal and contextual memory, yet it is uncertain why these regions are critical. Mounting evidence from electrophysiological and neural imaging studies suggests that mammillothalamic projections exercise considerable distal influence over thalamo-cortical and hippocampo-cortical interactions. Here, we outline how damage to the mammillary body-anterior thalamic axis, in both patients and animal models, disrupts behavioural performance on tasks that relate to contextual ("where") and temporal ("when") processing. Focusing on the medial mammillary nuclei as a possible 'theta-generator' (through their interconnections with the ventral tegmental nucleus of Gudden) we discuss how the mammillary body-anterior thalamic pathway may contribute to the mechanisms via which the hippocampus and neocortex encode representations of experience.
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Affiliation(s)
- Christopher M Dillingham
- School of Psychology, Neuroscience and Mental Health Research Institute, Cardiff University, Cardiff, CF10 3AT, UK
| | - Michal M Milczarek
- School of Psychology, Neuroscience and Mental Health Research Institute, Cardiff University, Cardiff, CF10 3AT, UK
| | - James C Perry
- School of Psychology, Neuroscience and Mental Health Research Institute, Cardiff University, Cardiff, CF10 3AT, UK
| | - Seralynne D Vann
- School of Psychology, Neuroscience and Mental Health Research Institute, Cardiff University, Cardiff, CF10 3AT, UK.
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7
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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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8
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Aggleton JP, Nelson AJD. Distributed interactive brain circuits for object-in-place memory: A place for time? Brain Neurosci Adv 2020; 4:2398212820933471. [PMID: 32954003 PMCID: PMC7479857 DOI: 10.1177/2398212820933471] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 05/15/2020] [Indexed: 12/23/2022] Open
Abstract
Rodents will spontaneously learn the location of an individual object, an
ability captured by the object-in-place test. This review considers
the network of structures supporting this behavioural test, as well as
some potential confounds that may affect interpretation. A
hierarchical approach is adopted, as we first consider those brain
regions necessary for two simpler, ‘precursor’ tests (object
recognition and object location). It is evident that performing the
object-in-place test requires an array of areas additional to those
required for object recognition or object location. These additional
areas include the rodent medial prefrontal cortex and two thalamic
nuclei (nucleus reuniens and the medial dorsal nucleus), both densely
interconnected with prefrontal areas. Consequently, despite the need
for object and location information to be integrated for the
object-in-place test, for example, via the hippocampus, other
contributions are necessary. These contributions stem from how
object-in-place is a test of associative recognition, as none of the
individual elements in the test phase are novel. Parallels between the
structures required for object-in-place and for recency
discriminations, along with a re-examination of the demands of the
object-in-place test, signal the integration of temporal information
within what is usually regarded as a spatial-object test.
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Affiliation(s)
- John P Aggleton
- School of Psychology, Cardiff University, Cardiff, Wales, UK
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9
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Dillingham CM, Milczarek MM, Perry JC, Frost BE, Parker GD, Assaf Y, Sengpiel F, O'Mara SM, Vann SD. Mammillothalamic Disconnection Alters Hippocampocortical Oscillatory Activity and Microstructure: Implications for Diencephalic Amnesia. J Neurosci 2019; 39:6696-6713. [PMID: 31235646 PMCID: PMC6703878 DOI: 10.1523/jneurosci.0827-19.2019] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 06/08/2019] [Accepted: 06/10/2019] [Indexed: 01/13/2023] Open
Abstract
Diencephalic amnesia can be as debilitating as the more commonly known temporal lobe amnesia, yet the precise contribution of diencephalic structures to memory processes remains elusive. Across four cohorts of male rats, we used discrete lesions of the mammillothalamic tract to model aspects of diencephalic amnesia and assessed the impact of these lesions on multiple measures of activity and plasticity within the hippocampus and retrosplenial cortex. Lesions of the mammillothalamic tract had widespread indirect effects on hippocampocortical oscillatory activity within both theta and gamma bands. Both within-region oscillatory activity and cross-regional synchrony were altered. The network changes were state-dependent, displaying different profiles during locomotion and paradoxical sleep. Consistent with the associations between oscillatory activity and plasticity, complementary analyses using several convergent approaches revealed microstructural changes, which appeared to reflect a suppression of learning-induced plasticity in lesioned animals. Together, these combined findings suggest a mechanism by which damage to the medial diencephalon can impact upon learning and memory processes, highlighting an important role for the mammillary bodies in the coordination of hippocampocortical activity.SIGNIFICANCE STATEMENT Information flow within the Papez circuit is critical to memory. Damage to ascending mammillothalamic projections has consistently been linked to amnesia in humans and spatial memory deficits in animal models. Here we report on the changes in hippocampocortical oscillatory dynamics that result from chronic lesions of the mammillothalamic tract and demonstrate, for the first time, that the mammillary bodies, independently of the supramammillary region, contribute to frequency modulation of hippocampocortical theta oscillations. Consistent with the associations between oscillatory activity and plasticity, the lesions also result in a suppression of learning-induced plasticity. Together, these data support new functional models whereby mammillary bodies are important for coordinating hippocampocortical activity rather than simply being a relay of hippocampal information as previously assumed.
