Reduced dopamine function within the medial shell of the nucleus accumbens enhances latent inhibition

Latent inhibition (LI) manifests as poorer conditioning to a CS that has previously been presented without consequence. There is some evidence that LI can be potentiated by reduced mesoaccumbal dopamine (DA) function but the locus within the nucleus accumbens of this effect is as yet not firmly esta...

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Main Authors: Nelson, Andrew J.D., Thur, Karen E., Horsley, R.R., Spicer, C, Marsden, C.A., Cassaday, Helen J.
Format: Article
Published: Elsevier 2011
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Online Access:https://eprints.nottingham.ac.uk/3206/
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author Nelson, Andrew J.D.
Thur, Karen E.
Horsley, R.R.
Spicer, C
Marsden, C.A.
Cassaday, Helen J.
author_facet Nelson, Andrew J.D.
Thur, Karen E.
Horsley, R.R.
Spicer, C
Marsden, C.A.
Cassaday, Helen J.
author_sort Nelson, Andrew J.D.
building Nottingham Research Data Repository
collection Online Access
description Latent inhibition (LI) manifests as poorer conditioning to a CS that has previously been presented without consequence. There is some evidence that LI can be potentiated by reduced mesoaccumbal dopamine (DA) function but the locus within the nucleus accumbens of this effect is as yet not firmly established. Experiment 1 tested whether 6-hydroxydopamine (6-OHDA)-induced lesions of DA terminals within the core and medial shell subregions of the nucleus accumbens (NAc) would enhance LI under conditions that normally disrupt LI in controls (weak pre-exposure). LI was measured in a thirst motivated conditioned emotional response procedure with 10 pre-exposures (to a noise CS) and 2 conditioning trials. The vehicle-injected and core-lesioned animals did not show LI and conditioned to the pre-exposed CS at comparable levels to the non-pre-exposed controls. 6-OHDA lesions to the medial shell, however, produced potentiation of LI, demonstrated across two extinction tests. In a subsequent experiment, haloperidol microinjected into the medial shell prior to conditioning similarly enhanced LI. These results underscore the dissociable roles of core and shell subregions of the NAc in mediating the expression of LI and indicate that reduced DA function within the medial shell leads to enhanced LI.
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spelling nottingham-32062020-05-04T20:23:28Z https://eprints.nottingham.ac.uk/3206/ Reduced dopamine function within the medial shell of the nucleus accumbens enhances latent inhibition Nelson, Andrew J.D. Thur, Karen E. Horsley, R.R. Spicer, C Marsden, C.A. Cassaday, Helen J. Latent inhibition (LI) manifests as poorer conditioning to a CS that has previously been presented without consequence. There is some evidence that LI can be potentiated by reduced mesoaccumbal dopamine (DA) function but the locus within the nucleus accumbens of this effect is as yet not firmly established. Experiment 1 tested whether 6-hydroxydopamine (6-OHDA)-induced lesions of DA terminals within the core and medial shell subregions of the nucleus accumbens (NAc) would enhance LI under conditions that normally disrupt LI in controls (weak pre-exposure). LI was measured in a thirst motivated conditioned emotional response procedure with 10 pre-exposures (to a noise CS) and 2 conditioning trials. The vehicle-injected and core-lesioned animals did not show LI and conditioned to the pre-exposed CS at comparable levels to the non-pre-exposed controls. 6-OHDA lesions to the medial shell, however, produced potentiation of LI, demonstrated across two extinction tests. In a subsequent experiment, haloperidol microinjected into the medial shell prior to conditioning similarly enhanced LI. These results underscore the dissociable roles of core and shell subregions of the NAc in mediating the expression of LI and indicate that reduced DA function within the medial shell leads to enhanced LI. Elsevier 2011-03 Article PeerReviewed Nelson, Andrew J.D., Thur, Karen E., Horsley, R.R., Spicer, C, Marsden, C.A. and Cassaday, Helen J. (2011) Reduced dopamine function within the medial shell of the nucleus accumbens enhances latent inhibition. Pharmacology Biochemistry and Behavior, 98 (1). pp. 1-7. ISSN 0091-3057 Latent inhibition; Nucleus accumbens; Core; Shell; Dopamine http://www.sciencedirect.com/science/article/pii/S0091305710003631 doi:10.1016/j.pbb.2010.11.025 doi:10.1016/j.pbb.2010.11.025
spellingShingle Latent inhibition; Nucleus accumbens; Core; Shell; Dopamine
Nelson, Andrew J.D.
Thur, Karen E.
Horsley, R.R.
Spicer, C
Marsden, C.A.
Cassaday, Helen J.
Reduced dopamine function within the medial shell of the nucleus accumbens enhances latent inhibition
title Reduced dopamine function within the medial shell of the nucleus accumbens enhances latent inhibition
title_full Reduced dopamine function within the medial shell of the nucleus accumbens enhances latent inhibition
title_fullStr Reduced dopamine function within the medial shell of the nucleus accumbens enhances latent inhibition
title_full_unstemmed Reduced dopamine function within the medial shell of the nucleus accumbens enhances latent inhibition
title_short Reduced dopamine function within the medial shell of the nucleus accumbens enhances latent inhibition
title_sort reduced dopamine function within the medial shell of the nucleus accumbens enhances latent inhibition
topic Latent inhibition; Nucleus accumbens; Core; Shell; Dopamine
url https://eprints.nottingham.ac.uk/3206/
https://eprints.nottingham.ac.uk/3206/
https://eprints.nottingham.ac.uk/3206/