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Hadi Z, Pondeca Y, Rust HM, Seemungal BM. Electrophysiological markers of vestibular-mediated self-motion perception - A pilot study. Brain Res 2024; 1840:149048. [PMID: 38844198 DOI: 10.1016/j.brainres.2024.149048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 05/22/2024] [Accepted: 05/30/2024] [Indexed: 06/12/2024]
Abstract
Peripheral vestibular activation results in multi-level responses, from brainstem-mediated reflexes (e.g. vestibular ocular reflex - VOR) to perception of self-motion. While VOR responses indicate preserved vestibular peripheral and brainstem functioning, there are no automated measures of vestibular perception of self-motion - important since some patients with brain disconnection syndromes manifest a vestibular agnosia (intact VOR but impaired self-motion perception). Electroencephalography ('EEG') - may provide a surrogate marker of vestibular perception of self-motion. A related objective is obtaining an EEG marker of vestibular sensory signal processing, distinct from vestibular-motion perception. We performed a pilot study comparing EEG responses in the dark when healthy participants sat in a vibrationless computer-controlled motorised rotating chair moving at near threshold of self-motion perception, versus a second situation in which subjects sat in the chair at rest in the dark who could be induced (or not) into falsely perceiving self-motion. In both conditions subjects could perceive self-motion perception, but in the second there was no bottom-up reflex-brainstem activation. Time-frequency analyses showed: (i) alpha frequency band activity is linked to vestibular sensory-signal activation; and (ii) theta band activity is a marker of vestibular-mediated self-motion perception. Consistent with emerging animal data, our findings support the role of theta activity in the processing of self-motion perception.
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Affiliation(s)
- Zaeem Hadi
- Centre for Vestibular Neurology, Department of Brain Sciences, Imperial College London, UK.
| | - Yuscah Pondeca
- Centre for Vestibular Neurology, Department of Brain Sciences, Imperial College London, UK
| | - Heiko M Rust
- Centre for Vestibular Neurology, Department of Brain Sciences, Imperial College London, UK; Department of Neurology, University Hospital Basel, Switzerland
| | - Barry M Seemungal
- Centre for Vestibular Neurology, Department of Brain Sciences, Imperial College London, UK.
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2
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Smith PF. Aging of the vestibular system and its relationship to dementia. Curr Opin Neurol 2024; 37:83-87. [PMID: 38038627 DOI: 10.1097/wco.0000000000001231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2023]
Abstract
PURPOSE OF REVIEW Since October 2022, substantial new information has been published on age-related effects on the vestibular system. Since much of this evidence relates to the risk of dementia, the purpose of this review will be to provide an overview of this new information and critically evaluate it. RECENT FINDINGS This review will address studies published since October 2022 regarding age-related effects on the vestibular system and their relationship to cognition and dementia. There has been a particular increase in the last year in the number of studies relating aging of the vestibular system to Alzheimer's disease (AD), further supporting the view that vestibular dysfunction is associated with an increased risk of dementia. SUMMARY The conclusion of these recent studies is that, consistent with previous studies, vestibular function declines with age, and that this age-related decline is associated with cognitive impairment and an increased risk of dementia. Efforts are being made to consider these implications for cognition in the treatment of vestibular disorders.
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Affiliation(s)
- Paul F Smith
- Department of Pharmacology and Toxicology, School of Biomedical Sciences, and the Brain Health Research Centre, University of Otago, Dunedin
- Eisdell Moore Centre for Hearing and Balance Research, University of Auckland, Auckland, New Zealand
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3
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Smith PF. Interpreting the meaning of changes in hippocampal volume associated with vestibular loss. Front Integr Neurosci 2023; 17:1254972. [PMID: 37608860 PMCID: PMC10440551 DOI: 10.3389/fnint.2023.1254972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 07/21/2023] [Indexed: 08/24/2023] Open
Abstract
Many studies have documented cognitive deficits, especially spatial cognitive deficits, in patients with some form of vestibular loss. Almost 20 years ago, hippocampal (HPC) atrophy was reported to be correlated with spatial memory deficits in such patients and the idea has gradually emerged that HPC atrophy may be causally responsible for the cognitive deficits. However, the results of studies of HPC volume following vestibular loss have not always been consistent, and a number of studies have reported no evidence of HPC atrophy. This paper argues that HPC atrophy, if it does occur following vestibular loss, may not be directly, causally responsible for the cognitive deficits, and that it is more likely that rapid functional changes in the HPC are responsible, due to the interruption of the transmission of vestibular information to the HPC. The argument presented here rests on 3 tranches of evidence: (1) Cognitive deficits have been observed in humans even in the absence of HPC atrophy; (2) HPC atrophy has not been reported in animal studies following vestibular loss, despite cognitive deficits; and (3) Animal studies have shown that the interruption of the transmission of vestibular information to the HPC has immediate consequences for HPC place cells, far too quickly to be explained by HPC atrophy. It is possible that HPC atrophy, when it does occur, is related to the longer-term consquences of living with vestibular loss, which are likely to increase circulating cortisol.
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Affiliation(s)
- Paul F. Smith
- Department of Pharmacology and Toxicology, Brain Health Research Centre, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
- The Brain Research New Zealand Centre of Research Excellence, Eisdell Moore Centre for Hearing and Balance Research, University of Auckland, Auckland, New Zealand
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4
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Jeung S, Hilton C, Berg T, Gehrke L, Gramann K. Virtual Reality for Spatial Navigation. Curr Top Behav Neurosci 2023; 65:103-129. [PMID: 36512288 DOI: 10.1007/7854_2022_403] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Immersive virtual reality (VR) allows its users to experience physical space in a non-physical world. It has developed into a powerful research tool to investigate the neural basis of human spatial navigation as an embodied experience. The task of wayfinding can be carried out by using a wide range of strategies, leading to the recruitment of various sensory modalities and brain areas in real-life scenarios. While traditional desktop-based VR setups primarily focus on vision-based navigation, immersive VR setups, especially mobile variants, can efficiently account for motor processes that constitute locomotion in the physical world, such as head-turning and walking. When used in combination with mobile neuroimaging methods, immersive VR affords a natural mode of locomotion and high immersion in experimental settings, designing an embodied spatial experience. This in turn facilitates ecologically valid investigation of the neural underpinnings of spatial navigation.
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Affiliation(s)
- Sein Jeung
- Department of Biological Psychology and Neuroergonomics, Technische Universität Berlin, Berlin, Germany
- Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway
- Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Christopher Hilton
- Department of Biological Psychology and Neuroergonomics, Technische Universität Berlin, Berlin, Germany
| | - Timotheus Berg
- Department of Biological Psychology and Neuroergonomics, Technische Universität Berlin, Berlin, Germany
| | - Lukas Gehrke
- Department of Biological Psychology and Neuroergonomics, Technische Universität Berlin, Berlin, Germany
| | - Klaus Gramann
- Department of Biological Psychology and Neuroergonomics, Technische Universität Berlin, Berlin, Germany.
- Center for Advanced Neurological Engineering, University of California, San Diego, CA, USA.
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5
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McNaughton N, Vann SD. Construction of complex memories via parallel distributed cortical-subcortical iterative integration. Trends Neurosci 2022; 45:550-562. [PMID: 35599065 PMCID: PMC7612902 DOI: 10.1016/j.tins.2022.04.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 04/01/2022] [Accepted: 04/22/2022] [Indexed: 01/08/2023]
Abstract
The construction of complex engrams requires hippocampal-cortical interactions. These include both direct interactions and ones via often-overlooked subcortical loops. Here, we review the anatomical organization of a hierarchy of parallel 'Papez' loops through the hypothalamus that are homologous in mammals from rats to humans. These hypothalamic loops supplement direct hippocampal-cortical connections with iterative reprocessing paced by theta rhythmicity. We couple existing anatomy and lesion data with theory to propose that recirculation in these loops progressively enhances desired connections, while reducing interference from competing external goals and internal associations. This increases the signal-to-noise ratio in the distributed engrams (neocortical and cerebellar) necessary for complex learning and memory. The hypothalamic nodes provide key motivational input for engram enhancement during consolidation.
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Affiliation(s)
- Neil McNaughton
- Department of Psychology and Brain Health Research Centre, University of Otago, POB56, Dunedin, New Zealand.
| | - Seralynne D Vann
- School of Psychology, Cardiff University, Park Place, Cardiff, CF10 3AT, UK.
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6
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Kennedy JP, Zhou Y, Qin Y, Lovett SD, Sheremet A, Burke SN, Maurer AP. A Direct Comparison of Theta Power and Frequency to Speed and Acceleration. J Neurosci 2022; 42:4326-4341. [PMID: 35477905 PMCID: PMC9145239 DOI: 10.1523/jneurosci.0987-21.2022] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 04/09/2022] [Accepted: 04/14/2022] [Indexed: 11/21/2022] Open
Abstract
Decades of hippocampal neurophysiology research have linked the hippocampal theta rhythm to voluntary movement. A consistent observation has been a robust correlation between the amplitude (or power) and frequency of hippocampal theta and running speed. Recently, however, it has been suggested that acceleration, not running speed, is the dominating influence on theta frequency. There is an inherent interdependence among these two variables, as acceleration is the rate of change in velocity. Therefore, we investigated theta frequency and amplitude of the local-field potential recorded from the stratum pyramidale, stratum radiatum, and stratum lacunosum moleculare of the CA1 subregion, considering both speed and acceleration in tandem as animals traversed a circular task or performed continuous alternation. In male and female rats volitionally controlling their own running characteristics, we found that running speed carries nearly all of the variability in theta frequency and power, with a minute contribution from acceleration. These results contradicted a recent publication using a speed-clamping task, where acceleration and movement are compelled through the use of a bottomless car (Kropff et al., 2021a). Therefore, we reanalyzed the speed-clamping data replicating a transient increase in theta frequency during acceleration. Compared with track running rats, the speed-clamped animals exhibited lower velocities and acceleration values but still showed a stronger influence of speed on theta frequency relative to acceleration. As navigation is the integration of many sensory inputs that are not necessarily linearly related, we offer caution in making absolute claims regarding hippocampal physiology from correlates garnered from a single behavioral repertoire.SIGNIFICANCE STATEMENT A long-standing, replicable observation has been the increase of hippocampal theta power and frequency with increasing running speed. Recently, however, an experimental approach that clamps the running speed of an animal has suggested that acceleration is the dominant influence. Therefore, we analyzed data from freely behaving rats as well as data from the speed-clamping experiment. In unrestrained behavior, speed remains the dominant behavioral correlate to theta amplitude and frequency. Positive acceleration in the speed-clamp experiment induced a transient increase in theta frequency and power. However, speed retained the dominant influence over theta frequency, changing with velocity in both acceleration and deceleration conditions.
