• <tr id="yyy80"></tr>
  • <sup id="yyy80"></sup>
  • <tfoot id="yyy80"><noscript id="yyy80"></noscript></tfoot>
  • 99热精品在线国产_美女午夜性视频免费_国产精品国产高清国产av_av欧美777_自拍偷自拍亚洲精品老妇_亚洲熟女精品中文字幕_www日本黄色视频网_国产精品野战在线观看 ?

    Control of firing activities in thermosensitive neuron by activating excitatory autapse?

    2021-10-28 06:59:48YingXu徐瑩andJunMa馬軍
    Chinese Physics B 2021年10期
    關(guān)鍵詞:馬軍

    Ying Xu(徐瑩) and Jun Ma(馬軍)

    1School of Mathematics and Statistics,Shandong Normal University,Ji’nan 250014,China

    2Department of Physics,Lanzhou University of Technology,Lanzhou 730050,China

    3School of Science,Chongqing University of Posts and Telecommunications,Chongqing 430065,China

    Keywords: thermosensitive neuron,autapse,firing pattern,bifurcation

    1. Introduction

    The brain contains many function regions due to the diversity in function of neurons and connections to astrocytes.The reveal of the mystery of cognitive neural principles in the brain can provide a good insight into the potential mechanism for information transmission, encoding and processing by exploring the dynamics of neural activities in the brain.Therefore,it is critical to obtain a reliable biophysical neuron model,[1–3]and thus the effect of anatomic structure,biophysical activities can be considered completely. Besides the conventional physiological experiments,the brain function imaging, reliable theoretical analysis and numerical approach are effective to judge the information transmission and processing in nervous systems. Neurons are the basic unit for information processing in brain and different biophysical functions are trained and enhanced in different neurons. Most of the neurons have the intrinsic properties such as excitement and conduction,and thus external stimulus can be encoded and propagated between neurons. Within most of the generic neuron models, bifurcation parameters, and external forcing current can be adjusted to trigger different firing patterns and mode selection in the neural activities.[4–8]Also, external stimuli can be used to detect possible occurrence of nonlinear resonance(stochastic resonance and coherence resonance).[9–13]Furthermore, these neuron oscillators are often used to build neural network with different topologies,and the collective behaviors such as wave propagation and stability,pattern formation,synchronization stability can be further investigated.[14–17]The network can present regular spatial distribution under selforganization by taming the local kinetics and coupling channels in the network. On the other hand, many nonlinear circuits can be tamed to reproduce similar firing patterns generated from biological neurons,and thus neural circuits[18–21]are obtained. When more functional electronic components such as memristor, Josephson junction, thermistor, phototube are incorporated into the neural circuits, they can be tamed to percept the effect of field memory, magnetic field, temperature, and external optical illumination by generating equivalent channel current across these functional components.[22–25]As a result, the involvement of more functional components in the artificial network composed of micro neural circuits throws light on the realization and application of intelligence and treatment in nervous disease by repairing neural pathways with auxiliary neural network.

    Synapse can receive,encode and propagate electric signal effectively. Electric synapse can be activated to establish the connection between neurons and gap junction coupling,[26,27]and the synaptic current is changed rapidly to balance the membrane potential. Chemical synapse changes its synaptic current when the neurotransmitter is released, and biologists claimed that chemical synapses[28–31]play main roles in signal exchange and propagation between neurons. From physical viewpoint,electric synapse coupling is similar to the voltage coupling via resistor connection,the gap junction between synapses can generate equivalent resistance as resistor. While chemical synapse coupling can induce field coupling[32–34]during the release and propagation of extracellular and intracellular ions of the cell. When more neurons are connected to build networks, electric synapse, chemical synapse and even hybrid synapse can be activated to couple neurons for estimating the synchronization stability,wave propagation and pattern selection. Autapse is a specific synapse,[35]which reconnects its body or muscle,and it is claimed that the formation of autapse results from self-healing in injured neurons by building an auxiliary loop.[36]Such as the firing frequency of spiking behaviors near sub-critical Hopf bifurcation can be reduced by a short-term delayed excitatory autapse. Meanwhile,the study found an abnormal phenomenon, that is, inhibitory autapse can induce the resting state to change into a stable spiking pattern.[37,38]It often takes a certain response period when external stimulus is encoded to change the dynamical behavior of nonlinear oscillators. The involvement of autapse in neurons can introduce time delay,and this additive bifurcation parameter has a distinct effect on the dynamics of neurons connected to autapse.[39]Indeed, the activation of autapse can generate time-delayed feedback and its self-adaption of neurons can be enhanced. Furthermore,local pacing and heterogeneity can be induced to generate continuous pulse, wave fronts and even defects when local area of the neural network is driven by autapses.[40,41]That is, local distribution of autapses can regulate the collective behaviors of neural network by generating stable pulse or wave fronts.

    It is interesting to understand the communication mechanism between finite neurons in order to study the information transmission and information processing in neural networks. The neural firing activities and the chemical activities of synapses between neurons are involved in information processing.[28,29]The neural activities can be identified by resting state subthreshold oscillation,spiking,bursting,and chaotic firing.[42–44]In 1952, Hodgkin and Huxley proposed the famous Hodgkin–Huxley neuron model based on physiological experiments,[1]and then more improved neuron models were further proposed.[45–47]For example, based on the Morris–Lecar neuron model, the half activation potential parameters of the potassium activation curve are determined,and the properties of the membrane can be controlled by changing the value of a single parameter.[2]Recently, the subthreshold vibrational resonance and the superthreshold vibrational resonance in the FitzHugh–Nagumo (FHN) neuron model were investigated.[3]The nervous system makes local heterogeneity in the network due to complex connection graph and diversity in parameters. Therefore, it is a challenge to obtain reliable neuron models so that specific biophysical effects can be estimated and considered. For example, the fractional order model,[48]the electromagnetic radiation driven model,[49]and the light-dependent neural model[50]have been suggested to estimate the memory effect,electromagnetic induction and encoding in visual system under illumination. In particular,the involvement of memristor into the neural circuit can explain the activation of memristive synapse and physical mechanism of field coupling between neurons.[51–53]In fact, the feedback coupling,[4]non-local coupling,[54]time delay,[5–7]and external stimuli[8]can affect the dynamic behaviors of the nonlinear systems. The bifurcation direction and the stability of oscillation state are changed by reducing noise intensity or increasing natural frequency heterogeneity.[55]In the case of synchronization between nonlinear circuits and neurons, the optimization of coupling channels can enhance the synchronization stability. For example, a hybrid synapse is activated to synchronize two Fitzhugh–Nagumo neurons driven by two voltage sources.Moreover,induction coil coupling can benefit the realization of synchronization between two chaotic Chua systems[56]by balancing the energy pumping along the coupling channels.

