Meeting Abstract

106.1  Saturday, Jan. 7  Numerical Simulations of Odorant Detection by Crustacean Olfactory Hair Arrays SCHUECH, Rudi*; STACEY, Mark; KOEHL, Mimi; Univ. of California, Berkeley rudis@berkeley.edu

Many marine crustaceans flick sensory antennules through the water to actively sample turbulent odor plumes. An important step in odorant detection is the transport of odorant molecules from the filamentous structures making up the plume to the individual chemosensory hairs (aesthetascs) arrayed on the antennules. Through processes such as advection and diffusion, the geometry and flicking kinematics of an animal's olfactory appendages affect the time course of odorant arrival to neurons, and thus how the animal perceives its odor landscape. We numerically modeled both flow and odorant transport as an odorant filament is sampled by a simple row of flux-detecting sensory hairs. Metrics of odorant flux such as peak flux, peak onset slope, total flux, and duration of stimulation were quantified for both individual hairs and the aggregate array as sampling kinematics and array geometry were varied. The relationship between array size and odorant flux is exhibits several peculiarities, and behavior can be completely opposite at different sampling speeds. These transitions in fundamental behavior suggest both a new advantage of flicking, and the non-intuitive possibility of appendages whose peak flux metrics change little with number of hairs despite increasing surface area. Neurons near the edges of an aesthetasc array experience higher peak metrics and total flux than those near the middle of the array, but will be stimulated for less time; such variation may be important in the context of spatial plume sampling by aesthetasc arrays.