SPLTRAK Abstract Submission
Induction phenomenon after single and brief odor learning in the newborn rabbit
Patricia Duchamp-Viret, Jiasmine Boyer, Marie Vericel, Florian Lavilla, Gerard Coureaud
Lyon Neuroscience Research Center, Bron, France

At birth blind and deaf newborn rabbits are totally contingent on their olfactory sense, which in particular drives their nipple searching and oral seizing behavior through the mammary pheromone (MP) emitted by all rabbit mother. At this early stage of life, during which acquisition of novel information contributes to adaptation and survival, any odorant paired with MP only once and for 5 min, is learned and then triggers 24h later the same sucking-related behavior as the MP itself. Here, we aimed at assessing if such an extremely rapid odor learning impacts the peripheral level reactivity, as for the “induction” process (Wysocki et al.1989). To do so, we behaviorally tested neonates and recorded electro-olfactograms (EOG); the animals were either naïve or MP-conditioned to an initially neutral odorant, ethyl maltol (EM). Recordings showed that learning increased EOG amplitudes to EM compared to those recorded in naïve animals. After learning, even if EM was the less concentrated stimulus, it became the most efficacious stimuli in 50% of recordings. This increase was selective for EM, i.e., it was not observed for a control -not learned- odorant, ethyl isobutyrate (EI). In parallel, behavioral testing revealed that the detection performances of EM in conditioned neonates were increased by a factor of 100. Further, the EM learning impacted also and differently EOG and behavioral responses to the EM+EI mixture at two distinct ratios inducing either configural or elemental perception. The results lead us to conclude that the simultaneous increase of peripheral response to EM and its detection performance fulfilled the induction process as defined by Wysocki et al. (1989). These results enrich the scarce data available about this phenomenon in mammals, particularly in neonates.