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Yang X, Cacucci F, Burgess N, Wills TJ, Chen G. Visual boundary cues suffice to anchor place and grid cells in virtual reality. Curr Biol 2024:S0960-9822(24)00466-4. [PMID: 38701787 DOI: 10.1016/j.cub.2024.04.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 03/01/2024] [Accepted: 04/10/2024] [Indexed: 05/05/2024]
Abstract
The hippocampal formation contains neurons responsive to an animal's current location and orientation, which together provide the organism with a neural map of space.1,2,3 Spatially tuned neurons rely on external landmark cues and internally generated movement information to estimate position.4,5 An important class of landmark cue are the boundaries delimiting an environment, which can define place cell field position6,7 and stabilize grid cell firing.8 However, the precise nature of the sensory information used to detect boundaries remains unknown. We used 2-dimensional virtual reality (VR)9 to show that visual cues from elevated walls surrounding the environment are both sufficient and necessary to stabilize place and grid cell responses in VR, when only visual and self-motion cues are available. By contrast, flat boundaries formed by the edges of a textured floor did not stabilize place and grid cells, indicating only specific forms of visual boundary stabilize hippocampal spatial firing. Unstable grid cells retain internally coherent, hexagonally arranged firing fields, but these fields "drift" with respect to the virtual environment over periods >5 s. Optic flow from a virtual floor does not slow drift dynamics, emphasizing the importance of boundary-related visual information. Surprisingly, place fields are more stable close to boundaries even with floor and wall cues removed, suggesting invisible boundaries are inferred using the motion of a discrete, separate cue (a beacon signaling reward location). Subsets of place cells show allocentric directional tuning toward the beacon, with strength of tuning correlating with place field stability when boundaries are removed.
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Affiliation(s)
- Xiuting Yang
- School of Biological and Behavioural Sciences, Queen Mary University of London, 327 Mile End Road, London E1 4NS, UK
| | - Francesca Cacucci
- Department of Neuroscience, Physiology, and Pharmacology, University College London, Gower Street, London WC1E 6BT, UK
| | - Neil Burgess
- Institute of Cognitive Neuroscience, University College London, 17 Queen Square, London WC1N 3AZ, UK; Queen Square Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Thomas Joseph Wills
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK.
| | - Guifen Chen
- School of Biological and Behavioural Sciences, Queen Mary University of London, 327 Mile End Road, London E1 4NS, UK.
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2
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Bevandić J, Chareyron LJ, Bachevalier J, Cacucci F, Genzel L, Newcombe NS, Vargha-Khadem F, Ólafsdóttir HF. Episodic memory development: Bridging animal and human research. Neuron 2024; 112:1060-1080. [PMID: 38359826 DOI: 10.1016/j.neuron.2024.01.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 12/22/2023] [Accepted: 01/19/2024] [Indexed: 02/17/2024]
Abstract
Human episodic memory is not functionally evident until about 2 years of age and continues to develop into the school years. Behavioral studies have elucidated this developmental timeline and its constituent processes. In tandem, lesion and neurophysiological studies in non-human primates and rodents have identified key neural substrates and circuit mechanisms that may underlie episodic memory development. Despite this progress, collaborative efforts between psychologists and neuroscientists remain limited, hindering progress. Here, we seek to bridge human and non-human episodic memory development research by offering a comparative review of studies using humans, non-human primates, and rodents. We highlight critical theoretical and methodological issues that limit cross-fertilization and propose a common research framework, adaptable to different species, that may facilitate cross-species research endeavors.
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Affiliation(s)
- Juraj Bevandić
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands
| | - Loïc J Chareyron
- Cognitive Neuroscience and Neuropsychiatry, Developmental Neurosciences, University College London Great Ormond Street Institute of Child Health, London, UK; Laboratory of Brain and Cognitive Development, Institute of Psychology, University of Lausanne, Lausanne, Switzerland
| | - Jocelyne Bachevalier
- Division of Developmental and Cognitive Neuroscience, Emory National Primate Research Center, Department of Psychology, Emory University, Atlanta, GA, USA.
| | - Francesca Cacucci
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK.
| | - Lisa Genzel
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands.
| | - Nora S Newcombe
- Department of Psychology, Temple University, Philadelphia, PA, USA.
| | - Faraneh Vargha-Khadem
- Cognitive Neuroscience and Neuropsychiatry, Developmental Neurosciences, University College London Great Ormond Street Institute of Child Health, London, UK.
| | - H Freyja Ólafsdóttir
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands.
