Effects of exposure to novel taste stimuli on taste aversive conditioning (TAC) in rats

Organisms are capable of developing taste or food aversion behaviors by learning processes and avoid a food or flavor when it is related to physical discomfort, illness or some unpleasant condition. Conditioned taste aversion (CTA) is a procedure that can explain this phenomenon. It is characterized by the association of an unconditioned stimulus (US) and a conditioned stimulus (CS). Some factors that influence this process are the familiarity of the US and the intensity of the CS. Although CTA has been extensively studied, it is reported that it may be more difficult to establish an aversion to highly palatable foods, even if the published findings are inconsistent. Therefore, the aim of this study was to evaluate CTA in Wistar rats through exposure to novel gustatory stimuli (strawberry and fig flavored cookies in solid presentation) and the use of LiCl as an aversive agent. The experimental design was divided into six phases and included 24 rats assigned to four groups, two experimental and two control. It was found that the CTA procedure generated aversive behavior, causing no cookie intake during the choice test. Due to the multiple factors involved in aversion processes, these results contribute to deepen the current knowledge about the procedures that produce conditioned aversions, as these may have applications for the control of altered eating behaviors.