scholarly journals Neural Coding of Spatial Phase in V1 of the Macaque Monkey

2003 ◽  
Vol 89 (6) ◽  
pp. 3304-3327 ◽  
Author(s):  
Dmitriy Aronov ◽  
Daniel S. Reich ◽  
Ferenc Mechler ◽  
Jonathan D. Victor
Keyword(s):  
Metric Space ◽  
Neural Coding ◽  
Macaque Monkey ◽  
Temporal Coding ◽  
Phase Coding ◽  
Spatial Phase ◽  
Novel Approach ◽  
Phase Cycle ◽  
The Times ◽  
Temporal Profiles

We examine the responses of single neurons and pairs of neurons, simultaneously recorded with a single tetrode in the primary visual cortex of the anesthetized macaque monkey, to transient presentations of stationary gratings of varying spatial phase. Such simultaneously recorded neurons tended to have similar tuning to the phase of the grating. To determine the response features that reliably discriminate these stimuli, we use the metric-space approach extended to pairs of neurons. We find that paying attention to the times of individual spikes, at a resolution of ∼30 ms, and keeping track of which neuron fires which spike rather than just the summed local activity contribute substantially to phase coding. The contribution is both quantitative (increasing the fidelity of phase coding) and qualitative (enabling a 2-dimensional “response space” that corresponds to the spatial phase cycle). We use a novel approach, the extraction of “temporal profiles” from the metric space analysis, to interpret and compare temporal coding across neurons. Temporal profiles were remarkably consistent across a large subset of neurons. This consistency indicates that simple mechanisms (e.g., comparing the size of the transient and sustained components of the response) allow the temporal contribution to phase coding to be decoded.

scholarly journals Pseudosparse neural coding in the visual system of primates

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Sidney R. Lehky ◽  
Keiji Tanaka ◽  
Anne B. Sereno
Keyword(s):  
Neural Coding ◽  
Macaque Monkey ◽  
Implicit Assumption ◽  
Data Set ◽  
Efficient Coding ◽  
Population Responses ◽  
Lateral Intraparietal Cortex ◽  
Neural Populations ◽  
Neurophysiological Data ◽  
The Mean

AbstractWhen measuring sparseness in neural populations as an indicator of efficient coding, an implicit assumption is that each stimulus activates a different random set of neurons. In other words, population responses to different stimuli are, on average, uncorrelated. Here we examine neurophysiological data from four lobes of macaque monkey cortex, including V1, V2, MT, anterior inferotemporal cortex, lateral intraparietal cortex, the frontal eye fields, and perirhinal cortex, to determine how correlated population responses are. We call the mean correlation the pseudosparseness index, because high pseudosparseness can mimic statistical properties of sparseness without being authentically sparse. In every data set we find high levels of pseudosparseness ranging from 0.59–0.98, substantially greater than the value of 0.00 for authentic sparseness. This was true for synthetic and natural stimuli, as well as for single-electrode and multielectrode data. A model indicates that a key variable producing high pseudosparseness is the standard deviation of spontaneous activity across the population. Consistently high values of pseudosparseness in the data demand reconsideration of the sparse coding literature as well as consideration of the degree to which authentic sparseness provides a useful framework for understanding neural coding in the cortex.

scholarly journals Neural Coding of Gustatory Information in the Nucleus of the Solitary Tract in Lean and Obese Awake Freely-licking Rats

2019 ◽  
Author(s):  
Michael S Weiss ◽  
Andras Hajnal ◽  
Krzysztof Czaja ◽  
Patricia M Di Lorenzo
Keyword(s):  
Neural Coding ◽  
Nucleus Tractus Solitarius ◽  
Artificial Saliva ◽  
Single Cells ◽  
High Energy ◽  
Temporal Coding ◽  
Ingestive Behavior ◽  
Taste Perception ◽  
Experimental Chamber ◽  
Compensatory Mechanisms

