title: Olfactory experience shapes the evaluation of odour similarity in ants: a behavioural and computational analysis.
abstract: Perceptual similarity between stimuli is often assessed via generalization, the response to stimuli that are similar to the one which was previously conditioned. Although conditioning procedures are variable, studies on how this variation may affect perceptual similarity remain scarce. Here, we use a combination of behavioural and computational analyses to investigate the influence of olfactory conditioning procedures on odour generalization in ants. Insects were trained following either absolute conditioning, in which a single odour (an aldehyde) was rewarded with sucrose, or differential conditioning, in which one odour (the same aldehyde) was similarly rewarded and another odour (an aldehyde differing in carbon-chain length) was punished with quinine. The response to the trained odours and generalization to other aldehydes were assessed. We show that olfactory similarity, rather than being immutable, varies with the conditioning procedure. Compared with absolute conditioning, differential conditioning enhances olfactory discrimination. This improvement is best described by a multiplicative interaction between two independent processes, the excitatory and inhibitory generalization gradients induced by the rewarded and the punished odour, respectively. We show that olfactory similarity is dramatically shaped by an individual's perceptual experience and suggest a new hypothesis for the nature of stimulus interactions underlying experience-dependent changes in perceptual similarity.
authors: Laboratory of Experimental and Comparative Ethology (LEEC), University Paris 13, Sorbonne Paris Cité, Villetaneuse, France Centre National de la Recherche Scientifique (CNRS), Research Centre on Animal Cognition (UMR5169), Toulouse, France Research Centre on Animal Cognition (UMR5169), University Paul-Sabatier, Toulouse, France.
authors: Margot
authors: M
authors: Perez
authors: Centre for Computational Neuroscience and Robotics, School of Engineering and Informatics, University of Sussex, Brighton, UK.
authors: Thomas
authors: T
authors: Nowotny
authors: Laboratory of Experimental and Comparative Ethology (LEEC), University Paris 13, Sorbonne Paris Cité, Villetaneuse, France Centre National de la Recherche Scientifique (CNRS), Research Centre on Animal Cognition (UMR5169), Toulouse, France Research Centre on Animal Cognition (UMR5169), University Paul-Sabatier, Toulouse, France.
authors: Patrizia
authors: P
authors: d'Ettorre
authors: Centre National de la Recherche Scientifique (CNRS), Research Centre on Animal Cognition (UMR5169), Toulouse, France Research Centre on Animal Cognition (UMR5169), University Paul-Sabatier, Toulouse, France martin.giurfa@univ-tlse3.fr.
authors: Martin
authors: 0000-0001-7173-769X
authors: M
authors: Giurfa
mesh_terms: D000447:Aldehydes; D000818:Animals; D001000:Ants / Q000502:physiology*; D009812:Odorants; D055696:Olfactory Perception
chemical_list: D000447:Aldehydes
keywords: ant; generalization; generalization gradient; olfactory learning; olfactory perception; perceptual modelling