The Hodgkin–Huxley model assumes independent ion channel activation,although mutual interactions are common in biological systems.This raises the problem why neurons would favor independent over cooperative channel a...The Hodgkin–Huxley model assumes independent ion channel activation,although mutual interactions are common in biological systems.This raises the problem why neurons would favor independent over cooperative channel activation.In this study,we evaluate how cooperative activation of sodium channels affects the neuron’s information processing and energy consumption.Simulations of the stochastic Hodgkin–Huxley model with cooperative activation of sodium channels show that,while cooperative activation enhances neuronal information processing capacity,it greatly increases the neuron’s energy consumption.As a result,cooperative activation of sodium channel degrades the energy efficiency for neuronal information processing.This discovery improves our understanding of the design principles for neural systems,and may provide insights into future designs of the neuromorphic computing devices as well as systematic understanding of pathological mechanisms for neural diseases.展开更多
Changes in the concentration of charged ions in neurons can generate induced electric fields,which can further modulate cell membrane potential.In this paper,Fourier coefficients are used to investigate the effect of ...Changes in the concentration of charged ions in neurons can generate induced electric fields,which can further modulate cell membrane potential.In this paper,Fourier coefficients are used to investigate the effect of electric field on vibrational resonance for signal detection in a single neuron model and a bidirectionally coupled neuron model,respectively.The study found that the internal electric field weakens vibrational resonance by changing two factors,membrane potential and phase-locked mode,while the periodic external electric field of an appropriate frequency significantly enhances the vibrational resonance,suggesting that the external electric field may play a constructive role in the detection of weak signals in the brain and neuronal systems.Furthermore,when the coupling of two neurons is considered,the effect of the electric field on the vibrational resonance is similar to that of a single neuron.The paper also illustrates the effect of electric field coupling on vibrational resonance.This study may provide a new theoretical basis for understanding information encoding and transmission in neurons.展开更多
The phenomenon of activity synchronization in biological neural network is considered. Simulation of neurons dynamics in the 6-layer neural network with 110 elements in different regimes： regular spikes, chaotic spik...The phenomenon of activity synchronization in biological neural network is considered. Simulation of neurons dynamics in the 6-layer neural network with 110 elements in different regimes： regular spikes, chaotic spikes, regular and chaotic bursting, etc was performed. Izhykevich＇s phenomenological model that displays different types of activity inherent for real biological neurons was used for simulation. Space-time diagram for the entire network and raster plots for the whole structure and for each layer separately were built for visual inspection of neural network activity synchronization. Synchronization coefficients based on cross-correlation times of action potentials for all neurons pairs were calculated for the whole neural system and for each layer separately.展开更多
Objective The present study aimed to investigate the electrophysiological properties of wide dynamic range （WDR） neurons in spinal dorsal horn of rats with neuropathic pain induced by lumber 5 （L5） spinal nerve li...Objective The present study aimed to investigate the electrophysiological properties of wide dynamic range （WDR） neurons in spinal dorsal horn of rats with neuropathic pain induced by lumber 5 （L5） spinal nerve ligation （SNL） in a large size of samples.Methods Adult Sprague-Dawley rats were divided into normal and SNL groups.Electrophysiological technique was used to record the characteristics of WDR neurons in the spinal dorsal horn.Results Compared with the WDR neurons in normal rats,the WDR neurons in SNL rats showed an increase in excitability,manifested by an enlargement of the receptive field size,an increase in the proportion of neurons that exhibited spontaneous activities,decreases in the Cresponse threshold and latency,and an increase in the C-response duration.In addition,the numbers of A-and C-fiberevoked discharges were smaller in SNL rats than in normal rats.Conclusion The excitability of spinal WDR neurons increased in rats with neuropathic pain induced by L5 SNL.The increase in excitability of WDR neurons may contribute to the development of neuropathic pain.展开更多
Many animals can detect the multi-frequency signals from their external surroundings.The understanding for underlying mechanism of signal detection can apply the theory of vibrational resonance,in which the moderate h...Many animals can detect the multi-frequency signals from their external surroundings.The understanding for underlying mechanism of signal detection can apply the theory of vibrational resonance,in which the moderate high frequency driving can maximize the nonlinear system's response to the low frequency subthreshold signal.In this work,we study the roles of chemical autapse on the vibrational resonance in a single neuron for signal detection.We reveal that the vibrational resonance is strengthened significantly by the inhibitory autapse in the neuron,while it is weakened typically by the excitatory autapse.It is generally believed that the inhibitory synapse has a suppressive effect in neuronal dynamics.However,we find that the detection of the neuron to the low frequency subthreshold signal can be improved greatly by the inhibitory autapse.Our finding indicates that the inhibitory synapse may act constructively on the detection of weak signal in the brain and neuronal system.展开更多
