scholarly journals Does spike synchrony provide a better code of stimulus angle than average firing rate?

2010 ◽  
Vol 6 (6) ◽  
pp. 66-66 ◽  
Author(s):  
W. J. Jermakowicz ◽  
X. Chen ◽  
I. Khaytin ◽  
Z. Zhou ◽  
M. Bernard ◽  
...  
Keyword(s):  
Firing Rate ◽  
Average Firing Rate ◽  
Spike Synchrony ◽  
Stimulus Angle

Lévy noise-induced inverse stochastic resonance on Newman–Watts networks of Hodgkin–Huxley neurons

2020 ◽  
Vol 34 (19) ◽  
pp. 2050185
Author(s):  
Dongxi Li ◽  
Shuling Song ◽  
Ni Zhang
Keyword(s):  
Firing Rate ◽  
Stochastic Resonance ◽  
Neuronal Network ◽  
Coupling Strength ◽  
Stability Index ◽  
Neuronal Firing ◽  
Lévy Noise ◽  
Neuron Network ◽  
Average Firing Rate ◽  
Levy Noise

This paper primarily investigates the inverse stochastic resonance (ISR) of neuron network driven by Lévy noise with electrical autapse and chemical autapse, respectively. Firstly, the discharge of Hodgkin–Huxley (HH) neuron network under different noise parameters, autapse parameters and network coupling strength is shown. Then, the variation of average firing rate with Lévy noise in the case of electrical autapse and chemical autapse is presented. We find that there exists a minimum value of the average firing rate curve caused by stability index and noise intensity of Lévy noise across the whole network, which is the phenomenon of ISR. With the increase of autaptic intensity and coupling strength, the ISR inhibitory effect of neuron discharge is weakened. In addition, with the increase of coupling strength, the neuron discharge of neural network is more intense and regular. As a consequence, our work suggests that autaptic intensity and coupling efficient of neuronal network can regulate the neuronal firing activities and suppress the effect of ISR, and Lévy noise can induce ISR phenomenon in Newman–Watts neuronal network.

Neural Ensemble Coding during Working Memory Task in Rat Prefrontal Cortex

2011 ◽  
Vol 467-469 ◽  
pp. 1291-1296
Author(s):  
Wen Wen Bai ◽  
Xin Tian
Keyword(s):  
Working Memory ◽  
Prefrontal Cortex ◽  
Firing Rate ◽  
Memory Task ◽  
Neural Population ◽  
Average Firing Rate ◽  
Population Activity ◽  
Ensemble Coding ◽  
Neural Ensemble ◽  
Ensemble Activity

Working memory is one of important cognitive functions and recent studies demonstrate that prefrontal cortex plays an important role in working memory. But the issue that how neural activity encodes during working memory task is still a question that lies at the heart of cognitive neuroscience. The aim of this study is to investigate neural ensemble coding mechanism via average firing rate during working memory task. Neural population activity was measured simultaneously from multiple electrodes placed in prefrontal cortex while rats were performing a working memory task in Y-maze. Then the original data was filtered by a high-pass filtering, spike detection and spike sorting, spatio-temporal trains of neural population were ultimately obtained. Then, the average firing rates were computed in a selected window (500ms) with a moving step (125ms). The results showed that the average firing rate were higher during workinig memory task, along with obvious ensemble activity. Conclusion: The results indicate that the working memory information is encoded with neural ensemble activity.