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3
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Muessig L, Ribeiro Rodrigues F, Bjerknes TL, Towse BW, Barry C, Burgess N, Moser EI, Moser MB, Cacucci F, Wills TJ. Environment geometry alters subiculum boundary vector cell receptive fields in adulthood and early development. Nat Commun 2024; 15:982. [PMID: 38302455 PMCID: PMC10834499 DOI: 10.1038/s41467-024-45098-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 01/15/2024] [Indexed: 02/03/2024] Open
Abstract
Boundaries to movement form a specific class of landmark information used for navigation: Boundary Vector Cells (BVCs) are neurons which encode an animal's location as a vector displacement from boundaries. Here we characterise the prevalence and spatial tuning of subiculum BVCs in adult and developing male rats, and investigate the relationship between BVC spatial firing and boundary geometry. BVC directional tunings align with environment walls in squares, but are uniformly distributed in circles, demonstrating that environmental geometry alters BVC receptive fields. Inserted barriers uncover both excitatory and inhibitory components to BVC receptive fields, demonstrating that inhibitory inputs contribute to BVC field formation. During post-natal development, subiculum BVCs mature slowly, contrasting with the earlier maturation of boundary-responsive cells in upstream Entorhinal Cortex. However, Subiculum and Entorhinal BVC receptive fields are altered by boundary geometry as early as tested, suggesting this is an inherent feature of the hippocampal representation of space.
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Affiliation(s)
- Laurenz Muessig
- Department of Cell and Developmental Biology, University College London, London, WC1E 6BT, UK
| | | | - Tale L Bjerknes
- Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology, Trondheim, 7491, Norway
| | - Benjamin W Towse
- Institute of Cognitive Neuroscience, University College London, London, WC1N 3AZ, UK
| | - Caswell Barry
- Department of Cell and Developmental Biology, University College London, London, WC1E 6BT, UK
| | - Neil Burgess
- Institute of Cognitive Neuroscience, University College London, London, WC1N 3AZ, UK
- UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Edvard I Moser
- Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology, Trondheim, 7491, Norway
| | - May-Britt Moser
- Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology, Trondheim, 7491, Norway
| | - Francesca Cacucci
- Department of Neuroscience, Physiology and Pharmacology; University College London, London, WC1E 6BT, UK
| | - Thomas J Wills
- Department of Cell and Developmental Biology, University College London, London, WC1E 6BT, UK.
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Affiliation(s)
- Faraneh Vargha-Khadem
- Centre for Developmental Cognitive Neuroscience, UCL Great Ormond Street Institute of Child Health, London, UK; Great Ormond Street Hospital for Children National Health Service Foundation Trust, London, UK.
| | - Francesca Cacucci
- Centre for Developmental Cognitive Neuroscience, UCL Great Ormond Street Institute of Child Health, London, UK; Dept. of Neuroscience, Physiology and Pharmacology, UCL, London, UK
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Muessig L, Lasek M, Varsavsky I, Cacucci F, Wills TJ. Coordinated Emergence of Hippocampal Replay and Theta Sequences during Post-natal Development. Curr Biol 2019; 29:834-840.e4. [PMID: 30773370 PMCID: PMC6408330 DOI: 10.1016/j.cub.2019.01.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 12/30/2018] [Accepted: 01/02/2019] [Indexed: 12/15/2022]
Abstract
Hippocampal place cells encode an animal’s current position in space during exploration [1]. During sleep, hippocampal network activity recapitulates patterns observed during recent experience: place cells with overlapping spatial fields show a greater tendency to co-fire (“reactivation”) [2], and temporally ordered and compressed sequences of place cell firing observed during wakefulness are reinstated (“replay”) [3, 4, 5]. Reactivation and replay may underlie memory consolidation [6, 7, 8, 9, 10]. Compressed sequences of place cell firing also occur during exploration: during each cycle of the theta oscillation, the set of active place cells shifts from those signaling positions behind to those signaling positions ahead of an animal’s current location [11, 12]. These “theta sequences” have been linked to spatial planning [13]. Here, we demonstrate that, before weaning (post-natal day [P]21), offline place cell activity associated with sharp-wave ripples (SWRs) reflects predominantly stationary locations in recently visited environments. By contrast, sequential place cell firing, describing extended trajectories through space during exploration (theta sequences) and subsequent rest (replay), emerge gradually after weaning in a coordinated fashion, possibly due to a progressive decrease in the threshold for experience-driven plasticity. Hippocampus-dependent learning and memory emerge late in altricial mammals [14, 15, 16, 17], appearing around weaning in rats and slowly maturing thereafter [14, 15]. In contrast, spatially localized firing is observed 1 week earlier (with reduced spatial tuning and stability) [18, 19, 20, 21]. By examining the development of hippocampal reactivation, replay, and theta sequences, we show that the coordinated maturation of offline consolidation and online sequence generation parallels the late emergence of hippocampal memory in the rat. Hippocampal activity encoding single places is reactivated during sleep in young rats The threshold for plasticity-driven reactivation is higher during early development Sequential firing linking contiguous places emerges gradually during development Maturation of online and offline sequential activity and memory are coordinated
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Affiliation(s)
- Laurenz Muessig
- Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Michal Lasek
- Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London WC1E 6BT, UK
| | - Isabella Varsavsky
- Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Francesca Cacucci
- Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London WC1E 6BT, UK.
| | - Thomas Joseph Wills
- Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK.
