期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2015
卷号：112
期号：4
页码：1190-1195
DOI：10.1073/pnas.1416573112
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：SignificanceClassical studies have been focused on understanding the role of gustatory areas in evaluating the sensory component of taste. However, recent studies have suggested an involvement of gustatory areas, specifically the insular cortex, in guiding behavior on the basis of anticipation of food. At present, however, no causal link between gustatory cortex anticipatory activity and feeding behaviors has been demonstrated. The experiments in this study combine electrophysiological, pharmacological, and optogenetic approaches to establish, for the first time to our knowledge, that cue-evoked activity in the gustatory cortex is necessary to drive food-oriented behaviors. These results demonstrate that the integration between perception and action can occur also in primary sensory areas. Reward-related circuits are fundamental for initiating feeding on the basis of food-predicting cues, whereas gustatory circuits are believed to be involved in the evaluation of food during consumption. However, accumulating evidence challenges such a rigid separation. The insular cortex (IC), an area largely studied in rodents for its role in taste processing, is involved in representing anticipatory cues. Although IC responses to anticipatory cues are well established, the role of IC cue-related activity in mediating feeding behaviors is poorly understood. Here, we examined the involvement of the IC in the expression of cue-triggered food approach in mice trained with a Pavlovian conditioning paradigm. We observed a significant change in neuronal firing during presentation of the cue. Pharmacological silencing of the IC inhibited food port approach. Such a behavior could be recapitulated by temporally selective inactivation during the cue. These findings represent the first evidence, to our knowledge, that cue-evoked neuronal activity in the mouse IC modulates behavioral output, and demonstrate a causal link between cue responses and feeding behaviors.
