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Impaired spatial coding of the hippocampus in a dentate gyrus hypoplasia mouse model

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2025年第5期122卷 e2416214122页

作者： Chen, Xiaojing Cheng, Ning Wang, Cheng Knierim, James J. Southern Univ Sci & Technol Brain Res Ctr Sch Life Sci Dept Neurosci Shenzhen 518055 Peoples R China Johns Hopkins Univ Zanvyl Krieger Mind Brain Inst Baltimore MD 21218 USA Chinese Acad Sci Shenzhen Inst Adv Technol Brain Cognit & Brain Dis Inst Shenzhen 518055 Peoples R China Johns Hopkins Univ Solomon H Snyder Dept Neurosci Baltimore MD 21218 USA Johns Hopkins Univ Dept Psychol & Brain Sci Baltimore MD 21218 USA Johns Hopkins Univ Kavli Neurosci Discovery Inst Baltimore MD 21218 USA

The hippocampal dentate gyrus (DG) is thought to orthogonalize inputs from the entorhinal cortex (pattern separation) and relay this information to the CA3 region. In turn, attractor dynamics in CA3 perform a pattern completion or error correction operation before sending its output to CA1. In a mouse model of congenital hypo-plasia of the DG, a deficiency in the Wntless (Wls) gene, specifically in cells expressing Gfap- Cre, which targets neuronal progenitors, led to an almost total absence of dentate granule cells and modestly impaired performance in spatial tasks. Here, we investigated the physiological consequences of granule cell loss in these mice by conducting in vivo calcium imaging from CA1 principal cells during behavior. The spatial selectivity of these cells was preserved without the DG. On a linear track, place fields in mutant mice were more likely to be near track terminals and to encode the distance from the start point in each running direction. In an open box, CA1 cells in mutant mice exhibited reductions in the percentage of place cells, in spatial information, and in place field stability. The reduction in place field stability across repeated exposures to the same environment resulted in a reduction in the differential representations of two different contexts in mutant mice compared to wild- type mice. These results suggest that DG helps to stabilize CA1 spatial representations, especially in 2- D environments, and that the lack of stability across similar environments may play a key role in the deficits of animals with DG dysfunction in discriminating different environments.

关键词： dentate gyrus place cell spatial coding Wnt calcium imaging

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spatial coding metastructure for single-sensor impact region recognition

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SMART MATERIALS AND STRUCTURES 2024年第10期33卷 105041-105041页

作者： Jiang, Tianxi Zhou, Tianyue Wang, Xihao Li, Tianqi Jin, Hu Zhang, Shiwu Peng, Zhi-Ke He, Qingbo Univ Sci & Technol China Inst Humanoid Robots Dept Precis Machinery & Precis Instrumentat Hefei 230026 Peoples R China Shanghai Jiao Tong Univ State Key Lab Mech Syst & Vibrat Shanghai 200240 Peoples R China Ningxia Univ Sch Mech Engn Yinchuan 750021 Peoples R China

The rapid development of aircraft has created a strong demand for structural health monitoring, but current methods that rely on multiple sensor fusion suffer from complex hardware systems. Computational sensing with metastructures provides a promising approach to reduce sensing cost, but the lack of calibrated information makes it challenging to identify impact regions. In this study, we propose a concept of spatial coding metastructure for impact region recognition with a single sensor. Owing to the multi-order local resonance effect, the metastructures are capable of producing multiple vibration modulations over a wide frequency band. We demonstrate that the frequency-dependent vibration modulation effects of the metastructures on different test regions are distinguishable, a characteristic referred to as spatial coding. This characteristic enables impact regions to be accurately recognized with only a single sensor by using machine learning methods. Our work not only presents promising application prospects for condition monitoring of aircraft and other mechanical systems, but also inspires the development of safer and more efficient systems in various industries.

关键词： spatial coding metastructure impact region recognition single sensor

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spatial coding in sonar imaging

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ELECTRONICS LETTERS 2017年第17期53卷 1222-1224页

作者： Wang, Jingxi Guo, Xin Ge, Feng-Xiang Arce, Gonzalo R. Beijing Normal Univ Beijing Peoples R China Huawei Technol Co Ltd Beijing Peoples R China Univ Delaware Newark DE 19716 USA

A practical deployment is presented for sonar imaging with fewer transmitters and receivers. spatial coding via transmit beamforming is used for target detection and localisation. Transmit beamforming reduces the ambiguity in a model and improves imaging performance. To reconstruct the resultant underdetermined system of equations, a sparse signal reconstruction framework is used, and the inverse problem is solved by using an iterative optimisation algorithm. Deployment is optimised for better target detection and localisation performance. Successful sonar imaging reconstruction is guaranteed by the restricted isometry property with high probability. A numerical simulation shows that the proposed method can detect and localise targets efficiently, with better imaging results than those attained by conventional methods or the compressive sensing method without spatial coding.

