Research reportAmygdala-gustatory insular cortex connections and taste neophobia

To examine whether communication between the amygdala and gustatory insular cortex (GC) is required for normal performance of taste neophobia, three experiments were conducted. In Experiment 1, rats with asymmetric unilateral lesions of the basolateral amygdala (BLA) and the GC displayed elevated intake of a novel saccharin solution relative to control subjects. However, an attenuation of neophobia was not found following asymmetric unilateral lesions of the GC and medial amygdala (MeA; Experiment 2) or of the MeA and BLA (Experiment 3). This pattern of results indicates that the BLA and GC functionally interact during expression of taste neophobia and that the MeA functionally interacts with neither the BLA nor the GC. Research is needed to further characterize the nature of the involvement of the MeA in taste neophobia and to determine the function of the BLA-GC interaction during exposure to a new taste.

► We examined whether amygdala and gustatory insular cortex connections are required for taste neophobia. ► Asymmetric unilateral lesions of the BLA and GC attenuated taste neophobia. ► Asymmetric unilateral lesions of the GC-MeA or MeA-BLA had no influence on taste neophobia. ► We conclude that the BLA and GC operate as a unit whereas the MeA function independently in processing a novel tastant.