Collaborative Research: NCS-FO: Electroencephalography of Octopus bimaculoides using frequency tagging

Complex brains have evolved in only three lineages on planet earth: chordates, such as ourselves, arthropods, such as honeybees, and molluscs. Among the molluscs the octopus stands out as the brainiest and smartest. In fact, an octopus has about half a billion neurons, which is comparable to the number of neurons in the cortex of a dog.

Just as wings evolved many times, in the birds, bats and pterodons, complex brains have evolved to solve similar problems, such as vision and planning, in convergent ways. To understand universal principles of neural organization and computation, it would be beneficial to learn about the commonalities and differences between our brains and perhaps the most different brain on the planet, that of the octopus.

While some anatomical work has moved in this direction, there has been a relative paucity of work looking at octopus cognition. Because octopuses cannot talk, Behavior and objective measurements of their neural activity is one way to assess their cognition. A great deal of work has focused on observing octopus behavior.

Relatively little research has focused on octopus neurophysiology, primarily because it is a technically difficult issue to either place invasive electrodes inside an octopus, or to place non-invasive electrodes on slippery octopus skin, especially when they can easily remove them with their arms.

This project will focus on developing a non-invasive way to get measurements of octopus neural activity using underwater electroencephalography (EEG). Researchers will place the octopuses on densely packed, fixed electrodes on the floor of a container, rather than attempting to place electrodes on the octopus, as one does in human EEG. This approach takes advantage of the fact that octopuses naturally want to occupy a small crevice and peer out onto the scene, because they are opportunistic and stealthy ambush hunters, rather like cats, who themselves have to avoid being eaten.

The goal of the present work is to continue to develop co-PI Besio’s tripolar electrode technology in an interactive cycle with EEG experiments that ask questions about octopus cognition. To date, the team has struggled with various technical problems such as corrosion caused by saltwater, or artifacts in the EEG signal introduced by water. The team’s goal is to develop a fully functioning octopus EEG system over the next two years of funding, to gather sufficient preliminary data to put in a larger proposal concerning octopus cognition using EEG in the future.

This project will allow the scientific community to learn how the most 'alien' brain on earth functions, potentially teaching scientists about universal principles of neural computation, which could shed light on how human brains work and also inform design in artificial intelligence systems that could benefit society.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.