Effect of temperature on synchronization of scale-free neuronal network

The ambient temperature and the time delay of signal transmission are very important influences on the synchronization behavior of neuronal networks. In this paper, a neuronal network with the power-law degree distribution is constructed using a Hodgkin-Huxley model containing a temperature modulation factor and noise, and neurons at each node of the scale-free network are interconnected by electrical and chemical synapses, respectively. In scale-free networks with different ambient temperatures, the absence of time delay causes the synchronization of networks connected by both synaptic types to increase with coupling strength at lower temperatures, while the opposite is shown for networks connected by chemical synapses at higher temperatures. Networks connected by both synaptic types show multiple synchronization transitions when there is the time delay. Surprisingly, there is a temperature threshold for scale-free networks connected by chemical synapses, beyond which synchronization becomes very poor. By introducing the coefficient of variation and the mean inter-spikes intervals, it is found that the emergence of temperature thresholds for networks connected by chemical synapses is caused by a further increase in the difference in firing frequency of neurons due to increasing temperature. Finally, the generality of the results and mechanisms studied in scale-free networks is verified by investigating the effects of different network scales on synchronization.

Automated summary

The ambient temperature and the time delay of signal transmission have important influences on the synchronization behavior of neuronal networks. Both electrical and chemical synapses contribute to the synchronization of scale-free networks, with different effects at different temperatures. The presence of time delay leads to multiple synchronization transitions in both types of synapses. Surprisingly, there is a temperature threshold for synchronization in networks connected by chemical synapses. The generality of the results and mechanisms is verified by investigating the effects of different network scales on synchronization.