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Medawar E, Benway TA, Liu W, Hanan TA, Haslehurst P, James OT, Yap K, Muessig L, Moroni F, Nahaboo Solim MA, Baidildinova G, Wang R, Richardson JC, Cacucci F, Salih DA, Cummings DM, Edwards FA. Effects of rising amyloidβ levels on hippocampal synaptic transmission, microglial response and cognition in APP Swe/PSEN1 M146V transgenic mice. EBioMedicine 2019; 39:422-435. [PMID: 30555043 PMCID: PMC6354711 DOI: 10.1016/j.ebiom.2018.12.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 12/03/2018] [Accepted: 12/05/2018] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Progression of Alzheimer's disease is thought initially to depend on rising amyloidβ and its synaptic interactions. Transgenic mice (TASTPM; APPSwe/PSEN1M146V) show altered synaptic transmission, compatible with increased physiological function of amyloidβ, before plaques are detected. Recently, the importance of microglia has become apparent in the human disease. Similarly, TASTPM show a close association of plaque load with upregulated microglial genes. METHODS CA1 synaptic transmission and plasticity were investigated using in vitro electrophysiology. Microglial relationship to plaques was examined with immunohistochemistry. Behaviour was assessed with a forced-alternation T-maze, open field, light/dark box and elevated plus maze. FINDINGS The most striking finding is the increase in microglial numbers in TASTPM, which, like synaptic changes, begins before plaques are detected. Further increases and a reactive phenotype occur later, concurrent with development of larger plaques. Long-term potentiation is initially enhanced at pre-plaque stages but decrements with the initial appearance of plaques. Finally, despite altered plasticity, TASTPM have little cognitive deficit, even with a heavy plaque load, although they show altered non-cognitive behaviours. INTERPRETATION The pre-plaque synaptic changes and microglial proliferation are presumably related to low, non-toxic amyloidβ levels in the general neuropil and not directly associated with plaques. However, as plaques grow, microglia proliferate further, clustering around plaques and becoming phagocytic. Like in humans, even when plaque load is heavy, without development of neurofibrillary tangles and neurodegeneration, these alterations do not result in cognitive deficits. Behaviours are seen that could be consistent with pre-diagnosis changes in the human condition. FUNDING GlaxoSmithKline; BBSRC; UCL; ARUK; MRC.
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Affiliation(s)
- Evelyn Medawar
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK..
| | - Tiffanie A Benway
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK..
| | - Wenfei Liu
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK..
| | - Taylor A Hanan
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Peter Haslehurst
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK..
| | - Owain T James
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Kenrick Yap
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Laurenz Muessig
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK..
| | - Fabia Moroni
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Muzammil A Nahaboo Solim
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK.; Institute of Cellular Medicine, Newcastle University Medical School, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK..
| | - Gaukhar Baidildinova
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK.; Department of Science and Innovations, Asfendiyarov Kazakh National Medical University, Zhamakayev Street, Almaty, A26P6B5, Kazakhstan
| | - Rui Wang
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK..
| | - Jill C Richardson
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK..
| | - Francesca Cacucci
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK..
| | - Dervis A Salih
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK..
| | - Damian M Cummings
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK..
| | - Frances A Edwards
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK..
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7
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Chen G, King JA, Lu Y, Cacucci F, Burgess N. Spatial cell firing during virtual navigation of open arenas by head-restrained mice. eLife 2018; 7:34789. [PMID: 29911974 PMCID: PMC6029848 DOI: 10.7554/elife.34789] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 06/11/2018] [Indexed: 12/17/2022] Open
Abstract
We present a mouse virtual reality (VR) system which restrains head-movements to horizontal rotations, compatible with multi-photon imaging. This system allows expression of the spatial navigation and neuronal firing patterns characteristic of real open arenas (R). Comparing VR to R: place and grid, but not head-direction, cell firing had broader spatial tuning; place, but not grid, cell firing was more directional; theta frequency increased less with running speed, whereas increases in firing rates with running speed and place and grid cells' theta phase precession were similar. These results suggest that the omni-directional place cell firing in R may require local-cues unavailable in VR, and that the scale of grid and place cell firing patterns, and theta frequency, reflect translational motion inferred from both virtual (visual and proprioceptive) and real (vestibular translation and extra-maze) cues. By contrast, firing rates and theta phase precession appear to reflect visual and proprioceptive cues alone.
