Search

•A neuron membrane with two capacitive variables is presented.•Light-sensitive ion channel is designed to enhance light sensitivity property of functional membrane.•Energy function is defined to discern its dependence on firing modes.•An adaptive law controls the growth of capacitive parameters under energy flow.

Autapse connected to the neuron can change the electric activity of neuron. The effect of autapse on neuronal activity is often described by adding an additive forcing current along a close loop, which is described by a time-delayed feedback on the membrane potential. Neuron often responds to electric autapse forcing sensitively and quickly, while the chemical autapse changes the electric activity of neuron slowly. By applying external forcing, a shift transition of electric activity can be more easily induced by the electric autapse than the chemical autapse. Our results confirm that chemical autapse can enhance and/or suppress the transition of electric activity with excitable or inhibitory type driven by electric autapse, vice versa. It indicates that an appropriate switch-off-on for autapse can make the neuron give different types of response to external forcing. Particularly, cooperation and competition between chemical and electric autapse help neuron response to external forcing in the most reliable way.

Autapse is a type of synapse that connects axon and dendrites of the same neuron, and the effect is often detected by close-loop feedback in axonal action potentials to the owned dendritic tree. An artificial autapse was introduced into the Hindmarsh-Rose neuron model, and a regular network was designed to detect the regular pattern formation induced by autapse. It was found that target wave emerged in the network even when only a single autapse was considered. By increasing the (autapse density) number of neurons with autapse, for example, a regular area (2×2, 3×3, 4×4, 5×5 neurons) under autapse induced target wave by selecting the feedback gain and time-delay in autapse. Spiral waves were also observed under optimized feedback gain and time delay in autapses because of coherence-like resonance in the network induced by some electric autapses connected to some neurons. This confirmed that the electric autapse has a critical role in exciting and regulating the collective behaviors of neurons by generating stable regular waves (target waves, spiral waves) in the network. The wave length of the induced travelling wave (target wave, spiral wave), because of local effect of autapse, was also calculated to understand the waveprofile in the network of neurons.

The effect of autapse on adjusting the membrane of potentials of neuron is described by imposing a time-delayed feedback on the membrane of neuron in a close loop type, and the Hindmarsh-Rose (HR) neuron under autapse is investigated. Firstly, the electric activity of single HR neuron under electric autapse and chemical autapse is investigated. It is found that quiescent neuron is activated due to appropriate time delay and feedback gain in the autapse, and the autapse plays an important role in waking up neuron. The parameter region for periodic, chaotic activity of neuron under autapse is calculated in a numerical way, and transition from spiking to bursting is observed by increasing the feedback gain and time delay carefully. Furthermore, the collective electric activities of neurons in a ring network is investigated and abundant electric activities are observed due to the competition between the autapse and the time-delayed coupling between adjacent neurons in the network, and time delay in coupling between neurons also plays an important role in enhancing synchronization in the network.

The electric activities of neurons could be changed when ion channel block occurs in the neurons. External forcing currents with diversity are imposed on the regular network of Hodgkin-Huxley (HH) neuron, and target waves are induced to occupy the network. The forcing current I1is imposed on neurons in a local region with m0×m0nodes in the network, neurons in other nodes are imposed with another forcing current I2. Target wave could be developed to occupy the network when the gradient forcing current (I1–I2) exceeds certain threshold, and the formation of target wave is independent of the selection of boundary condition. It is also found that the developed target wave can decrease the negative effect of ion channel block and suppress the spiral wave, and thus channel noise is also considered. The potential mechanism of formation of target wave could be that the gradient forcing current (I1–I2) generates quasi-periodical signal in local area, and the propagation of quasi-periodical signal induces target-like wave due to mutual coupling among neurons in the network.

To assess the feasibility of dose escalation guided by 18F-deoxyglucose positron emission tomography/computer tomography (18F-FDG PET/CT) for esophageal cancer (EC).

The modes of electric activities in neurons and wave propagation between neurons can be changed by using appropriate external forcing or coupling type. Based on the PSpice tool, the coupling synchronization between three Hindmarsh-Rose neurons is investigated. The neuronal circuit is also designed, and the Schmitt trigger circuit is used as peak detector by transmitting the analog signal into digital signal; thus, the rhythm of electric activities of neurons can be analyzed. By selecting different initial states (spiking or bursting), different synchronization states are found. In the case of spiking state, appropriate coupling intensity is effective in realizing rhythm synchronization and then homogenous state is observed by further increasing the coupling intensity. In the case of bursting state, rhythm synchronization is enhanced under appropriate coupling intensity while desynchronization occurs by further increasing the coupling intensity.