Objective To analyse the antinociceptive effect of red nucleus (RN) and its role in the antinociceptive effect of muscle spindle afferents. Methods The single units of RN or wide dynamic range (WDR) neuron in the sp...Objective To analyse the antinociceptive effect of red nucleus (RN) and its role in the antinociceptive effect of muscle spindle afferents. Methods The single units of RN or wide dynamic range (WDR) neuron in the spinal cord dorsal horn were extracelluarly recorded. The effects of RN stimulation on nociceptive responses (C fibers evoked responses, C responses) of WDR neurons were observed. The influence of muscle spindle afferents elicited by intravenous administration of succinylcholine (Sch) on the spontaneous discharge of RN neurons and on C responses of WDR neurons were observed. The effect of muscle spindle afferents on C responses of WDR neurons after unilateral lesions of RN was also observed. Results Electrical stimulation of the RN produced a significantly inhibitory effect on the nociceptive responses of WDR neurons. RN neurons were excited by muscle spindle afferents. Muscle spindle afferents significantly inhibited C response of WDR neurons and this inhibitory effect was reduced by lesions of RN. Conclusion RN neurons have a significant antinociceptive effect and might be involved in the antinociceptive effects elicited by muscle spindle afferents.展开更多
Objective: To study the effects of clinical concentration of sevoflurane on activity of wide dynamic range neurons. Methods: Eight Spraque-Dawley rats(male) were selected. Their spinal cords were exposed and transecte...Objective: To study the effects of clinical concentration of sevoflurane on activity of wide dynamic range neurons. Methods: Eight Spraque-Dawley rats(male) were selected. Their spinal cords were exposed and transected at T 9-10 level. The rate of firings of single neurons in the dorsal horn in response to electrical stimulation of skin was recorded with microelectrodes. The early and late discharges were observed when rats inhaled 0.5%, 1.0%, 1.5%, and 2.0% sevoflurane. Results: Sevoflurane suppressed the early and late discharges at the concentration of 0.5%, 1.0%, 1.5%, and 2.0%. Compared with early discharges, the extent of inhibition of late discharges was wider at the concentration of 1%, 1.5%, and 2.0% of sevoflurane. Conclusion: It is indicated that sevoflurane could suppress the transmission of nociceptive and non-nociceptive stimulation at dorsal horn. The suppression on nociceptive imput is stronger than that on non-nociceptive imput when the concentration of sevoflurane is more than 1%.展开更多
Spiral waves have been observed in the biological experiments on rat cortex perfused with drugs which can block inhibitory synapse and switch neuron excitability from type II to type I. To simulate the spiral waves ob...Spiral waves have been observed in the biological experiments on rat cortex perfused with drugs which can block inhibitory synapse and switch neuron excitability from type II to type I. To simulate the spiral waves observed in the experiment, the spatiotemporal patterns are investigated in a network composed of neurons with type I and II excitabilities and excitatory coupling. Spiral waves emerge when the percentage(p) of neurons with type I excitability in the network is at middle levels, which is dependent on the coupling strength. Compared with other spatial patterns which appear at different p values, spiral waves exhibit optimal spatial correlation at a certain spatial frequency, implying the occurrence of spatial coherence resonance-like phenomenon. Some dynamical characteristics of the network such as mean firing frequency and synchronous degree can be well interpreted with distinct properties between type I excitability and type II excitability. The results not only identify dynamics of spiral waves in neuronal networks composed of neurons with different excitabilities, but also are helpful to understanding the emergence of spiral waves observed in the biological experiment.展开更多
Background Alzheimer’s disease(AD)is a progressive multifaceted neurodegenerative disorder for which no disease-modifying treatment exists.Neuroinflammation is central to the pathology progression,with evidence sugge...Background Alzheimer’s disease(AD)is a progressive multifaceted neurodegenerative disorder for which no disease-modifying treatment exists.Neuroinflammation is central to the pathology progression,with evidence suggesting that microglia-released galectin-3(gal3)plays a pivotal role by amplifying neuroinflammation in AD.However,the possible involvement of gal3 in the disruption of neuronal network oscillations typical of AD remains unknown.Methods Here,we investigated the functional implications of gal3 signaling on experimentally induced gamma oscillations ex vivo(20-80 Hz)by performing electrophysiological recordings in the hippocampal CA3 area of wild-type(WT)mice and of the 5×FAD mouse model of AD.In addition,the recorded slices from WT mice under acute gal3 application were analyzed with RT-qPCR to detect expression of some neuroinflammation-related genes,and amyloid-β(Aβ)plaque load was quantified by immunostaining in the CA3 area of 6-month-old 5×FAD mice with or without Gal3 knockout(KO).Results Gal3 application decreased gamma oscillation power