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Affiliation(s)
- Guifen Chen
- UCL Institute of Cognitive Neuroscience, University College London, London, United Kingdom.,Department of Neuroscience Physiology and Pharmacology, University College London, London, United Kingdom
| | - John Andrew King
- Department of Clinical Educational Health Psychology, University College London, London, United Kingdom
| | - Yi Lu
- UCL Institute of Cognitive Neuroscience, University College London, London, United Kingdom.,Department of Neuroscience Physiology and Pharmacology, University College London, London, United Kingdom
| | - Francesca Cacucci
- Department of Neuroscience Physiology and Pharmacology, University College London, London, United Kingdom
| | - Neil Burgess
- UCL Institute of Cognitive Neuroscience, University College London, London, United Kingdom.,UCL Institute of Neurology, University College London, London, United Kingdom
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Korotkova T, Ponomarenko A, Monaghan CK, Poulter SL, Cacucci F, Wills T, Hasselmo ME, Lever C. Reconciling the different faces of hippocampal theta: The role of theta oscillations in cognitive, emotional and innate behaviors. Neurosci Biobehav Rev 2018; 85:65-80. [DOI: 10.1016/j.neubiorev.2017.09.004] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 08/22/2017] [Accepted: 09/02/2017] [Indexed: 12/30/2022]
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9
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Affiliation(s)
- Hui Min Tan
- Singapore Institute for Clinical SciencesSingapore
| | - Thomas Joseph Wills
- Department of Cell and Developmental Biology, Division of BiosciencesUniversity College LondonLondonUK
| | - Francesca Cacucci
- Department of Neuroscience, Physiology and Pharmacology, Division of BiosciencesUniversity College LondonLondonUK
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10
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Tan HM, Wills TJ, Cacucci F. The development of spatial and memory circuits in the rat. WIREs Cogn Sci 2016; 8. [DOI: 10.1002/wcs.1424] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Revised: 09/12/2016] [Accepted: 09/16/2016] [Indexed: 12/19/2022]
Affiliation(s)
- Hui Min Tan
- Singapore Institute for Clinical SciencesSingapore
| | - Thomas Joseph Wills
- Department of Cell and Developmental Biology, Division of BiosciencesUniversity College LondonLondonUK
| | - Francesca Cacucci
- Department of Neuroscience, Physiology and Pharmacology, Division of BiosciencesUniversity College LondonLondonUK
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11
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Marzo A, Galli S, Lopes D, McLeod F, Podpolny M, Segovia-Roldan M, Ciani L, Purro S, Cacucci F, Gibb A, Salinas PC. Reversal of Synapse Degeneration by Restoring Wnt Signaling in the Adult Hippocampus. Curr Biol 2016; 26:2551-2561. [PMID: 27593374 PMCID: PMC5070786 DOI: 10.1016/j.cub.2016.07.024] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 07/05/2016] [Accepted: 07/12/2016] [Indexed: 11/30/2022]
Abstract
Synapse degeneration occurs early in neurodegenerative diseases and correlates strongly with cognitive decline in Alzheimer’s disease (AD). The molecular mechanisms that trigger synapse vulnerability and those that promote synapse regeneration after substantial synaptic failure remain poorly understood. Increasing evidence suggests a link between a deficiency in Wnt signaling and AD. The secreted Wnt antagonist Dickkopf-1 (Dkk1), which is elevated in AD, contributes to amyloid-β-mediated synaptic failure. However, the impact of Dkk1 at the circuit level and the mechanism by which synapses disassemble have not yet been explored. Using a transgenic mouse model that inducibly expresses Dkk1 in the hippocampus, we demonstrate that Dkk1 triggers synapse loss, impairs long-term potentiation, enhances long-term depression, and induces learning and memory deficits. We decipher the mechanism involved in synapse loss induced by Dkk1 as it can be prevented by combined inhibition of the Gsk3 and RhoA-Rock pathways. Notably, after loss of synaptic connectivity, reactivation of the Wnt pathway by cessation of Dkk1 expression completely restores synapse number, synaptic plasticity, and long-term memory. These findings demonstrate the remarkable capacity of adult neurons to regenerate functional circuits and highlight Wnt signaling as a targetable pathway for neuronal circuit recovery after synapse degeneration. Wnt signaling is required for synapse integrity in the adult hippocampus Dkk1 induces synapse loss and deficits in synaptic plasticity and long-term memory Dkk1 disassembles synapses by activating the Gsk3 and Rock pathways Synapse loss and memory defects are reversible by reactivation of the Wnt pathway
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Affiliation(s)
- Aude Marzo
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Soledad Galli
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Douglas Lopes
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Faye McLeod
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Marina Podpolny
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | | | - Lorenza Ciani
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Silvia Purro
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
| | - Francesca Cacucci
- Department of Neuroscience, Physiology, and Pharmacology, University College London, London WC1E 6BT, UK
| | - Alasdair Gibb
- Department of Neuroscience, Physiology, and Pharmacology, University College London, London WC1E 6BT, UK
| | - Patricia C Salinas
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK.