    The inherent time delay should be considered in the process of information transmission. The response time delay accounts for the delay in encoding external stimuli, while the propagation time delay is generated by the signal transmission between neurons. In fact,some experiments on inter-neurons have proved that time delay can enhance the adaptability of neurons to external stimuli.[57,58]In the neural networks, local dynamics and connection types are important for regulating synchronization stability,and the release of collective behaviors. However, neural energy may be an effective tool for studying the overall behavior of brain activities,[59]and also for using a finite amount of neural energy to obtain the most efficient spatial information representation of the spike positions organized in the available environment.[60]In addition,neural coding and impulsive effects are attractive questions in the field of neurodynamics.[61]For instance, the couplingpair number density is used as the distributed coding mode for neuronal network to study the effects of external stimuli and noise on the dynamics of neuronal oscillator networks.[62]Furthermore,neurons can form various functional connection loops and perform computational functions through synaptic connections.[63]As mentioned above, the autapse is widely found in cerebral cortex, visual cortex, cerebellum, striatum,and hippocampus,[39]and it has a certain effect on the ability of neurons to detect weak signals.In addition,the autaptic current plays a wide role in regulating the discharge rhythm of a single neuron and the nonlinear behavior of the network. The involvement of autapse connection provides some evidences to confirm the bifurcation role of time delay on dynamics of nonlinear systems.[64,65]

    In previous researches the neuronal dynamics was studied at constant temperature. However, membrane potential is not only regulated by external stimuli, but also sensitive to the temperature because of its changes in the activation of ion channels and excitability. The reaction rate of biochemical reaction is affected by temperature,including the activation and inactivation of membrane ion channels, the activation and release of synapses,the release and conduction velocity of nerve impulses.[66]Some evidences have confirmed that the duration of the pulse decreases with the diaphragm temperature increasing.[11]Previous experiments have shown that temperature affects the conversion rate between opening and closing of ion channels,so temperature factor is introduced into the kinetic constants of ion channels.[67]Braunet al.[68]proposed a thermosensitive neuron model that mimics all spike train patterns observed in electroreceptors from dogfish catfish,and facial cold receptors.Zhaoet al.[69]investigated the BZ reaction oscillation wave from the time-lapse imaging data,embedded the reaction temperature which influences the diffusion coefficient into a pure mathematical model,and finally constructed the temperature dependent FitzHugh–Nagumo model. Furthermore, the authors of this paper ever suggested that thermistor can be incorporated into neural circuits for estimating the temperature effect on mode selection in neural activities. The typical characteristic of thermistor is that the resistance value is sensitive to temperature changes.[70]Coupling the thermistors into a simple FHN neural network circuit enhances the physical function of the circuit. The channel current across the thermistor is changed by the temperature, and it reproduces the main dynamic characteristics of biological neurons by generating different firing patterns.[12]Thermistors can be connected to the appropriate branch in nonlinear circuits and thus its dependence on temperature change[13]can be enhanced Here,both autapse and thermistor are introduced into a simple neural circuit,and the mode selection is explored to know the biophysical processing in neural activities.

    2. Model and scheme

    In 1926, Van der Pol[71]proposed the simplest model,which was derived from the nonlinear relaxation oscillator.Furthermore,Fitzhugh[46]and Nagumoet al.[47]presented its mathematical form of excitable neurons, and its dynamical equations are given as follows:

    wherexandydenote the fast variable and slow variable of the nervous system, respectively, and the dynamics is dependent on the membrane potentialxand recovery variabley;a,b,c,andμare the normalized parameters;Iusis the external forcing current. By adjusting these parameters, the neuron oscillator can be triggered to display quiescent, spiking, bursting, and chaotic firing patterns. This neuron oscillator can be implemented in nonlinear circuit composed of capacitor,inductance coil,constant voltage source,and nonlinear resistor.As is well known,negative temperature coefficient(NTC)thermistor has been found wide applications in temperature measurement,temperature compensation of electronic components, current,and voltage limiters. It is suggested[70]that the NTC thermistor can be used for the synchronization and control of chaotic circuits, and its physical property of temperature dependence is estimated by

    whereRTrepresents the resistance of the thermistor at temperatureT,andRdenotes the nominal resistance of the thermistor at the rated temperatureT2. TheRis considered as a constant at an infinitely high temperatureT2→∞(i.e.,when 1/T2→0).TheBis the thermal index,indicating the material constant of the thermistor, which depends on the ratio of the activation energyqto the Boltzmann constantk. The neural circuit is dependent on the temperature when a linear resistor is replaced by a thermistor. By applying the scaling transformation to the physical variables and parameters for the nonlinear circuit,the temperature-dependent neuron oscillator driven by autapse is obtained by

    The normalized parameterT′=T/T0is a dimensionless temperature variable,whereTis the physical temperature andT0is the room temperature. Based on Eq. (2), the dimensionless parameters can be expressed asμ(T′)=μ0exp(?1/T′),Ius(T′)=Iusexp(?1/T′),andb(T′)=b0exp(1/T′). Furthermore,the chemical autapse is connected to the neural circuit,and the autapstic currentIaut, which is described by the fast threshold modulation scheme,[30]is defined by

    whereHrepresents the coupling strength of chemical autapse;τis the time lag,which denotes the finite time required for the signal to travel along the axon and return to the neuron itself;VposandVprerefer to the post-synaptic and pre-synaptic membrane potentials, respectively;Vsynis the reversible potential,which the excitatory autapse and inhibitory autapse depends on. IfVsynis greater than the resting potential of a single neuron, the autapse is excitatory, otherwise, it is inhibitory autapse. The parameterθrepresents the synaptic threshold,andσis ratio constant.