关键词： sonar imaging image coding sonar detection object detection transmitters receivers array signal processing inverse problems iterative methods optimisation image reconstruction probability spatial coding transmitter receiver beamforming target detection target localisation sparse signal reconstruction framework inverse problem iterative optimisation algorithm sonar imaging reconstruction restricted isometry property probability numerical simulation compressive sensing method

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spatial coding of eye movements relative to perceived earth and head orientations during static roll tilt

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EXPERIMENTAL BRAIN RESEARCH 1998年第1期121卷 51-58页

作者： Wood, SJ Paloski, WH Reschke, MF KRUG Life Sci Neurosci Lab Houston TX USA

This purpose of this study was to examine the spatial coding of eye movements during static roll tilt (up to +/-45 degrees) relative to perceived earth and head orientations. Binocular videographic recordings obtained in darkness from eight subjects allowed us to quantify the mean deviations in gaze trajectories along both horizontal and vertical coordinates relative to the true earth and head orientations. We found that both variability and curvature of gaze trajectories increased with roll tilt. The trajectories of eye movements made along the perceived earth-horizontal (PEH) were more accurate than movements along the perceived head-horizontal (PHH). The trajectories of both PEH and PHH saccades tended to deviate in the same direction as the head tilt. The deviations in gaze trajectories along the perceived earth-vertical (PEV) and perceived head-vertical (PHV) were both similar to the PHH orientation, except that saccades along the PEV deviated in the opposite direction relative to the head tilt. The magnitude of deviations along the PEV, PHH, and Pi-IV corresponded to perceptual overestimations of roll tilt obtained from verbal reports. Both PEV gaze trajectories and perceptual estimates of tilt orientation were different following clockwise rather than counterclockwise tilt rotation;however, the PEH gaze trajectories were less affected by the direction of tilt rotation. Our results suggest that errors in gaze trajectories along PEV and perceived head orientations increase during roll tilt in a similar way to perceptual errors of tilt orientation. Although PEH and PEV gaze trajectories became nonorthogonal during roll tilt, we conclude that the spatial coding of eye movements during roll tilt is overall more accurate for the perceived earth reference frame than for the perceived head reference frame.

关键词： spatial coding saccades tilt perception adaption human

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spatial coding and invariance in object-selective cortex

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CORTEX 2011年第1期47卷 14-22页

作者： Carlson, Thomas Hogendoorn, Hinze Fonteijn, Hubert Verstraten, Frans A. J. Univ Maryland Dept Psychol College Pk MD 20740 USA Harvard Univ Dept Psychol Vis Sci Lab Cambridge MA 02138 USA Univ Utrecht Helmholtz Inst NL-3508 TC Utrecht Netherlands Radboud Univ Nijmegen FC Donders Ctr Cognit Neuroimaging Nijmegen Netherlands

The present study examined the coding of spatial position in object selective cortex. Using functional magnetic resonance imaging (fMRI) and pattern classification analysis, we find that three areas in object selective cortex, the lateral occipital cortex area (LO), the fusiform face area (FFA), and the parahippocampal place area (PPA), robustly code the spatial position of objects. The analysis further revealed several anisotropies (e.g., horizontal/vertical asymmetry) in the representation of visual space in these areas. Finally, we show that the representation of information in these areas permits object category information to be extracted across varying locations in the visual field;a finding that suggests a potential neural solution to accomplishing translation invariance. (C) 2009 Elsevier Srl. All rights reserved.

关键词： Object recognition fMRI spatial coding Object invariance

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spatial coding OF OLFACTORY INFORMATION IN THE ANTENNAL LOBE OF DROSOPHILA-MELANOGASTER

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BRAIN RESEARCH 1988年第1-2期453卷 299-307页

作者： RODRIGUES, V MAX PLANCK INST BIOL CYBERNET D-7400 TUBINGEN FED REP GER

[3H]2-deoxyglucose autoradiography has revealed foci in the antennal lobe of Drosophila melanogaster that are active during olfactory stimulation. Labeling in the receptor axons and the lobe interneurons can be observed. Each class of odors stimulates activity in a specific subset of antennal glomeruli. This defines the activity domain, which is recognizably distinct, although overlapping, for different classes of volatile chemicals. Unilateral stimulation with attractants predominantly results in excitation of the ipsilateral glomeruli. Collaterals of the receptor neurons to the contralateral lobe stimulate no visible postsynaptic activity. On the other hand, unilateral stimulation with repellent odors, such as benzaldehyde, results in an equally strong activity in both antennal lobes.

