Skip to main content

Research Repository

See what's under the surface

Advanced Search

Catecholaminergic depletion in nucleus accumbens enhances trace conditioning

Nelson, Andrew J.D.; Thur, Karen E.; Spicer, C.; Marsden, C.A.; Cassaday, Helen J.

Authors

Andrew J.D. Nelson

Karen E. Thur

C. Spicer

C.A. Marsden

Helen J. Cassaday



Abstract

Purpose: To examine the effect of dopamine depletion in nucleus accumbens on trace conditioning; to distinguish the role of core and shell sub-regions, as far as possible. Material/Methods: 6-hydroxydopamine was used to lesion dopamine terminals within the core and shell accumbens. Experiment 1 assessed conditioning to a tone conditioned stimulus that had previously been paired with footshock (unconditioned stimulus) at a 30s trace interval. Experiment 2 subsequently assessed contiguous conditioning (at 0s trace) using a light conditioned stimulus directly followed by the unconditioned stimulus.

Results: Both sham and shell-lesioned animals showed the normal trace effect of reduced conditioning to the trace conditioned stimulus but 6-hydroxydopamine injections targeted on the core subregion of the nucleus accumbens abolished this effect and enhanced conditioning to the trace conditioned stimulus. However, the depletion produced by this lesion placement extended to the shell. In Experiment 2 (at 0s trace), there was no effect of either lesion placement as all animals showed comparable levels of conditioning to the light conditioned stimulus. Neurochemical analysis across core, shell and comparison regions showed some effects on noradrenalin as well as dopamine.

Conclusions: The pattern of changes in noradrenalin did not systematically relate to the observed behavioural changes after core injections. The pattern of changes in dopamine suggested that depletion in core mediated the increased conditioning to the trace conditioned stimulus seen in the present study. However, the comparison depletion restricted to the shell subregion was less substantial, and a role for secondarily affected brain regions cannot be excluded.

Journal Article Type Article
Publication Date Jun 1, 2011
Journal Advances in Medical Sciences
Electronic ISSN 1896-1126
Publisher Elsevier
Peer Reviewed Peer Reviewed
Volume 56
Issue 1
APA6 Citation Nelson, A. J., Thur, K. E., Spicer, C., Marsden, C., & Cassaday, H. J. (2011). Catecholaminergic depletion in nucleus accumbens enhances trace conditioning. Advances in Medical Sciences, 56(1), doi:10.2478/v10039-011-0014-2
DOI https://doi.org/10.2478/v10039-011-0014-2
Keywords conditioned emotional response; associative learning; 6-hydroxydopamine
Publisher URL http://www.degruyter.com/view/j/ams.2011.56.issue-1/v10039-011-0014-2/v10039-011-0014-2.xml
Copyright Statement Copyright information regarding this work can be found at the following address: http://creativecommons.org/licenses/by-nc-nd/4.0

Files

Cassaday_Catecholaminergic_depletion_in_nucleus_accumbens_enhances_trace.pdf (847 Kb)
PDF

Copyright Statement
Copyright information regarding this work can be found at the following address: http://creativecommons.org/licenses/by-nc-nd/4.0





You might also like



Downloadable Citations

;