Envelope Coding in the Lateral Superior Olive. III. Comparison With Afferent Pathways

1998 ◽  
Vol 79 (1) ◽  
pp. 253-269 ◽  
Author(s):  
Philip X. Joris ◽  
Tom C. T. Yin
Keyword(s):  
Firing Rate ◽  
Auditory Nerve ◽  
Modulation Frequency ◽  
Nerve Fibers ◽  
Cell Populations ◽  
Average Firing Rate ◽  
Afferent Pathways ◽  
Lateral Superior Olive ◽  
Superior Olive ◽  
Auditory Nerve Fibers

Joris, Philip X. and Tom C. T. Yin. Envelope coding in the lateral superior olive. III. Comparison with afferent pathways. J. Neurophysiol. 79: 253–269, 1998. Binaural cues for spatial localization of complex high-frequency sounds are interaural level and time differences (ILDs and ITDs). We previously showed that cells in the lateral superior olive (LSO) are sensitive to ITDs in the envelope of sinusoidally amplitude-modulated (AM) signals up to a modulation frequency of only ∼800 Hz. To understand the limitations in this ITD-sensitivity, we here compare responses to monaural modulation in LSO and its input pathways, derived from cochlear nucleus and medial nucleus of the trapezoid body. These pathways have marked functional and morphological specializations, suggestive of adaptations for timing. Afferent cell populations were identified on the basis of electrophysiological signatures, and for each population, average firing rate and synchronization to AM tones were compared with auditory-nerve fibers and LSO cells. Except for an increase in modulation gain in some subpopulations, synchronization of LSO afferents was very similar to that in auditory nerve fibers in its dependency on sound pressure level (SPL), modulation depth, and modulation frequency. Distributions of cutoff frequencies of modulation transfer functions were largely coextensive with the distribution in auditory nerve. Group delays, measured from the phase of the response modulation as a function of modulation frequency, showed an orderly dependence on characteristic frequency and cell type and little dependence on SPL. Similar responses were obtained to a modulated broadband carrier. Compared with their afferents, LSO cells synchronized to monaurally modulated stimuli with a higher gain but often over a narrower range of modulation frequencies. Considering the scatter in afferent and LSO cell populations, ipsi- and contralateral responses were well matched in cutoff frequency and magnitude of delays. In contrast to their afferents, LSO cells show a decrease in average firing rate at high modulation frequencies. We conclude that the restricted modulation frequency range over which LSO cells show ITD-sensitivity does not result from loss of envelope information along the afferent pathway but is due to convergence or postsynaptic effects at the level of the LSO. The faithful transmission of envelope phase-locking in LSO afferents is consistent with their physiological and morphological adaptations, but these adaptations are not commensurate with the rather small effects of physiological ITDs reported previously, especially when compared with effects of ILDs. We suggest that these adaptations have evolved to allow a comparison of instantaneous amplitude fluctuations at the two ears rather than to extract interaural timing information per se.

scholarly journals Hidden Markov Models Predict the Future Choice Better Than a PSTH-Based Method

2019 ◽  
Vol 31 (9) ◽  
pp. 1874-1890 ◽  
Author(s):  
Encarni Marcos ◽  
Fabrizio Londei ◽  
Aldo Genovesio
Keyword(s):  
Firing Rate ◽  
Hidden Markov Models ◽  
Neural Activity ◽  
Markov Models ◽  
Hidden Markov ◽  
Experimental Session ◽  
Average Firing Rate ◽  
Action Execution ◽  
Neural Recordings ◽  
Neuronal Ensembles

Beyond average firing rate, other measurable signals of neuronal activity are fundamental to an understanding of behavior. Recently, hidden Markov models (HMMs) have been applied to neural recordings and have described how neuronal ensembles process information by going through sequences of different states. Such collective dynamics are impossible to capture by just looking at the average firing rate. To estimate how well HMMs can decode information contained in single trials, we compared HMMs with a recently developed classification method based on the peristimulus time histogram (PSTH). The accuracy of the two methods was tested by using the activity of prefrontal neurons recorded while two monkeys were engaged in a strategy task. In this task, the monkeys had to select one of three spatial targets based on an instruction cue and on their previous choice. We show that by using the single trial's neural activity in a period preceding action execution, both models were able to classify the monkeys' choice with an accuracy higher than by chance. Moreover, the HMM was significantly more accurate than the PSTH-based method, even in cases in which the HMM performance was low, although always above chance. Furthermore, the accuracy of both methods was related to the number of neurons exhibiting spatial selectivity within an experimental session. Overall, our study shows that neural activity is better described when not only the mean activity of individual neurons is considered and that therefore, the study of other signals rather than only the average firing rate is fundamental to an understanding of the dynamics of neuronal ensembles.