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Affiliation(s)
- Jack P Kennedy
- Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida 32610
| | - Yuchen Zhou
- Engineering School of Sustainable Infrastructure & Environment (ESSIE), University of Florida, Gainesville, Florida 32611
| | - Y Qin
- Engineering School of Sustainable Infrastructure & Environment (ESSIE), University of Florida, Gainesville, Florida 32611
| | - Sarah D Lovett
- Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida 32610
| | - A Sheremet
- Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida 32610
- Engineering School of Sustainable Infrastructure & Environment (ESSIE), University of Florida, Gainesville, Florida 32611
| | - S N Burke
- Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida 32610
| | - A P Maurer
- Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida 32610
- Engineering School of Sustainable Infrastructure & Environment (ESSIE), University of Florida, Gainesville, Florida 32611
- Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611
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Chronic, Mild Vestibulopathy Leads to Deficits in Spatial Tasks that Rely on Vestibular Input While Leaving Other Cognitive Functions and Brain Volumes Intact. Life (Basel) 2021; 11:life11121369. [PMID: 34947900 PMCID: PMC8707705 DOI: 10.3390/life11121369] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 11/30/2021] [Accepted: 12/07/2021] [Indexed: 02/07/2023] Open
Abstract
Objectives: In this study, based on the known vestibulo-hippocampal connections, we asked whether mild chronic vestibulopathy leads only to vestibular-related deficits or whether there are effects on hippocampal function, structure, and cognition in general. In more detail, we assessed whether chronic vestibulopathy leads to (a) deficits in vestibular tasks without cognitive demand (balancing), (b) deficits in spatial cognitive tasks that require vestibular input (path integration, rotational memory), (c) deficits in spatial cognitive tasks that do not rely on vestibular input, (d) deficits in general cognitive function, and (e) atrophy in the brain. Methods: A total of 15 patients with chronic uni- or bilateral vestibulopathy (56.8 ± 10.1 years; 4 females) were included in this study and were age- and gender-matched by the control participants (57.6 ± 10.5) in a pairwise manner. Given their clinical symptoms and their deficits of the vestibulo-ocular reflex (VOR) the patients could be classified as being mildly affected. All participants of the underwent the following tests: clinical balance (CBT), triangle completion (TCT) for path integration, rotational memory (RM), the visuo-spatial subset of the Berlin intelligence structure test (BIS-4) and d2-R for attention and concentration, and a structural MRI for gray matter analysis using voxel-based morphometry (VBM). Results: Compared to the healthy controls, the vestibulopathy patients performed significantly worse in terms of CBT, TCT, and RM but showed no differences in terms of the BIS-4 and d2-R. There were also no significant volumetric gray matter differences between the two groups. Conclusions: This study provides evidence that both non-cognitive and cognitive functions that rely on vestibular input (balancing, path integration, rotational memory) are impaired, even in mild chronic vestibulopathy, while other cognitive functions, which rely on visual input (visuo-spatial memory, attention), are unimpaired in this condition, together with an overall intact brain structure. These findings may reflect a segregation between vestibular- and visual-dependent processes in the medial temporal lobe on the one hand and a structure–function dissociation on the other.
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8
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Banovetz MT, I Lake R, Blackwell AA, Oltmanns JRO, Schaeffer EA, M Yoder R, Wallace DG. Effects of acquired vestibular pathology on the organization of mouse exploratory behavior. Exp Brain Res 2021; 239:1125-1139. [PMID: 33555382 DOI: 10.1007/s00221-020-06032-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 12/30/2020] [Indexed: 11/24/2022]
Abstract
Rodent open field behavior is highly organized and occurs spontaneously in novel environments. This organization is disrupted in mice with vestibular pathology, suggesting vestibular signals provide important contributions to this behavior. A caveat to this interpretation is that previous studies have investigated open field behavior in adult mice with congenital vestibular dysfunction, and the observed deficits may have resulted from developmental changes instead of the lack of vestibular signals. To determine which aspects of open field behavior depend specifically on vestibular signals, mouse movement organization was examined under dark and light conditions at two time points, 1 and 2 months, after bilateral chemical labyrinthectomy. Our results show that acquired vestibular damage selectively disrupted the organization of open field behavior. Access to visual environmental cues attenuated, but did not eliminate, these significant group differences. Improvement in movement organization from the first to the second testing session was limited to progression path circuity. These observations provide evidence for the role of the vestibular system in maintaining spatial orientation and establishes a foundation to investigate neuroplasticity in brain systems that process self-movement information.
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Affiliation(s)
- Mark T Banovetz
- Department of Psychology, Northern Illinois University, DeKalb, 60115, USA
| | - Rami I Lake
- Department of Psychology, Northern Illinois University, DeKalb, 60115, USA
| | - Ashley A Blackwell
- Department of Psychology, Northern Illinois University, DeKalb, 60115, USA
| | | | - Ericka A Schaeffer
- Department of Psychology, Northern Illinois University, DeKalb, 60115, USA
| | - Ryan M Yoder
- Department of Psychology, Coastal Carolina University, Conway, 29528, USA
| | - Douglas G Wallace
- Department of Psychology, Northern Illinois University, DeKalb, 60115, USA.
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9
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Diamanti EM, Reddy CB, Schröder S, Muzzu T, Harris KD, Saleem AB, Carandini M. Spatial modulation of visual responses arises in cortex with active navigation. eLife 2021; 10:e63705. [PMID: 33538692 PMCID: PMC7861612 DOI: 10.7554/elife.63705] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 01/12/2021] [Indexed: 01/01/2023] Open
Abstract
During navigation, the visual responses of neurons in mouse primary visual cortex (V1) are modulated by the animal's spatial position. Here we show that this spatial modulation is similarly present across multiple higher visual areas but negligible in the main thalamic pathway into V1. Similar to hippocampus, spatial modulation in visual cortex strengthens with experience and with active behavior. Active navigation in a familiar environment, therefore, enhances the spatial modulation of visual signals starting in the cortex.
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Affiliation(s)
- E Mika Diamanti
- UCL Institute of Ophthalmology, University College LondonLondonUnited Kingdom
- CoMPLEX, Department of Computer Science, University College LondonLondonUnited Kingdom
| | - Charu Bai Reddy
- UCL Institute of Ophthalmology, University College LondonLondonUnited Kingdom
| | - Sylvia Schröder
- UCL Institute of Ophthalmology, University College LondonLondonUnited Kingdom
| | - Tomaso Muzzu
- UCL Institute of Behavioural Neuroscience, University College LondonLondonUnited Kingdom
| | - Kenneth D Harris
- UCL Queen Square Institute of Neurology, University College LondonLondonUnited Kingdom
| | - Aman B Saleem
- UCL Institute of Behavioural Neuroscience, University College LondonLondonUnited Kingdom
| | - Matteo Carandini
- UCL Institute of Ophthalmology, University College LondonLondonUnited Kingdom
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Hitier M, Zhang YF, Sato G, Besnard S, Zheng Y, Smith PF. Stratification of hippocampal electrophysiological activation evoked by selective electrical stimulation of different angular and linear acceleration sensors in the rat peripheral vestibular system. Hear Res 2021; 403:108173. [PMID: 33465547 DOI: 10.1016/j.heares.2021.108173] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 12/28/2020] [Accepted: 01/05/2021] [Indexed: 01/11/2023]
Abstract
It has become well established that vestibular information is important for hippocampal function and spatial memory. However, as yet, relatively little is known about how different kinds of vestibular information are 'represented' in different parts of the hippocampus. This study used selective electrical stimulation of each of the 5 vestibular sensors (the horizontal (HC), anterior (AC) and posterior (PC) semi-circular canals, and the utricle and saccule) in the rat and recorded local field potentials (LFPs) across the hippocampus, using a 16 electrode microarray. We found that stimulation of any vestibular sensor in the left labyrinth evoked triphasic LFPs in both hippocampi, although it was clear that, in general, the amplitudes were greater for the right, contralateral side. This was particularly true for Phase 1 for the HC, AC, utricle and saccule, Phase 2 for the HC, PC, utricle and saccule, and Phase 3 for the AC, PC and saccule. Overall, our results suggest that vestibular input to the hippocampus is bilateral, preferentially contralateral, but highly stratified in that stimulation of the same vestibular sensor results in activation of different specific areas of the hippocampus, with different LFP amplitudes and latencies. This suggests the possibility that different regions of the hippocampus use different kinds of vestibular information for different purposes and that there may be a high degree of redundancy in the representation of vestibular input, perhaps ensuring that the hippocampus is more robust to the partial loss of vestibular information.
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Affiliation(s)
- Martin Hitier
- Department of Otolaryngology Head and Neck Surgery, CHU de Caen, France; Dept. Anatomy, UNICAEN, Normadie University, 14032 Caen, France; INSERM, U1075, COMETE, 1400, Caen, France; Dept. of Pharmacology and Toxicology, School of Biomedical Sciences and Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Yan-Feng Zhang
- Dept. of Pharmacology and Toxicology, School of Biomedical Sciences and Brain Health Research Centre, University of Otago, Dunedin, New Zealand; Dept. Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Go Sato
- Dept. of Pharmacology and Toxicology, School of Biomedical Sciences and Brain Health Research Centre, University of Otago, Dunedin, New Zealand; Department of Otolaryngology, University of Tokushima School of Medicine, Tokushima, Japan
| | | | - Yiwen Zheng
- Dept. of Pharmacology and Toxicology, School of Biomedical Sciences and Brain Health Research Centre, University of Otago, Dunedin, New Zealand; Brain Research New Zealand Centre of Research Excellence, New Zealand; Eisdell Moore Centre for Hearing and Balance Research, University of Auckland, New Zealand
| | - Paul F Smith
- Dept. of Pharmacology and Toxicology, School of Biomedical Sciences and Brain Health Research Centre, University of Otago, Dunedin, New Zealand; Brain Research New Zealand Centre of Research Excellence, New Zealand; Eisdell Moore Centre for Hearing and Balance Research, University of Auckland, New Zealand.