    3. Results and discussion

    In this section,the fourth order Runge–Kutta algorithm is adopted to find numerical solution for the functional neuron in time steps of 0.01. The initial values of the two variables in Eq. (3) are selected to be 0.1 and 0.3. The parameter values for the system area=0.8,c=0.1,Vsyn=2,θ=?0.25,σ=10.[18]In order to study the influence of autapse on the action potentials of thermosensitive neurons,it is necessary to ensure that the system is in an oscillatory state. That is,to determine the external forcing current that can cause the system to appear in a limit cycle, the spiking dynamics of the FHN neuron model without autapse connection is calculated, and the results are shown in Fig.1.

    Fig. 1. (a) Time evolution of membrane potential x at Ius =0.5, (b) phase portrait Ius =0.5, and (c) bifurcation curve for the maximum (black solid square)and minimum(red solid square)values of x versus Ius,with parameters selected to be a=0.8,c=0.1,b=0.7,andμ=0.175,and no autapse driving considered in calculations.

    The membrane potential is affected by the external stimuli,and the firing mode can be adjusted for generating periodical oscillation without autapse driving. Obviously,for larger or smaller external forcing currentIus,the system is in a resting state, and only in the range of 0.4

    Confirmed in Fig.2(a)are that the temperature has a great influence on the dynamics of thermosensitive neurons, and that the firing pattern is controlled by temperature completely when other parameters are fixed. The neural activity changes from resting state to periodic oscillation as the temperature increases. When the temperature is less than 5.49, there is a stable solution in this system,and the resting potential is measured with the external forcing currentIus=0.5. That is,neurons are more excitable at moderate temperatures. However,whenT′is greater than 5.49,the amplitudes of membrane potential keeps invariant with the increase of temperature while the ISIs decreases with temperature increasing. The average firing frequency increases with the temperature increasing,and this occurrence becomes distinct when the temperatureT′is lower. After a sharp decrease in ISIs, the curve becomes flat because the sensitivity of firing mode to temperature is weakened. Under high temperature, the amplitude of the firing is reduced, and the number of firings seems to be big, but the duration and height of the firing pattern are very low,and the firing pattern is no longer a spiking pattern. Therefore,only at the optimal temperature can the firing mode carry the neuron information well. The results in Ref.[26]show that the duration of the pulse decreases with temperature increasing. The simulation results are consistent with the experimental results,that is,the average duration of the membrane voltage pulse decreases when the temperature is further increased as shown in Fig.2(b).

    Autapse is a self-synapse,in which there exists a connection between a neuron and itself. With the increase of autaptic time lagτof the autapse, the ISIs of firing patterns increase periodically. When the temperature is considered in the improved FHN model,asτis increased to 62,the firing regularity is destroyed. Surprisingly, whenτis further increased to 75,the spiking behavior once again becomes more regular and dense as indicated in Fig.3.

    Fig. 2. (a) Curve of maximum value (black solid square) and minimum value (red solid circle) of x versus T′, and (b) bifurcation diagram of ISIs varying with temperature T′,with parameters selected to be a=0.8,c=0.1,b=0.7, μ =0.175,and Ius =0.5 in the improved FHN model without autapse driving.

    Fig. 3. (a) Improved FHN model without temperature and (b) improved FHN model with temperature T′=10 versus τ with parameters selected to be with b=0.7,μ =0.175,Ius=0.5,and autaptic intensity H=0.3.

    Furthermore,the autapse connection is activated,and the chemical autaptic current is released to excite the thermosensitive neuron. The changes of ISIs are calculated by adjusting the intensity of autaptic current with constant time delay,then the dependence of time delay in the autapse is presented for possible contrast,and the results are depicted in Fig.4.Technically,the thermosensitive neuron generates spikes under a certain external forcing current, and then it injects a small pulse to postpone or hasten the spiking.

    Indeed, both of intensity and time delay in the autapse have distinct effect on the firing patterns and oscillation mode in the neural activities. The results in Fig.4 demonstrate that forT′=10,asHchanges from 0 to 0.6,the ISIs fluctuate significantly. When no delay in autapse is considered,the autaptic intensity and temperature have the same effect on neuronal discharge,that is,both of them reduce the interspike intervals of membrane potential. At a specific autaptic intensity,the ISI reaches the lowest value and the firing frequency of neurons reaches the highest point as indicated in Fig. 4(a). However,the increase in time lag breaks this occurrence. The ISI of the neuron presents a certain increase and then decreases with autaptic intensity increasing. WhileHis in the range from 0.3 to 0.335,the membrane potential is below zero,and it is classified as a resting state. Whenτis increased to 50 andHis less than 0.07, the firing regularity is destroyed. With the increase of autaptic intensity, the ISI curve changes smoothly.This means that the selection of firing mode is more sensitive to smaller synaptic strength under the longer delay time. Extensive numerical results are presented to identify the firing modes by taming the parameters for the chemical autapse,and the results are shown in Fig.5.

    Fig.4. Bifurcation diagram of ISIs varying with autaptic intensity H under different time lags τ at Ius=0.5,T′=10,and τ =0(a),10(b),50(c),and 100(d).

    Fig.5. Spike trains of improved FHN model with autapse,calculated under Ius=0.5 and T′=10,at(a)τ =0 and H=0.3;(b)τ =10 and H=0.25;(c)τ =10 and H=0.3;(d)τ =50 and H=0.05;(e)τ =50 and H=0.08;(f)τ =100 and H=0.6.

