Functional Connectomics in C. elegans

The complete structure and connectivity of the Caenorhabditis elegans nervous system was first published in 1986. The ‘mind of a worm’ was the first organism to have its nervous system to be reconstructed at the level of synapses, and represented a critical milestone considering today it remains the only organism to be mapped to that level of connection. Recently, the extrasynaptic connectome of neuropeptides and monoamines has been described. This review discusses recent technological advances used to perturb whole-organism neuronal function, such as: whole brain imaging, optogenetics, sonogenetics and mutant analysis, which have allowed for interrogations of both local and global neural circuits, leading to different behaviors. A better understanding of a whole organism requires combining experimental datasets with biophysical neuronal modelling, and behavioral quantification. Combining these approaches will provide a complete understanding of the worm nervous system and shed light into how networks function and interact with the synaptic network to modulate information processing and behavioral output.