Vestibular loss promotes procedural response during a spatial task in rats

Authors

  • Marie-Laure Machado,

    Corresponding author
    1. Normandie University, France
    2. UNICAEN, COMETE, Caen, France
    3. Inserm, U 1075 COMETE, Caen, France
    • Correspondence to: Marie-Laure Machado; U 1075 COMETE UMR-M UCBN/INSERM, UFR Médecine, Avenue de la Côte de Nacre, 14032 Caen Cedex, France. E-mail: machado-ml@phycog.org

    Search for more papers by this author
  • Véronique Lelong-Boulouard,

    1. Normandie University, France
    2. UNICAEN, COMETE, Caen, France
    3. Inserm, U 1075 COMETE, Caen, France
    4. CHU de Caen, Department of Pharmacology, Caen, CS, France
    Search for more papers by this author
  • Bruno Philoxene,

    1. Normandie University, France
    2. UNICAEN, COMETE, Caen, France
    3. Inserm, U 1075 COMETE, Caen, France
    Search for more papers by this author
  • Audrey Davis,

    1. Normandie University, France
    2. UNICAEN, COMETE, Caen, France
    3. Inserm, U 1075 COMETE, Caen, France
    Search for more papers by this author
  • Pierre Denise,

    1. Normandie University, France
    2. UNICAEN, COMETE, Caen, France
    3. Inserm, U 1075 COMETE, Caen, France
    4. CHU de Caen, Department of Functional Exploration, Caen, CS, France
    Search for more papers by this author
  • Stéphane Besnard

    1. Normandie University, France
    2. UNICAEN, COMETE, Caen, France
    3. Inserm, U 1075 COMETE, Caen, France
    4. CHU de Caen, Department of Functional Exploration, Caen, CS, France
    Search for more papers by this author

ABSTRACT

Declarative memory refers to a spatial strategy using numerous sources of sensory input information in which visual and vestibular inputs are assimilated in the hippocampus. In contrast, procedural memory refers to a response strategy based on motor skills and familiar gestures and involves the striatum. Even if vestibular loss impairs hippocampal activity and spatial memory, vestibular-lesioned rats remain able to find food rewards during complex spatial memory task. Since hippocampal lesions induce a switch from declarative memory to procedural memory, we hypothesize that vestibular-lesioned rats use a strategy other than that of hippocampal spatial response to complete the task and to counterbalance the loss of vestibular information. We test, in a reverse T-maze paradigm, the types of strategy vestibular-lesioned rats preferentially uses in a spatial task. We clearly demonstrate that all vestibular-lesioned rats shift to a response strategy to solve the spatial task, while control rats use spatial and response strategies equally. We conclude that the loss of vestibular informations leading to spatial learning impairments is not offset at the hippocampus level by integration process of other sense mainly visual informations; but favors a response strategy through procedural memory most likely involving the striatum, cerebellum, and motor learning. © 2014 Wiley Periodicals, Inc.

Ancillary