Shifting Spike Times or Adding and Deleting Spikes—How Different Types of Noise Shape Signal Transmission in Neural Populations

The responses of high-level neurons tend to be mixtures of many different types of signals. While this diversity is thought to allow for flexible neural processing, it presents a challenge for understanding how neural responses relate to task performance and to neural computation. To address these challenges, we have developed a new method to parse the responses of individual neurons into weighted sums of intuitive signal components. Our method computes the weights by projecting a neuron's responses onto a predefined orthonormal basis. Once determined, these weights can be combined into measures of signal modulation; however, in their raw form these signal modulation measures are biased by noise. Here we introduce and evaluate two methods for correcting this bias, and we report that an analytically derived approach produces performance that is robust and superior to a bootstrap procedure. Using neural data recorded from inferotemporal cortex and perirhinal cortex as monkeys performed a delayed-match-to-sample target search task, we demonstrate how the method can be used to quantify the amounts of task-relevant signals in heterogeneous neural populations. We also demonstrate how these intuitive quantifications of signal modulation can be related to single-neuron measures of task performance ( d′).

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Assessing Short‐Term Clock Errors and Drifts of Temporary Seismic Networks Using the Active Airgun Source in Binchuan, Yunnan

Seismological Research Letters ◽

10.1785/0220190098 ◽

2019 ◽

Vol 90 (6) ◽

pp. 2165-2174 ◽

Cited By ~ 1

Author(s):

Jinzhong Jiang ◽

Runhai Yang ◽

Bin Wang ◽

Ya Xiang ◽

Weidong Pang ◽

...

Keyword(s):

Seismic Data ◽

Matched Filter ◽

Signal Transmission ◽

P Wave ◽

Filter Method ◽

Short Term ◽

Hardware Failure ◽

Different Types ◽

Station Pair ◽

Seismic Networks

ABSTRACT We conducted a short‐term airgun experiment at the Binchuan Fixed Airgun Signal Transmission Station from 14 to 20 February 2017, and two different types of seismometers (Güralp CMG‐40T and QS05A) recorded 62 airgun shots triggered under the same conditions. However, we observed significant clock errors and drifts in seismic data recorded by four QS05A seismometers. To assess the short‐term clock errors and drifts for seismometers, we propose a new method that measures the P‐wave arrival‐time differences between airgun signals recorded at a station pair, using the matched filter method. We find ∼1.0 s absolute clock errors for two Güralp CMG‐40T stations (CKT2 and 53261) and one QS05A station (STA05), as well as ∼0.5 s timing leaps for four QS05A stations (STA19, STA21, STA31, and STA33) during the experiment. Furthermore, all the QS05A seismometers exhibit clock drifts with similar linear trends. Additionally, we use teleseismic waveforms to verify the absolute clock errors for stations CKT2, 53261, and STA05. After double‐checking several possible factors, we determine the hardware failure or malfunctioning that may cause clock errors for the two types of seismometers.

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Comparative Study of DDS with Different Types of Phase Accumulators

Inventions ◽

10.3390/inventions4030035 ◽

2019 ◽

Vol 4 (3) ◽

pp. 35

Author(s):

Oleksiy Polikarovskykh ◽

Lesia Karpova ◽

Ihor Hula ◽

Vasyl Melnychuk

Keyword(s):

Signal Transmission ◽

Block Length ◽

Maximum Output ◽

Output Frequency ◽

Direct Digital Synthesizer ◽

Transfer Delay ◽

Variable Block ◽

Different Types ◽

Parallel Transfer ◽

Transfer Signal

The paper deals with the problems of delayed transfer signals in the direct digital synthesizer (DDS) phase accumulator adders. Transfer delay is one of the factors that affect the maximum output frequency of the DDS synthesizer. The main types of adders used in DDS synthesizers are described. Separately, attention was paid to the adder with a consistent transfer of the transfer signal, adders with a transmission carry signal with a fixed block length, adders with a signal transmission delay with a variable block length, and a mathematical analysis of the origin and duration of the delay of the transfer signal in them. It was found that the use of a transfer adder with a variable length of a block in the core of a direct digital synthesizer would increase the maximum output frequency by 2.4 times compared to the adder with a parallel transfer, and by 1.43 times as compared with the adder with a fixed length the block.