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12
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Chen G, Manson D, Cacucci F, Wills TJ. Absence of Visual Input Results in the Disruption of Grid Cell Firing in the Mouse. Curr Biol 2016; 26:2335-42. [PMID: 27498565 PMCID: PMC5026695 DOI: 10.1016/j.cub.2016.06.043] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 05/30/2016] [Accepted: 06/20/2016] [Indexed: 12/02/2022]
Abstract
Grid cells are spatially modulated neurons within the medial entorhinal cortex whose firing fields are arranged at the vertices of tessellating equilateral triangles [1]. The exquisite periodicity of their firing has led to the suggestion that they represent a path integration signal, tracking the organism’s position by integrating speed and direction of movement [2, 3, 4, 5, 6, 7, 8, 9, 10]. External sensory inputs are required to reset any errors that the path integrator would inevitably accumulate. Here we probe the nature of the external sensory inputs required to sustain grid firing, by recording grid cells as mice explore familiar environments in complete darkness. The absence of visual cues results in a significant disruption of grid cell firing patterns, even when the quality of the directional information provided by head direction cells is largely preserved. Darkness alters the expression of velocity signaling within the entorhinal cortex, with changes evident in grid cell firing rate and the local field potential theta frequency. Short-term (<1.5 s) spike timing relationships between grid cell pairs are preserved in the dark, indicating that network patterns of excitatory and inhibitory coupling between grid cells exist independently of visual input and of spatially periodic firing. However, we find no evidence of preserved hexagonal symmetry in the spatial firing of single grid cells at comparable short timescales. Taken together, these results demonstrate that visual input is required to sustain grid cell periodicity and stability in mice and suggest that grid cells in mice cannot perform accurate path integration in the absence of reliable visual cues. Grid cell firing patterns are disrupted in darkness in the mouse Grid cells are disrupted even when head direction cell signaling is preserved Absence of visual input alters movement velocity modulation of theta frequency Temporal firing relationships between grid cell pairs are preserved in the dark
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Affiliation(s)
- Guifen Chen
- Department of Neuroscience, Physiology, and Pharmacology, UCL, Gower Street, London WC1E 6BT, UK.
| | - Daniel Manson
- Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK; Centre for Mathematics and Physics in the Life Sciences and Experimental Biology, UCL, Gower Place, London WC1E 6BT, UK
| | - Francesca Cacucci
- Department of Neuroscience, Physiology, and Pharmacology, UCL, Gower Street, London WC1E 6BT, UK.
| | - Thomas Joseph Wills
- Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK.
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13
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Muessig L, Hauser J, Wills TJ, Cacucci F. Place Cell Networks in Pre-weanling Rats Show Associative Memory Properties from the Onset of Exploratory Behavior. Cereb Cortex 2016; 26:3627-3636. [PMID: 27282394 PMCID: PMC4961032 DOI: 10.1093/cercor/bhw174] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Place cells are hippocampal pyramidal cells that are active when an animal visits a restricted area of the environment, and collectively their activity constitutes a neural representation of space. Place cell populations in the adult rat hippocampus display fundamental properties consistent with an associative memory network: the ability to 1) generate new and distinct spatial firing patterns when encountering novel spatial contexts or changes in sensory input (“remapping”) and 2) reinstate previously stored firing patterns when encountering a familiar context, including on the basis of an incomplete/degraded set of sensory cues (“pattern completion”). To date, it is unknown when these spatial memory responses emerge during brain development. Here, we show that, from the age of first exploration (postnatal day 16) onwards, place cell populations already exhibit these key features: they generate new representations upon exposure to a novel context and can reactivate familiar representations on the basis of an incomplete set of sensory cues. These results demonstrate that, as early as exploratory behaviors emerge, and despite the absence of an adult-like grid cell network, the developing hippocampus processes incoming sensory information as an associative memory network.
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Affiliation(s)
- L Muessig
- Department of Neuroscience, Physiology and Pharmacology
| | - J Hauser
- Department of Neuroscience, Physiology and Pharmacology
| | - T J Wills
- Department of Cell and Developmental Biology, University College London, London, UK
| | - F Cacucci
- Department of Neuroscience, Physiology and Pharmacology
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14
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Muessig L, Hauser J, Wills TJ, Cacucci F. A Developmental Switch in Place Cell Accuracy Coincides with Grid Cell Maturation. Neuron 2015; 86:1167-73. [PMID: 26050036 PMCID: PMC4460188 DOI: 10.1016/j.neuron.2015.05.011] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 03/10/2015] [Accepted: 04/30/2015] [Indexed: 11/29/2022]
Abstract
Place cell firing relies on information about self-motion and the external environment, which may be conveyed by grid and border cells, respectively. Here, we investigate the possible contributions of these cell types to place cell firing, taking advantage of a developmental time window during which stable border cell, but not grid cell, inputs are available. We find that before weaning, the place cell representation of space is denser, more stable, and more accurate close to environmental boundaries. Boundary-responsive neurons such as border cells may, therefore, contribute to stable and accurate place fields in pre-weanling rats. By contrast, place cells become equally stable and accurate throughout the environment after weaning and in adulthood. This developmental switch in place cell accuracy coincides with the emergence of the grid cell network in the entorhinal cortex, raising the possibility that grid cells contribute to stable place fields when an organism is far from environmental boundaries. During early development, place cell maps are maximally stable near boundaries At weaning age, place cell maps switch to become equally accurate throughout space This developmental switch coincides with the emergence of the grid cell network Boundary cells may support place maps at edges, and grid cells in the environment center
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Affiliation(s)
- Laurenz Muessig
- Department of Neuroscience, Physiology, and Pharmacology, University College London, Gower Street, London WC1E 6BT, UK
| | - Jonas Hauser
- Department of Neuroscience, Physiology, and Pharmacology, University College London, Gower Street, London WC1E 6BT, UK
| | - Thomas Joseph Wills
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK.
| | - Francesca Cacucci
- Department of Neuroscience, Physiology, and Pharmacology, University College London, Gower Street, London WC1E 6BT, UK.