    It is found that the firing patterns of neurons depend on autaptic current,which has different time lags and autaptic intensities. At the same time, in order to observe the influence of temperature on the statistical properties of the membrane potential,the maximum values and minimum values of pulses increase with temperature rising under a certain autaptic current are calculated as shown in Fig.6.

    Forτ=10 andH=0.3,whenT′changes from 0 to 40,the bifurcations are different from those in Fig.2,as shown in Fig.6.The improved FHN model without autapse exhibits one bifurcation point as the temperature changes forIus=0.5. For the improved FHN model with autapse,excitatory autapse can also induce system bifurcation. Interestingly, when the temperature is less than 5.49,the system has a limit cycle withT′changing. At the beginning,there is only a stable equilibrium point in the system, and the membrane potential of neurons converges to a fixed value after time evolution. As the temperature increases to the bifurcation pointT′=1.5,the membrane potential of neurons presents a periodic discharge. WhenT′rises to 2.5,the limit cycle disappears and the system has only one stable state as shown in Figs.6(c1)and 6(c2). In the range of 7 to 11.5, the neurons show small amplitude periodic oscillations, which are illustrated in Figs.6(d1)and 6(d2). Stable periodic oscillations are observed when the temperature is greater than 11.5. The amplitude of membrane potential does not change when the temperature increases to a certain extent.Note that this result is similar to that of the system without autapse in Fig.2. That is to say, excitatory autaptic can change the firing pattern of neurons. At an appropriate temperature,neurons are promoted to produce action potential by excitatory autaptic stimulation. In order to observe the effect of temperature on the statistical properties of membrane potential, the variations of mean duration of spiking with temperature at different autaptic intensities are shown in Fig.7.

    Fig.6. (a)Bifurcation diagrams of xmax and xmin for improved FHN neuronal model versus temperatures,(b1)x–t and(b2)y–x at T′=2,(c1)x–t and(c2)y–x at T′=5,(d1)x–t and(d2)y–x at T′=10,and(e1)x–t and(e2)y–x at T′=20,with other parameters being τ =10,H=0.3,and Ius=0.5.

    Figure 7 shows the variations of average duration of the membrane potential with temperature, where different colors indicate different autaptic intensities. The duration of a spiking can be defined as the time required for the action potential to drop from greater than 0 mV to?0.5 mV, for the differences among thresholds have no qualitative influence on the results. It can be seen from the figure that the simulation results are consistent with the experimental results, that is, the average duration of the membrane potential decreases as the temperature increases.[67]The increase of temperature leads the channel opening time to decrease,which is consistent with the experimental result in the recent literature,[12]that is, the channel opening time is increased by reducing the temperature. The results show that the firing duration of neurons can be affected by the autaptic intensity. The injected autaptic current is positively correlated with the duration of the action potential.However,when the temperature is in a lower range,the autapses can well regulate the firing patterns of neurons. The average duration of pulses is sensitive to autapse connection,so the autapse plays an important role in regulating the neuronal signal processing as described in Ref. [39]. The magnitude of the autaptic current injected into the neuronal system depends not only on the autaptic intensity,but also on the time lag. The mean inter-spike intervalversustemperature is calculated to investigate the effect of time lag on membrane potential.

    Fig.7. Variations of mean duration of spiking with temperatures under different autaptic intensities when τ =30.

    Figure 8 shows the variations mean inter-spike interval of membrane potential with temperatures at different time lags,which are used to elucidate the effect of autapse in the improved FHN model.The mean inter-spike interval of the membrane voltage pulse is positively correlated with temperatures,and the trend of the curve is opposite to that of Fig.7.It is suggested that the increase of temperature promotes the increase of firing frequency of neurons. The firing frequency of neurons can be promoted by increasing the time lag.However,the mean inter-spike interval first decreases and then increases in a certain temperature range atτ=40. To study the regulation mechanism of autapse on membrane potential of thermosensitive neuron, the mean duration of spiking under different autaptic intensities and time lags is calculated in Fig.9.

    Fig.8. Variations of mean inter-spike interval with temperatures for different time lags at autaptic intensity H=0.4.

    At a certain temperature, the mean duration of spiking value is longer,indicating that the discharge frequency of neurons is higher. As can be seen from Fig.9,the time lag starts from 15,and the autaptic intensity and time lag are positively correlated with the frequency of neurons. It is worth noting that for the temperature fixed at 10,the influence of the autaptic intensity on the mean duration of spiking is nonlinear when theτis equal to 1.That is,the mean duration of spiking is sensitive to autapse,but it depends on the temperature. Figure 10 plots the mean durations of spiking varying with autaptic intensity at different temperatures.

    Fig.9. Variation of mean duration of spiking with τ at temperature T′=10 under different autaptic intensities and time lags,with color-scaled autaptic intensity shown on right side.

    Figure 10 shows all curves of mean duration of spiking first rise and then decrease with the increase of autaptic intensity. The results show that the generation of action potential is promoted under an appropriate autaptic intensity.The increase of temperature is conducive to the mean duration of spiking to peak at a smaller autaptic intensityH. And the peak value of the curve mainly depends on the time lag, and the effect of temperature can be ignored. However, temperature can promote the neurons to reach the peak at lowerH. The results show that the autapse regulates the firing of thermosensitive neurons,and the firing of thermosensitive neurons can be promoted by autaptic imtensity and time lag in a certain range.Meanwhile, with the increase of temperature, the system can be changed from a resting state to an oscillation state when the time lag is equal to 5.

    Fig. 10. Variations of mean duration of spiking with autaptic intensity for different time lags at T′=10(a)and 2(b).

    In summary, the involvement of autapse connection can enrich the mode selection and transition in the neural activities, and it indicates that the temperature-induced firing pattern can be balanced and controlled by autaptic current. As is well known, the astrocyte plays an important role in regulating the neural activity,[71–73]therefore,this study can extended by building astrocyte-coupled functional neurons and network,the occurrence of multiple mode and switch between different firing modes can be more attractive.

