UCSC physicist receives award to develop technology for neuroscience

Alan Litke, an adjunct professor of physics at the University of California, Santa Cruz, has received an award from the McKnight Endowment Fund for Neuroscience to support an interdisciplinary research project with neurobiologist E. J. Chichilnisky of the Salk Institute for Biological Studies in San Diego. The McKnight Technological Innovations in Neuroscience Award will provide $200,000 over two years to support their research.

Litke and Chichilnisky are developing technology to study how the neural network of the retina at the back of the eye processes and encodes information about the visual world and communicates it to the brain. Litke has been doing research in this area for more than a decade with support from the National Science Foundation and has been collaborating with Chichilnisky since 1997. He is also involved in experimental particle physics research at CERN in Geneva, Switzerland, and is affiliated with the Santa Cruz Institute for Particle Physics (SCIPP) at UCSC.

"This is truly interdisciplinary research, where our expertise in experimental high-energy physics can bring new possibilities to neuroscience," Litke said.

Litke and his collaborators (including other researchers at SCIPP and CERN) are adapting techniques and expertise from physics and microelectronic engineering to fabricate arrays of closely spaced microscopic electrodes and custom-designed integrated circuits. The system is based on the silicon microstrip detector technology and expertise that SCIPP researchers have pioneered and developed to study short-lived particles in high-energy physics experiments. In this project, these tools will be applied to the study of living neural networks, with current efforts focusing on the retina, a thin tissue lining the back of the eye.

Litke likens the retina to a sophisticated pixel detector that converts an input visual image into a set of highly processed electrical signals that travel up the optic nerve to the brain. He and Chichilnisky are developing a "Retinal Readout System" that will allow the simultaneous recording of signals from hundreds of retinal output neurons (the ganglion cells) while a dynamic visual image is focused on the input neurons (the photoreceptors). This system will allow them to study the neural code at the interface between the retina and the brain.

The researchers also plan to explore the applications of their research to the design of a retinal prosthetic device for restoring visual function in people with retinas damaged by disease. This aspect of their project will involve interactions with Wentai Liu, a professor of electrical engineering at UCSC and campus director of the Center for Biomimetic MicroElectronic Systems (BMES). Liu heads the engineering tasks for a major retinal prosthesis project involving several institutions. The project has produced a prototype device that has been tested in a small number of patients with promising results.

In addition, Litke and Chichilnisky expect that their investigations of the retina will enable them to apply similar technology to the study of other neural systems.

Litke's collaborators on the project include a chip design group led by CERN researcher Wladek Dabrowski of Krakow, Poland. SCIPP researchers who have made important contributions to the project include research physicist Alex Grillo, physics graduate student Matthew Grivich, engineer Sergei Kachiguine, postgraduate researcher Dumitru Petrusca, and postdoctoral physicist Alexander Sher.

The McKnight Endowment Fund for Neuroscience is an independent organization funded solely by the McKnight Foundation of Minneapolis, Minnesota. The McKnight Foundation has supported neuroscience research since 1977 and in 1986 set up the Endowment Fund, led by eminent scientists in the field, to oversee the program. Since 1987, the Endowment Fund has committed nearly $34 million for neuroscience research through a series of awards based on competitive applications.

The McKnight Foundation, founded in 1953 and endowed by William L. McKnight and Maude L. McKnight, has assets of approximately $1.9 billion and granted about $75 million in 2003. William McKnight was one of the early leaders of the 3M Company, although the foundation has no affiliation with 3M.