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Affiliation(s)
- Christopher M Dillingham
- School of Psychology, Cardiff University, Cardiff CF10 3AT, United Kingdom
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland
| | - Michal M Milczarek
- School of Psychology, Cardiff University, Cardiff CF10 3AT, United Kingdom
| | - James C Perry
- School of Psychology, Cardiff University, Cardiff CF10 3AT, United Kingdom
| | - Bethany E Frost
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland
| | - Greg D Parker
- EMRIC, Cardiff University, Cardiff CF10 3AX, United Kingdom
| | - Yaniv Assaf
- George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel 6997801, and
| | - Frank Sengpiel
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, United Kingdom
| | - Shane M O'Mara
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland
| | - Seralynne D Vann
- School of Psychology, Cardiff University, Cardiff CF10 3AT, United Kingdom,
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10
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The Cognitive Thalamus as a Gateway to Mental Representations. J Neurosci 2018; 39:3-14. [PMID: 30389839 PMCID: PMC6325267 DOI: 10.1523/jneurosci.0479-18.2018] [Citation(s) in RCA: 173] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 10/24/2018] [Accepted: 10/28/2018] [Indexed: 01/16/2023] Open
Abstract
Historically, the thalamus has been viewed as little more than a relay, simply transferring information to key players of the cast, the cortex and hippocampus, without providing any unique functional contribution. In recent years, evidence from multiple laboratories researching different thalamic nuclei has contradicted this idea of the thalamus as a passive structure. Dated models of thalamic functions are being pushed aside, revealing a greater and far more complex contribution of the thalamus for cognition. In this Viewpoints article, we show how recent data support novel views of thalamic functions that emphasize integrative roles in cognition, ranging from learning and memory to flexible adaption. We propose that these apparently separate cognitive functions may indeed be supported by a more general role in shaping mental representations. Several features of thalamocortical circuits are consistent with this suggested role, and we highlight how divergent and convergent thalamocortical and corticothalamic pathways may complement each other to support these functions. Furthermore, the role of the thalamus for subcortical integration is highlighted as a key mechanism for maintaining and updating representations. Finally, we discuss future areas of research and stress the importance of incorporating new experimental findings into existing knowledge to continue developing thalamic models. The presence of thalamic pathology in a number of neurological conditions reinforces the need to better understand the role of this region in cognition.