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Transmission delays and frequency detuning can regulate information flow between brain regions

10.1101/2020.07.09.194969 ◽

2020 ◽

Author(s):

Aref Pariz ◽

Ingo Fischer ◽

Alireza Valizadeh ◽

Claudio Mirasso

Keyword(s):

Functional Connectivity ◽

Information Transfer ◽

Effective Connectivity ◽

Signal Transmission ◽

Brain Networks ◽

Frequency Detuning ◽

Brain Oscillations ◽

Brain Areas ◽

Neural Populations

AbstractBrain networks exhibit very variable and dynamical functional connectivity and flexible configurations of information exchange despite their overall fixed structure (connectome). Brain oscillations are hypothesized to underlie time-dependent functional connectivity by periodically changing the excitability of neural populations. In this paper, we investigate the role that the connection delay and the frequency detuning between different neural populations play in the transmission of signals. Based on numerical simulations and analytical arguments, we show that the amount of information transfer between two oscillating neural populations can be determined solely by their connection delay and the mismatch in their oscillation frequencies. Our results highlight the role of the collective phase response curve of the oscillating neural populations for the efficacy of signal transmission and the quality of the information transfer in brain networks.Author summaryCollective dynamics in brain networks is characterized by a coordinated activity of their constituent neurons that lead to brain oscillations. Many evidences highlight the role that brain oscillations play in signal transmission, the control of the effective communication between brain areas and the integration of information processed by different specialized regions. Oscillations periodically modulate the excitability of neurons and determine the response those areas receiving the signals. Based on the communication trough coherence (CTC) theory, the adjustment of the phase difference between local oscillations of connected areas can specify the timing of exchanged signals and therefore, the efficacy of the communication channels. An important factor is the delay in the transmission of signals from one region to another that affects the phase difference and timing, and consequently the impact of the signals. Despite this delay plays an essential role in CTC theory, its role has been mostly overlooked in previous studies. In this manuscript, we concentrate on the role that the connection delay and the oscillation frequency of the populations play in the signal transmission, and consequently in the effective connectivity, between two brain areas. Through extensive numerical simulations, as well as analytical results with reduced models, we show that these parameters have two essential impacts on the effective connectivity of the neural networks: First, that the populations advancing in phase to others do not necessarily play the role of the information source; and second, that the amount and direction of information transfer dependents on the oscillation frequency of the populations.

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Transmission delays and frequency detuning can regulate information flow between brain regions

PLoS Computational Biology ◽

10.1371/journal.pcbi.1008129 ◽

2021 ◽

Vol 17 (4) ◽

pp. e1008129

Author(s):

Aref Pariz ◽

Ingo Fischer ◽

Alireza Valizadeh ◽

Claudio Mirasso

Keyword(s):

Functional Connectivity ◽

Information Exchange ◽

Information Transfer ◽

Phase Response Curve ◽

Signal Transmission ◽

Brain Networks ◽

Brain Regions ◽

Transmission Delays ◽

Neural Populations

Brain networks exhibit very variable and dynamical functional connectivity and flexible configurations of information exchange despite their overall fixed structure. Brain oscillations are hypothesized to underlie time-dependent functional connectivity by periodically changing the excitability of neural populations. In this paper, we investigate the role of the connection delay and the detuning between the natural frequencies of neural populations in the transmission of signals. Based on numerical simulations and analytical arguments, we show that the amount of information transfer between two oscillating neural populations could be determined by their connection delay and the mismatch in their oscillation frequencies. Our results highlight the role of the collective phase response curve of the oscillating neural populations for the efficacy of signal transmission and the quality of the information transfer in brain networks.

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Ubiquitin signals in the NF-κB pathway

Biochemical Society Transactions ◽

10.1042/bst0350942 ◽

2007 ◽

Vol 35 (5) ◽

pp. 942-945 ◽

Cited By ~ 23

Author(s):

J. Terzic ◽

I. Marinovic-Terzic ◽

F. Ikeda ◽

I. Dikic

Keyword(s):

Molecular Basis ◽

Signal Transmission ◽

Control Cell ◽

Adaptive Immune Response ◽

Nuclear Factor Κb ◽

Nuclear Factor ◽

Post Translational Modifications ◽

Adaptive Immune ◽

Different Types ◽

Response Post

The NF-κB (nuclear factor κB) transcription factors control cell survival, proliferation and innate and adaptive immune response. Post-translational modifications of key components of the NF-κB pathway provide the molecular basis for signal transmission from the cell membrane to the nucleus. Here, we describe the involvement of different types of ubiquitin modification in the regulation of the NF-κB signalling pathway.