    4. Conclusions and discussion

    In this paper, an improved thermosensitive FHN neuron model is used to investigate the effect of autapse driving on neural firing activities. Firstly,the bifurcation diagram of isolated FHN neuron with external stimulus is calculated to detect the parameter region for periodic oscillations. By adjusting the external forcing currentIus, the membrane potential can be changed from the resting state to the periodic discharge state, whenIusis increased continuously, and the resting potential of neurons will be restored. In general,the ion channel or membrane is studied under a constant temperature. However, the dynamics of neurons is not only regulated by membrane voltage,but also dependent on membrane temperatures.The effect of temperature on the membrane potential of neurons without autapse is checked. Temperature change affects the rate of biochemical reactions,including the activation and inactivation of membrane ion channels, the activation and release of synapses, and the conduction velocity of action potential. The spontaneous action potentials can be generated in the improved neuron model at an appropriate temperature,and the average duration of the membrane voltage pulse decreases with temperature increasing as indicated in Fig.2.The previous results show that the duration of the pulse decreases with temperature increasing,and it is confirmed in Fig.2,that is,lowering the temperature can increase the channel opening time.

    Autapse is a special kind of synapse,which has the ability to regulate the firing pattern of neurons and participates in the information coding process in the nervous system. The existence of excitatory autapse is confirmed, and its function and characteristics are detected in the recent researches. In addition, the autaptic time delay plays an important role in regulating neuronal firing. Therefore, we investigate the potential mechanism of synaptic changes in firing patterns,especially in thermosensitive neurons. By calculating the mean inter-spike interval and the mean duration of spiking,we find that the electrical activity of thermosensitive neurons can be regulated by autapse,and the firing of thermosensitive neurons can be promoted by autaptic intensities and time lags in a certain domain.With the longer delay time, the choice of discharge mode is more sensitive to the smaller synaptic strength. Temperature can promote the neurons to reach the maximum mean duration of spiking under small autaptic intensities. The results of this study provide a new approach to the potential function of excitatory synapses and the regulation of neuronal firing frequency,and can also arouse the interest in further investigating the effects of time delay and temperature on the dynamics and controlling high-dimensional small-world networks.[74–76]