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11
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Munn RGK, Giocomo LM. Multiple head direction signals within entorhinal cortex: origin and function. Curr Opin Neurobiol 2020; 64:32-40. [DOI: 10.1016/j.conb.2020.01.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 01/23/2020] [Accepted: 01/26/2020] [Indexed: 12/24/2022]
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12
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Smith PF, Truchet B, Chaillan FA, Zheng Y, Besnard S. Vestibular Modulation of Long-Term Potentiation and NMDA Receptor Expression in the Hippocampus. Front Mol Neurosci 2020; 13:140. [PMID: 32848601 PMCID: PMC7431471 DOI: 10.3389/fnmol.2020.00140] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 07/09/2020] [Indexed: 01/01/2023] Open
Abstract
Loss of vestibular function is known to cause spatial memory deficits and hippocampal dysfunction, in terms of impaired place cell firing and abnormal theta rhythm. Based on these results, it has been of interest to determine whether vestibular loss also affects the development and maintenance of long-term potentiation (LTP) in the hippocampus. This article summarizes and critically reviews the studies of hippocampal LTP following a vestibular loss and its relationship to NMDA receptor expression, that have been published to date. Although the available in vitro studies indicate that unilateral vestibular loss (UVL) results in reduced hippocampal field potentials in CA1 and the dentate gyrus (DG), the in vivo studies involving bilateral vestibular loss (BVL) do not. This may be due to the differences between UVL and BVL or it could be a result of in vitro/in vivo differences. One in vitro study reported a decrease in LTP in hippocampal slices following UVL; however, the two available in vivo studies have reported different results: either no effect or an increase in EPSP/Population Spike (ES) potentiation. This discrepancy may be due to the different high-frequency stimulation (HFS) paradigms used to induce LTP. The increased ES potentiation following BVL may be related to an increase in synaptic NMDA receptors, possibly increasing the flow of vestibular input coming into CA1, with a loss of selectivity. This might cause increased excitability and synaptic noise, which might lead to a degradation of spatial learning and memory.
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Affiliation(s)
- Paul F. Smith
- Department of Pharmacology and Toxicology, School of Biomedical Sciences, Brain Health Research Centre, University of Otago, Dunedin, New Zealand
- Brain Research New Zealand, The Eisdell Moore Centre for Hearing and Balance Research, University of Auckland, Auckland, >New Zealand
| | - Bruno Truchet
- Aix Marseille University, CNRS, LNC UMR 7291, FR 3C FR 3512, Marseille, France
| | - Franck A. Chaillan
- Aix Marseille University, CNRS, LNC UMR 7291, FR 3C FR 3512, Marseille, France
| | - Yiwen Zheng
- Department of Pharmacology and Toxicology, School of Biomedical Sciences, Brain Health Research Centre, University of Otago, Dunedin, New Zealand
- Brain Research New Zealand, The Eisdell Moore Centre for Hearing and Balance Research, University of Auckland, Auckland, >New Zealand
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13
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Jacob A, Tward DJ, Resnick S, Smith PF, Lopez C, Rebello E, Wei EX, Ratnanather JT, Agrawal Y. Vestibular function and cortical and sub-cortical alterations in an aging population. Heliyon 2020; 6:e04728. [PMID: 32904672 PMCID: PMC7457317 DOI: 10.1016/j.heliyon.2020.e04728] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 10/10/2019] [Accepted: 08/12/2020] [Indexed: 01/26/2023] Open
Abstract
While it is well known that the vestibular system is responsible for maintaining balance, posture and coordination, there is increasing evidence that it also plays an important role in cognition. Moreover, a growing number of epidemiological studies are demonstrating a link between vestibular dysfunction and cognitive deficits in older adults; however, the exact pathways through which vestibular loss may affect cognition are unknown. In this cross-sectional study, we sought to identify relationships between vestibular function and variation in morphometry in brain structures from structural neuroimaging. We used a subset of 80 participants from the Baltimore Longitudinal Study of Aging, who had both brain MRI and vestibular physiological data acquired during the same visit. Vestibular function was evaluated through the cervical vestibular-evoked myogenic potential (cVEMP). The brain structures of interest that we analyzed were the hippocampus, amygdala, thalamus, caudate nucleus, putamen, insula, entorhinal cortex (ERC), trans-entorhinal cortex (TEC) and perirhinal cortex, as these structures comprise or are connected with the putative "vestibular cortex." We modeled the volume and shape of these structures as a function of the presence/absence of cVEMP and the cVEMP amplitude, adjusting for age and sex. We observed reduced overall volumes of the hippocampus and the ERC associated with poorer vestibular function. In addition, we also found significant relationships between the shape of the hippocampus (p = 0.0008), amygdala (p = 0.01), thalamus (p = 0.008), caudate nucleus (p = 0.002), putamen (p = 0.02), and ERC-TEC complex (p = 0.008) and vestibular function. These findings provide novel insight into the multiple pathways through which vestibular loss may impact brain structures that are critically involved in spatial memory, navigation and orientation.
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Affiliation(s)
- Athira Jacob
- Center for Imaging Science and Institute for Computational Medicine,
Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD,
USA
| | - Daniel J. Tward
- Center for Imaging Science and Institute for Computational Medicine,
Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD,
USA
| | - Susan Resnick
- Laboratory of Behavioral Neuroscience, National Institute on Aging,
Baltimore, MD, USA
| | - Paul F. Smith
- Department Pharmacology and Toxicology, School of Medical Sciences, The
Brain Health Research Centre, University of Otago, New Zealand
| | - Christophe Lopez
- Aix Marseille Universite, Centre National de la Recherche Scientifique,
Marseille, France
| | - Elliott Rebello
- Department of Otolaryngology–Head and Neck Surgery, Johns Hopkins
University School of Medicine, Baltimore, MD, USA
| | - Eric X. Wei
- Department of Otolaryngology–Head and Neck Surgery, Johns Hopkins
University School of Medicine, Baltimore, MD, USA
| | - J. Tilak Ratnanather
- Center for Imaging Science and Institute for Computational Medicine,
Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD,
USA
| | - Yuri Agrawal
- Department of Otolaryngology–Head and Neck Surgery, Johns Hopkins
University School of Medicine, Baltimore, MD, USA
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14
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Sheeran WM, Ahmed OJ. The neural circuitry supporting successful spatial navigation despite variable movement speeds. Neurosci Biobehav Rev 2019; 108:821-833. [PMID: 31760048 DOI: 10.1016/j.neubiorev.2019.11.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 09/30/2019] [Accepted: 11/18/2019] [Indexed: 12/18/2022]
Abstract
Ants who have successfully navigated the long distance between their foraging spot and their nest dozens of times will drastically overshoot their destination if the size of their legs is doubled by the addition of stilts. This observation reflects a navigational strategy called path integration, a strategy also utilized by mammals. Path integration necessitates that animals keep track of their movement speed and use it to precisely and instantly modify where they think they are and where they want to go. Here we review the neural circuitry that has evolved to integrate speed and space. We start with the rate and temporal codes for speed in the hippocampus and work backwards towards the motor and sensory systems. We highlight the need for experiments designed to differentiate the respective contributions of motor efference copy versus sensory inputs. In particular, we discuss the importance of high-resolution tracking of the latency of speed-encoding as a precise way to disentangle the sensory versus motor computations that enable successful spatial navigation at very different speeds.
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Affiliation(s)
- William M Sheeran
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA; Department of Molecular, Cellular & Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Omar J Ahmed
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA; Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA; Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA; Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI 48109, USA; Michigan Center for Integrative Research in Critical Care, University of Michigan, Ann Arbor, MI 48109, USA.
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15
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Smith PF. The Growing Evidence for the Importance of the Otoliths in Spatial Memory. Front Neural Circuits 2019; 13:66. [PMID: 31680880 PMCID: PMC6813194 DOI: 10.3389/fncir.2019.00066] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 09/30/2019] [Indexed: 01/14/2023] Open
Abstract
Many studies have demonstrated that vestibular sensory input is important for spatial learning and memory. However, it has been unclear what contributions the different parts of the vestibular system - the semi-circular canals and otoliths - make to these processes. The advent of mutant otolith-deficient mice has made it possible to isolate the relative contributions of the otoliths, the utricle and saccule. A number of studies have now indicated that the loss of otolithic function impairs normal spatial memory and also impairs the normal function of head direction cells in the thalamus and place cells in the hippocampus. Epidemiological studies have also provided evidence that spatial memory impairment with aging, may be linked to saccular function. The otoliths may be important in spatial cognition because of their evolutionary age as a sensory detector of orientation and the fact that velocity storage is important to the way that the brain encodes its place in space.
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Affiliation(s)
- Paul F. Smith
- Department of Pharmacology and Toxicology, Brain Health Research Centre, School of Biomedical Sciences, University of Otago Medical School, Dunedin, New Zealand
- Brain Research New Zealand, Auckland, New Zealand
- Eisdell Moore Centre for Hearing and Balance Research, University of Auckland, Auckland, New Zealand
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16
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Vestibular rehabilitation in older adults with and without mild cognitive impairment: Effects of virtual reality using a head-mounted display. Arch Gerontol Geriatr 2019; 83:246-256. [DOI: 10.1016/j.archger.2019.05.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 04/23/2019] [Accepted: 05/09/2019] [Indexed: 11/21/2022]
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17
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Noisy galvanic vestibular stimulation modulates spatial memory in young healthy adults. Sci Rep 2019; 9:9310. [PMID: 31249334 PMCID: PMC6597709 DOI: 10.1038/s41598-019-45757-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 06/14/2019] [Indexed: 02/07/2023] Open
Abstract
Hippocampal and striatal circuits play important roles in spatial navigation. These regions integrate environmental information and receive intrinsic afferent inputs from the vestibular system. Past research indicates that galvanic vestibular stimulation (GVS) is a non-invasive technique that modulates hippocampal and striatal activities. There are also evidences for enhanced motor and cognitive functions through GVS. This study extends previous research to investigate whether noisy GVS may improve hippocampal- and striatal-associated aspects of spatial navigation performance. Using a virtual navigation task, we examined effects of noisy GVS on spatial learning and memory. To probe the participants’ sensitivity to hippocampal- or striatal-associated spatial information, we either enlarged the virtual environment’s boundary or replaced an intra-environmental location cue, respectively. Noisy GVS or sham stimulation was applied online during the learning phase in a within-subject crossover design. The results showed that noisy GVS enhanced spatial learning and the sensitivity foremost to hippocampal-dependent spatial information both in males and females. Individual differences in spatial working memory capacity moderated the effects of GVS, with individuals with lower capacity benefitting more from the stimulation. Furthermore, sex-related differences in GVS effects on the two forms of spatial representations may reflect differences between males and females in preferred spatial strategies.