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On the use of envelope following responses to estimate peripheral level compression in the auditory system

Scientific Reports ◽

10.1038/s41598-021-85850-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Gerard Encina-Llamas ◽

Torsten Dau ◽

Bastian Epp

Keyword(s):

Auditory Nerve ◽

Basilar Membrane ◽

Complementary Information ◽

Distortion Product ◽

Hearing Thresholds ◽

Neural Populations ◽

Different Types ◽

Cochlear Damage ◽

Envelope Following Response ◽

Cochlear Compression

AbstractIndividual estimates of cochlear compression may provide complementary information to traditional audiometric hearing thresholds in disentangling different types of peripheral cochlear damage. Here we investigated the use of the slope of envelope following response (EFR) magnitude-level functions obtained from four simultaneously presented amplitude modulated tones with modulation frequencies of 80–100 Hz as a proxy of peripheral level compression. Compression estimates in individual normal hearing (NH) listeners were consistent with previously reported group-averaged compression estimates based on psychoacoustical and distortion-product oto-acoustic emission (DPOAE) measures in human listeners. They were also similar to basilar membrane (BM) compression values measured invasively in non-human mammals. EFR-based compression estimates in hearing-impaired listeners were less compressive than those for the NH listeners, consistent with a reduction of BM compression. Cochlear compression was also estimated using DPOAEs in the same NH listeners. DPOAE estimates were larger (less compressive) than EFRs estimates, showing no correlation. Despite the numerical concordance between EFR-based compression estimates and group-averaged estimates from other methods, simulations using an auditory nerve (AN) model revealed that compression estimates based on EFRs might be highly influenced by contributions from off-characteristic frequency (CF) neural populations. This compromises the possibility to estimate on-CF (i.e., frequency-specific or “local”) peripheral level compression with EFRs.

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The extinction time of a general birth and death process with catastrophes

Journal of Applied Probability ◽

10.1017/s0021900200116031 ◽

1986 ◽

Vol 23 (04) ◽

pp. 851-858 ◽

Cited By ~ 1

Author(s):

P. J. Brockwell

Keyword(s):

Laplace Transform ◽

Size Distribution ◽

Sufficient Conditions ◽

Necessary And Sufficient Conditions ◽

Death Process ◽

Extinction Time ◽

Birth And Death Process ◽

Different Types ◽

The Laplace Transform ◽

Necessary And Sufficient

The Laplace transform of the extinction time is determined for a general birth and death process with arbitrary catastrophe rate and catastrophe size distribution. It is assumed only that the birth rates satisfyλ0= 0,λj> 0 for eachj> 0, and. Necessary and sufficient conditions for certain extinction of the population are derived. The results are applied to the linear birth and death process (λj=jλ, µj=jμ) with catastrophes of several different types.

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Differentiating between different forms of moral obligations

Behavioral and Brain Sciences ◽

10.1017/s0140525x19002589 ◽

2020 ◽

Vol 43 ◽

Author(s):

Rajen A. Anderson ◽

Benjamin C. Ruisch ◽

David A. Pizarro

Keyword(s):

Moral Character ◽

Moral Obligations ◽

Different Types

Abstract We argue that Tomasello's account overlooks important psychological distinctions between how humans judge different types of moral obligations, such as prescriptive obligations (i.e., what one should do) and proscriptive obligations (i.e., what one should not do). Specifically, evaluating these different types of obligations rests on different psychological inputs and has distinct downstream consequences for judgments of moral character.

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Ultrastructural Investigations of the Contractile Filaments of Amoebae

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050950 ◽

1974 ◽

Vol 32 ◽

pp. 188-189

Author(s):

P.L. Moore

Keyword(s):

Cytoplasmic Streaming ◽

Three Dimensional ◽

Freeze Fracture ◽

Amoeboid Movement ◽

Different Types ◽

Chemical Conditions ◽

Complete Interpretation

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.

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