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Dalrymple-Alford JC, Perry BAL. Lesions of the mammillothalamic tract and anterior thalamic nuclei: Response to Vann and Nelson (2018). Hippocampus 2018; 28:694-697. [PMID: 29742808 DOI: 10.1002/hipo.22963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 05/06/2018] [Accepted: 05/07/2018] [Indexed: 11/11/2022]
Affiliation(s)
- John C Dalrymple-Alford
- Department of Psychology, New Zealand Brain Research Institute, University of Canterbury and Brain Research New Zealand, Christchurch, 8041, New Zealand
| | - Brook A L Perry
- Department of Experimental Psychology, University of Oxford, Oxford, OX1 3SR, United Kingdom
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12
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Vann SD, Nelson AJD. Anterior thalamic nuclei lesions have a greater impact than mammillothalamic tract lesions on the extended hippocampal system: A reply. Hippocampus 2018; 28:691-693. [PMID: 29671918 DOI: 10.1002/hipo.22953] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 04/13/2018] [Indexed: 12/12/2022]
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13
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Unfolding the cognitive map: The role of hippocampal and extra-hippocampal substrates based on a systems analysis of spatial processing. Neurobiol Learn Mem 2018; 147:90-119. [DOI: 10.1016/j.nlm.2017.11.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 11/17/2017] [Accepted: 11/21/2017] [Indexed: 01/03/2023]
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14
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Perry BAL, Mercer SA, Barnett SC, Lee J, Dalrymple-Alford JC. Anterior thalamic nuclei lesions have a greater impact than mammillothalamic tract lesions on the extended hippocampal system. Hippocampus 2017; 28:121-135. [DOI: 10.1002/hipo.22815] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Revised: 11/10/2017] [Accepted: 11/15/2017] [Indexed: 11/05/2022]
Affiliation(s)
- Brook A. L. Perry
- Department of Psychology; University of Canterbury; Christchurch New Zealand
- Brain Research New Zealand, co-hosted by Auckland and Otago Universities; Auckland New Zealand
| | - Stephanie A. Mercer
- Department of Biochemistry; University of Otago; Dunedin
- Brain Research New Zealand, co-hosted by Auckland and Otago Universities; Auckland New Zealand
| | - Sophie C. Barnett
- Department of Psychology; University of Canterbury; Christchurch New Zealand
- Brain Research New Zealand, co-hosted by Auckland and Otago Universities; Auckland New Zealand
| | - Jungah Lee
- Department of Psychology; University of Canterbury; Christchurch New Zealand
| | - John C. Dalrymple-Alford
- Department of Psychology; University of Canterbury; Christchurch New Zealand
- Brain Research New Zealand, co-hosted by Auckland and Otago Universities; Auckland New Zealand
- New Zealand Brain Research Institute; Christchurch New Zealand
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15
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The effect of pharmacological inactivation of the mammillary body and anterior thalamic nuclei on hippocampal theta rhythm in urethane-anesthetized rats. Neuroscience 2017; 362:196-205. [PMID: 28844761 DOI: 10.1016/j.neuroscience.2017.08.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 08/18/2017] [Accepted: 08/23/2017] [Indexed: 02/02/2023]
Abstract
The mammillary body (MB) and the anterior thalamic nuclei (ATN) are closely related structures, which take part in learning and memory processes. However, the exact role of these structures has remained unclear. In both structures neurons firing according to hippocampal theta rhythm have been found, mainly in the medial mammillary nucleus (MM) and anteroventral thalamic nucleus (AV). These neurons are driven by descending projections from the hippocampal formation and are thought to convey theta rhythm back to the hippocampus (HP). We argue that the MB-ATN axis not only relays theta signal, but may also modulate it. To examine it, we performed a pharmacological inactivation of the MM and AV by local infusion of procaine, and measured changes in theta activity in selected structures of the extended hippocampal system in urethane-anesthetized rats. The inactivation of the MM resulted in decrease in EEG power in the HP and AV, the most evidently in the lower theta frequency bands, i.e. 3-5Hz in the HP (down to 9.2% in 3- to 4-Hz band and 37.6% in 4- to 5-Hz band, in comparison to the power in the control conditions) and 3-4Hz in the AV (down to 24.9%). After the AV inactivation, hippocampal EEG power decreased in theta frequency bands of 3-8Hz (down to 61.6% in 6- to 7-Hz band and 69.4% in 7- to 8-Hz band). Our results suggest that the role of the MB-ATN axis in regulating theta rhythm signaling may be much more important than has been speculated so far.