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15
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Abstract
The role of the hippocampal formation in spatial cognition is thought to be supported by distinct classes of neurons whose firing is tuned to an organism's position and orientation in space. In this article, we review recent research focused on how and when this neural representation of space emerges during development: each class of spatially tuned neurons appears at a different age, and matures at a different rate, but all the main spatial responses tested so far are present by three weeks of age in the rat. We also summarize the development of spatial behaviour in the rat, describing how active exploration of space emerges during the third week of life, the first evidence of learning in formal tests of hippocampus-dependent spatial cognition is observed in the fourth week, whereas fully adult-like spatial cognitive abilities require another few weeks to be achieved. We argue that the development of spatially tuned neurons needs to be considered within the context of the development of spatial behaviour in order to achieve an integrated understanding of the emergence of hippocampal function and spatial cognition.
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Affiliation(s)
- Thomas J Wills
- Department of Cell and Developmental Biology, University College London, , London WC1E 6BT, UK
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16
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Wills TJ, Cacucci F. The development of the hippocampal neural representation of space. Curr Opin Neurobiol 2013; 24:111-9. [PMID: 24492087 DOI: 10.1016/j.conb.2013.09.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 09/04/2013] [Accepted: 09/09/2013] [Indexed: 12/21/2022]
Abstract
The hippocampal formation (HF) contains a neural representation of the environment, based on the activity of several classes of neurons whose firing is tuned to an animal's position and orientation in space. Recently, work has begun on understanding when and how this neural map of space emerges during development. Different classes of spatially tuned neurons emerge at different ages, some of them very early during development, before animals have started exploring their environment. The developmental timeline thus far uncovered has yielded insights into both the mechanisms of the ontogeny of the neural code for space, as well as how this system functions in the adult.
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Affiliation(s)
- Thomas J Wills
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK.
| | - Francesca Cacucci
- Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London WC1E 6BT, UK.
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17
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Wills TJ, Barry C, Cacucci F. The abrupt development of adult-like grid cell firing in the medial entorhinal cortex. Front Neural Circuits 2012; 6:21. [PMID: 22557949 PMCID: PMC3338009 DOI: 10.3389/fncir.2012.00021] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Accepted: 04/09/2012] [Indexed: 11/13/2022] Open
Abstract
Understanding the development of the neural circuits subserving specific cognitive functions such as navigation remains a central problem in neuroscience. Here, we characterize the development of grid cells in the medial entorhinal cortex, which, by nature of their regularly spaced firing fields, are thought to provide a distance metric to the hippocampal neural representation of space. Grid cells emerge at the time of weaning in the rat, at around 3 weeks of age. We investigated whether grid cells in young rats are functionally equivalent to those observed in the adult as soon as they appear, or if instead they follow a gradual developmental trajectory. We find that, from the very youngest ages at which reproducible grid firing is observed (postnatal day 19): grid cells display adult-like firing fields that tessellate to form a coherent map of the local environment; that this map is universal, maintaining its internal structure across different environments; and that grid cells in young rats, as in adults, also encode a representation of direction and speed. To further investigate the developmental processes leading up to the appearance of grid cells, we present data from individual medial entorhinal cortex cells recorded across more than 1 day, spanning the period before and after the grid firing pattern emerged. We find that increasing spatial stability of firing was correlated with increasing gridness.
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Affiliation(s)
- Thomas J Wills
- Department of Cell and Developmental Biology, Division of Biosciences, University College London London, UK
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18
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Stewart S, Cacucci F, Lever C. Which Memory Task for My Mouse? A Systematic Review of Spatial Memory Performance in the Tg2576 Alzheimer's Mouse Model. ACTA ACUST UNITED AC 2011; 26:105-26. [DOI: 10.3233/jad-2011-101827] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Sarah Stewart
- Behavioural Neuroscience Lab, Institute of Psychological Sciences, University of Leeds, Leeds, UK
| | - Francesca Cacucci
- Institute of Behavioural Neuroscience, University College London, London, UK
| | - Colin Lever
- Behavioural Neuroscience Lab, Institute of Psychological Sciences, University of Leeds, Leeds, UK
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19
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Abstract
Orienting in large-scale space depends on the interaction of environmental experience and preconfigured, possibly innate, constructs. Place, head-direction, and grid cells in the hippocampal formation provide allocentric representations of space. Here we show how these cognitive representations emerge and develop as rat pups first begin to explore their environment. Directional, locational, and rhythmic organization of firing are present during initial exploration, including adultlike directional firing. The stability and precision of place cell firing continue to develop throughout juvenility. Stable grid cell firing appears later but matures rapidly to adult levels. Our results demonstrate the presence of three neuronal representations of space before extensive experience and show how they develop with age.
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Affiliation(s)
- Tom J Wills
- Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK.
