Taste Memory Formation: Role of Nucleus Accumbens

L Ramirez-Lugo,F Bermudez-Rattoni,L Nunez-Jaramillo

doi:10.1093/chemse/bjl023

Abstract

When a novel taste has been associated with postingestive malaise, animals recognize this taste as aversive. This associative learning is known as conditioned taste aversion. However, when an animal consumes a novel taste and no aversive consequences follow, it becomes recognized as a safe signal, leading to an increase in its consumption in subsequent presentations. In this review, we will discuss the results related to the taste memory formation focusing particularly on the nucleus accumbens (NAcc). The NAcc keeps projections with amygdala, insular cortex, parabrachial nucleus, and nucleus of the solitary tract areas important for taste memory formation. We will review the evidence relating to how the NAcc could be involved in taste memory formation, due to its role in the taste memory trace formation and its role in the association of the conditioned stimulus-unconditioned stimulus, and finally the retrieval of taste memory. In this context, we will review the participation of the cholinergic, dopaminergic, and glutamatergic systems in the NAcc during taste memory formation.

Highlights

A biologically important type of associative learning is the conditioned taste aversion (CTA)
We demonstrated that pretraining injection of DL-2-amino-5-phosphonopentanoic acid (APV), an N-methyl-Daspartic acid (NMDA) receptor antagonist, on either nucleus accumbens (NAcc) shell or core, impaired short-term and long-term aversive taste memory, without affecting the safe taste memory formation
We have presented evidences of how the NAcc could be involved in processing the taste stimulus, as well as in the association of taste with visceral consequences

Summary

Introduction

A biologically important type of associative learning is the conditioned taste aversion (CTA). The involvement of NAcc in associative learning presents itself clearly, as well as the fact that this nucleus presents important changes in DA release as a consequence of CTA conditioning. We demonstrated that pretraining injection of DL-2-amino-5-phosphonopentanoic acid (APV), an NMDA receptor antagonist, on either NAcc shell or core, impaired short-term and long-term aversive taste memory, without affecting the safe taste memory formation.

Results

Conclusion