Olfactory receptor neurons

The mammalian olfactory system shows an exceptional ability for rapid and accurate decoding of both the identity and concentration of odorants. In a given scene, only a handful out of millions of possible odorants are present. Yet, the mammals can effectively distinguish these odorants using the dimensionally-reduced representation provided by olfactory receptor neurons. To account for this capability, normative compressed sensing models have been proposed by previous studies. However, these models do not map cleanly onto the unique anatomy and physiology of the olfactory bulb, nor have they d

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

In all sensory systems, arrays of receptors respond to stimuli over both space and time. Whether and how the precise temporal pattern of receptor activation impacts the activity of downstream brain regions remains unclear. In the olfactory system, odors activate stereotyped spatiotemporal sequences of olfactory bulb (OB) glomeruli, whose responses reflect the activity of olfactory receptor neurons. These glomeruli project via OB mitral and tufted (M/T) cells to downstream piriform cortex (PCx), forming a shallow circuit through which to assess how temporal patterns of receptor activity are enc

Drosophila olfactory sensory hairs ("sensilla") typically house two olfactory receptor neurons (ORNs) which can laterally inhibit each other via electrical ("ephaptic") coupling. ORN pairing is highly stereotyped and genetically determined. Thus, olfactory signals arriving in the Antennal Lobe (AL) have been pre-processed by a fixed and shallow network at the periphery. To uncover the functional significance of this organization, we developed a nonlinear phenomenological model of asymmetrically coupled ORNs responding to odor mixture stimuli. We derived an analytical solution to the ORNs’ dyna

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

…while the neural circuit underlying olfactory behavior is well-described and highly stereotyped, persistent idiosyncrasy in behavior, neural coding, and neural wiring have also been described. Projection neurons (PNs), which relay odor signals sensed by

…while the neural circuit underlying olfactory behaviour is well-described and highly stereotyped, persistent idiosyncrasy in behaviour, neural coding, and neural wiring have also been described. Projection neurons (PNs), which relay odor signals sensed