Odour recognition and segmentation by a model olfactory bulb and cortex.

Z Li; J Hertz

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PubMed · 10735530

Odour recognition and segmentation by a model olfactory bulb and cortex.

Z Li·J Hertz

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Abstract

We present a model of an olfactory system that performs odour segmentation. Based on the anatomy and physiology of natural olfactory systems, it consists of a pair of coupled modules, bulb and cortex. The bulb encodes the odour inputs as oscillating patterns. The cortex functions as an associative memory: when the input from the bulb matches a pattern stored in the connections between its units, the cortical units resonate in an oscillatory pattern characteristic of that odour. Further circuitry transforms this oscillatory signal to a slowly varying feedback to the bulb. This feedback implements olfactory segmentation by suppressing the bulbar response to the pre-existing odour, thereby allowing subsequent odours to be singled out for recognition.

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Afferent Pathways Animals Computer Simulation Discrimination Learning Feedback Mammals Neural Networks, Computer Odorants Olfactory Bulb Olfactory Pathways Smell Journal Article

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Z Li, J Hertz. 2000. Odour recognition and segmentation by a model olfactory bulb and cortex.. https://pubmed.ncbi.nlm.nih.gov/10735530/

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