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Canadian Association of Neurosciences Review: Learning at a Snail's Pace

Published online by Cambridge University Press:  02 December 2014

Kashif Parvez
Affiliation:
Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
David Rosenegger
Affiliation:
Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
Michael Orr
Affiliation:
Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
Kara Martens
Affiliation:
Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
Ken Lukowiak*
Affiliation:
Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
*
Hotchkiss Brain Institute, University of Calgary, 3330 Hospital Drive N.W., Calgary, Alberta, T2N 4N1, Canada
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Abstract:

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While learning and memory are related, they are distinct processes each with different forms of expression and underlying molecular mechanisms. An invertebrate model system, Lymnaea stagnalis, is used to study memory formation of a non-declarative memory. We have done so because: 1) We have discovered the neural circuit that mediates an interesting and tractable behaviour; 2) This behaviour can be operantly conditioned and intermediate-term and long-term memory can be demonstrated; and 3) It is possible to demonstrate that a single neuron in the model system is a necessary site of memory formation. This article reviews how Lymnaea has been used in the study of behavioural and molecular mechanisms underlying consolidation, reconsolidation, extinction and forgetting.

Résumé:

RÉSUMÉ:

Bien que l’apprentissage et la mémoire soient deux fonctions connexes, leurs processus sont distincts et chacun a des formes d’expression différentes et des mécanismes moléculaires sous-jacents différents. Nous utilisons un système dans un modèle invertébré, la Lymnaea stagnalis, pour étudier comment se forme une mémoire non déclarative. Nous avons utilisé ce modèle parce que: 1) Nous avons découvert un circuit neural qui assure la médiation d’un comportement intéressant et observable; 2) Ce comportement peut être conditionné en cours d’étude et la mémoire à moyen et à long terme peut être démontrée; 3) Il est possible de démontrer dans ce modèle qu’un seul neurone est nécessaire pour la formation de la mémoire. Cet article revoit comment la Lymnaea a été utilisée pour étudier les mécanismes comportementaux et moléculaires sous-jacents à la consolidation, à la reconsolidation, à l’extinction et à l’oubli.

Type
Review Articles
Copyright
Copyright © The Canadian Journal of Neurological 2006

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