title: Brainstem lesions and gustatory function: III. The role of the nucleus of the solitary tract and the parabrachial nucleus in retention of a conditioned taste aversion in rats.
abstract: Bilateral electrolytic lesions of the nucleus of the solitary tract (NST) or ibotenic acid lesions of the pontine parabrachial nuclei (PBN) failed to disrupt retention of a preoperatively acquired conditioned taste aversion (CTA) to 0.3 M alanine. For both sham- and NST-lesioned rats, the CTA persisted following 3 nonreinforced conditioned stimulus (CS) presentations. For PBN-lesioned rats, retention was more labile. The preoperatively acquired CTA was extinguished by the 3rd nonreinforced CS exposure. When assessed postoperatively using a novel CS, NST-lesioned rats acquired a new CTA, although they were rendered anosmic with zinc sulfate (P. S. Grigson, T. Shimura, & R. Norgren, 1997). Rats with PBN lesions, however, failed to acquire a second CTA postoperatively. Thus, the PBN is essential for the acquisition of a CTA, but neither of the brainstem gustatory nuclei need be intact for the retention of a preoperatively acquired CTA.
authors.affiliation: Department of Behavioral Science, College of Medicine, The Pennsylvania State University, Hershey 17033, USA. psg6@psu.edu
authors.forename: P S
authors.initials: PS
authors.lastname: Grigson
authors.forename: T
authors.initials: T
authors.lastname: Shimura
authors.forename: R
authors.initials: R
authors.lastname: Norgren
mesh_terms: D000818:Animals; D001362:Avoidance Learning / Q000502:physiology*; D001931:Brain Mapping; D001933:Brain Stem / Q000502:physiology*; D003214:Conditioning, Classical / Q000502:physiology*; D004292:Dominance, Cerebral / Q000502:physiology; D005108:Extinction, Psychological / Q000502:physiology; D018021:Lithium Chloride / Q000633:toxicity; D008297:Male; D011939:Mental Recall / Q000502:physiology; D009434:Neural Pathways / Q000502:physiology; D011149:Pons / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012153:Retention, Psychology / Q000502:physiology*; D017552:Solitary Nucleus / Q000502:physiology*; D013649:Taste / Q000502:physiology*
chemical_list: D018021:Lithium Chloride