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Kanoski SE, Grill HJ. Hippocampus Contributions to Food Intake Control: Mnemonic, Neuroanatomical, and Endocrine Mechanisms. Biol Psychiatry 2017; 81:748-756. [PMID: 26555354 PMCID: PMC4809793 DOI: 10.1016/j.biopsych.2015.09.011] [Citation(s) in RCA: 158] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 08/22/2015] [Accepted: 09/21/2015] [Indexed: 10/23/2022]
Abstract
Food intake is a complex behavior that can occur or cease to occur for a multitude of reasons. Decisions about where, when, what, and how much to eat are not merely reflexive responses to food-relevant stimuli or to changes in energy status. Rather, feeding behavior is modulated by various contextual factors and by previous experiences. The data reviewed here support the perspective that neurons in multiple hippocampal subregions constitute an important neural substrate linking the external context, the internal context, and mnemonic and cognitive information to control both appetitive and ingestive behavior. Feeding behavior is heavily influenced by hippocampal-dependent mnemonic functions, including episodic meal-related memories and conditional learned associations between food-related stimuli and postingestive consequences. These mnemonic processes are undoubtedly influenced by both external and internal factors relating to food availability, location, and physiological energy status. The afferent and efferent neuroanatomical connectivity of the subregions of the hippocampus is reviewed with regard to the integration of visuospatial and olfactory sensory information (the external context) with endocrine and gastrointestinal interoceptive stimuli (the internal context). Also discussed are recent findings demonstrating that peripherally derived endocrine signals act on receptors in hippocampal neurons to reduce (leptin, glucagon-like peptide-1) or increase (ghrelin) food intake and learned food reward-driven responding, thereby highlighting endocrine and neuropeptidergic signaling in hippocampal neurons as a novel substrate of importance in the higher-order regulation of feeding behavior.
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Affiliation(s)
- Scott E. Kanoski
- Department of Biological Sciences, University of Southern California
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Nelson AJD, Vann SD. The importance of mammillary body efferents for recency memory: towards a better understanding of diencephalic amnesia. Brain Struct Funct 2016; 222:2143-2156. [PMID: 27783220 PMCID: PMC5504269 DOI: 10.1007/s00429-016-1330-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 10/19/2016] [Indexed: 11/27/2022]
Abstract
Despite being historically one of the first brain regions linked to memory loss, there remains controversy over the core features of diencephalic amnesia as well as the critical site for amnesia to occur. The mammillary bodies and thalamus appear to be the primary locus of pathology in the cases of diencephalic amnesia, but the picture is complicated by the lack of patients with circumscribed damage. Impaired temporal memory is a consistent neuropsychological finding in Korsakoff syndrome patients, but again, it is unclear whether this deficit is attributable to pathology within the diencephalon or concomitant frontal lobe dysfunction. To address these issues, we used an animal model of diencephalic amnesia and examined the effect of mammillothalamic tract lesions on tests of recency memory. The mammillothalamic tract lesions severely disrupted recency judgements involving multiple items but left intact both recency and familiarity judgements for single items. Subsequently, we used disconnection procedures to assess whether this deficit reflects the indirect involvement of the prefrontal cortex. Crossed-lesion rats, with unilateral lesions of the mammillothalamic tract and medial prefrontal cortex in contralateral hemispheres, were unimpaired on the same recency tests. These results provide the first evidence for the selective importance of mammillary body efferents for recency memory. Moreover, this contribution to recency memory is independent of the prefrontal cortex. More broadly, these findings identify how specific diencephalic structures are vital for key elements of event memory.
