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Physiological constraints of visual pathway lead to more efficient coding of information in retina

JOURNAL OF THEORETICAL BIOLOGY 2020年 506卷 110418-110418页

作者： Farzanfar, Arezoo Shayegh, Farzaneh Nazari, Behzad Sadri, Saeid Isfahan Univ Technol Dept Elect & Comp Engn Esfahan *** Iran

Nowadays, numerous studies have investigated the modeling of efficient neural encoding processes in the retina of the eye to encode the sensory data. Retina, as the innermost coat of the eye, is the first and the most important area of the visual neural system of mammalians, which is responsible for neural processes. Retina encodes the information of light intensity into a sequence of spikes, and sends them to retinal ganglion cells (RGCs) for further processing. An appropriate retinal encoding model should be adapted to the real retina as much as possible by considering the physiological constraints of the visual pathway to transfer most of the information of the input signal to the brain without too much redundancy of the channel. In this paper, inspired from the existing linear models of retinal encoding process, which have employed input noise and the spatial locality of the RGCs receptive fields (RFs) in the calculation of the encoding matrix, two extra physiological constraints, adapted from the real retina are taken into account so as to achieve a more realistic model for the mammalian retina. These new constraints that are the correlation between RGCs and the spatial locality of the photoreceptors' projective fields (PFs), are modeled in a mathematical form and analyzed in detail. To quantify fidelity of the proposed encoding matrix and prove its superiority over existing models, various parameters of the models are calculated and presented in this paper: mean square error between the original and reconstructed image (MSE), the redundancy of the channel, the amount of information transferred through the channel, and the amount of wasted capacity for carrying input noise, to name a few. The results of these calculations show that the proposed model transfers input information with less redundancy of the channel. In other words, it reduces a portion of channel capacity which is wasted for carrying the input noise in comparison to the existing models. Also, due

关键词： Retina efficient coding Physiological constraints Receptive field Center-surround

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efficient coding of spectrotemporal binaural sounds leads to emergence of the auditory space representation

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FRONTIERS IN COMPUTATIONAL NEUROSCIENCE 2014年第MAR期8卷 26页

作者： Mlynarski, Wiktor Max Planck Inst Math Sci D-04123 Leipzig Germany

To date a number of studies have shown that receptive field shapes of early sensory neurons can be reproduced by optimizing coding efficiency of natural stimulus ensembles. A still unresolved question is whether the efficient coding hypothesis explains formation of neurons which explicitly represent environmental features of different functional importance. This paper proposes that the spatial selectivity of higher auditory neurons emerges as a direct consequence of learning efficient codes for natural binaural sounds. Firstly, it is demonstrated that a linear efficient coding transform Independent Component Analysis (ICA) trained on spectrograms of naturalistic simulated binaural sounds extracts spatial information present in the signal. A simple hierarchical ICA extension allowing for decoding of sound position is proposed. Furthermore, it is shown that units revealing spatial selectivity can be learned from a binaural recording of a natural auditory scene. In both cases a relatively small subpopulation of learned spectrogram features suffices to perform accurate sound localization. Representation of the auditory space is therefore learned in a purely unsupervised way by maximizing the coding efficiency and without any task-specific constraints. This results imply that efficient coding is a useful strategy for learning structures which allow for making behaviorally vital inferences about the environment.

关键词： efficient coding natural sound statistics binaural hearing spectrotemporal receptive fields auditory scene analysis

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ECG compression by efficient coding

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7th International Conference on Independent Component Analysis and Signal Separation

作者： Guilhon, Denner Barros, Allan K. Comani, Silvia Fed Univ Maranhao UFMA Sao Luis MA Brazil Univ G dAnnunzio Dept Clin sci & Bioimaging Chieti Italy Univ G dAnnunzio Univ Fdn GD Annunizo ITAB Chieti Italy

ISBN: (纸本)9783540744931

The continuous demand for high performance and low cost electrocardiogram (ECG) processing systems have required the elaboration of more and more efficient and reliable ECG compression techniques. Such techniques face a tradeoff between compression ratio and retrieved quality, where the decrease of the last can compromise the subsequent use of the signal for clinical purposes. The objective of this work is to evaluate the validity and performance of an independent component analysis (ICA) based scheme used to efficiently compress ECC signals while introducing tests for a different type of record of the electrical activity of the heart, such as fetal magnetocardiogram (fMCG). As a result, the reconstructed signals underwent negligible visual deterioration, while achieving promising compression ratios.