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18
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Differential influences of environment and self-motion on place and grid cell firing. Nat Commun 2019; 10:630. [PMID: 30733457 PMCID: PMC6367320 DOI: 10.1038/s41467-019-08550-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 01/12/2019] [Indexed: 01/15/2023] Open
Abstract
Place and grid cells in the hippocampal formation provide foundational representations of environmental location, and potentially of locations within conceptual spaces. Some accounts predict that environmental sensory information and self-motion are encoded in complementary representations, while other models suggest that both features combine to produce a single coherent representation. Here, we use virtual reality to dissociate visual environmental from physical motion inputs, while recording place and grid cells in mice navigating virtual open arenas. Place cell firing patterns predominantly reflect visual inputs, while grid cell activity reflects a greater influence of physical motion. Thus, even when recorded simultaneously, place and grid cell firing patterns differentially reflect environmental information (or 'states') and physical self-motion (or 'transitions'), and need not be mutually coherent.
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19
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Wei EX, Oh ES, Harun A, Ehrenburg M, Xue QL, Simonsick E, Agrawal Y. Increased Prevalence of Vestibular Loss in Mild Cognitive Impairment and Alzheimer's Disease. Curr Alzheimer Res 2019; 16:1143-1150. [PMID: 31418661 PMCID: PMC10696591 DOI: 10.2174/1567205016666190816114838] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 04/29/2019] [Accepted: 05/17/2019] [Indexed: 01/20/2023]
Abstract
BACKGROUND/AIMS Recent evidence has shown that Alzheimer's Disease (AD) patients have reduced vestibular function relative to healthy controls. In this study, we evaluated whether patients with Mild Cognitive Impairment (MCI) also have reduced vestibular function relative to controls, and compared the level of vestibular impairment between MCI and AD patients. METHODS Vestibular physiologic function was assessed in 77 patients (26 MCI, 51 AD) and 295 matched controls using 3 clinical vestibular tests. The association between vestibular loss and cognitive impairment was evaluated using conditional logistic regression models. RESULTS Individuals with vestibular impairment had a 3 to 4-fold increased odds of being in the MCI vs. control group (p-values < 0.05). MCI patients had a level of vestibular impairment that was intermediate between controls and AD. CONCLUSION These findings suggest a dose-response relationship between vestibular loss and cognitive status, and support the hypothesis that vestibular loss contributes to cognitive decline.
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Affiliation(s)
- Eric X. Wei
- Department of Otolaryngology, Head and Neck Surgery, Johns Hopkins University, School of Medicine, 601 N. Caroline Street, Baltimore, MD 21287, USA
| | - Esther S. Oh
- Department of Medicine, Johns Hopkins University, School of Medicine, 5200 Eastern Ave, Seventh Floor, Baltimore, MD 21224, USA
| | - Aisha Harun
- Department of Otolaryngology, Head and Neck Surgery, Johns Hopkins University, School of Medicine, 601 N. Caroline Street, Baltimore, MD 21287, USA
| | - Matthew Ehrenburg
- Department of Otolaryngology, Head and Neck Surgery, Johns Hopkins University, School of Medicine, 601 N. Caroline Street, Baltimore, MD 21287, USA
| | - Qian-Li Xue
- Division of Geriatric Medicine and Gerontology, Department of Medicine, Johns Hopkins University, School of Medicine, 2024 E. Monument Street, Suite 2-722, Baltimore, MD 21205, USA
| | - Eleanor Simonsick
- National Institute on Aging, National Institutes of Health, 3001 S. Hanover Street, 5th Floor, Baltimore, MD 21225, USA
| | - Yuri Agrawal
- Department of Otolaryngology, Head and Neck Surgery, Johns Hopkins University, School of Medicine, 601 N. Caroline Street, Baltimore, MD 21287, USA
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20
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Micarelli A, Viziano A, Bruno E, Micarelli E, Augimeri I, Alessandrini M. Gradient impact of cognitive decline in unilateral vestibular hypofunction after rehabilitation: preliminary findings. Eur Arch Otorhinolaryngol 2018; 275:2457-2465. [DOI: 10.1007/s00405-018-5109-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 08/27/2018] [Indexed: 11/29/2022]
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21
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Starrett MJ, Ekstrom AD. Perspective: Assessing the Flexible Acquisition, Integration, and Deployment of Human Spatial Representations and Information. Front Hum Neurosci 2018; 12:281. [PMID: 30050422 PMCID: PMC6050378 DOI: 10.3389/fnhum.2018.00281] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 06/22/2018] [Indexed: 12/29/2022] Open
Abstract
Studying human spatial navigation in the lab can be challenging, particularly when including non-invasive neural measures like functional magnetic resonance imaging (fMRI) and scalp encephalography (EEG). While there is broad consensus that human spatial navigation involves both egocentric (self-referenced) and allocentric (world-referenced) coding schemes, exactly how these can be measured in ecologically meaningful situations remains controversial. Here, we explore these two forms of representation and how we might better measure them by reviewing commonly used spatial memory tasks and proposing a new task: the relative vector discrimination (RVD) task. Additionally, we explore how different encoding modalities (desktop virtual reality, immersive virtual reality, maps, and real-world navigation) might alter how egocentric and allocentric representations manifest. Specifically, we discuss desktop virtual reality vs. more immersive forms of navigation that better approximate real-world situations, and the extent to which less immersive encoding modalities alter neural and cognitive codes engaged during navigation more generally. We conclude that while encoding modality likely alters navigation-related codes to some degree, including egocentric and allocentric representations, it does not fundamentally change the underlying representations. Considering these arguments together, we suggest that tools to study human navigation in the lab, such as desktop virtual reality, provide overall a reasonable approximation of in vivo navigation, with some caveats.
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Affiliation(s)
- Michael J Starrett
- Department of Psychology, University of Arizona, Tucson, AZ, United States.,Department of Psychology, University of California, Davis, Davis, CA, United States.,Center for Neuroscience, University of California, Davis, Davis, CA, United States
| | - Arne D Ekstrom
- Department of Psychology, University of Arizona, Tucson, AZ, United States.,Department of Psychology, University of California, Davis, Davis, CA, United States.,Center for Neuroscience, University of California, Davis, Davis, CA, United States.,Neuroscience Graduate Group, University of California, Davis, Davis, CA, United States
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22
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Kamil RJ, Jacob A, Ratnanather JT, Resnick SM, Agrawal Y. Vestibular Function and Hippocampal Volume in the Baltimore Longitudinal Study of Aging (BLSA). Otol Neurotol 2018; 39:765-771. [PMID: 29889787 PMCID: PMC5999049 DOI: 10.1097/mao.0000000000001838] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
OBJECTIVE This study evaluated whether reduced vestibular function in aging adults is associated with lower hippocampal volume. STUDY DESIGN Cross-sectional study. SETTING Baltimore Longitudinal Study of Aging, a long-running longitudinal cohort study of healthy aging. PATIENTS Eligible participants were aged ≥ 60 years and had both vestibular physiological testing and brain magnetic resonance imaging at the same visit. INTERVENTION Vestibular function testing consisted of the cervical vestibular-evoked myogenic potential (cVEMP) to assess saccular function, ocular VEMP to assess utricular function, and video head-impulse testing to assess the horizontal semicircular canal vestibulo-ocular reflex. MAIN OUTCOME MEASURE Hippocampal volume calculated using diffeomorphometry. RESULTS The study sample included 103 participants (range of 35-90 participants in subanalyses) with mean (±SD) age 77.2 years (±8.71). Multivariate linear models including age, intracranial volume, sex, and race showed that 1 μV amplitude increase of cVEMP was associated with an increase of 319.1 mm (p = 0.003) in mean hippocampal volume. We did not observe a significant relationship between ocular VEMP amplitude or vestibulo-ocular reflex gain and mean hippocampal volume. CONCLUSIONS Lower cVEMP amplitude (i.e., reduced saccular function) was significantly associated with lower mean hippocampal volume. This is in line with previous work demonstrating a link between saccular function and spatial cognition. Hippocampal atrophy may be a mechanism by which vestibular loss contributes to impaired spatial cognition in older adults. Future work using longitudinal data will be needed to evaluate the causal nature of the association between vestibular loss and hippocampal atrophy.
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Affiliation(s)
- Rebecca J. Kamil
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University, Baltimore, MD
| | - Athira Jacob
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD
| | | | - Susan M. Resnick
- Laboratory of Behavioral Neuroscience, National Institute on Aging, Baltimore MD
| | - Yuri Agrawal
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University, Baltimore, MD
- Department of Otolaryngology-Head and Neck Surgery, Division of Otology, Neurotology, and Skull Base Surgery, Johns Hopkins University, Baltimore, MD
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23
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Benoit A, Besnard S, Guillamin M, Philoxene B, Sola B, Le Gall A, Machado ML, Toulouse J, Hitier M, Smith PF. Differential regulation of NMDA receptor-expressing neurons in the rat hippocampus and striatum following bilateral vestibular loss demonstrated using flow cytometry. Neurosci Lett 2018; 683:43-47. [PMID: 29936267 DOI: 10.1016/j.neulet.2018.06.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 06/18/2018] [Accepted: 06/20/2018] [Indexed: 01/01/2023]
Abstract
There is substantial evidence that loss of vestibular function impairs spatial learning and memory related to hippocampal (HPC) function, as well as increasing evidence that striatal (Str) plasticity is also implicated. Since the N-methyl-d-aspartate (NMDA) subtype of glutamate receptor is considered essential to spatial memory, previous studies have investigated whether the expression of HPC NMDA receptors changes following vestibular loss; however, the results have been contradictory. Here we used a novel flow cytometric method to quantify the number of neurons expressing NMDA receptors in the HPC and Str following bilateral vestibular loss (BVL) in rats. At 7 and 30 days post-op., there was a significant increase in the number of HPC neurons expressing NMDA receptors in the BVL animals, compared to sham controls (P ≤ 0.004 and P ≤ 0.0001, respectively). By contrast, in the Str, at 7 days there was a significant reduction in the number of neurons expressing NMDA receptors in the BVL group (P ≤ 0.05); however, this difference had disappeared by 30 days post-op. These results suggest that BVL causes differential changes in the number of neurons expressing NMDA receptors in the HPC and Str, which may be related to its long-term impairment of spatial memory.
