We often talk about our “five senses,” and how they help us learn about the world. In the Bayer Lab we consider the fact that animals also get senses from inside of the body, and that these internal senses also affect behavior.

We consider this problem at 3 levels:

1. Behavior: How do changing internal sensations affect the way that animals interact with each other and the world?

2. Neural circuits: Which neurons send information about the body to the brain, and how do they communicate with each other?

3. Genes: What are the receptors that these internal sensory neurons use, and how might the gene expression profile of neurons change depending on what’s going on inside of the animal?

We use two models: the nematode C. elegans, and the small transparent fish D. cerebrum. We were attracted to the models because of a few things that they have in common: they’re both transparent, so we can see the neurons and internal organs that we’re interested in directly through the side of the animal, and their nervous systems are relatively small, so we can consider them comprehensively. They also have some differences: we have an unparalleled wealth of knowledge about the nervous system of C. elegans, which allows us to ask very detailed questions about how it works at the level of genes and neurons. At the level of behaviors, D. cerebrum wins for its complex social dynamics and interactions (see them in the video!).