关键词： independent component analysis efficient coding electrocardiogram fetal magnetocardiogram

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From efficient coding to Information Gain: Information-Theoretic Principles in Models of Human Decision Making 42

From Efficient Coding to Information Gain: Information-Theor...

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42nd Annual Meeting of the Cognitive Science Society: Developing a Mind: Learning in Humans, Animals, and Machines, CogSci 2020

作者： Akrenius, Mikaela Maloney, Laurence T. Nelson, Jonathan D. Cognitive Science Program Indiana University Bloomington United States Department of Psychology Center for Neural Science New York University United States School of Psychology University of Surrey Max Planck Institute for Human Development Berlin Germany

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efficient coding by Midget and Parasol Ganglion Cells in the Human Retina

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NEURON 2020年第4期107卷 656-+页

作者： Soto, Florentina Hsiang, Jen-Chun Rajagopal, Rithwick Piggott, Kisha Harocopos, George J. Couch, Steven M. Custer, Philip Morgan, Josh L. Kerschensteiner, Daniel Washington Univ Dept Ophthalmol & Visual Sci Sch Med St Louis St Louis MO 63110 USA Washington Univ Grad Program Neurosci Sch Med St Louis MO 63110 USA Washington Univ Dept Neurosci Sch Med St Louis MO 63110 USA Washington Univ Dept Biomed Engn Sch Med St Louis MO 63110 USA Washington Univ Hope Ctr Neurol Disorders Sch Med St Louis MO 63110 USA

In humans, midget and parasol ganglion cells account for most of the input from the eyes to the brain. Yet, how they encode visual information is unknown. Here, we perform large-scale multi-electrode array recordings from retinas of treatment-naive patients who underwent enucleation surgery for choroidal malignant melanomas. We identify robust differences in the function of midget and parasol ganglion cells, consistent asymmetries between their ON and OFF types (that signal light increments and decrements, respectively) and divergence in the function of human versus non-human primate retinas. Our computational analyses reveal that the receptive fields of human midget and parasol ganglion cells divide naturalistic movies into adjacent spatiotemporal frequency domains with equal stimulus power, while the asymmetric response functions of their ON and OFF types simultaneously maximize stimulus coverage and information transmission and minimize metabolic cost. Thus, midget and parasol ganglion cells in the human retina efficiently encode our visual environment.

关键词： mutual information white noise parallel processing redundancy LN model naturalistic movies metabolic cost efficient coding human neuroscience

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Bstj : efficient coding (Oliver, B.M.)

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2016年

Bstj : efficient coding (Oliver, B.M.) by published by

关键词： (oliver, b.m.) bell system binary digits channel channel capacity code code group code groups coding efficient efficient coding encoding message message source messages probability reduced signal signal symbols system technical variable delay

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Image Sensor System With Bio-Inspired efficient coding and Adaptation

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IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2012年第4期6卷 375-384页

作者： Okuno, Hirotsugu Yagi, Tetsuya Osaka Univ Suita Osaka 5650871 Japan

We designed and implemented an image sensor system equipped with three bio-inspired coding and adaptation strategies: logarithmic transform, local average subtraction, and feedback gain control. The system comprises a field-programmable gate array (FPGA), a resistive network, and active pixel sensors (APS), whose light intensity-voltage characteristics are controllable. The system employs multiple time-varying reset voltage signals for APS in order to realize multiple logarithmic intensity-voltage characteristics, which are controlled so that the entropy of the output image is maximized. The system also employs local average subtraction and gain control in order to obtain images with an appropriate contrast. The local average is calculated by the resistive network instantaneously. The designed system was successfully used to obtain appropriate images of objects that were subjected to large changes in illumination.

