Stephen J Smith (physiologist)


Stephen J Smith is a Senior Investigator at the Allen Institute for Brain Science. Previously, Dr. Smith was Professor of Molecular and Cellular Physiology at the Stanford University School of Medicine.
In 1990, Smith published an article in the journal Science, which proposed that certain glial cells in the human brain known as astrocytes would be able to communicate through chemical signals, rather than electrical. By utilizing the neurotransmitter glutamate, he was able to show that these cells, which had once been perceived as inert tissue between neurons, in fact were actively communicating with the rest of the brain. This discovery showed that astrocytes likely play an important role in learning and memory. Since Smith's discovery, astrocytes have become an increasingly important part of neural research.
Smith has also been a primary leader in the development of array tomography, a proteomic imaging method of volumetric microscopy, in which ultrathin sections of a plastic-embedded tissue are sliced using an ultramicrotome, bonded in an ordered array to a glass coverslip, stained, and imaged. The public methodology for this technique was introduced in a 2007 article in the scientific journal Neuron with Kristina Micheva, and was expanded upon in a 2010 article, also in Neuron, with Micheva, Brad Busse, Nicolas Weiler, and Nancy O'Rourke. In utilizing array tomography, Smith and his colleagues created three-dimensional models of brains in mice, achieving a level of detail previously unattainable.
Smith received his Ph.D. from the University of Washington in 1977, after which he conducted postdoctoral research at the University of California, Berkeley from 1977 to 1980. He accepted a faculty position at Yale University in 1980 before relocating to Stanford in 1989.