Biological Mechanisms of Food-Related Decision Making

Consumption or rejection of food are outcomes of a hierarchical multisensory decision- making process. Food-related decisions must frequently resolve conflicts, such as whether to consume a fruit that is visually appealing but smells rotten. Such decisions require neural substrates for evaluating characteristics of food—appearance, smell, taste, touch—and comparing/contrasting such characteristics to decide whether to approach, assess, and/or consume. We study food-related decision making in Drosophila melanogaster flies and Caenorhabditis elegans nematode worms, which have simpler behavioral repertoires, are highly experimentally tractable, and have proven utility at generating biological insights of relevance to mammalian model systems and human beings. The proposed Drosophila studies provide detailed mechanistic understanding of the circuit substrates, neuromodulatory pathways, and neural encoding of sweet/bittersweet food choice in Drosophila, and a foundation for research more broadly into decision making under conflicting information. The proposed C. elegans studies provide extensive evidence of worm color detection and the underlying cellular/molecular mechanisms, revealing pathways that could underlie an evolutionarily ancient opsin-independent color detection system present in other animals including mammals.