Topic: sensilla

In insects, Olfactory Receptor Neurons ('ORNs') are grouped together into sensory hairs ('sensilla') in a stereotypical manner. Grouped ORNs: (i) antagonistically regulate the same behaviors, (ii) mutually inhibit each other via electrical interactions, and (iii) have a systematic size-asymmetry, resulting in asymmetric inhibitory interactions. The functional significance of this highly conserved organization is not known. We constructed a phenomenological model of nonlinearly coupled ORNs, which shows that inhibition between ORNs transiently amplifies the hedonic value ('valence') of an odor

Olfactory Receptor Neurons (ORNs) in insects are tightly packed into sensory hairs (sensilla), where they are electrically coupled. This organization is highly stereotyped and genetically determined. Electrical (`ephaptic') coupling between neurons within the same hair results in strong lateral inhibition, posing questions about the functional significance of the stereotyped organization. We developed a phenomenological model of coupled ORNs responding to odor mixture stimuli. Our model includes two forms of nonlinearity, essential to capture the nature of the coupling. First, ephaptic interac