Stanford engineers working on tools to probe neurons

Engineers at Stanford University are working with neuroscientists to develop tools helping probe the inner workings of neurons.

The efforts at the NeuroFab, founded by Nicholas Melosh, an associate professor of materials science, engineering and photon science at Stanford Neurosciences Institute, could lead to better devices that interface with the brain, screen drugs for electrophysiology side effects, and understand with greater precision the electrical currents that underlie human thoughts, behaviors and memories.

"Eventually we'd like to create a toolset that would impact many neuroscience labs," Melosh was quoted as saying in a news release on Tuesday from Stanford in Northern California, on the U.S. west coast.

"Neural activity is electrical in nature and is a natural fit for engineers," he said.

Neuroscientists now have two primary methods to record cellular electrical activity. One is highly accurate, but can only record from one cell at a time, inevitably killing the cell within about two hours. The other can record long-term from an array of cells, but is not very sensitive.

Teams within the NeuroFab now are experimenting with a variety of approaches for reading electrical signals. Two of the more well-developed ones involve conductive nanomaterials, either in the form of nanopillars, which poke up into cells from below, or arrays of linear nanotubes that pass through cells like a bead on a string. And other approaches involve the optical recording of electrical fields, massively parallel interfaces based on computer chips, and membrane-fusing electrodes.

"There are all sorts of practical details to understand about cell behavior that go way beyond high school biology," said graduate student Gregory Pitner, who had experience with techniques for making highly conductive carbon nanotubes in a variety of configurations.

Working with a postdoctoral fellow in a Stanford neurology and neurological science professor's laboratory, Pitner has worked out a new design that has small troughs for the cells to grow in, containing a single nanotube leading out to a recording station. With that design, the pair needed to find that right cell type to test whether the idea works. If it succeeds, the researchers envision being able to record from any kind of conductive cell including different types of neurons or heart muscle.

By including faculty and students from many disciplines, Pitner said, the NeuroFab helps bridge gaps in knowledge and expertise.

Melosh said he hopes tools developed in the NeuroFab will enable bidirectional communication with neurons in a dish, and eventually the brain, which may start to unlock secrets of the brain by measuring from many places at once. Endit