Projection neurons of the lateral amygdaloid nucleus are virtually silent throughout the sleep--waking cycle

1996 ◽  
Vol 75 (3) ◽  
pp. 1301-1305 ◽  
Author(s):  
H. Gaudreau ◽  
D. Pare
Keyword(s):  
Firing Rate ◽  
Slow Wave Sleep ◽  
Paradoxical Sleep ◽  
Discharge Rate ◽  
Projection Neurons ◽  
Amygdaloid Nucleus ◽  
Average Firing Rate ◽  
Sensory Stimuli ◽  
Firing Rates ◽  
Lateral Nucleus

1. Amygdala neurons were recorded extracellularly during the sleep-waking cycle in chronically implanted cats. Neurons were identified as projection cells when they could be antidromically invaded from the perirhinal and/or entorhinal cortices. 2. In contrast with other nuclei of the amygdala, few spontaneously active neurons were encountered in the lateral nucleus. However, when hunting stimuli were applied to the parahippocampal cortices, we noticed the presence of numerous projection cells that would have otherwise remained undetected because they had little or no spontaneous activity. 3. In the states of waking, slow-wave sleep, and paradoxical sleep, the discharge rate of antidromically invaded neurons averaged 0.09 +/- 0.07 Hz (mean +/- SE) with 82% of cells firing at < 0.01 Hz in all states. However, they transiently increased their firing rate when cats were presented complex sensory stimuli, which apparently were specific to each cell. In contrast to projection cells, spontaneously active neurons of the lateral nucleus that could not be backfired from the parahippocampal cortices had an average firing rate of 4.34 +/- 1.15 Hz with 38% of cells firing at > or = 6 Hz in at least one state. 4. These results on the extremely low firing rates of identified projection cells suggest that previous extracellular studies of lateral amygdaloid neurons were biased toward a class of spontaneously active cells which probably includes local-circuit cells.

scholarly journals Role of the Primate Superior Colliculus in the Control of Head Movements

2007 ◽  
Vol 98 (4) ◽  
pp. 2022-2037 ◽  
Author(s):  
Mark M. G. Walton ◽  
Bernard Bechara ◽  
Neeraj J. Gandhi
Keyword(s):  
Superior Colliculus ◽  
Firing Rate ◽  
Head Movements ◽  
Neural Basis ◽  
Average Firing Rate ◽  
Gaze Shifts ◽  
Burst Neurons ◽  
The Gaze ◽  
Head Displacement ◽  
Elevated Frequency

One important behavioral role for head movements is to assist in the redirection of gaze. However, primates also frequently make head movements that do not involve changes in the line of sight. Virtually nothing is known about the neural basis of these head-only movements. In the present study, single-unit extracellular activity was recorded from the superior colliculus while monkeys performed behavioral tasks that permit the temporal dissociation of gaze shifts and head movements. We sought to determine whether superior colliculus contains neurons that modulate their activity in association with head movements in the absence of gaze shifts and whether classic gaze-related burst neurons also discharge for head-only movements. For 26% of the neurons in our sample, significant changes in average firing rate could be attributed to head-only movements. Most of these increased their firing rate immediately prior to the onset of a head movement and continued to discharge at elevated frequency until the offset of the movement. Others discharged at a tonic rate when the head was stable and decreased their activity, or paused, during head movements. For many putative head cells, average firing rate was found to be predictive of head displacement. Some neurons exhibited significant changes in activity associated with gaze, eye-only, and head-only movements, although none of the gaze-related burst neurons significantly modulated its activity in association with head-only movements. These results suggest the possibility that the superior colliculus plays a role in the control of head movements independent of gaze shifts.

