Multiphasic on/off pheromone signalling in moths as neural correlates of a search strategy

Dominique D. Martinez (1) , Antoine A. Chaffiol (2) , Nicole N. Voges (1) , Yuqiao Y. Gu (2) , Sylvia Anton (3) , Philippe P. Lucas (2)

1 LORIA - Laboratoire Lorrain de Recherche en Informatique et ses Applications
2 PISC - Physiologie de l'Insecte : Signalisation et Communication
3 RCIM - Récepteurs et Canaux Ioniques Membranaires

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.

Domaines: Sciences agricoles

Dominique D. Martinez, Antoine A. Chaffiol, Nicole N. Voges, Yuqiao Y. Gu, Sylvia Anton, et al.. Multiphasic on/off pheromone signalling in moths as neural correlates of a search strategy. PLoS ONE, 2013, 8 (4), pp.e61220. ⟨10.1371/journal.pone.0061220⟩. ⟨hal-01001334⟩