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Affiliation(s)
- Andrew J D Nelson
- School of Psychology, Cardiff University, 70 Park Place, Cardiff, CF10 3AT, UK.
| | - Seralynne D Vann
- School of Psychology, Cardiff University, 70 Park Place, Cardiff, CF10 3AT, UK
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Frizzati A, Milczarek MM, Sengpiel F, Thomas KL, Dillingham CM, Vann SD. Comparable reduction in Zif268 levels and cytochrome oxidase activity in the retrosplenial cortex following mammillothalamic tract lesions. Neuroscience 2016; 330:39-49. [PMID: 27233617 PMCID: PMC4936792 DOI: 10.1016/j.neuroscience.2016.05.030] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Revised: 05/13/2016] [Accepted: 05/16/2016] [Indexed: 11/19/2022]
Abstract
Mammillothalamic tract lesions impaired T-maze alternation performance. Mammillothalamic tract lesions reduced Zif268 levels in retrosplenial cortex. Mammillothalamic tract lesions reduced cytochrome oxidase in retrosplenial cortex. No changes were found in the dorsal hippocampus. These distal changes may contribute to the memory impairments.
Damage to the mammillothalamic tract (MTT) produces memory impairments in both humans and rats, yet it is still not clear why this diencephalic pathway is vital for memory. One suggestion is that it is an important route for midbrain inputs to reach a wider cortical and subcortical network that supports memory. Consistent with this idea, MTT lesions produce widespread hypoactivity in distal brain regions as measured by the immediate-early gene, c-fos. To determine whether these findings were selective to c-fos or reflected more general changes in neuronal function, we assessed the effects of MTT lesions on the expression of the immediate-early gene protein, Zif268 and the metabolic marker, cytochrome oxidase, in the retrosplenial cortex and hippocampus. The lesions decreased levels of both activity markers in the superficial and deep layers of the retrosplenial cortex in both its granular and dysgranular subregions. In contrast, no significant changes were observed in the hippocampus, despite the MTT-lesioned animals showing marked impairments on T-maze alternation. These findings are consistent with MTT lesions providing important, indirect inputs for normal retrosplenial cortex functioning. These distal functional changes may contribute to the memory impairments observed after MTT lesions.
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Affiliation(s)
- Aura Frizzati
- School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff CF10 3AT, UK; School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK
| | - Michal M Milczarek
- School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff CF10 3AT, UK; School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK
| | - Frank Sengpiel
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK
| | - Kerrie L Thomas
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK
| | - Christopher M Dillingham
- School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff CF10 3AT, UK; Institute of Neuroscience, Trinity College Dublin, Lloyd Building, College Green, Dublin 2, Ireland
| | - Seralynne D Vann
- School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff CF10 3AT, UK.
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Baloyannis SJ, Mavroudis I, Baloyannis IS, Costa VG. Mammillary Bodies in Alzheimer's Disease: A Golgi and Electron Microscope Study. Am J Alzheimers Dis Other Demen 2016; 31:247-56. [PMID: 26399484 PMCID: PMC10852917 DOI: 10.1177/1533317515602548] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder, characterized by irreversible memory decline, concerning no rarely spatial memory and orientation, alterations of the mood and personality, gradual loss of motor skills, and substantial loss of capacities obtained by previous long education. We attempted to describe the morphological findings of the mammillary bodies in early cases of AD. Samples were processed for electron microscopy and silver impregnation techniques. The nuclei of the mammillary bodies demonstrated a substantial decrease in the neuronal population and marked abbreviation of dendritic arbors. Decrease in spine density and morphological abnormalities of dendritic spines was also seen. Synaptic alterations were prominent. Alzheimer's pathology, such as deposits of amyloid-β peptide and neurofibrillary degeneration, was minimal. Electron microscopy revealed mitochondrial alterations and fragmentation of Golgi apparatus, associated frequently with synaptic pathology.
