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Published on: June 22, 2015
Fos-like immunoreactivity in locus coeruleus after classical conditioning of the rabbit's nictitating membrane
P Carrive1, E J Kehoe, M Macrae
1School of Psychology, University of New South Wales, Sydney, Australia. p.carrive@unsw.edu.au
Abstract:
We investigated the changes in Fos-like immunoreactivity in the locus coeruleus (LC) after classical conditioning of the rabbit's nictitating membrane. Specifically, we compared unpaired versus paired presentations of a tone conditioned stimulus (CS) and a tactile unconditioned stimulus (US; near the eye). After two training sessions, only paired presentations resulted in acquisition of a conditioned response. This was associated with comparatively less LC Fos expression than with unpaired presentations. Similar observations have been reported for the ventrolateral medulla which is a major source of afferents to LC. The present results are consistent with a role of LC in attention and learning: activity increases as the animal attends to the CS and US. When the relationship between CS and US has been established, LC activity decreases.
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