Taste perception changes with obesity but the underlying neural changes remain poorly understood. To address this issue, we recorded taste responses from single cells in the nucleus tractus solitarius (NTS, the fist central synapse in the gustatory circuit) in awake, diet-induced obese [(DIO; ≥8wks on a high-energy diet (HED)] and lean rats. Rats were implanted with a bundle of microelectrodes in the NTS and allowed to recover. Water-deprived rats were allowed to freely lick various tastants in an experimental chamber. Taste stimuli included an array of sapid stimuli dissolved in artificial saliva (AS). Each taste trial consisted of 5 consecutive licks followed by 5 AS licks presented on a VR5 schedule. Results showed that taste responses in NTS cells in DIO rats (n=49) were smaller in magnitude, shorter in duration and longer in latency that those in lean rats (n=74). However, there were proportionately more taste-responsive cells in DIO than in lean rats. Lick coherence in DIO rats was significantly lower than in lean rats, both in taste-responsive and lick-related cells (n=172 in lean; n=65 in DIO). Analyses of temporal coding showed that taste cells in DIO rats conveyed less information about taste quality than cells in lean rats. Collectively, results suggest that a HED produces blunted, but more prevalent, responses to taste in the NTS and a weakened association of taste responses with ingestive behavior. These neural adaptations may represent both negative effects and compensatory mechanisms of a HED that may underlie deficits in taste-related behavior associated with obesity.

scholarly journals Origins of direction selectivity in the primate retina

2021 ◽  
Author(s):  
Yeon Jin Kim ◽  
Beth Peterson ◽  
Joanna Crook ◽  
Hannah Joo ◽  
Jiajia Wu ◽  
...  
Keyword(s):  
Neural Coding ◽  
Amacrine Cell ◽  
Cell Types ◽  
Macaque Monkey ◽  
Direction Selectivity ◽  
Bipolar Cells ◽  
Motion Processing ◽  
Motion Direction ◽  
Motion Sensitivity ◽  
Starburst Amacrine Cell

Abstract From mouse to primate, there is a striking discontinuity in our current understanding of the neural coding of motion direction. In non-primate mammals, directionally selective cell types and circuits are a signature feature of the retina, situated at the earliest stage of the visual process1,2. In primates, by contrast, direction selectivity is a hallmark of motion processing areas in visual cortex3,4, but has not been found in the retina, despite significant effort5,6. Here we combined functional recordings of light-evoked responses and connectomic reconstruction to identify diverse direction-selective cell types in the macaque monkey retina with distinctive physiological properties and synaptic motifs. This circuitry includes an ON-OFF ganglion cell type, a spiking, ON-OFF poly-axonal amacrine cell and the starburst amacrine cell, all of which show direction selectivity. Moreover, we found unexpectedly that macaque starburst cells possess a strong, non-GABAergic, antagonistic surround mediated by input from excitatory bipolar cells that is critical for the generation of radial motion sensitivity in these cells. Our findings open a new door to investigation of a novel circuitry that computes motion direction in the primate visual system.

SMEs Oriented Industrial Alliance

2001 ◽  
Author(s):  
Dong Hongzhao ◽  
Chen Ying ◽  
Yang Canjun ◽  
Huang Jiangyang
Keyword(s):  
Fluid Power ◽  
Application Technology ◽  
Information Platform ◽  
Novel Approach ◽  
Similar Product ◽  
Research Experiment ◽  
Market Areas ◽  
The Times ◽  
Small Medium Enterprises ◽  
Medium Enterprises

Abstract Small-Medium-enterprises (SMEs) occupy a large proportion in modem global economies. However, most SMEs haven’t enough capacities to obtain valuable information and develop new products, thus resulting in a low flexibility to the market. In the times of intellectual globalization economies, while being in competition with powerful rival such as large corporation group, how the SMEs could find an effective way to survive today and further develop tomorrow, especially in the developing country, is focused on in this paper. Based on industry catalog, Industrial Alliance, a novel approach was put forward in this paper. Owing to commonwealth information platform, Industrial Alliance is able to assemble SMEs with similar product characteristics and market areas to enhance their competitiveness. In this paper, enterprise behavior protocol is proposed concerning forging alliance among SMEs. Moreover, the systematic architecture of Industrial Alliance is mainly depicted in order to image the whole profile of Industrial Alliance, including the essential principle, support application technology coupled with collaboration activities. At last, take the fluid power trade for an example, the practical research experiment of the information system for China fluid power (Including hydraulic and pneumatic products) Industrial Alliance is illustrated.

