Taste Neophobia, Latent Inhibition of Taste Aversion and Object Recognition Memory in Adolescent Rats

Background: Adolescence in mammals is a period marked by increased novelty-seeking and enhanced responsiveness to the stressful properties of novel stimuli. Despite the need to taste potentially toxic novel foods during the adolescent growth spurt, there has been little study of taste neophobia and its attenuation. Method: Four experiments were carried out to compare taste neophobia and related memory processes in male and female adolescent (PND28) and adult (PND70) Wistar rats. Experiments 1 and 2 evaluated attenuation of taste neophobia to cider vinegar (3%) and sodium saccharin (0.1%) solutions were evaluated. Additionally, to test the role of memory in neophobia during adolescence, latent inhibition of taste aversion and object recognition memory were assessed in Experiment 3 and Experiment 4, respectively. Results: Adolescent and adult rats exhibited taste neophobia to the saccharin solution but adolescent rats required more exposure trials than adults to recognize the vinegar solution as safe. Both groups exhibited similar latent inhibition of taste aversion and object recognition memory. No sex effect was significant. Conclusions: Contrary to the accepted view associating adolescence with reduced neophobia, adolescent rats exhibited taste neophobia which even increased when sour tastes were encountered.