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Affiliation(s)
- Stavros J Baloyannis
- Department of Neurology, Laboratory of Neuropathology and Electron Microscopy, Aristotelian University, Thessaloniki, Greece Laboratory of Neuropathology, Institute for Research on Alzheimer's Disease, Iraklion, Greece
| | - Ioannis Mavroudis
- Department of Neurology, Laboratory of Neuropathology and Electron Microscopy, Aristotelian University, Thessaloniki, Greece
| | - Ioannis S Baloyannis
- Department of Neurology, Laboratory of Neuropathology and Electron Microscopy, Aristotelian University, Thessaloniki, Greece
| | - Vassiliki G Costa
- Department of Neurology, Laboratory of Neuropathology and Electron Microscopy, Aristotelian University, Thessaloniki, Greece Laboratory of Neuropathology, Institute for Research on Alzheimer's Disease, Iraklion, Greece
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Endogenous IL-6 of mesenchymal stem cell improves behavioral outcome of hypoxic-ischemic brain damage neonatal rats by supressing apoptosis in astrocyte. Sci Rep 2016; 6:18587. [PMID: 26766745 PMCID: PMC4725911 DOI: 10.1038/srep18587] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 11/23/2015] [Indexed: 01/01/2023] Open
Abstract
Mesenchymal stem cell (MSC) transplantation reduces the neurological impairment caused by hypoxic-ischemic brain damage (HIBD) via immunomodulation. In the current study, we found that MSC transplantation improved learning and memory function and enhanced long-term potentiation in neonatal rats subjected to HIBD and the amount of IL-6 released from MSCs was far greater than that of other cytokines. However, the neuroprotective effect of MSCs infected with siIL-6-transduced recombinant lentivirus (siIL-6 MSCs) was significantly weakened in the behavioural tests and electrophysiological analysis. Meanwhile, the hippocampal IL-6 levels were decreased following siIL-6 MSC transplantation. In vitro, the levels of IL-6 release and the levels of IL-6R and STAT3 expression were increased in both primary neurons and astrocytes subjected to oxygen and glucose deprivation (OGD) following MSCs co-culture. The anti-apoptotic protein Bcl-2 was upregulated and the pro-apoptotic protein Bax was downregulated in OGD-injured astrocytes co-cultured with MSCs. However, the siIL-6 MSCs suppressed ratio of Bcl-2/Bax in the injured astrocytes and induced apoptosis number of the injured astrocytes. Taken together, these data suggest that the neuroprotective effect of MSC transplantation in neonatal HIBD rats is partly mediated by IL-6 to enhance anti-apoptosis of injured astrocytes via the IL-6/STAT3 signaling pathway.
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Vann SD, Nelson AJD. The mammillary bodies and memory: more than a hippocampal relay. PROGRESS IN BRAIN RESEARCH 2015; 219:163-85. [PMID: 26072239 PMCID: PMC4498492 DOI: 10.1016/bs.pbr.2015.03.006] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Although the mammillary bodies were one of the first neural structures to be implicated in memory, it has long been assumed that their main function was to act primarily as a hippocampal relay, passing information on to the anterior thalamic nuclei and from there to the cingulate cortex. This view not only afforded the mammillary bodies no independent role in memory, it also neglected the potential significance of other, nonhippocampal, inputs to the mammillary bodies. Recent advances have transformed the picture, revealing that projections from the tegmental nuclei of Gudden, and not the hippocampal formation, are critical for sustaining mammillary body function. By uncovering a role for the mammillary bodies that is independent of its subicular inputs, this work signals the need to consider a wider network of structures that form the neural bases of episodic memory.
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Kinnavane L, Albasser MM, Aggleton JP. Advances in the behavioural testing and network imaging of rodent recognition memory. Behav Brain Res 2015; 285:67-78. [PMID: 25106740 PMCID: PMC4383364 DOI: 10.1016/j.bbr.2014.07.049] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 07/23/2014] [Accepted: 07/28/2014] [Indexed: 12/12/2022]
Abstract
Research into object recognition memory has been galvanised by the introduction of spontaneous preference tests for rodents. The standard task, however, contains a number of inherent shortcomings that reduce its power. Particular issues include the problem that individual trials are time consuming, so limiting the total number of trials in any condition. In addition, the spontaneous nature of the behaviour and the variability between test objects add unwanted noise. To combat these issues, the 'bow-tie maze' was introduced. Although still based on the spontaneous preference of novel over familiar stimuli, the ability to give multiple trials within a session without handling the rodents, as well as using the same objects as both novel and familiar samples on different trials, overcomes key limitations in the standard task. Giving multiple trials within a single session also creates new opportunities for functional imaging of object recognition memory. A series of studies are described that examine the expression of the immediate-early gene, c-fos. Object recognition memory is associated with increases in perirhinal cortex and area Te2 c-fos activity. When rats explore novel objects the pathway from the perirhinal cortex to lateral entorhinal cortex, and then to the dentate gyrus and CA3, is engaged. In contrast, when familiar objects are explored the pathway from the perirhinal cortex to lateral entorhinal cortex, and then to CA1, takes precedence. The switch to the perforant pathway (novel stimuli) from the temporoammonic pathway (familiar stimuli) may assist the enhanced associative learning promoted by novel stimuli.