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Affiliation(s)
- Alice Benoit
- Normandie Univ, Inserm, CHU Caen, COMETE U1075, 14000, Caen, France
| | - Stephane Besnard
- Normandie Univ, Inserm, CHU Caen, COMETE U1075, 14000, Caen, France
| | - Maryline Guillamin
- Normandie Univ, Inserm, CHU Caen, COMETE U1075, 14000, Caen, France; University Normandie, IFR ICORE, Caen, 14032, France
| | - Bruno Philoxene
- Normandie Univ, Inserm, CHU Caen, COMETE U1075, 14000, Caen, France
| | | | - Anne Le Gall
- Normandie Univ, Inserm, CHU Caen, COMETE U1075, 14000, Caen, France
| | | | - Joseph Toulouse
- Normandie Univ, Inserm, CHU Caen, COMETE U1075, 14000, Caen, France
| | - Martin Hitier
- Normandie Univ, Inserm, CHU Caen, COMETE U1075, 14000, Caen, France
| | - Paul F Smith
- Dept. of Pharmacology and Toxicology, School of Biomedical Sciences, and the Brain Health Research Centre, University of Otago, Dunedin, New Zealand; Brain Research New Zealand, Centre of Research Excellence, New Zealand; The Eisdell Moore Centre, University of Auckland, New Zealand.
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24
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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] [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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25
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Degree of Functional Impairment Associated With Vestibular Hypofunction Among Older Adults With Cognitive Decline. Otol Neurotol 2018; 39:e392-e400. [DOI: 10.1097/mao.0000000000001746] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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26
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Effects of electrical stimulation of the rat vestibular labyrinth on c-Fos expression in the hippocampus. Neurosci Lett 2018; 677:60-64. [DOI: 10.1016/j.neulet.2018.04.041] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 04/16/2018] [Accepted: 04/21/2018] [Indexed: 11/18/2022]
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27
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Aitken P, Zheng Y, Smith PF. The modulation of hippocampal theta rhythm by the vestibular system. J Neurophysiol 2018; 119:548-562. [DOI: 10.1152/jn.00548.2017] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The vestibular system is a sensory system that has evolved over millions of years to detect acceleration of the head, both rotational and translational, in three dimensions. One of its most important functions is to stabilize gaze during unexpected head movement; however, it is also important in the control of posture and autonomic reflexes. Theta rhythm is a 3- to 12-Hz oscillating EEG signal that is intimately linked to self-motion and is also known to be important in learning and memory. Many studies over the last two decades have shown that selective activation of the vestibular system, using either natural rotational or translational stimulation, or electrical stimulation of the peripheral vestibular system, can induce and modulate theta activity. Furthermore, inactivation of the vestibular system has been shown to significantly reduce theta in freely moving animals, which may be linked to its impairment of place cell function as well as spatial learning and memory. The pathways through which vestibular information modulate theta rhythm remain debatable. However, vestibular responses have been found in the pedunculopontine tegmental nucleus (PPTg) and activation of the vestibular system causes an increase in acetylcholine release into the hippocampus, probably from the medial septum. Therefore, a pathway from the vestibular nucleus complex and/or cerebellum to the PPTg, supramammillary nucleus, posterior hypothalamic nucleus, and septum to the hippocampus is likely. The modulation of theta by the vestibular system may have implications for vestibular effects on cognitive function and the contribution of vestibular impairment to the risk of dementia.
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Affiliation(s)
- Phillip Aitken
- Department of Pharmacology and Toxicology, School of Biomedical Sciences, and Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Yiwen Zheng
- Department of Pharmacology and Toxicology, School of Biomedical Sciences, and Brain Health Research Centre, University of Otago, Dunedin, New Zealand
- Brain Research New Zealand Centre of Research Excellence
- Eisdell Moore Centre for Hearing and Balance Research, University of Auckland, Auckland, New Zealand
| | - Paul F. Smith
- Department of Pharmacology and Toxicology, School of Biomedical Sciences, and Brain Health Research Centre, University of Otago, Dunedin, New Zealand
- Brain Research New Zealand Centre of Research Excellence
- Eisdell Moore Centre for Hearing and Balance Research, University of Auckland, Auckland, New Zealand
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28
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Is hippocampal neurogenesis modulated by the sensation of self-motion encoded by the vestibular system? Neurosci Biobehav Rev 2017; 83:489-495. [DOI: 10.1016/j.neubiorev.2017.09.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Revised: 09/10/2017] [Accepted: 09/10/2017] [Indexed: 01/26/2023]
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29
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Cronin T, Arshad Q, Seemungal BM. Vestibular Deficits in Neurodegenerative Disorders: Balance, Dizziness, and Spatial Disorientation. Front Neurol 2017; 8:538. [PMID: 29123498 PMCID: PMC5662638 DOI: 10.3389/fneur.2017.00538] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 09/26/2017] [Indexed: 12/13/2022] Open
Abstract
The vestibular system consists of the peripheral vestibular organs in the inner ear and the associated extensive central nervous system projections—from the cerebellum and brainstem to the thalamic relays to cortical projections. This system is important for spatial orientation and balance, both of critical ecological importance, particularly for successful navigation in our environment. Balance disorders and spatial disorientation are common presenting features of neurodegenerative diseases; however, little is known regarding central vestibular processing in these diseases. A ubiquitous aspect of central vestibular processing is its promiscuity given that vestibular signals are commonly found in combination with other sensory signals. This review discusses how impaired central processing of vestibular signals—typically in combination with other sensory and motor systems—may account for the impaired balance and spatial disorientation in common neurodegenerative conditions. Such an understanding may provide for new diagnostic tests, potentially useful in detecting early disease while a mechanistic understanding of imbalance and spatial disorientation in these patients may enable a vestibular-targeted therapy for such problems in neurodegenerative diseases. Studies with state of the art central vestibular testing are now much needed to tackle this important topic.
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Affiliation(s)
- Thomas Cronin
- Division of Brain Sciences, Department of Medicine, Charing Cross Hospital, London, United Kingdom
| | - Qadeer Arshad
- Division of Brain Sciences, Department of Medicine, Charing Cross Hospital, London, United Kingdom
| | - Barry M Seemungal
- Division of Brain Sciences, Department of Medicine, Charing Cross Hospital, London, United Kingdom
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30
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The vestibulocochlear bases for wartime posttraumatic stress disorder manifestations. Med Hypotheses 2017; 106:44-56. [DOI: 10.1016/j.mehy.2017.06.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 06/28/2017] [Indexed: 11/23/2022]
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31
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Zou D, Nishimaru H, Matsumoto J, Takamura Y, Ono T, Nishijo H. Experience-Related Changes in Place Cell Responses to New Sensory Configuration That Does Not Occur in the Natural Environment in the Rat Hippocampus. Front Pharmacol 2017; 8:581. [PMID: 28878682 PMCID: PMC5572398 DOI: 10.3389/fphar.2017.00581] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 08/11/2017] [Indexed: 12/02/2022] Open
Abstract
The hippocampal formation (HF) is implicated in a comparator that detects sensory conflict (mismatch) among convergent inputs. This suggests that new place cells encoding the new configuration with sensory mismatch develop after the HF learns to accept the new configuration as a match. To investigate this issue, HF CA1 place cell activity in rats was analyzed after the adaptation of the rats to the same sensory mismatch condition. The rats were placed on a treadmill on a stage that was translocated in a figure 8-shaped pathway. We recorded HF neuronal activities under three conditions; (1) an initial control session, in which both the stage and the treadmill moved forward, (2) a backward (mismatch) session, in which the stage was translocated backward while the rats locomoted forward on the treadmill, and (3) the second control session. Of the 161 HF neurons, 56 place-differential activities were recorded from the HF CA1 subfield. These place-differential activities were categorized into four types; forward-related, backward-related, both-translocation-related, and session-dependent. Forward-related activities showed predominant spatial firings in the forward sessions, while backward-related activities showed predominant spatial firings in the backward sessions. Both-translocation-related activities showed consistent spatial firings in both the forward and backward conditions. On the other hand, session-dependent activities showed different spatial firings across the sessions. Detailed analyses of the place fields indicated that mean place field sizes were larger in the forward-related, backward-related, and both-translocation-related activities than in the session-dependent activities. Furthermore, firing rate distributions in the place fields were negatively skewed and asymmetric, which is similar to place field changes that occur after repeated experience. These results demonstrate that the HF encodes a naturally impossible new configuration of sensory inputs after adaptation, suggesting that the HF is capable of updating its stored memory to accept a new configuration as a match by repeated experience.
