Search
Presentation Details
| Poster #178 Neophobia Attenuation and Neuronal Response Fidelity within the Gustatory Cortex |
| Walter J. Krueger, Martin A. Raymond, John D. Boughter Jr., Max L. Fletcher II University of Tennessee Health Science Center, Memphis, TN, United States |
Food neophobia is an evolutionary trait in animals, where mice limit consumption of novel tastes until their hedonic value and aftereffects are determined. The Gustatory Cortex (GC), located in the insular cortex, is thought to be the primary regulator of neophobia, although the exact mechanism remains unclear. Recent studies have explored changes in neuronal responses through c-Fos expression or alterations in coding patterns via electrophysiological recordings in head-fixed mice. In this study, we use microendoscope calcium imaging to examine changes in both coding and the number of neurons involved. Over 600 individual neurons were tracked in eight animals over four consecutive days. Freely moving mice were presented with randomized trials of water or saccharin. Saccharin consumption was lower on Day 1 and increased over subsequent days, indicating a reduction in neophobia (AN). Statistical analysis of the mean taste-evoked change in response (ΔF) revealed no significant change in the number of saccharin-responsive GC cells or their response strength. However, further analysis revealed differences in GC coding on the neophobia day, with less consistent trial-to-trial responses for saccharin compared to subsequent days. Further, during neophobia, we found no relationship between representational similarity and licking behavior for each stimulus. However, as neophobia attenuated, this relationship stabilized, whereby representations of water and saccharin diverged as saccharin preferences emerged. These findings suggest that AN is not reflected in population changes in neuronal excitability but rather a product of multiple subtle changes in neuronal signaling, leading to greater response fidelity among neurons in the gustatory cortex as novel tastes become familiar. |