Representation of Odor Information in the Olfactory System: From Biology to an Artificial Nose

Abstract

The olfactory systems of animals as diverse as insects and primates are well-known for having extraordinary sensitivity while, at the same time, exhibiting broad discriminative abilities. These properties, often mutually exclusive in other chemical recognition systems, appear to arise from the parallel, distributed nature of the processes that underlie how odors are encoded at each level in the olfactory pathway in the brain. In this paper we describe how we have tried to characterize the physiological aspects of these processes in biological experiments, capture these processes in a computational model, and then to use these observations to design and build a biologically inspired artificial device. The Tufts Medical School Nose has achieved a degree of sensitivity and discriminability that, for certain compounds under defined conditions, approaches that of its biological parent.