Uzun, Rukiye | Özer, Mahmut

Proceedings | 2017 | Istanbul University - Journal of Electrical and Electronics Engineering17 , pp.3069 - 3073

In this paper; the effects of autapse (a kind of self-synapse formed between the axon of the soma of a neuron and its own dendrites) and ion channel blockage on the firing regularity of a biological small-world neuronal network, consists of stochastic Hodgkin-Huxley neurons, are studied. In this study, it is assumed that all of the neurons on the network have a chemical autapse and a constant membrane area. Obtained results indicate that there are different effects of channel blockage and parameters of the autapse on the regularity of the network, thus on the temporal coherence of the network. It is found that the firing regularity . . .of the network is decreased with the sodium channel blockage while increased with potassium channel blockage. Besides, it is determined that regularity of the network augments with the conductance of the autapse Daha fazlası Daha az

Baysal, Veli | Yılmaz, Ergin | Özer, Mahmut

Article | 2017 | Istanbul University - Journal of Electrical and Electronics Engineering17 , pp.3081 - 3085

In this paper, the effects of autapse, a kind of synapse formed between the axon or soma of a neuron and its own dendrite, on the transmission of weak signal are investigated in scale-free neuronal networks. In the study, we consider that each neuron has an autapse modelled as chemical synapse. Then, a weak signal that is thought to carry information or an unwanted activity such as virus is applied to all neurons in the network. It is seen that the autapse with its small conductance values can slightly increases the transmission of weak signal across the network when the autaptic time delay is equal to the intrinsic oscillation peri . . .od of the Hodgkin-Huxley neuron. Interestingly, when the autaptic time delay becomes equal to half of this intrinsic period or its integer multiples the autapse can prominently blocks the weak signal transmission. Also, as the autaptic conductance is increased the weak signal transmission is completely impeded by the autapse with its proper auatptic time delays. One consider that the weak signal is an unwanted or virius threatening the whole network, this autaptic mechanism is an efficient way to protect the network from attacks Daha fazlası Daha az