关键词： Adaptation bio-inspired efficient coding image sensor logarithmic response neuromorphic silicon retina

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Autonomous Development of Active Binocular and Motion Vision Through Active efficient coding

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FRONTIERS IN NEUROROBOTICS 2019年 13卷 49页

作者： Lelais, Alexander Mahn, Jonas Narayan, Vikram Zhang, Chong Shi, Bertram E. Triesch, Jochen Frankfurt Inst Adv Studies Frankfurt Germany Hong Kong Univ Sci & Technol Dept Elect & Comp Engn Kowloon Hong Kong Peoples R China

We present a model for the autonomous and simultaneous learning of active binocular and motion vision. The model is based on the Active efficient coding (AEC) framework, a recent generalization of classic efficient coding theories to active perception. The model learns how to efficiently encode the incoming visual signals generated by an object moving in 3-D through sparse coding. Simultaneously, it learns how to produce eye movements that further improve the efficiency of the sensory coding. This learning is driven by an intrinsic motivation to maximize the system's coding efficiency. We test our approach on the humanoid robot iCub using simulations. The model demonstrates self-calibration of accurate object fixation and tracking of moving objects. Our results show that the model keeps improving until it hits physical constraints such as camera or motor resolution, or limits on its internal coding capacity. Furthermore, we show that the emerging sensory tuning properties are in line with results on disparity, motion, and motion-in-depth tuning in the visual cortex of mammals. The model suggests that vergence and tracking eye movements can be viewed as fundamentally having the same objective of maximizing the coding efficiency of the visual system and that they can be learned and calibrated jointly through AEC.

关键词： autonomous learning active perception binocular vision optokinetic nystagmus smooth pursuit efficient coding intrinsic motivation

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Spatio-Temporally efficient coding Assigns Functions to Hierarchical Structures of the Visual System

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FRONTIERS IN COMPUTATIONAL NEUROSCIENCE 2022年 16卷 890447页

作者： Sihn, Duho Kim, Sung-Phil Ulsan Natl Inst Sci & Technol Dept Biomed Engn Ulsan South Korea

Hierarchical structures constitute a wide array of brain areas, including the visual system. One of the important questions regarding visual hierarchical structures is to identify computational principles for assigning functions that represent the external world to hierarchical structures of the visual system. Given that visual hierarchical structures contain both bottom-up and top-down pathways, the derived principles should encompass these bidirectional pathways. However, existing principles such as predictive coding do not provide an effective principle for bidirectional pathways. Therefore, we propose a novel computational principle for visual hierarchical structures as spatio-temporally efficient coding underscored by the efficient use of given resources in both neural activity space and processing time. This coding principle optimises bidirectional information transmissions over hierarchical structures by simultaneously minimising temporal differences in neural responses and maximising entropy in neural representations. Simulations demonstrated that the proposed spatio-temporally efficient coding was able to assign the function of appropriate neural representations of natural visual scenes to visual hierarchical structures. Furthermore, spatio-temporally efficient coding was able to predict well-known phenomena, including deviations in neural responses to unlearned inputs and bias in preferred orientations. Our proposed spatio-temporally efficient coding may facilitate deeper mechanistic understanding of the computational processes of hierarchical brain structures.

关键词： efficient coding hierarchical structure neural response neural representation receptive field selectivity visual system

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Principal component decomposition of acoustic and neural representations of time-varying pitch reveals adaptive efficient coding of speech covariation patterns

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BRAIN AND LANGUAGE 2022年 230卷 105122页

作者： Llanos, Fernando Gnanateja, G. Nike Chandrasekaran, Bharath Univ Texas Austin Dept Linguist Austin TX 78712 USA Univ Pittsburgh Dept Commun Sci & Disorders Pittsburgh PA 15260 USA 5050 Forbes Tower Pittsburgh PA 15260 USA Robert L Patton Hall 4 730 Austin TX 78712 USA

Understanding the effects of statistical regularities on speech processing is a central issue in auditory neuroscience. To investigate the effects of distributional covariance on the neural processing of speech features, we introduce and validate a novel approach: decomposition of time-varying signals into patterns of covariation extracted with Principal Component Analysis. We used this decomposition to assay the sensory representation of pitch covariation patterns in native Chinese listeners and non-native learners of Mandarin Chinese tones. Sensory representations were examined using the frequency-following response, a far-field potential that reflects phaselocked activity from neural ensembles along the auditory pathway. We found a more efficient representation of the covariation patterns that accounted for more redundancy in the form of distributional covariance. Notably, long-term language and short-term training experiences enhanced the sensory representation of these covariation patterns.

关键词： Principal component analysis Lexical tones Frequency following response efficient coding Statistical learning Speech perception

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