Dendrodendritic Inhibition and Simulated Odor Responses in a Detailed Olfactory Bulb Network Model
Dendrodendritic Inhibition and Simulated Odor Responses in a Detailed Olfactory Bulb Network Model
By Andrew Davison, Jianfeng Feng, and David Brown
Journal of Neurophysiology (2003)
Abstract Paper

Andrew  Davison

UNIC, CNRS UPR 3293

France

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This is a model of the mammalian olfactory bulb for the NEURON simulator. The model contains only mitral and granule cells. It is intended that the properties of the network can be explored by changing the files parameters_<xxx>.hoc and experiment_<xxx>.hoc. It should not be necessary to change the other files. After compiling the mod files, start the simulation by running init.hoc Type show_results() if after running the odour stimulus simulation the mitral cell spike time histogram graph is empty.
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August 09, 2012
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Neuron 7.1
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October 08, 2012
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Abstract
In the olfactory bulb, both the spatial distribution and the temporal structure of neuronal activity appear to be important for processing odor information, but it is currently impossible to measure both of these simultaneously with high resolution and in all layers of the bulb. We have developed a biologically realistic model of the mammalian olfactory bulb, incorporating the mitral and granule cells and the dendrodendritic synapses between them, which allows us to observe the network behavior in detail. The cell models were based on previously published work. The attributes of the synapses were obtained from the literature. The pattern of synaptic connections was based on the limited experimental data in the literature on the statistics of connections between neurons in the bulb. The results of simulation experiments with electrical stimulation agree closely in most details with published experimental data. This gives confidence that the model is capturing features of network interactions in the real olfactory bulb. The model predicts that the time course of dendrodendritic inhibition is dependent on the network connectivity as well as on the intrinsic parameters of the synapses. In response to simulated odor stimulation, strongly activated mitral cells tend to suppress neighboring cells, the mitral cells readily synchronize their firing, and increasing the stimulus intensity increases the degree of synchronization. Preliminary experiments suggest that slow temporal changes in the degree of synchronization are more useful in distinguishing between very similar odorants than is the spatial distribution of mean firing rate.
Davison, A., J. Feng, and D. Brown, "Dendrodendritic Inhibition and Simulated Odor Responses in a Detailed Olfactory Bulb Network Model", Journal of Neurophysiology , 90, 1921-1935.
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