    猜你喜歡
    馬軍
    Enhance sensitivity to illumination and synchronization in light-dependent neurons?
    Estimation of biophysical properties of cell exposed to electric field
    Interaction of Wave Trains with Defects?
    Dynamics of Spiral Waves Induced by Periodic Mechanical Deformation with Phase Di ff erence?
    Synergy and Redundancy in a Signaling Cascade with Different Feedback Mechanisms?
    Talk about music content and emotion of music movie "The Legend of 1900"
    東方教育(2017年12期)2017-08-23 05:49:54
    宋代兵器鐵連枷淺析
    游戲情感的女大學(xué)生你攤上事了
    前夫中大獎
    故事林(2010年11期)2010-05-14 17:29:36
    用100元讀完大學(xué)
    意林(2006年2期)2006-05-14 14:47:46
    嘟嘟电影网在线观看| 亚洲色图av天堂| 91久久精品电影网| 26uuu在线亚洲综合色| 国产一区二区亚洲精品在线观看| 国产亚洲av嫩草精品影院| 内地一区二区视频在线| 一个人看的www免费观看视频| av在线观看视频网站免费| xxx大片免费视频| 久久97久久精品| 啦啦啦啦在线视频资源| 熟妇人妻久久中文字幕3abv| 亚洲熟女精品中文字幕| 91在线精品国自产拍蜜月| 久久久久性生活片| 免费观看精品视频网站| 国产精品综合久久久久久久免费| 国产男人的电影天堂91| 成人av在线播放网站| 国产精品麻豆人妻色哟哟久久 | 黑人高潮一二区| 亚洲婷婷狠狠爱综合网| 国产在视频线在精品| 国产毛片a区久久久久| 深夜a级毛片| 国产视频首页在线观看| 麻豆乱淫一区二区| 亚洲欧美成人精品一区二区| 2022亚洲国产成人精品| 偷拍熟女少妇极品色| 人妻少妇偷人精品九色| 联通29元200g的流量卡| 国产乱人视频| 欧美性感艳星| 嘟嘟电影网在线观看| 欧美人与善性xxx| 亚洲av国产av综合av卡| 噜噜噜噜噜久久久久久91| 精品一区二区三区视频在线| 久久久久久久久中文| 欧美精品一区二区大全| 色综合站精品国产| 美女高潮的动态| 亚洲精华国产精华液的使用体验| 亚洲成人精品中文字幕电影| 久久精品久久精品一区二区三区| 午夜精品国产一区二区电影 | 人妻制服诱惑在线中文字幕| 亚洲怡红院男人天堂| 一二三四中文在线观看免费高清| 直男gayav资源| 免费大片黄手机在线观看| 欧美日韩在线观看h| or卡值多少钱| 成人二区视频| 国产精品一区二区在线观看99 | 久久精品国产亚洲网站| 麻豆成人av视频| 国产亚洲5aaaaa淫片| 搡老乐熟女国产| 亚洲成人久久爱视频| 一级毛片aaaaaa免费看小| 纵有疾风起免费观看全集完整版 | 免费黄网站久久成人精品| 少妇熟女aⅴ在线视频| 深夜a级毛片| 国产黄片视频在线免费观看| 国产在线一区二区三区精| 三级经典国产精品| 七月丁香在线播放| av女优亚洲男人天堂| 日韩视频在线欧美| 日韩欧美 国产精品| 一边亲一边摸免费视频| 99热6这里只有精品| 中文字幕av在线有码专区| 国内少妇人妻偷人精品xxx网站| 精品久久久久久久久av| 国产69精品久久久久777片| 中文资源天堂在线| 热99在线观看视频| 亚洲av免费高清在线观看| 欧美一级a爱片免费观看看| 日本黄大片高清| 久久久国产一区二区| 亚洲国产色片| 精品久久久久久久人妻蜜臀av| 在线观看av片永久免费下载| 亚洲最大成人av| 99热全是精品| 女人久久www免费人成看片| 国产精品av视频在线免费观看| 天天躁日日操中文字幕| 精品国内亚洲2022精品成人| 91午夜精品亚洲一区二区三区| 日韩强制内射视频| 18禁动态无遮挡网站| 色综合色国产| 日韩三级伦理在线观看| 久久精品夜色国产| 人妻制服诱惑在线中文字幕| 国产欧美另类精品又又久久亚洲欧美| 国产黄色视频一区二区在线观看| 内射极品少妇av片p| 日本色播在线视频| 一区二区三区乱码不卡18| 亚洲av成人精品一区久久| 两个人的视频大全免费| 免费看美女性在线毛片视频| 直男gayav资源| 精品熟女少妇av免费看| 一级毛片电影观看| 国产91av在线免费观看| 1000部很黄的大片| 国产精品精品国产色婷婷| 日本爱情动作片www.在线观看| 国产v大片淫在线免费观看| 三级经典国产精品| 一级a做视频免费观看| 午夜激情欧美在线| 国产白丝娇喘喷水9色精品| 久久久成人免费电影| 亚洲综合精品二区| 青春草视频在线免费观看| 久久久亚洲精品成人影院| 中国国产av一级| 超碰97精品在线观看| 国产黄片美女视频| 精品久久久久久久久av| 午夜福利成人在线免费观看| 国产一级毛片七仙女欲春2| 国产成人福利小说| 亚洲人成网站在线播| 国产熟女欧美一区二区| 国产av不卡久久| 午夜福利在线观看吧| 五月天丁香电影| 成人国产麻豆网| 国产国拍精品亚洲av在线观看| 一级毛片电影观看| 午夜精品在线福利| 亚洲美女搞黄在线观看| 日韩一区二区视频免费看| 国产午夜福利久久久久久| 七月丁香在线播放| 禁无遮挡网站| 91精品国产九色| 看黄色毛片网站| 国产有黄有色有爽视频| 日韩中字成人| 亚洲av一区综合| 亚洲精品成人av观看孕妇| 国产 一区 欧美 日韩| 91狼人影院| 国产亚洲5aaaaa淫片| 最近视频中文字幕2019在线8| 国产精品一区www在线观看| 99久久人妻综合| 一个人看视频在线观看www免费| 亚洲精品自拍成人| 精品一区在线观看国产| 婷婷色综合www| 免费黄网站久久成人精品| 网址你懂的国产日韩在线| 亚洲熟女精品中文字幕| 国产高清国产精品国产三级 | 亚洲国产成人一精品久久久| 看免费成人av毛片| 97人妻精品一区二区三区麻豆| 日韩成人av中文字幕在线观看| 国产中年淑女户外野战色| 亚洲在线自拍视频| 国产精品1区2区在线观看.