and rhythmicity in an activity-dependent manner,which was accompanied by impairment of cellular dynamics in fast-spiking interneurons(FSNs)and pyramidal cells.We found that the gal3-induced disruption was mediated by the gal3 carbohydrate-recognition domain and prevented by the gal3 inhibitor TD139,which also prevented Aβ42-induced degradation of gamma oscillations.Further-more,the 5×FAD mice lacking gal3(5×FAD-Gal3KO)exhibited WT-like gamma network dynamics and decreased Aβplaque load.Conclusions We report for the first time that gal3 impairs neuronal network dynamics by spike-phase uncoupling of FSNs,inducing a network performance collapse.Moreover,our findings suggest gal3 inhibition as a potential therapeutic strategy to counteract the neuronal network instability typical of AD and other neurological disorders encompassing neuroinflammation and cognitive decline.展开更多
Clinical medicine and experiments have shown that electrophysiological activities on neuronal disease systems such as the epilepsy and Parkinson can exhibit the evolutions of complex dynamical behaviors and their tran...Clinical medicine and experiments have shown that electrophysiological activities on neuronal disease systems such as the epilepsy and Parkinson can exhibit the evolutions of complex dynamical behaviors and their transitions, which are closely related to the generation mechanism of neuronal diseases. Traditionally, electrophysiological activities have been analyzed from the statistical methods. Although some ideal results have been obtained, mechanisms of complex electrophysiological activities in neuronal systems cannot yet be disclosed. Dynamics modelling can help researchers to explore the mechanisms of electro- physiological activities of neuronal disease systems. By constructing reasonable physiological dynamical model, inner relation between the dynamics model and representation behaviors of the neuronal disease systems can be further studied. In addition, based on the constructed network model, we can also explore mechanisms of the evolutions of dynamical behaviors and their transitions of the initiation, propagation and termination of different kinds of the seizures. Finally, we can design the feasible control method to regulate dynamics behaviors of the seizures so as to realize the healthy neuronal firings.展开更多
基金supported by the Fundamental Research Funds for the Central Universities(Grant No.lzujbky-2021-62)the Shanghai Municipal Science and Technology Major Project(Grant No.2018SHZDZX01)Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence(LCNBI)and ZJLab,and the National Natural Science Foundation of China(Grant No.12247101).
文摘The Hodgkin–Huxley model assumes independent ion channel activation,although mutual interactions are common in biological systems.This raises the problem why neurons would favor independent over cooperative channel activation.In this study,we evaluate how cooperative activation of sodium channels affects the neuron’s information processing and energy consumption.Simulations of the stochastic Hodgkin–Huxley model with cooperative activation of sodium channels show that,while cooperative activation enhances neuronal information processing capacity,it greatly increases the neuron’s energy consumption.As a result,cooperative activation of sodium channel degrades the energy efficiency for neuronal information processing.This discovery improves our understanding of the design principles for neural systems,and may provide insights into future designs of the neuromorphic computing devices as well as systematic understanding of pathological mechanisms for neural diseases.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51737003 and 51977060)the Natural Science Foundation of Hebei Province,China(Grant No.E2011202051)。
文摘Changes in the concentration of charged ions in neurons can generate induced electric fields,which can further modulate cell membrane potential.In this paper,Fourier coefficients are used to investigate the effect of electric field on vibrational resonance for signal detection in a single neuron model and a bidirectionally coupled neuron model,respectively.The study found that the internal electric field weakens vibrational resonance by changing two factors,membrane potential and phase-locked mode,while the periodic external electric field of an appropriate frequency significantly enhances the vibrational resonance,suggesting that the external electric field may play a constructive role in the detection of weak signals in the brain and neuronal systems.Furthermore,when the coupling of two neurons is considered,the effect of the electric field on the vibrational resonance is similar to that of a single neuron.The paper also illustrates the effect of electric field coupling on vibrational resonance.This study may provide a new theoretical basis for understanding information encoding and transmission in neurons.
文摘The phenomenon of activity synchronization in biological neural network is considered. Simulation of neurons dynamics in the 6-layer neural network with 110 elements in different regimes： regular spikes, chaotic spikes, regular and chaotic bursting, etc was performed. Izhykevich＇s phenomenological model that displays different types of activity inherent for real biological neurons was used for simulation. Space-time diagram for the entire network and raster plots for the whole structure and for each layer separately were built for visual inspection of neural network activity synchronization. Synchronization coefficients based on cross-correlation times of action potentials for all neurons pairs were calculated for the whole neural system and for each layer separately.