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20
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Lever C, Burton S, Jeewajee A, Wills TJ, Cacucci F, Burgess N, O'Keefe J. Environmental novelty elicits a later theta phase of firing in CA1 but not subiculum. Hippocampus 2010; 20:229-34. [PMID: 19623610 PMCID: PMC3173854 DOI: 10.1002/hipo.20671] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The mechanism supporting the role of the hippocampal formation in novelty detection remains controversial. A comparator function has been variously ascribed to CA1 or subiculum, whereas the theta rhythm has been suggested to separate neural firing into encoding and retrieval phases. We investigated theta phase of firing in principal cells in subiculum and CA1 as rats foraged in familiar and novel environments. We found that the preferred theta phase of firing in CA1, but not subiculum, was shifted to a later phase of the theta cycle during environmental novelty. Furthermore, the amount of phase shift elicited by environmental change correlated with the extent of place cell remapping in CA1. Our results support a relationship between theta phase and novelty-induced plasticity in CA1.
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Affiliation(s)
- Colin Lever
- Behavioural Neuroscience Lab, Institute of Psychological Sciences, University of Leeds, Leeds, United Kingdom.
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21
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Cacucci F, Wills TJ, Lever C, Giese KP, O'Keefe J. Experience-dependent increase in CA1 place cell spatial information, but not spatial reproducibility, is dependent on the autophosphorylation of the alpha-isoform of the calcium/calmodulin-dependent protein kinase II. J Neurosci 2007; 27:7854-9. [PMID: 17634379 PMCID: PMC2680063 DOI: 10.1523/jneurosci.1704-07.2007] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Place cells in hippocampal area CA1 are essential for spatial learning and memory. Here, we examine whether daily exposure to a previously unexplored environment can alter place cell properties. We demonstrate two previously unreported slowly developing plasticities in mouse place fields: both the spatial tuning and the trial-to-trial reproducibility of CA1 place fields improve over days. We asked whether these two components of improved spatial coding rely on the alpha-isoform of the calcium/calmodulin-dependent protein kinase II (alphaCaMKII) autophosphorylation, an effector mechanism of NMDA receptor-dependent long-term potentiation and an essential molecular process for spatial memory formation. We show that, in mice with deficient autophosphorylation of alphaCaMKII, the spatial tuning of place fields is initially similar to that of wild-type mice, but completely fails to show the experience-dependent increase over days. In contrast, place field reproducibility in the mutants, although impaired, does show the experience-dependent increase over days. Consequently, the progressive improvement in spatial coding in new hippocampal place cell maps depends on the existence of two molecularly dissociable, experience-dependent processes.
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Affiliation(s)
- Francesca Cacucci
- Department of Anatomy and Developmental Biology, University College London, London WC1E 6BT, United Kingdom.
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22
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Abstract
We report the spatial and temporal properties of a class of cells termed theta-modulated place-by-direction (TPD) cells recorded from the presubicular and parasubicular cortices of the rat. The firing characteristics of TPD cells in open-field enclosures were compared with those of the following two other well characterized cell classes in the hippocampal formation: place and head-direction cells. Unlike place cells, which code only for the animal's location, or head-direction cells, which code only for the animal's directional heading, TPD cells code for both the location and the head direction of the animal. Their firing is also strongly theta modulated, firing primarily at the negative-to-positive phase of the locally recorded theta wave. TPD theta modulation is significantly stronger than that of place cells. In contrast, the firing of head-direction cells is not modulated by theta at all. In repeated exposures to the same environment, the locational and directional signals of TPD cells are stable. When recorded in different environments, TPD locational and directional fields can uncouple, with the locational field shifting unpredictably ("remapping"), whereas the directional preference remains similar across environments.
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Affiliation(s)
- Francesca Cacucci
- Department of Anatomy and Developmental Biology, University College London, WC1N 3AR, London, United Kingdom.
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23
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Abstract
Memories are thought to be attractor states of neuronal representations, with the hippocampus a likely substrate for context-dependent episodic memories. However, such states have not been directly observed. For example, the hippocampal place cell representation of location was previously found to respond continuously to changes in environmental shape alone. We report that exposure to novel square and circular environments made of different materials creates attractor representations for both shapes: Place cells abruptly and simultaneously switch between representations as environmental shape changes incrementally. This enables study of attractor dynamics in a cognitive representation and may correspond to the formation of distinct contexts in context-dependent memory.
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Affiliation(s)
- Tom J Wills
- Department of Anatomy and Developmental Biology, University College London, London WC1E 6BT, UK
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24
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Abstract
The heterogeneous sampling of behavioral states by freely moving animals hinders our ability to relate neuronal firing rates to behavioral variables by introducing dependencies between them. We specifically consider the animal's location and orientation, although our analyses may generalize to other behavioral variables, such as speed of movement. A maximum-likelihood approach is presented for producing estimates of the separate histograms relating firing rate to multiple independent causes. Examples show that the method can be used to avoid the artifactual behavioral correlates of place and head direction-cell firing produced by standard analyses; to characterize the independent influences of both location and orientation in a third cell type (Cacucci et al., 2004); and to demonstrate the location-independence of the directional firing of head-direction cells.
