title: Respective role of the dorsal hippocampus and the entorhinal cortex during the recombination of previously learned olfactory-tactile associations in the rat.
abstract: The hippocampal formation has been extensively described as a key component for object recognition in conjunction with place and context. The present study aimed at describing neural mechanisms in the hippocampal formation that support olfactory-tactile (OT) object discrimination in a task where space and context were not taken into account. The task consisted in discriminating one baited cup among three, each of them presenting overlapping olfactory or tactile elements. The experiment tested the involvement of the entorhinal cortex (EC) and the dorsal hippocampus (DH) in the acquisition of this cross-modal task, either with new items or with familiar but recombined items. The main results showed that DH inactivation or cholinergic muscarinic blockade in the DH selectively and drastically disrupted performance in the recombination task. EC inactivation impaired OT acquisition of any OT combinations while cholinergic blockade only delayed it. Control experiments showed that neither DH nor EC inactivation impaired unimodal olfactory or tactile tasks. As a whole, these data suggest that DH-EC interactions are of importance for flexibility of cross-modal representations with overlapping elements.
authors.affiliation: Centre de Recherche en Neuroscience de Lyon, Team CMO, CNRS UMR 5292, INSERM U 1028, Université Lyon 1, Université de Lyon, 69366 Lyon, France.
authors.forename: Lise
authors.initials: L
authors.lastname: Boisselier
authors.affiliation: Centre de Recherche en Neuroscience de Lyon, Team CMO, CNRS UMR 5292, INSERM U 1028, Université Lyon 1, Université de Lyon, 69366 Lyon, France.
authors.forename: Barbara
authors.initials: B
authors.lastname: Ferry
authors.affiliation: Centre de Recherche en Neuroscience de Lyon, Team CMO, CNRS UMR 5292, INSERM U 1028, Université Lyon 1, Université de Lyon, 69366 Lyon, France.
authors.forename: Rémi
authors.initials: R
authors.lastname: Gervais
mesh_terms: D000779:Anesthetics, Local / Q000494:pharmacology; D000818:Animals; D001245:Association Learning / Q000187:drug effects / Q000502:physiology*; D018680:Cholinergic Antagonists / Q000494:pharmacology; D004193:Discrimination Learning / Q000187:drug effects / Q000502:physiology*; D018728:Entorhinal Cortex / Q000187:drug effects / Q000502:physiology*; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D008012:Lidocaine / Q000494:pharmacology; D008297:Male; D009434:Neural Pathways / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012601:Scopolamine / Q000494:pharmacology; D012903:Smell / Q000502:physiology*; D014110:Touch / Q000502:physiology*; D014633:Valine / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: D000779:Anesthetics, Local; D018680:Cholinergic Antagonists; D018691:Excitatory Amino Acid Antagonists; C056639:2-amino-5-phosphopentanoic acid; D008012:Lidocaine; D012601:Scopolamine; D014633:Valine