基金supported by the grants from National Natural Science Foundation of China(No. 30600173,81070893)the Key Project of China Ministry of Education(No. 109003)+1 种基金the National Basic Research Development Program(973 Program) of China (No.2007CB512501)Beijing Municipal Commission of Education "Special Grants for Outstanding Ph.D Program Tutors"
文摘Objective The present study aimed to investigate the electrophysiological properties of wide dynamic range （WDR） neurons in spinal dorsal horn of rats with neuropathic pain induced by lumber 5 （L5） spinal nerve ligation （SNL） in a large size of samples.Methods Adult Sprague-Dawley rats were divided into normal and SNL groups.Electrophysiological technique was used to record the characteristics of WDR neurons in the spinal dorsal horn.Results Compared with the WDR neurons in normal rats,the WDR neurons in SNL rats showed an increase in excitability,manifested by an enlargement of the receptive field size,an increase in the proportion of neurons that exhibited spontaneous activities,decreases in the Cresponse threshold and latency,and an increase in the C-response duration.In addition,the numbers of A-and C-fiberevoked discharges were smaller in SNL rats than in normal rats.Conclusion The excitability of spinal WDR neurons increased in rats with neuropathic pain induced by L5 SNL.The increase in excitability of WDR neurons may contribute to the development of neuropathic pain.
基金Project supported partially by the National Natural Science Foundation of China(Grant Nos.11675112,11705116,11675134,and 11874310)the National Natural Science Foundation of China for the 111 Project(Grant No.B16029).
文摘Many animals can detect the multi-frequency signals from their external surroundings.The understanding for underlying mechanism of signal detection can apply the theory of vibrational resonance,in which the moderate high frequency driving can maximize the nonlinear system's response to the low frequency subthreshold signal.In this work,we study the roles of chemical autapse on the vibrational resonance in a single neuron for signal detection.We reveal that the vibrational resonance is strengthened significantly by the inhibitory autapse in the neuron,while it is weakened typically by the excitatory autapse.It is generally believed that the inhibitory synapse has a suppressive effect in neuronal dynamics.However,we find that the detection of the neuron to the low frequency subthreshold signal can be improved greatly by the inhibitory autapse.Our finding indicates that the inhibitory synapse may act constructively on the detection of weak signal in the brain and neuronal system.
基金ThisresearchwassupportedbytheNationalNaturalScienceFoundationofChina (No .3 90 70 3 3 4)
文摘Objective To analyse the antinociceptive effect of red nucleus (RN) and its role in the antinociceptive effect of muscle spindle afferents. Methods The single units of RN or wide dynamic range (WDR) neuron in the spinal cord dorsal horn were extracelluarly recorded. The effects of RN stimulation on nociceptive responses (C fibers evoked responses, C responses) of WDR neurons were observed. The influence of muscle spindle afferents elicited by intravenous administration of succinylcholine (Sch) on the spontaneous discharge of RN neurons and on C responses of WDR neurons were observed. The effect of muscle spindle afferents on C responses of WDR neurons after unilateral lesions of RN was also observed. Results Electrical stimulation of the RN produced a significantly inhibitory effect on the nociceptive responses of WDR neurons. RN neurons were excited by muscle spindle afferents. Muscle spindle afferents significantly inhibited C response of WDR neurons and this inhibitory effect was reduced by lesions of RN. Conclusion RN neurons have a significant antinociceptive effect and might be involved in the antinociceptive effects elicited by muscle spindle afferents.
文摘Objective: To study the effects of clinical concentration of sevoflurane on activity of wide dynamic range neurons. Methods: Eight Spraque-Dawley rats(male) were selected. Their spinal cords were exposed and transected at T 9-10 level. The rate of firings of single neurons in the dorsal horn in response to electrical stimulation of skin was recorded with microelectrodes. The early and late discharges were observed when rats inhaled 0.5%, 1.0%, 1.5%, and 2.0% sevoflurane. Results: Sevoflurane suppressed the early and late discharges at the concentration of 0.5%, 1.0%, 1.5%, and 2.0%. Compared with early discharges, the extent of inhibition of late discharges was wider at the concentration of 1%, 1.5%, and 2.0% of sevoflurane. Conclusion: It is indicated that sevoflurane could suppress the transmission of nociceptive and non-nociceptive stimulation at dorsal horn. The suppression on nociceptive imput is stronger than that on non-nociceptive imput when the concentration of sevoflurane is more than 1%.
