Building a model of a complex brain unconstrained by shared evolutionary history

Cephalopods, marine animals that include octopuses, squid and cuttlefish, have the largest and most complicated nervous systems of the invertebrate world. Octopuses, for example, have around 500 million neurons, a similar number to those of medium-sized mammals like the ferret. Unlike mammals, whose neurons are concentrated largely in their brain, cephalopods distribute their neurons throughout their bodies — octopuses have more than half their neurons in their arms. Robyn Crook is leading a project to map the neural connections in the octopus arm with a focus on the neurons that control movement, and to capture brain activity in real time as the animals move in natural ways. Crook and her colleagues will also surgically manipulate octopus arms and their suckers to test the animals’ innate and learned ability to compensate for injuries with their healthy arms. The project will also include an educational, citizen-science component by inviting San Francisco State University undergraduate students to help capture shapes of cephalopod neurons in microscopy images.

This project is part of the 2021 Neural Circuit Design cohort

Researchers in the Neural Circuit Design cohort are studying evolutionary principles in the brain circuits that control movement, focusing on animals and systems that are not traditionally studied in the laboratory. Their studies will flesh out a more complete picture of the diversity of nervous systems and motor neural circuits in the animal kingdom, as well as pinpointing common and conserved principles of motion and motor control.