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Classical conditioning in earthworms employing an odorous conditioned stimulus
David Reyes-Jiménez1, María J F Abad1, Concepción Paredes-Olay1
1Department of Psychology, Universidad de Jaén, 23071, Jaén, Spain.
Abstract:
The study of associative learning in invertebrates has become an essential tool for exploring their cognitive abilities and for studying the biological bases of learning and memory. In this experiment with earthworms, we paired a rose odour conditioned stimulus (CS) with a bright light unconditioned stimulus (US). After these pairings, the head retraction response - which is initially elicited by the bright light - is eventually evoked by the rose odour. This is the first demonstration of classical conditioning of an odour in earthworms (vibrations are usually employed as CSs), using a procedure that enables us to rule out an explanation in terms of pseudoconditioning.
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