Effect of lateral inhibition and cortical feedback in the model of olfactory bulb

The olfactory bulb is the first information processing unit in the olfactory pathway, and it is considered to discriminate the difference between odors, but the mechanism underlying the odorant discrimination process is not understood clearly. Recent experimental results show that each odor is represented as the different local spatial pattern of neuronal activity [Mori et al., 1992]. Due to the anatomical structure of the bulb, such local patterns are generated by the lateral inhibition between mitral-granule synaptic interaction. We have modeled a neural network model of the olfactory bulb, and study the odorant discrimination process. In addition to the peripheral input from the receptor neurons, the olfactory bulb receives centrifugal input from olfactory cortex as well as other cortical regions. This cortical feedback also contributes to the formation of local spatial patterns.