基金supported by the National Natural Science Foundation of China(Grant Nos.11372224&11572225)
文摘Spiral waves have been observed in the biological experiments on rat cortex perfused with drugs which can block inhibitory synapse and switch neuron excitability from type II to type I. To simulate the spiral waves observed in the experiment, the spatiotemporal patterns are investigated in a network composed of neurons with type I and II excitabilities and excitatory coupling. Spiral waves emerge when the percentage(p) of neurons with type I excitability in the network is at middle levels, which is dependent on the coupling strength. Compared with other spatial patterns which appear at different p values, spiral waves exhibit optimal spatial correlation at a certain spatial frequency, implying the occurrence of spatial coherence resonance-like phenomenon. Some dynamical characteristics of the network such as mean firing frequency and synchronous degree can be well interpreted with distinct properties between type I excitability and type II excitability. The results not only identify dynamics of spiral waves in neuronal networks composed of neurons with different excitabilities, but also are helpful to understanding the emergence of spiral waves observed in the biological experiment.
基金funding provided by Karolinska Institute.This work was supported by the Swedish Research Council,the Swedish Brain Foundation,the Swedish Alzheimer Foundation,theÅhlén Foundation(AF),the Berger Foundation(TD),the Olle Engkvist Foundation(TD),G&K Kock Foundation(TD),the Strategic Research Area MultiPark at Lund University(TD),the Foundation for Geriatric Diseases at Karolinska Institutet,theÅhlén Foundation(YAT),Consejo Nacional de Ciencia y Tecnología(CONACYT)postdoctoral fellowships and StratNeuro program at Karolinska Institutet(LEAG),Lindhés Advokabyra AB Grant and Stohnes Stiftelse(LEAG,YAT)the Spanish Ministerio de Ciencia e Innovación(MICIN/AEI/FEDER:PID2019-107677 GB-I00,ARM).
文摘Background Alzheimer’s disease(AD)is a progressive multifaceted neurodegenerative disorder for which no disease-modifying treatment exists.Neuroinflammation is central to the pathology progression,with evidence suggesting that microglia-released galectin-3(gal3)plays a pivotal role by amplifying neuroinflammation in AD.However,the possible involvement of gal3 in the disruption of neuronal network oscillations typical of AD remains unknown.Methods Here,we investigated the functional implications of gal3 signaling on experimentally induced gamma oscillations ex vivo(20-80 Hz)by performing electrophysiological recordings in the hippocampal CA3 area of wild-type(WT)mice and of the 5×FAD mouse model of AD.In addition,the recorded slices from WT mice under acute gal3 application were analyzed with RT-qPCR to detect expression of some neuroinflammation-related genes,and amyloid-β(Aβ)plaque load was quantified by immunostaining in the CA3 area of 6-month-old 5×FAD mice with or without Gal3 knockout(KO).Results Gal3 application decreased gamma oscillation power and rhythmicity in an activity-dependent manner,which was accompanied by impairment of cellular dynamics in fast-spiking interneurons(FSNs)and pyramidal cells.We found that the gal3-induced disruption was mediated by the gal3 carbohydrate-recognition domain and prevented by the gal3 inhibitor TD139,which also prevented Aβ42-induced degradation of gamma oscillations.Further-more,the 5×FAD mice lacking gal3(5×FAD-Gal3KO)exhibited WT-like gamma network dynamics and decreased Aβplaque load.Conclusions We report for the first time that gal3 impairs neuronal network dynamics by spike-phase uncoupling of FSNs,inducing a network performance collapse.Moreover,our findings suggest gal3 inhibition as a potential therapeutic strategy to counteract the neuronal network instability typical of AD and other neurological disorders encompassing neuroinflammation and cognitive decline.
文摘Clinical medicine and experiments have shown that electrophysiological activities on neuronal disease systems such as the epilepsy and Parkinson can exhibit the evolutions of complex dynamical behaviors and their transitions, which are closely related to the generation mechanism of neuronal diseases. Traditionally, electrophysiological activities have been analyzed from the statistical methods. Although some ideal results have been obtained, mechanisms of complex electrophysiological activities in neuronal systems cannot yet be disclosed. Dynamics modelling can help researchers to explore the mechanisms of electro- physiological activities of neuronal disease systems. By constructing reasonable physiological dynamical model, inner relation between the dynamics model and representation behaviors of the neuronal disease systems can be further studied. In addition, based on the constructed network model, we can also explore mechanisms of the evolutions of dynamical behaviors and their transitions of the initiation, propagation and termination of different kinds of the seizures. Finally, we can design the feasible control method to regulate dynamics behaviors of the seizures so as to realize the healthy neuronal firings.