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Affiliation(s)
- Dan Zou
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of ToyamaToyama, Japan.,Department of Pathophysiology, Shenyang Medical CollegeShenyang, China
| | - Hiroshi Nishimaru
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of ToyamaToyama, Japan
| | - Jumpei Matsumoto
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of ToyamaToyama, Japan
| | - Yusaku Takamura
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of ToyamaToyama, Japan
| | - Taketoshi Ono
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of ToyamaToyama, Japan
| | - Hisao Nishijo
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of ToyamaToyama, Japan
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Abstract
OBJECTIVE Recent studies suggest an association between vestibular and cognitive function. The goal of the study was to investigate whether vestibular function was impaired in individuals with mild cognitive impairment (MCI) and Alzheimer's disease (AD) compared with cognitively normal individuals. STUDY DESIGN Cross-sectional study. SETTING Outpatient memory clinic and longitudinal observational study unit. PATIENTS Older individuals ≥55 years with MCI or AD. Age, sex, and education-matched normal controls were drawn from the Baltimore Longitudinal Study of Aging (BLSA). INTERVENTION Saccular and utricular function was assessed with cervical and ocular vestibular-evoked myogenic potentials (c- and oVEMPs) respectively, and horizontal semicircular canal function was assessed with video head impulse testing. MAIN OUTCOME MEASURES Presence or absence of VEMP responses, VEMP amplitude, and vestibular ocular reflex (VOR) gain were measured. RESULTS Forty-seven individuals with cognitive impairment (MCI N = 15 and AD N = 32) underwent testing and were matched with 94 controls. In adjusted analyses, bilaterally absent cVEMPs were associated with an over three-fold odds of AD (OR 3.42, 95% CI 1.33-8.91, p = 0.011). One microvolt increases in both cVEMP and oVEMP amplitudes were associated with decreased odds of AD (OR 0.28, 95% CI 0.09-0.93, p = 0.038 and OR 0.92, 95% CI 0.85-0.99, p = 0.036, respectively). There was no significant difference in VOR gain between the groups. CONCLUSIONS These findings confirm and extend emerging evidence of an association between vestibular dysfunction and cognitive impairment. Further investigation is needed to determine the causal direction for the link between peripheral vestibular loss and cognitive impairment.
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Zheng Y, Gliddon CM, Aitken P, Stiles L, Machado ML, Philoxene B, Denise P, Smith PF, Besnard S. Effects of acute altered gravity during parabolic flight and/or vestibular loss on cell proliferation in the rat dentate gyrus. Neurosci Lett 2017. [DOI: 10.1016/j.neulet.2017.06.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Lee GW, Kim JH, Kim MS. Reduction of long-term potentiation at Schaffer collateral-CA1 synapses in the rat hippocampus at the acute stage of vestibular compensation. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2017; 21:423-428. [PMID: 28706456 PMCID: PMC5507781 DOI: 10.4196/kjpp.2017.21.4.423] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 05/06/2017] [Accepted: 06/12/2017] [Indexed: 11/15/2022]
Abstract
Vestibular compensation is a recovery process from vestibular symptoms over time after unilateral loss of peripheral vestibular end organs. The aim of the present study was to observe time-dependent changes in long-term potentiation (LTP) at Schaffer collateral-CA1 synapses in the CA1 area of the hippocampus during vestibular compensation. The input-output (I/O) relationships of fEPSP amplitudes and LTP induced by theta burst stimulation to Schaffer's collateral commissural fibers were evaluated from the CA1 area of hippocampal slices at 1 day, 1 week, and 1 month after unilateral labyrinthectomy (UL). The I/O relationships of fEPSPs in the CA1 area was significantly reduced within 1 week post-op and then showed a non-significant reduction at 1 month after UL. Compared with sham-operated animals, there was a significant reduction of LTP induction in the hippocampus at 1 day and 1 week after UL. However, LTP induction levels in the CA1 area of the hippocampus also returned to those of sham-operated animals 1 month following UL. These data suggest that unilateral injury of the peripheral vestibular end organs results in a transient deficit in synaptic plasticity in the CA1 hippocampal area at acute stages of vestibular compensation.
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Affiliation(s)
- Gyoung Wan Lee
- Department of Nursing, Wonkwang Health Science University, Iksan 54538, Korea
| | - Jae Hyo Kim
- Department of Meridian & Acupoint, College of Korean Medicine, Wonkwang University, Iksan 54538, Korea
| | - Min Sun Kim
- Department of Physiology, School of Medicine, Wonkwang University, Iksan 54538, Korea
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Butler WN, Smith KS, van der Meer MAA, Taube JS. The Head-Direction Signal Plays a Functional Role as a Neural Compass during Navigation. Curr Biol 2017; 27:1259-1267. [PMID: 28416119 DOI: 10.1016/j.cub.2017.03.033] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 02/24/2017] [Accepted: 03/15/2017] [Indexed: 10/19/2022]
Abstract
The rat limbic system contains head direction (HD) cells that fire according to heading in the horizontal plane, and these cells are thought to provide animals with an internal compass. Previous work has found that HD cell tuning correlates with behavior on navigational tasks, but a direct, causal link between HD cells and navigation has not been demonstrated. Here, we show that pathway-specific optogenetic inhibition of the nucleus prepositus caused HD cells to become directionally unstable under dark conditions without affecting the animals' locomotion. Then, using the same technique, we found that this decoupling of the HD signal in the absence of visual cues caused the animals to make directional homing errors and that the magnitude and direction of these errors were in a range that corresponded to the degree of instability observed in the HD signal. These results provide evidence that the HD signal plays a causal role as a neural compass in navigation.
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Affiliation(s)
- William N Butler
- Department of Psychological and Brain Sciences, Dartmouth College, 6207 Moore Hall, Hanover, NH 03755, USA
| | - Kyle S Smith
- Department of Psychological and Brain Sciences, Dartmouth College, 6207 Moore Hall, Hanover, NH 03755, USA
| | - Matthijs A A van der Meer
- Department of Psychological and Brain Sciences, Dartmouth College, 6207 Moore Hall, Hanover, NH 03755, USA
| | - Jeffrey S Taube
- Department of Psychological and Brain Sciences, Dartmouth College, 6207 Moore Hall, Hanover, NH 03755, USA.
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36
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Effects of bilateral vestibular deafferentation in rat on hippocampal theta response to somatosensory stimulation, acetylcholine release, and cholinergic neurons in the pedunculopontine tegmental nucleus. Brain Struct Funct 2017; 222:3319-3332. [PMID: 28349227 DOI: 10.1007/s00429-017-1407-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Accepted: 03/14/2017] [Indexed: 12/18/2022]
Abstract
Vestibular dysfunction has been shown to cause spatial memory impairment. Neurophysiological studies indicate that bilateral vestibular loss (BVL), in particular, is associated with an impairment of the response of hippocampal place cells and theta rhythm. However, the specific neural pathways through which vestibular information reaches the hippocampus are yet to be fully elucidated. The aim of the present study was to further investigate the hypothesised 'theta-generating pathway' from the brainstem vestibular nucleus to the hippocampus. BVL, and in some cases, unilateral vestibular loss (UVL), induced by intratympanic sodium arsanilate injections in rats, were used to investigate the effects of vestibular loss on somatosensory-induced type 2 theta rhythm, acetylcholine (ACh) release in the hippocampus, and the number of cholinergic neurons in the pedunculopontine tegmental nucleus (PPTg), an important part of the theta-generating pathway. Under urethane anaesthesia, BVL was found to cause a significant increase in the maximum power of the type 2 theta (3-6 Hz) frequency band compared to UVL and sham animals. Rats with BVL generally exhibited a lower basal level of ACh release than sham rats; however, this difference was not statistically significant. The PPTg of BVL rats exhibited significantly more choline-acetyltransferase (ChAT)-positive neurons than that of sham animals, as did the contralateral PPTg of UVL animals; however, the number of ChAT-positive neurons on the ipsilateral side of UVL animals was not significantly different from sham animals. The results of these studies indicate that parts of the theta-generating pathway undergo a significant reorganisation following vestibular loss, which suggests that this pathway is important for the interaction between the vestibular system and the hippocampus.
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Harvey RE, Thompson SM, Sanchez LM, Yoder RM, Clark BJ. Post-training Inactivation of the Anterior Thalamic Nuclei Impairs Spatial Performance on the Radial Arm Maze. Front Neurosci 2017; 11:94. [PMID: 28321178 PMCID: PMC5337504 DOI: 10.3389/fnins.2017.00094] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 02/13/2017] [Indexed: 12/15/2022] Open
Abstract
The limbic thalamus, specifically the anterior thalamic nuclei (ATN), contains brain signals including that of head direction cells, which fire as a function of an animal's directional orientation in an environment. Recent work has suggested that this directional orientation information stemming from the ATN contributes to the generation of hippocampal and parahippocampal spatial representations, and may contribute to the establishment of unique spatial representations in radially oriented tasks such as the radial arm maze. While previous studies have shown that ATN lesions can impair spatial working memory performance in the radial maze, little work has been done to investigate spatial reference memory in a discrimination task variant. Further, while previous studies have shown that ATN lesions can impair performance in the radial maze, these studies produced the ATN lesions prior to training. It is therefore unclear whether the ATN lesions disrupted acquisition or retention of radial maze performance. Here, we tested the role of ATN signaling in a previously learned spatial discrimination task on a radial arm maze. Rats were first trained to asymptotic levels in a task in which two maze arms were consistently baited across training. After 24 h, animals received muscimol inactivation of the ATN before a 4 trial probe test. We report impairments in post-inactivation trials, suggesting that signals from the ATN modulate the use of a previously acquired spatial discrimination in the radial-arm maze. The results are discussed in relation to the thalamo-cortical limbic circuits involved in spatial information processing, with an emphasis on the head direction signal.
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Affiliation(s)
- Ryan E Harvey
- Department of Psychology, University of New Mexico Albuquerque, NM, USA
| | | | | | - Ryan M Yoder
- Department of Psychology, Indiana-Purdue University Fort Wayne, IN, USA
| | - Benjamin J Clark
- Department of Psychology, University of New Mexico Albuquerque, NM, USA
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38
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Storage of passive motion pattern in hippocampal CA1 region depends on CaMKII/CREB signaling pathway in a motion sickness rodent model. Sci Rep 2017; 7:43385. [PMID: 28230177 PMCID: PMC5322525 DOI: 10.1038/srep43385] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 01/20/2017] [Indexed: 11/25/2022] Open
Abstract
Sensory mismatch between actual motion information and anticipated sensory patterns (internal model) is the etiology of motion sickness (MS). Some evidence supports that hippocampus might involve the neural storage of the “internal model”. This study established an “internal model” acquisition-retention behavioral model using a repeated habituation rotation training protocol. We tried to identify the hippocampal subregion involved in “internal model” retention using chemical lesion methods. Hippocampal kinases (CaMK, CaMKIV, CREB and ERK1/2) phosphorylation in the target subregion was assayed and the effects of kinase inhibitors (KN93 or U0126) on “internal model” retention were investigated. The activities of potential kinases (CaMKII and CREB) were also examined in otoliths deficit het/het mice. In habituated rats, CA1 lesion reproduced MS-related behavioral responses on “internal model” retention day. Habituation training increased CaMKII and CREB activity but had no effect on CaMKIV and ERK1/2 activity in the CA1, while inhibition of CaMKII but not ERK1/2 impaired “internal model” retention. In het/het mice, CaMKII and CREB were not activated in the CA1 on the retention day. These results suggested that CaMKII/CREB pathway might potentially contribute to the storage of the “internal model” in the hippocampal CA1 after motion sickness induced by vestibular stimulation.
