ORGANIZERS:

Tal Kimchi, Weizmann Institute of Science
Adi Mizrahi, The Hebrew University of Jerusalem
Noam Sobol, Weizmann Institute of Science
Shlomo Wagner, University of Haifa

 

In olfaction there is a poor understanding of the link between the stimulus, its resultant neural activity, and ensuing percept. In other words, there is no scientist or perfumer who can look at a novel molecule and predict its smell, or smell a novel odor and predict its molecular structure. Olfaction is processed within a hierarchical system going from olfactory epithelium to bulb to cortex. From molecular/genetic studies we know that the olfactory epithelium consists of ~10 million receptor neurons. The olfactory receptors are G-protein coupled second-messenger dependent (GPCRs). An odorant molecule binds to the extracellular aspect of the receptor, and triggers a cascade of events that culminates in the opening of cation ion channels. This is followed by a rush of positively charged ions into the cell, which depolarizes, triggering an action potential sent to the olfactory bulb.

We know that mammals have about 1,000 different olfactory receptor subtypes, and each receptor neuron expresses only one of these. Moreover, each receptor subtype responds to a few different odorants, and each odorant activates a few different receptor subtypes. This gives rise to a vast multidimensional space for encoding smell. The olfactory receptor neurons project to the olfactory bulb, where all receptors of a given type converge to a common point called an olfactory glomerulus. Thus, the glomeruli form a type of map of olfactory information at this level. Information is then projected to the olfactory cortex where not much is known on how it is processed. The conference aims to bring together scientists who study all levels of the olfactory process, in order to help bridge the gaps between levels of processing.