scholarly journals The primate subthalamic nucleus. II. Neuronal activity in the MPTP model of parkinsonism

1994 ◽  
Vol 72 (2) ◽  
pp. 507-520 ◽  
Author(s):  
H. Bergman ◽  
T. Wichmann ◽  
B. Karmon ◽  
M. R. DeLong
Keyword(s):  
Firing Rate ◽  
Subthalamic Nucleus ◽  
Neuronal Activity ◽  
Low Frequency ◽  
Oscillatory Activity ◽  
Autocorrelation Analysis ◽  
Periodic Activity ◽  
Average Firing Rate ◽  
Mptp Treatment ◽  
Highly Correlated

1. The neuronal mechanisms underlying the major motor signs of Parkinson's disease were studied in the basal ganglia of parkinsonian monkeys. Three African green monkeys were systemically treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) until parkinsonian signs, including akinesia, rigidity, and a prominent 4- to 8-Hz tremor, appeared. The activity of neurons in the subthalamic nucleus (STN) and in the internal segment of the globus pallidus (GPi) was recorded before (STN, n = 220 cells; GPi, n = 175 cells) and after MPTP treatment (STN, n = 326 cells; GPi, n = 154 cells). 2. In STN the spontaneous firing rate was significantly increased from 19 +/- 10 (SD) spikes/s before to 26 +/- 15 spikes/s after MPTP treatment. Division of STN neurons recorded after MPTP treatment into cells with rhythmic bursts of discharge occurring at 4–8 Hz (as defined by autocorrelation analysis) and neurons without 4- to 8-Hz periodic activity revealed an even more prominent increase in the firing rate of the 4- to 8-Hz oscillatory neurons. 3. In GPi overall changes in the average firing rate of cells were inconsistent between different animals and behavioral states. However, the average firing rate of the subpopulation of neurons with 4- to 8-Hz periodic oscillatory activity after treatment with MPTP was significantly increased over that of all neurons before MPTP treatment (from 53 to 76 spikes/s, averaged across monkeys). 4. In the normal state the percentage of neurons with burst discharges (as defined by autocorrelation analysis) was 69% and 78% in STN and GPi, respectively. After MPTP treatment the percentage of cells that discharged in bursts was increased to 79% and 89%, respectively. At the same time the average burst duration decreased (from 121 +/- 98 to 81 +/- 99 ms in STN and from 213 +/- 120 to 146 +/- 134 ms in GPi) with no significant change in the average number of spikes per burst. 5. Periodic oscillatory neuronal activity at low frequency, highly correlated with tremor, was detected in a large number of cells in STN and GPi after MPTP treatment (average oscillation frequency 6.0 and 5.1 Hz, respectively). The autocorrelograms of spike trains of these neurons confirm that the periodic oscillatory activity was very stable. The percentage of cells with 4- to 8-Hz periodic activity significantly increased from 2% to 16% in STN and from 0.6% to 25% in GPi with the MPTP treatment.(ABSTRACT TRUNCATED AT 400 WORDS)

Distinguishing the effects of firing rate co-modulation and excess spike synchrony on the spike–LFP relationship

2010 ◽  
Vol 68 ◽  
pp. e438
Author(s):  
Michael Denker ◽  
Alexa Riehle ◽  
Markus Diesmann ◽  
Sonja Grün
Keyword(s):  
Firing Rate ◽  
Spike Synchrony

Average firing rate of a neural network with dynamical disorder

1995 ◽  
Vol 28 (9) ◽  
pp. 2457-2469 ◽  
Author(s):  
P C Bressloff
Keyword(s):  
Neural Network ◽  
Firing Rate ◽  
Average Firing Rate ◽  
Dynamical Disorder
Sign in / Sign up

Export Citation Format

Share Document