AUTHOR=Rojas Sebastián , Diaz-Galarce Raúl , Jerez-Baraona Juan Manuel , Quintana-Donoso Daisy , Moraga-Amaro Rodrigo , Stehberg Jimmy TITLE=The insula modulates arousal-induced reluctance to try novel tastes through adrenergic transmission in the rat JOURNAL=Frontiers in Behavioral Neuroscience VOLUME=9 YEAR=2015 URL=https://www.frontiersin.org/journals/behavioral-neuroscience/articles/10.3389/fnbeh.2015.00164 DOI=10.3389/fnbeh.2015.00164 ISSN=1662-5153 ABSTRACT=

Reluctance to try novel tastes (neophobia) can be exacerbated in arousing situations, such as when children are under social stress or in rodents, when the new taste is presented in a high arousal context (HA) compared to a low arousal context (LA). The present study aimed at determining whether adrenergic transmission at the Insula regulates the reluctance to try novel tastes induced by arousing contexts. To this end, a combination of systemic and intra-insular manipulations of adrenergic activity was performed before the novel taste (saccharin 0.1%) was presented either in LA or HA contexts in rats. Our results show that systemic adrenergic activity modulates reluctance to try novel tastes. Moreover, intra-insular microinjections of propranolol or norepinephrine (NE) were found to modulate the effects of arousing contexts on reluctance to try novel tastes. Finally, intra-insular propranolol blocked epinephrine-induced increased reluctance, while intra-insular NE blocked oral propranolol-induced decreases in reluctance and increased the reluctance to try novel tastes presented in low arousing contexts. In conclusion, our results suggest that the insula is a critical site for regulating the effects of arousal in the reluctance to try novel tastes via the adrenergic system.