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Affiliation(s)
- Lisa Kinnavane
- School of Psychology, Cardiff University, Tower Building, 70 Park Place, Cardiff, Wales CF10 3AT, United Kingdom.
| | - Mathieu M Albasser
- School of Psychology, Cardiff University, Tower Building, 70 Park Place, Cardiff, Wales CF10 3AT, United Kingdom
| | - John P Aggleton
- School of Psychology, Cardiff University, Tower Building, 70 Park Place, Cardiff, Wales CF10 3AT, United Kingdom
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23
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Moving beyond standard procedures to assess spontaneous recognition memory. Neurosci Biobehav Rev 2015; 53:37-51. [PMID: 25842032 DOI: 10.1016/j.neubiorev.2015.03.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 03/19/2015] [Accepted: 03/25/2015] [Indexed: 11/23/2022]
Abstract
This review will consider how spontaneous tasks have been applied alongside neuroscientific techniques to test complex forms of recognition memory for objects and their environmental features, e.g. the spatial location of an object or the context in which it is presented. We discuss studies that investigate the roles of the perirhinal cortex and the hippocampus in recognition memory using standard testing paradigms, and consider how these findings contribute to the ongoing debate about whether recognition memory is a single unitary process or multiple processes that can be dissociated anatomically and functionally. Due to the wide use of spontaneous tasks, the need for improved procedures that reduce animal use is acknowledged, with multiple trial paradigms discussed as a novel way of reducing variability and animal numbers in these tasks. The importance of improving translation of animal models to humans is highlighted, with emphasis on a shift away from relying on the phenomenological experience of human subjects.
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Dillingham CM, Frizzati A, Nelson AJD, Vann SD. How do mammillary body inputs contribute to anterior thalamic function? Neurosci Biobehav Rev 2014; 54:108-19. [PMID: 25107491 PMCID: PMC4462591 DOI: 10.1016/j.neubiorev.2014.07.025] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 07/18/2014] [Accepted: 07/28/2014] [Indexed: 11/25/2022]
Abstract
It has long been assumed that the main function of the mammillary bodies is to provide a relay for indirect hippocampal inputs to the anterior thalamic nuclei. Such models afford the mammillary bodies no independent role in memory and overlook the importance of their other, non-hippocampal, inputs. This review focuses on recent advances that herald a new understanding of the importance of the mammillary bodies, and their inputs from the limbic midbrain, for anterior thalamic function. It has become apparent that the mammillary bodies' contribution to memory is not dependent on afferents from the subicular complex. Rather, the ventral tegmental nucleus of Gudden is a vital source of inputs that support memory processes within the medial mammillary bodies. In parallel, the lateral mammillary bodies, via their connections with the dorsal tegmental nucleus of Gudden, are critical for generating head-direction signals. These two parallel, but distinct, information streams converge on the anterior thalamic nuclei and support different aspects of spatial memory.
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Affiliation(s)
- Christopher M Dillingham
- School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff CF10 3AT, United Kingdom
| | - Aura Frizzati
- School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff CF10 3AT, United Kingdom
| | - Andrew J D Nelson
- School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff CF10 3AT, United Kingdom
| | - Seralynne D Vann
- School of Psychology, Cardiff University, Tower Building, Park Place, Cardiff CF10 3AT, United Kingdom.
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