James McHugh in his book Sandalwood and Carrion: Smell in Indian Religion and Culture writes
“We might begin by considering the notion that smell is primitive, bestial and sensual; an animal sense that has been diminished in adopting the human upright posture, and a sense that, if overdeveloped, marks one as a savage.”
Although slightly incorrect, his statements are indicative of our so little understanding of sense of smell. The odor molecules pervade our living universe, literally swept by the air that we breathe in to the sensory organ. The sampling process to de-correlation of the sensory signals, the whole olfactory pathway is filled with mysteries. The first of them being, which molecules interact or which part of molecules is recognized by which receptor ? The others being, Do the similar receptors converge at a single place or is it diverse? Where do these signals go and what do they evoke ? Alas, the only non-invasive and simplest way of knowing what it felt like to smell something are verbal descriptions by subjects or perfumists. These are considered to be notoriously varied in nature to the extent that some researchers have concluded the language abilities to be uncorrelated with olfactory experience. The research and the reports thereby are concentrated in English as vocabulary expression of smell.
The availability of data and modern statistical techniques coupled with computing resources has led to unprecedented advancement in some fields like natural language processing. In this series of blogs I will be first reporting the olfactory data gathering techniques, the data bases, their analyses and statistical methods to analyze the bigger problem of olfactory stimulus-percepts. I will be attempting to find sense in verbal descriptions of smell using some of the famous techniques and design a co-occurrence network, where I will define the concept of perceptual classes and communities.
I also attempt to gather as many odoriferous molecules as possible, along with their percepts and physico-chemical properties and hence find statistical regularities in perceptual and physico-chemical space. Kindly report any mistake that you may think has crept into the database.
riteshkumarrai 