关键词： spatial coding Olfaction Antennal lobe Olfactory stimulation Deoxyglucose Autoradiography

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Entity-oriented spatial coding scheme and its application for spatial topology

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地球空间信息科学学报（英文版） 2024年第1期27卷 183-201页

作者： Weining Zhu Department of Marine Informatics Ocean CollegeZhejiang UniversityHangzhouChina

Based on a newly proposed spatial data model spatial Chromatic Model(SCM),we developed a spatial coding scheme,called the full-coded Ordinary Arranged Chromatic Diagram(full-OACD).As a type of spatial tessellation,full-OACD partitions a geographic space into a number of subspaces,such as cells,edges,and *** subspaces are called spatial particles and are assigned with unique codes chromatic *** generation,structure,computation,and properties of full-OACD are *** between particulate chromatic codes and spatial topology are ***-OACD is a kind of new discrete spatial coordinate system where the information of real-world entities is ***-OACD provides an informative and meaningful spatial coding framework for spatial topological analysis and many other potential applications in geospatial information science.

关键词： spatial data model spatial coding spatial tessellation spatial topology

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spatial coding of Individuals With Visual Impairments

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JOURNAL OF SPECIAL EDUCATION 2012年第3期46卷 180-190页

作者： Papadopoulos, Konstantinos Koustriava, Eleni Kartasidou, Lefkothea Univ Macedonia PC Thessaloniki 54006 Greece

The aim of this study is to examine the ability of children and adolescents with visual impairments to code and represent near space. Moreover, it examines the impact of the strategies they use and individual differences in their performance. A total of 30 individuals with visual impairments up to the age of 18 were given eight different object patterns in different arrays and were asked to code and represent each of them. The results revealed better performances by those who use an allocentric approach during spatial coding and those with residual vision. In fact, allocentric strategies were more prevalent in coding near space than egocentric ones. Moreover, the ability of participants to move independently was positively correlated with their ability to use the most effective haptic strategies. These findings suggest that children and adolescents with visual impairments are capable of using allocentric reference and providing a different perspective to the currently dominant one.

关键词： visual impairments spatial representation spatial coding near space

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Sharing spatial information in a virtual environment: How do visual cues and configuration influence spatial coding and mental workload?

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VIRTUAL REALITY 2020年第4期24卷 695-712页

作者： Milleville-Pennel, Isabelle Mars, Franck Pouliquen-Lardy, Lauriane Univ Nantes LS2N Cent Nantes CNRS BP 92101 F-44321 Nantes 03 France

When sharing virtual collaborative environments, operators exchange spatial statements that refer to the objects' positions in the virtual space. If operators are to understand each other, they need to develop a common spatial frame of reference and then choose a space coding to describe the objects' positions. In this paper, we consider how the content of a virtual environment can influence communication between users. We designed two studies in which one participant (the speaker) had to indicate the position of one object to another participant (the addressee). The virtual environment was sometimes enriched by additional (proximal and distal) visual cues. In study 1, we considered statements production. We observed that the speakers most often used the avatar of their partner as a spatial reference to indicate a localization in the virtual space (i.e., Addressee-Centered coding) despite it increases their mental workload. Nevertheless, in complex situations, they also used distal cues to speak to the addressees (i.e., Exocentric coding of the space). In study 2, we considered statements comprehension. Addressee-Centered coding and Exocentric coding were used by the speakers in various spatial configurations to indicate the object position. We observed that Exocentric coding is the most difficult to manage for the addressee. These results indicate that speakers implemented the principle of less collaborative effort by adopting a way of exchanging information based on an asymmetrical cognitive cost, taking into consideration each other's difficulties. This allows a balanced mental workload to be maintained between the two operators throughout the task.

关键词： Common spatial frame of reference spatial coding Mental workload Least collaborative effort Virtual environments

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Non-quantum implementation of quantum computation algorithm using a spatial coding technique

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OPTICS COMMUNICATIONS 2005年第1-3期251卷 124-131页

作者： Tate, N Ogura, Y Tanida, J Osaka Univ Grad Sch Informat Sci & Technol Suita Osaka 5650871 Japan

Non-quantum implementation of quantum information processing is studied. A spatial coding technique, which is one effective digital optical computing technique, is utilized to implement quantum teleportation efficiently. In the coding, quantum information is represented by the intensity and the phase of elemental cells. Correct operation is confirmed within the proposed scheme, which indicates the effectiveness of the proposed approach and a motive for further investigation. (c) 2005 Elsevier B.V. All rights reserved.

关键词： optical computing spatial coding quantum teleportation

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