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Aitken P, Benoit A, Zheng Y, Philoxene B, Le Gall A, Denise P, Besnard S, Smith PF. Hippocampal and striatal M1-muscarinic acetylcholine receptors are down-regulated following bilateral vestibular loss in rats. Hippocampus 2016; 26:1509-1514. [DOI: 10.1002/hipo.22651] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 08/17/2016] [Accepted: 08/25/2016] [Indexed: 12/21/2022]
Affiliation(s)
- Phillip Aitken
- Department of Pharmacology and Toxicology; Brain Health Research Centre University of Otago; Dunedin New Zealand
| | - Alice Benoit
- Normandie Univ, UNICAEN, INSERM, COMETE, CHU Caen; 14000 Caen France
| | - Yiwen Zheng
- Department of Pharmacology and Toxicology; Brain Health Research Centre University of Otago; Dunedin New Zealand
- Brain Research New Zealand Centre of Research Excellence; New Zealand
| | - Bruno Philoxene
- Normandie Univ, UNICAEN, INSERM, COMETE, CHU Caen; 14000 Caen France
| | - Anne Le Gall
- Normandie Univ, UNICAEN, INSERM, COMETE, CHU Caen; 14000 Caen France
| | - Pierre Denise
- Normandie Univ, UNICAEN, INSERM, COMETE, CHU Caen; 14000 Caen France
| | - Stephane Besnard
- Normandie Univ, UNICAEN, INSERM, COMETE, CHU Caen; 14000 Caen France
| | - Paul F. Smith
- Department of Pharmacology and Toxicology; Brain Health Research Centre University of Otago; Dunedin New Zealand
- Brain Research New Zealand Centre of Research Excellence; New Zealand
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40
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Basal dendritic length is reduced in the rat hippocampus following bilateral vestibular deafferentation. Neurobiol Learn Mem 2016; 131:56-60. [DOI: 10.1016/j.nlm.2016.03.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 03/02/2016] [Accepted: 03/02/2016] [Indexed: 12/18/2022]
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41
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Kremmyda O, Hüfner K, Flanagin VL, Hamilton DA, Linn J, Strupp M, Jahn K, Brandt T. Beyond Dizziness: Virtual Navigation, Spatial Anxiety and Hippocampal Volume in Bilateral Vestibulopathy. Front Hum Neurosci 2016; 10:139. [PMID: 27065838 PMCID: PMC4814552 DOI: 10.3389/fnhum.2016.00139] [Citation(s) in RCA: 113] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 03/15/2016] [Indexed: 12/30/2022] Open
Abstract
Bilateral vestibulopathy (BVP) is defined as the impairment or loss of function of either the labyrinths or the eighth nerves. Patients with total BVP due to bilateral vestibular nerve section exhibit difficulties in spatial memory and navigation and show a loss of hippocampal volume. In clinical practice, most patients do not have a complete loss of function but rather an asymmetrical residual functioning of the vestibular system. The purpose of the current study was to investigate navigational ability and hippocampal atrophy in BVP patients with residual vestibular function. Fifteen patients with BVP and a group of age- and gender- matched healthy controls were examined. Self-reported questionnaires on spatial anxiety and wayfinding were used to assess the applied strategy of wayfinding and quality of life. Spatial memory and navigation were tested directly using a virtual Morris Water Maze Task. The hippocampal volume of these two groups was evaluated by voxel-based morphometry. In the patients, the questionnaire showed a higher spatial anxiety and the Morris Water Maze Task a delayed spatial learning performance. MRI revealed a significant decrease in the gray matter mid-hippocampal volume (Left: p = 0.006, Z = 4.58, Right: p < 0.001, Z = 3.63) and posterior parahippocampal volume (Right: p = 0.005, Z = 4.65, Left: p < 0.001, Z = 3.87) compared to those of healthy controls. In addition, a decrease in hippocampal formation volume correlated with a more dominant route-finding strategy. Our current findings demonstrate that even partial bilateral vestibular loss leads to anatomical and functional changes in the hippocampal formation and objective and subjective behavioral deficits.
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Affiliation(s)
- Olympia Kremmyda
- German Center for Vertigo and Balance DisordersMunich, Germany; Department of Neurology, Ludwig-Maximilians UniversityMunich, Germany
| | - Katharina Hüfner
- Department of Psychiatry, Medical University Innsbruck Innsbruck, Austria
| | | | - Derek A Hamilton
- Department of Psychology, University of New Mexico Albuquerque, NM, USA
| | - Jennifer Linn
- Institute for Diagnostic and Interventional Neuroradiology, University Hospital Carl Gustav Carus Dresden, Germany
| | - Michael Strupp
- German Center for Vertigo and Balance DisordersMunich, Germany; Department of Neurology, Ludwig-Maximilians UniversityMunich, Germany
| | - Klaus Jahn
- German Center for Vertigo and Balance DisordersMunich, Germany; Department of Acute Neurology, Schön Klinik Bad AiblingBad Aibling, Germany
| | - Thomas Brandt
- German Center for Vertigo and Balance DisordersMunich, Germany; Institute for Clinical Neurosciences, Ludwig-Maximilians UniversityMunich, Germany
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42
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Göttlich M, Jandl NM, Sprenger A, Wojak JF, Münte TF, Krämer UM, Helmchen C. Hippocampal gray matter volume in bilateral vestibular failure. Hum Brain Mapp 2016; 37:1998-2006. [PMID: 26918638 DOI: 10.1002/hbm.23152] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 02/11/2016] [Indexed: 01/26/2023] Open
Abstract
Bilateral vestibular failure (BVF) is a severe chronic disorder of the labyrinth or the eighth cranial nerve characterized by unsteadiness of gait and disabling oscillopsia during head movements. According to animal data, vestibular input to the hippocampus is proposed to contribute to spatial memory and spatial navigation. Except for one seminal study showing the association of impaired spatial navigation and hippocampal atrophy, patient data in BVF are lacking. Therefore, we performed a voxel-wise comparison of the hippocampal gray matter volume (GMV) in a clinically representative sample of 27 patients with incomplete BVF and 29 age- and gender-matched healthy controls to test the hypothesis of hippocampal atrophy in BVF. Although the two groups did not generally differ in their hippocampal GMV, a reduction of GMV in the bilateral hippocampal CA3 region was significantly correlated with increased vestibulopathy-related clinical impairment. We propose that GMV reduction in the hippocampus of BVF patients is related to the severity of vestibular-induced disability which is in line with combined hippocampal atrophy and disorders of spatial navigation in complete vestibular deafferentation due to bilateral nerve section. Clinically, however, the most frequent etiologies of BVF cause incomplete lesions. Accordingly, hippocampus atrophy and deficits in spatial navigation occur possibly less frequently than previously suspected. Hum Brain Mapp 37:1998-2006, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Martin Göttlich
- Department of Neurology, University of Lübeck and University Hospital Schleswig-Holstein, Lübeck, Germany
| | - Nico M Jandl
- Department of Neurology, University of Lübeck and University Hospital Schleswig-Holstein, Lübeck, Germany
| | - Andreas Sprenger
- Department of Neurology, University of Lübeck and University Hospital Schleswig-Holstein, Lübeck, Germany.,Institute of Psychology II, University of Lübeck, Lübeck, Germany
| | - Jann F Wojak
- Department of Neurology, University of Lübeck and University Hospital Schleswig-Holstein, Lübeck, Germany
| | - Thomas F Münte
- Department of Neurology, University of Lübeck and University Hospital Schleswig-Holstein, Lübeck, Germany.,Institute of Psychology II, University of Lübeck, Lübeck, Germany
| | - Ulrike M Krämer
- Department of Neurology, University of Lübeck and University Hospital Schleswig-Holstein, Lübeck, Germany.,Institute of Psychology II, University of Lübeck, Lübeck, Germany
| | - Christoph Helmchen
- Department of Neurology, University of Lübeck and University Hospital Schleswig-Holstein, Lübeck, Germany
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43
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Gale S, Prsa M, Schurger A, Gay A, Paillard A, Herbelin B, Guyot JP, Lopez C, Blanke O. Oscillatory neural responses evoked by natural vestibular stimuli in humans. J Neurophysiol 2015; 115:1228-42. [PMID: 26683063 DOI: 10.1152/jn.00153.2015] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 12/12/2015] [Indexed: 11/22/2022] Open
Abstract
While there have been numerous studies of the vestibular system in mammals, less is known about the brain mechanisms of vestibular processing in humans. In particular, of the studies that have been carried out in humans over the last 30 years, none has investigated how vestibular stimulation (VS) affects cortical oscillations. Here we recorded high-density electroencephalography (EEG) in healthy human subjects and a group of bilateral vestibular loss patients (BVPs) undergoing transient and constant-velocity passive whole body yaw rotations, focusing our analyses on the modulation of cortical oscillations in response to natural VS. The present approach overcame significant technical challenges associated with combining natural VS with human electrophysiology and reveals that both transient and constant-velocity VS are associated with a prominent suppression of alpha power (8-13 Hz). Alpha band suppression was localized over bilateral temporo-parietal scalp regions, and these alpha modulations were significantly smaller in BVPs. We propose that suppression of oscillations in the alpha band over temporo-parietal scalp regions reflects cortical vestibular processing, potentially comparable with alpha and mu oscillations in the visual and sensorimotor systems, respectively, opening the door to the investigation of human cortical processing under various experimental conditions during natural VS.
