Possible roles of electrical synapse in temporal information processing: A computational study

Xu-Long Wang, Xiao-Dong Jiang, Pei-Ji Liang

Department of Biomedical Engineering, Shanghai Jiao Tong University.

DOI: 10.4236/jbise.2008.11005                

Abstract

Temporal information processing in the range of tens to hundreds of milliseconds is critical in many forms of sensory and motor tasks. However, little has been known about the neural mechanisms of temporal information processing. Experimental observations indicate that sensory neurons of the nervous system do not show selective response to temporal properties of external stimuli. On the other hand, temporal selective neurons in the cortex have been reported in many species. Thus, processes which realize the temporal-to-spatial transformation of neuronal activities might be required for temporal information processing. In the present study, we propose a computational model to explore possible roles of electrical synapses in processing the duration of external stimuli. Firstly, we construct a small-scale network with neurons interconnected by electrical synapses in addition to chemical synapses. Basic properties of this small-scale neural network in processing duration information are analyzed. Secondly, a large-scale neural network which is more biologically realistic is further explored. Our results suggest that neural networks with electrical synapses functioning together with chemical synapses can effectively work for the temporal-to-spatial transformation of neuronal activities, and the spatially distributed sequential neural activities can potentially represent temporal information.

Keywords

model, neural network, electrical synapse, temporal information processing

Conflicts of Interest

The authors declare no conflicts of interest.

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