Efficient Feedback Design for Spatial Phase Coding in MISO-OFDM Systems

2011 ◽  
Vol E94-B (7) ◽  
pp. 2149-2152 ◽  
Author(s):  
Jeong-Chul SHIN ◽  
Jee-Hoon KIM ◽  
Hyoung-Kyu SONG
Keyword(s):  
Ofdm Systems ◽  
Phase Coding ◽  
Spatial Phase ◽  
Feedback Design

Chaos and neural coding: Is the binding problem a pseudo-problem?

2001 ◽  
Vol 24 (5) ◽  
pp. 826-827 ◽  
Author(s):  
Antonino Raffone ◽  
Cees van Leeuwen
Keyword(s):  
Neural Coding ◽  
Temporal Coding ◽  
Binding Problem ◽  
Holistic View ◽  
Brain Functions ◽  
Visual Scenes ◽  
Thoughtful Discussion ◽  
Formal Properties

Tsuda's article suggests several plausible concepts of neurodynamic representation and processing, with a thoughtful discussion of their neurobiological grounding and formal properties. However, Tsuda's theory leads to a holistic view of brain functions and to the controversial conclusion that the “binding problem” is a pseudo-problem. By contrast, we stress the role of chaotic patterns in solving the binding problem, in terms of flexible temporal coding of visual scenes through graded and intermittent synchrony.

scholarly journals Exploring the Relation Between Co-changes and Architectural Smells

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Darius Sas ◽  
Paris Avgeriou ◽  
Ronald Kruizinga ◽  
Ruben Scheedler
Keyword(s):  
Open Source ◽  
State Of The Art ◽  
Statistical Tests ◽  
Trade Offs ◽  
Novel Approach ◽  
Multiple Case ◽  
Research Questions ◽  
Low Levels ◽  
The Times

AbstractThe interplay between Maintainability and Reliability can be particularly complex and different kinds of trade-offs may arise when developers try to optimise for either one of these two qualities. To further understand how Maintainability and Reliability influence each other, we perform an empirical study using architectural smells and source code file co-changes as proxies for these two qualities, respectively. The study is designed using an exploratory multiple-case case study following well-know guidelines and using fourteen open source Java projects. Three different research questions are identified and investigated through statistical analysis. Co-changes are detected by using both a state-of-the-art algorithm and a novel approach. The three architectural smells selected are among the most important from the literature and are detected using open source tools. The results show that 50% of co-changes eventually end up taking part in an architectural smell. Moreover, statistical tests indicate that in 50% of the projects, files and packages taking part in smells are more likely to co-change than non-smelly files. Finally, co-changes were also found to appear before smells 90% of the times a smell and a co-change appear in the same file pair. Our findings show that Reliability is indirectly affected by low levels of Maintainability even at the architectural level. This is because low-quality components require more frequent changes by the developers, increasing chances to eventually introduce faults.

scholarly journals Molecular Mechanisms of Neurotransmitter Release Control Distinct Features of Sensory Coding Reliability

2021 ◽  
Author(s):  
Eyal Rozenfeld ◽  
Nadine Ehmann ◽  
Julia E. Manoim ◽  
Robert J. Kittel ◽  
Moshe Parnas
Keyword(s):  
Neurotransmitter Release ◽  
Action Potentials ◽  
Neural Coding ◽  
Information Transfer ◽  
Molecular Mechanisms ◽  
Neural Code ◽  
Temporal Coding ◽  
Neural Representation ◽  
Major Mechanism

AbstractA key requirement for the repeated identification of a stimulus is a reliable neural representation each time it is encountered. Neural coding is often considered to rely on two major coding schemes: the firing rate of action potentials, known as rate coding, and the precise timing of action potentials, known as temporal coding. Synaptic transmission is the major mechanism of information transfer between neurons. While theoretical studies have examined the effects of neurotransmitter release probability on neural code reliability, it has not yet been addressed how different components of the release machinery affect coding of physiological stimuli in vivo. Here, we use the first synapse of the Drosophila olfactory system to show that the reliability of the neural code is sensitive to perturbations of specific presynaptic proteins controlling distinct stages of neurotransmitter release. Notably, the presynaptic manipulations decreased coding reliability of postsynaptic neurons only at high odor intensity. We further show that while the reduced temporal code reliability arises from monosynaptic effects, the reduced rate code reliability arises from circuit effects, which include the recruitment of inhibitory local neurons. Finally, we find that reducing neural coding reliability decreases behavioral reliability of olfactory stimulus classification.

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