| 三级国产精品欧美在线观看| 搡女人真爽免费视频火全软件| 国国产精品蜜臀av免费| 久久久久久久大尺度免费视频| 免费av不卡在线播放| 日本猛色少妇xxxxx猛交久久| 成人二区视频| 国产精品综合久久久久久久免费| 亚洲精品影视一区二区三区av| 中文字幕久久专区| 日韩欧美精品v在线| 18禁裸乳无遮挡免费网站照片| a级一级毛片免费在线观看| 少妇人妻一区二区三区视频| 精品人妻熟女av久视频| 人体艺术视频欧美日本| 综合色丁香网| 高清在线视频一区二区三区| 日韩欧美精品v在线| 一本久久精品| 久久鲁丝午夜福利片| 在线免费观看的www视频| a级毛色黄片| 精品不卡国产一区二区三区| 久久99热这里只频精品6学生| 免费黄频网站在线观看国产| 神马国产精品三级电影在线观看| 最后的刺客免费高清国语| 亚洲人成网站在线观看播放| 久久久久久伊人网av| 少妇人妻精品综合一区二区| 亚洲最大成人中文| 国国产精品蜜臀av免费| 十八禁国产超污无遮挡网站| 亚洲精品成人久久久久久| 五月天丁香电影| 天天一区二区日本电影三级| 麻豆国产97在线/欧美| 欧美 日韩 精品 国产| 免费观看av网站的网址| 亚洲aⅴ乱码一区二区在线播放| 免费人成在线观看视频色| av免费观看日本| 久久久色成人| 搞女人的毛片| 男女边吃奶边做爰视频| av线在线观看网站| 精品人妻视频免费看| 春色校园在线视频观看| www.av在线官网国产| 少妇的逼好多水| 中文字幕免费在线视频6| 国产女主播在线喷水免费视频网站 | 能在线免费看毛片的网站| 免费av观看视频| 亚洲av男天堂| 成人亚洲精品av一区二区| 麻豆久久精品国产亚洲av| 嫩草影院新地址| 成年女人在线观看亚洲视频 | 欧美zozozo另类| 亚洲av成人精品一区久久| 精品人妻视频免费看| 精品欧美国产一区二区三| 不卡视频在线观看欧美| 淫秽高清视频在线观看| 黄色欧美视频在线观看| 亚洲av成人精品一二三区| 最近2019中文字幕mv第一页| 一级毛片黄色毛片免费观看视频| 一二三四中文在线观看免费高清| 欧美人与善性xxx| 久久人人爽人人爽人人片va| 国产在线一区二区三区精| 国产精品福利在线免费观看| 狂野欧美白嫩少妇大欣赏| 亚洲经典国产精华液单| 国产黄片视频在线免费观看| 久久亚洲国产成人精品v| 国产欧美另类精品又又久久亚洲欧美| 国产乱人偷精品视频| 日本与韩国留学比较| 老司机影院成人| 国产黄片美女视频| 精华霜和精华液先用哪个| 日本免费a在线| 极品少妇高潮喷水抽搐| 国内揄拍国产精品人妻在线| 美女高潮的动态| 国产女主播在线喷水免费视频网站 | 日韩一区二区视频免费看| 精品一区二区免费观看| 如何舔出高潮| 国产真实伦视频高清在线观看| 国产精品熟女久久久久浪| 免费大片黄手机在线观看| 国产精品日韩av在线免费观看| 又爽又黄a免费视频| av播播在线观看一区| 在现免费观看毛片| 99视频精品全部免费 在线| 嫩草影院新地址| 小蜜桃在线观看免费完整版高清| 国产成人福利小说| 黄色欧美视频在线观看| 黑人高潮一二区| 亚洲美女搞黄在线观看| 国产不卡一卡二| 日韩一区二区三区影片| 亚洲精品自拍成人| 日韩 亚洲 欧美在线| 全区人妻精品视频| 一级毛片我不卡| 免费大片黄手机在线观看| 国产高清国产精品国产三级 | 中文字幕免费在线视频6| 免费高清在线观看视频在线观看| 五月天丁香电影| 欧美日韩综合久久久久久| 天美传媒精品一区二区| 欧美人与善性xxx| 久久久精品94久久精品| 亚洲av中文字字幕乱码综合| 又粗又硬又长又爽又黄的视频| 直男gayav资源| 97人妻精品一区二区三区麻豆| 亚洲精品第二区| 夫妻性生交免费视频一级片| 色哟哟·www| 成年免费大片在线观看| 成人亚洲欧美一区二区av| 色哟哟·www| 国产精品久久久久久久久免| 国产黄色免费在线视频| 亚洲精品日本国产第一区| 国产男女超爽视频在线观看| 午夜福利视频精品| 高清视频免费观看一区二区 | 少妇熟女aⅴ在线视频| 噜噜噜噜噜久久久久久91| 久久精品熟女亚洲av麻豆精品 | 亚洲国产成人一精品久久久| 亚洲欧美日韩无卡精品| 男人狂女人下面高潮的视频| 亚洲欧美精品专区久久| 国产视频内射| 亚洲精品乱码久久久久久按摩| 一本一本综合久久| 日本黄大片高清| 性色avwww在线观看| 久久久久久久久久久免费av| 卡戴珊不雅视频在线播放| 伦精品一区二区三区| 久久久久久久午夜电影| 午夜免费观看性视频| 亚洲一级一片aⅴ在线观看| 久久精品国产亚洲av天美| 国产 一区精品| 99热全是精品| 国产黄频视频在线观看| 国产亚洲一区二区精品| av播播在线观看一区| 亚洲成人久久爱视频| 人妻夜夜爽99麻豆av| 久久国内精品自在自线图片| 日本免费在线观看一区| 欧美成人一区二区免费高清观看| 亚洲av二区三区四区| 两个人视频免费观看高清| 伦精品一区二区三区| 深爱激情五月婷婷| 一个人看视频在线观看www免费| 亚洲最大成人av| 赤兔流量卡办理| 一级a做视频免费观看| 免费观看精品视频网站| 男女边吃奶边做爰视频| 免费看不卡的av| 色哟哟·www| 久久精品熟女亚洲av麻豆精品 | 色尼玛亚洲综合影院| 国内揄拍国产精品人妻在线| 久久精品国产鲁丝片午夜精品| av国产免费在线观看| 干丝袜人妻中文字幕| 亚洲乱码一区二区免费版| 亚洲精品成人av观看孕妇| 亚洲精品自拍成人| 国产亚洲一区二区精品| 久久国产乱子免费精品| 欧美极品一区二区三区四区| 亚洲国产av新网站| 又爽又黄a免费视频| 99热网站在线观看| 国产色爽女视频免费观看| 免费电影在线观看免费观看| 国产高清三级在线| 国产成人精品婷婷| 日韩电影二区| 日韩强制内射视频| 久久久久久久久久成人| 国精品久久久久久国模美| www.av在线官网国产| 国精品久久久久久国模美| 免费大片黄手机在线观看| 日日摸夜夜添夜夜爱| 日韩国内少妇激情av| 91在线精品国自产拍蜜月| 久久鲁丝午夜福利片| 成人午夜高清在线视频| 国产白丝娇喘喷水9色精品| 天天躁日日操中文字幕| 你懂的网址亚洲精品在线观看| 婷婷色综合www| 亚洲电影在线观看av| 久久久色成人| 日韩av在线免费看完整版不卡| 久久精品夜色国产| 亚洲欧美精品专区久久| 欧美极品一区二区三区四区| 