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Affiliation(s)
- Neil Burgess
- Department of Anatomy and Developmental Biology, University College London, United Kingdom.
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25
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Lever C, Burgess N, Cacucci F, Hartley T, O'Keefe J. What can the hippocampal representation of environmental geometry tell us about Hebbian learning? Biol Cybern 2002; 87:356-372. [PMID: 12461626 DOI: 10.1007/s00422-002-0360-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The importance of the hippocampus in spatial representation is well established. It is suggested that the rodent hippocampal network should provide an optimal substrate for the study of unsupervised Hebbian learning. We focus on the firing characteristics of hippocampal place cells in morphologically different environments. A hard-wired quantitative geometric model of individual place fields is reviewed and presented as the framework in which to understand the additional effects of synaptic plasticity. Existent models employing Hebbian learning are also reviewed. New information is presented regarding the dynamics of place field plasticity over short and long time scales in experiments using barriers and differently shaped walled environments. It is argued that aspects of the temporal dynamics of stability and plasticity in the hippocampal place cell representation both indicate modifications to, and inform the nature of, the synaptic plasticity in place cell models. Our results identify a potential neural basis for long-term incidental learning of environments and provide strong constraints for the way the unsupervised learning in cell assemblies envisaged by Hebb might occur within the hippocampus.
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Affiliation(s)
- Colin Lever
- Department of Anatomy and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK.
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26
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Abstract
The hippocampus is widely believed to be involved in the storage or consolidation of long-term memories. Several reports have shown short-term changes in single hippocampal unit activity during memory and plasticity experiments, but there has been no experimental demonstration of long-term persistent changes in neuronal activity in any region except primary cortical areas. Here we report that, in rats repeatedly exposed to two differently shaped environments, the hippocampal-place-cell representations of those environments gradually and incrementally diverge; this divergence is specific to environmental shape, occurs independently of explicit reward, persists for periods of at least one month, and transfers to new enclosures of the same shape. These results indicate that place cells may be a neural substrate for long-term incidental learning, and demonstrate the long-term stability of an experience-dependent firing pattern in the hippocampal formation.
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Affiliation(s)
- Colin Lever
- Department of Anatomy and Developmental Biology, University College London, WC1E 6BT, UK.
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27
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Abstract
A model of place-cell firing is presented that makes quantitative predictions about specific place cells' spatial receptive fields following changes to the rat's environment. A place cell's firing rate is modeled as a function of the rat's location by the thresholded sum of the firing rates of a number of putative cortical inputs. These inputs are tuned to respond whenever an environmental boundary is at a particular distance and allocentric direction from the rat. The initial behavior of a place cell in any environment is simply determined by its set of inputs and its threshold; learning is not necessary. The model is shown to produce a good fit to the firing of individual place cells, and populations of place cells across environments of differing shape. The cells' behavior can be predicted for novel environments of arbitrary size and shape, or for manipulations such as introducing a barrier. The model can be extended to make behavioral predictions regarding spatial memory.
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Affiliation(s)
- T Hartley
- Institute of Cognitive Neuroscience, University College London, UK.
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28
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Pernas-Alonso R, Schaffner AE, Perrone-Capano C, Orlando A, Morelli F, Hansen CT, Barker JL, Esposito B, Cacucci F, di Porzio U. Early upregulation of medium neurofilament gene expression in developing spinal cord of the wobbler mouse mutant. Brain Res Mol Brain Res 1996; 38:267-75. [PMID: 8793115 DOI: 10.1016/0169-328x(95)00344-r] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Homozygous wobbler mouse mutants develop a progressive paralysis due to spinal motoneuron degeneration. To understand the molecular aspect underlying the genetic defect we have studied the embryonic (from E13) and postnatal expression of the three neurofilament and choline acetyltransferase genes in each member from several wild-type (wt) and wobbler (wr) progenies. There are no variations among wt littermates at all ages studied. In contrast, analyses of neurofilament mRNA reveals a 3-4-fold increase of medium neurofilament (NFM) mRNA in wobbler mice (wr/wr). The pattern of increased NFM mRNA during development, prior to the appearance of the wobbler phenotype, among littermates (from heterozygous carriers) conforms to a mendelian inheritance of a single gene defect 1:2:1 (wr/wr:wr/+:+/+). Light and heavy neurofilament mRNA levels are also increased later in development exclusively in those individuals with high NFM mRNA values indicating that increase of the latter is associated with increase of the light and heavy subunit expression. Also NF proteins are increased. Expression of choline acetyltransferase gene is instead always comparable to normal control. Our study provides novel insights into the nature of the wobbler defect, strengthening the hypothesis that neurofilament accumulation plays a pivotal role in the etiopathogenesis of motoneuron degeneration.
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Affiliation(s)
- R Pernas-Alonso
- International Institute of Genetics and Biophysics, C.N.R., Naples, Italy
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