title: Multiphasic on/off pheromone signalling in moths as neural correlates of a search strategy.
abstract: Insects and robots searching for odour sources in turbulent plumes face the same problem: the random nature of mixing causes fluctuations and intermittency in perception. Pheromone-tracking male moths appear to deal with discontinuous flows of information by surging upwind, upon sensing a pheromone patch, and casting crosswind, upon losing the plume. Using a combination of neurophysiological recordings, computational modelling and experiments with a cyborg, we propose a neuronal mechanism that promotes a behavioural switch between surge and casting. We show how multiphasic On/Off pheromone-sensitive neurons may guide action selection based on signalling presence or loss of the pheromone. A Hodgkin-Huxley-type neuron model with a small-conductance calcium-activated potassium (SK) channel reproduces physiological On/Off responses. Using this model as a command neuron and the antennae of tethered moths as pheromone sensors, we demonstrate the efficiency of multiphasic patterning in driving a robotic searcher toward the source. Taken together, our results suggest that multiphasic On/Off responses may mediate olfactory navigation and that SK channels may account for these responses.
authors.affiliation: UMR7503, Laboratoire Lorrain de Recherche en Informatique et ses Applications, Centre National de la Recherche Scientifique, Vandoeuvre-lès-Nancy, France. dominique.martinez@loria.fr
authors.forename: Dominique
authors.initials: D
authors.lastname: Martinez
authors.forename: Antoine
authors.initials: A
authors.lastname: Chaffiol
authors.forename: Nicole
authors.initials: N
authors.lastname: Voges
authors.forename: Yuqiao
authors.initials: Y
authors.lastname: Gu
authors.forename: Sylvia
authors.initials: S
authors.lastname: Anton
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Rospars
authors.forename: Philippe
authors.initials: P
authors.lastname: Lucas
mesh_terms: D000818:Animals; D001070:Appetitive Behavior / Q000187:drug effects*; D001640:Bicuculline / Q000494:pharmacology; D008297:Male; D008959:Models, Neurological; D009036:Moths / Q000187:drug effects* / Q000502:physiology*; D009474:Neurons / Q000187:drug effects* / Q000502:physiology*; D010675:Pheromones / Q000494:pharmacology*; D010852:Picrotoxin / Q000494:pharmacology; D024681:Potassium Channels, Calcium-Activated / Q000378:metabolism; D015203:Reproducibility of Results
chemical_list: D001640:Bicuculline; D010675:Pheromones; D010852:Picrotoxin; D024681:Potassium Channels, Calcium-Activated