免费av毛片视频| 中文字幕人妻熟人妻熟丝袜美| 国产精品久久久久久精品电影| 中文字幕免费在线视频6| 久久这里只有精品中国| 亚洲天堂国产精品一区在线| 97超视频在线观看视频| 美女被艹到高潮喷水动态| 欧美另类一区| 国产午夜精品论理片| 亚洲av一区综合| 看免费成人av毛片| 午夜老司机福利剧场| 一级毛片黄色毛片免费观看视频| 成人av在线播放网站| 亚洲精品自拍成人| 一级av片app| 黄片wwwwww| 亚洲精品乱码久久久v下载方式| 亚洲av成人精品一二三区| 高清在线视频一区二区三区| 国产亚洲91精品色在线| 欧美高清成人免费视频www| 成人漫画全彩无遮挡| 高清视频免费观看一区二区 | 亚洲欧美精品自产自拍| 最近2019中文字幕mv第一页| 深夜a级毛片| 免费黄网站久久成人精品| 日日撸夜夜添| 成人欧美大片| 青春草亚洲视频在线观看| 尾随美女入室| 一个人观看的视频www高清免费观看| 久久久久久久久久久免费av| 亚洲最大成人手机在线| 亚洲精品乱码久久久久久按摩| 色视频www国产| 少妇被粗大猛烈的视频| 午夜久久久久精精品| 国产亚洲91精品色在线| 欧美日本视频| 在线观看美女被高潮喷水网站| 亚洲熟女精品中文字幕| 直男gayav资源| 日韩大片免费观看网站| 成人欧美大片| 欧美日韩视频高清一区二区三区二| 国产伦在线观看视频一区| 乱人视频在线观看| 成人一区二区视频在线观看| 亚洲美女视频黄频| 亚洲精品日本国产第一区| 三级毛片av免费| 大香蕉久久网| 亚洲欧美日韩卡通动漫| kizo精华| 91久久精品国产一区二区三区| 亚洲在线自拍视频| 黑人高潮一二区| 国产日韩欧美在线精品| 亚洲自偷自拍三级| 国产色爽女视频免费观看| 99热网站在线观看| 别揉我奶头 嗯啊视频| 亚洲国产av新网站| 别揉我奶头 嗯啊视频| 一级爰片在线观看| 22中文网久久字幕| 国产老妇伦熟女老妇高清| 国产免费福利视频在线观看| 久久久久九九精品影院| 三级男女做爰猛烈吃奶摸视频| 女人十人毛片免费观看3o分钟| 国产伦一二天堂av在线观看| 国产高清国产精品国产三级 | 一级a做视频免费观看| 99热这里只有是精品50| 日韩欧美三级三区| 国产 一区 欧美 日韩| 亚洲国产av新网站| 亚洲精品国产av蜜桃| 神马国产精品三级电影在线观看| 久久久久九九精品影院| 国产精品一区二区在线观看99 | 女的被弄到高潮叫床怎么办| 蜜臀久久99精品久久宅男| 欧美xxxx性猛交bbbb| 日韩欧美 国产精品| 高清欧美精品videossex| 大陆偷拍与自拍| 亚洲精品影视一区二区三区av| 少妇熟女aⅴ在线视频| 亚洲精品久久午夜乱码| av在线亚洲专区| 最近视频中文字幕2019在线8| 波多野结衣巨乳人妻| 色哟哟·www| 啦啦啦韩国在线观看视频| 777米奇影视久久| videos熟女内射| 婷婷六月久久综合丁香| 亚洲不卡免费看| 3wmmmm亚洲av在线观看| 伊人久久国产一区二区| av一本久久久久| 白带黄色成豆腐渣| 麻豆成人午夜福利视频| 五月伊人婷婷丁香| 日韩视频在线欧美| 最近中文字幕高清免费大全6| 你懂的网址亚洲精品在线观看| 免费黄色在线免费观看| 国产伦精品一区二区三区视频9| 成人一区二区视频在线观看| 91在线精品国自产拍蜜月| 日本-黄色视频高清免费观看| 麻豆乱淫一区二区| 亚洲美女视频黄频| 波多野结衣巨乳人妻| 少妇猛男粗大的猛烈进出视频 | 国产精品一区二区三区四区久久| 欧美人与善性xxx| 婷婷色综合www| 久久99精品国语久久久| 精品亚洲乱码少妇综合久久| 欧美另类一区| 国产精品1区2区在线观看.| 国产成人aa在线观看| 久久久久精品久久久久真实原创| 国产欧美日韩精品一区二区| 国产高清有码在线观看视频| 成人毛片60女人毛片免费| 欧美丝袜亚洲另类| 亚洲av.av天堂| 欧美高清成人免费视频www| 久久午夜福利片| 日韩av在线免费看完整版不卡| 免费黄网站久久成人精品| 亚洲欧洲日产国产| 网址你懂的国产日韩在线| 精品人妻熟女av久视频| 免费播放大片免费观看视频在线观看| 99久久精品一区二区三区| 午夜福利视频精品| 亚洲精品亚洲一区二区| 狠狠精品人妻久久久久久综合| 26uuu在线亚洲综合色| 国产久久久一区二区三区| 看免费成人av毛片| 亚洲美女视频黄频| 又爽又黄a免费视频| 亚洲伊人久久精品综合| 国产精品麻豆人妻色哟哟久久 | 亚洲国产色片| 男人舔奶头视频| 亚洲人与动物交配视频| 久久精品人妻少妇| 久久久久精品性色| 国产精品久久久久久久电影| 大片免费播放器 马上看| 亚洲经典国产精华液单| 精品久久久久久久末码| 免费av不卡在线播放| 性色avwww在线观看| 日本黄大片高清| 国产精品美女特级片免费视频播放器| 亚洲av中文av极速乱| 久久精品久久久久久久性| 亚洲成人精品中文字幕电影| 女的被弄到高潮叫床怎么办| 日韩不卡一区二区三区视频在线| 日韩欧美国产在线观看| 国产精品人妻久久久影院| 国产伦精品一区二区三区四那| 嫩草影院精品99| 亚洲最大成人中文| 好男人视频免费观看在线| 成年女人看的毛片在线观看| 久久久久精品性色| 1000部很黄的大片| 国产麻豆成人av免费视频| 久久久亚洲精品成人影院| 国产亚洲精品久久久com| 日韩av在线免费看完整版不卡| 又爽又黄a免费视频| 嫩草影院精品99| 欧美三级亚洲精品| 久热久热在线精品观看| 男女边吃奶边做爰视频| 成人亚洲欧美一区二区av| 欧美3d第一页| 少妇丰满av| 国产午夜精品一二区理论片| 精品久久久久久久末码| 91aial.com中文字幕在线观看| 精品久久久噜噜| 91精品伊人久久大香线蕉| 亚洲av国产av综合av卡| 国产一区有黄有色的免费视频 | 欧美变态另类bdsm刘玥| 亚洲va在线va天堂va国产| 美女大奶头视频| 天堂av国产一区二区熟女人妻| 一级毛片我不卡| 亚洲国产精品sss在线观看| 国产欧美日韩精品一区二区| 丰满少妇做爰视频| av免费观看日本| 赤兔流量卡办理| 99久久精品国产国产毛片| 自拍偷自拍亚洲精品老妇| 最近最新中文字幕大全电影3| 日本av手机在线免费观看| 天天躁夜夜躁狠狠久久av| 中文在线观看免费www的网站| 久久精品久久精品一区二区三区| 亚洲精品乱码久久久久久按摩| 亚洲人成网站高清观看| 一个人观看的视频www高清免费观看| 只有这里有精品99|