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Affiliation(s)
- Steven Gale
- Center for Neuroprosthetics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; Laboratory of Cognitive Neuroscience, Brain-Mind Institute, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Mario Prsa
- Center for Neuroprosthetics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; Laboratory of Cognitive Neuroscience, Brain-Mind Institute, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Aaron Schurger
- Center for Neuroprosthetics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; Laboratory of Cognitive Neuroscience, Brain-Mind Institute, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Annietta Gay
- Department of Otorhinolaryngology, University Hospital Geneva, Geneva, Switzerland
| | - Aurore Paillard
- Laboratory of Cognitive Neuroscience, Brain-Mind Institute, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Bruno Herbelin
- Center for Neuroprosthetics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; Laboratory of Cognitive Neuroscience, Brain-Mind Institute, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Jean-Philippe Guyot
- Department of Otorhinolaryngology, University Hospital Geneva, Geneva, Switzerland
| | - Christophe Lopez
- Aix Marseille Université, CNRS, NIA UMR 7260, Marseille, France; and
| | - Olaf Blanke
- Center for Neuroprosthetics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; Laboratory of Cognitive Neuroscience, Brain-Mind Institute, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; Department of Neurology, University Hospital Geneva, Geneva, Switzerland
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44
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Wolff AR, Bilkey DK. Prenatal immune activation alters hippocampal place cell firing characteristics in adult animals. Brain Behav Immun 2015; 48:232-43. [PMID: 25843370 DOI: 10.1016/j.bbi.2015.03.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 03/12/2015] [Accepted: 03/24/2015] [Indexed: 12/27/2022] Open
Abstract
Prenatal maternal immune activation (MIA) is a risk factor for several developmental neuropsychiatric disorders, including autism, bipolar disorder and schizophrenia. Adults with these disorders display alterations in memory function that may result from changes in the structure and function of the hippocampus. In the present study we use an animal model to investigate the effect that a transient prenatal maternal immune activation episode has on the spatially-modulated firing activity of hippocampal neurons in adult animals. MIA was induced in pregnant rat dams with a single injection of the synthetic cytokine inducer polyinosinic:polycytidylic acid (poly I:C) on gestational day 15. Control dams were given a saline equivalent. Firing activity and local field potentials (LFPs) were recorded from the CA1 region of the adult male offspring of these dams as they moved freely in an open arena. Most neurons displayed characteristic spatially-modulated 'place cell' firing activity and while there was no between-group difference in mean firing rate between groups, place cells had smaller place fields in MIA-exposed animals when compared to control-group cells. Cells recorded in MIA-group animals also displayed an altered firing-phase synchrony relationship to simultaneously recorded LFPs. When the floor of the arena was rotated, the place fields of MIA-group cells were more likely to shift in the same direction as the floor rotation, suggesting that local cues may have been more salient for these animals. In contrast, place fields in control group cells were more likely to shift firing position to novel spatial locations suggesting an altered response to contextual cues. These findings show that a single MIA intervention is sufficient to change several important characteristics of hippocampal place cell activity in adult offspring. These changes could contribute to the memory dysfunction that is associated with MIA, by altering the encoding of spatial context and by disrupting plasticity mechanisms that are dependent on spike timing synchrony.
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Affiliation(s)
- Amy R Wolff
- Department of Psychology, Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - David K Bilkey
- Department of Psychology, Brain Health Research Centre, University of Otago, Dunedin, New Zealand.
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45
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Abstract
Much of our understanding of the neuronal mechanisms of spatial navigation is derived from chronic recordings in rodents in which head-direction, place, and grid cells have all been described. However, despite the proposed importance of self-reference information to these internal representations of space, their congruence with vestibular signaling remains unclear. Here we have undertaken brain-wide functional mapping using both fMRI and electrophysiological methods to directly determine the spatial extent, strength, and time course of vestibular signaling across the rat forebrain. We find distributed activity throughout thalamic, limbic, and particularly primary sensory cortical areas in addition to known head-direction pathways. We also observe activation of frontal regions, including infralimbic and cingulate cortices, indicating integration of vestibular information throughout functionally diverse cortical regions. These whole-brain activity maps therefore suggest a widespread contribution of vestibular signaling to a self-centered framework for multimodal sensorimotor integration in support of movement planning, execution, spatial navigation, and autonomic responses to gravito-inertial changes.
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46
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Stiles L, Smith PF. The vestibular–basal ganglia connection: Balancing motor control. Brain Res 2015; 1597:180-8. [PMID: 25498858 DOI: 10.1016/j.brainres.2014.11.063] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 11/27/2014] [Accepted: 11/29/2014] [Indexed: 12/31/2022]
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47
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Yoder RM, Goebel EA, Köppen JR, Blankenship PA, Blackwell AA, Wallace DG. Otolithic information is required for homing in the mouse. Hippocampus 2015; 25:890-9. [PMID: 25565056 DOI: 10.1002/hipo.22410] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/30/2014] [Indexed: 11/11/2022]
Abstract
Navigation and the underlying brain signals are influenced by various allothetic and idiothetic cues, depending on environmental conditions and task demands. Visual landmarks typically control navigation in familiar environments but, in the absence of landmarks, self-movement cues are able to guide navigation relatively accurately. These self-movement cues include signals from the vestibular system, and may originate in the semicircular canals or otolith organs. Here, we tested the otolithic contribution to navigation on a food-hoarding task in darkness and in light. The dark test prevented the use of visual cues and thus favored the use of self-movement information, whereas the light test allowed the use of both visual and non-visual cues. In darkness, tilted mice made shorter-duration stops during the outward journey, and made more circuitous homeward journeys than control mice; heading error, trip duration, and peak error were greater for tilted mice than for controls. In light, tilted mice also showed more circuitous homeward trips, but appeared to correct for errors during the journey; heading error, trip duration, and peak error were similar between groups. These results suggest that signals from the otolith organs are necessary for accurate homing performance in mice, with the greatest contribution in non-visual environments.
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Affiliation(s)
- Ryan M Yoder
- Department of Psychology, Indiana University-Purdue University Fort Wayne, Fort Wayne, Indiana
| | - Elizabeth A Goebel
- Department of Psychology, Indiana University-Purdue University Fort Wayne, Fort Wayne, Indiana
| | - Jenny R Köppen
- Department of Psychology, Northern Illinois University, DeKalb, Illinois
| | | | - Ashley A Blackwell
- Department of Psychology, Northern Illinois University, DeKalb, Illinois
| | - Douglas G Wallace
- Department of Psychology, Northern Illinois University, DeKalb, Illinois
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Smith P, Darlington C, Zheng Y. The Effects of Complete Vestibular Deafferentation on Spatial Memory and the Hippocampus in the Rat: The Dunedin Experience. Multisens Res 2015; 28:461-85. [DOI: 10.1163/22134808-00002469] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Our studies conducted over the last 14 years have demonstrated that a complete bilateral vestibular deafferentation (BVD) in rats results in spatial memory deficits in a variety of behavioural tasks, such as the radial arm maze, the foraging task and the spatial T maze, as well as deficits in other tasks such as the five-choice serial reaction time task (5-CSRT task) and object recognition memory task. These deficits persist long after the BVD, and are not simply attributable to ataxia, anxiety, hearing loss or hyperactivity. In tasks such as the foraging task, the spatial memory deficits are evident in darkness when vision is not required to perform the task. The deficits in the radial arm maze, the foraging task and the spatial T maze, in particular, suggest hippocampal dysfunction following BVD, and this is supported by the finding that both hippocampal place cells and theta rhythm are dysfunctional in BVD rats. Now that it is clear that the hippocampus is adversely affected by BVD, the next challenge is to determine what vestibular information is transmitted to it and how that information is used by the hippocampus and the other brain structures with which it interacts.
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Affiliation(s)
- Paul F. Smith
- Dept. Pharmacology and Toxicology, School of Medical Sciences, and the Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Cynthia L. Darlington
- Dept. Pharmacology and Toxicology, School of Medical Sciences, and the Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Yiwen Zheng
- Dept. Pharmacology and Toxicology, School of Medical Sciences, and the Brain Health Research Centre, University of Otago, Dunedin, New Zealand
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Aghajan ZM, Acharya L, Moore JJ, Cushman JD, Vuong C, Mehta MR. Impaired spatial selectivity and intact phase precession in two-dimensional virtual reality. Nat Neurosci 2014; 18:121-8. [DOI: 10.1038/nn.3884] [Citation(s) in RCA: 169] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 10/29/2014] [Indexed: 02/07/2023]
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Plank M, Snider J, Kaestner E, Halgren E, Poizner H. Neurocognitive stages of spatial cognitive mapping measured during free exploration of a large-scale virtual environment. J Neurophysiol 2014; 113:740-53. [PMID: 25376779 DOI: 10.1152/jn.00114.2014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Using a novel, fully mobile virtual reality paradigm, we investigated the EEG correlates of spatial representations formed during unsupervised exploration. On day 1, subjects implicitly learned the location of 39 objects by exploring a room and popping bubbles that hid the objects. On day 2, they again popped bubbles in the same environment. In most cases, the objects hidden underneath the bubbles were in the same place as on day 1. However, a varying third of them were misplaced in each block. Subjects indicated their certainty that the object was in the same location as the day before. Compared with bubble pops revealing correctly placed objects, bubble pops revealing misplaced objects evoked a decreased negativity starting at 145 ms, with scalp topography consistent with generation in medial parietal cortex. There was also an increased negativity starting at 515 ms to misplaced objects, with scalp topography consistent with generation in inferior temporal cortex. Additionally, misplaced objects elicited an increase in frontal midline theta power. These findings suggest that the successive neurocognitive stages of processing allocentric space may include an initial template matching, integration of the object within its spatial cognitive map, and memory recall, analogous to the processing negativity N400 and theta that support verbal cognitive maps in humans.
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Affiliation(s)
- Markus Plank
- Institute for Neural Computation, University of California, San Diego, La Jolla, California
| | - Joseph Snider
- Institute for Neural Computation, University of California, San Diego, La Jolla, California
| | - Erik Kaestner
- Interdepartmental Neuroscience Program, University of California, San Diego, La Jolla, California; and
| | - Eric Halgren
- Interdepartmental Neuroscience Program, University of California, San Diego, La Jolla, California; and Departments of Radiology, Neurosciences, and Psychiatry, University of California, San Diego, La Jolla, California
| | - Howard Poizner
- Institute for Neural Computation, University of California, San Diego, La Jolla, California; Interdepartmental Neuroscience Program, University of California, San Diego, La Jolla, California; and
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