Mriganka Sur - Work

Work

Sur is a pioneer in the study of brain plasticity and its mechanisms. Using experimental and theoretical approaches, his laboratory studies developmental plasticity and the dynamic changes in mature cortical networks during information processing, learning and memory. His laboratory has discovered fundamental principles by which neurons of the cerebral cortex are wired during development and change dynamically in adulthood. In landmark experiments, he “rewired” the brain to explore how the environment influences the development of cortical circuits. The retina, which normally projects to the visual cortex, was induced to project to structures that normally process hearing. Visual input altered the development of neuronal connections in the auditory cortex, thus enabling animals to use their "hearing" cortex to "see."

These findings have implications for restoring function after brain damage and for constructing neural prostheses for recovery from stroke or trauma. The Sur laboratory also studies genes involved in constructing the cerebral cortex, and the ways in which gene networks are influenced by brain activity. These studies are providing important insights into childhood disorders such as autism. Stemming from this work, a pharmacological treatment for Rett Syndrome has entered clinical trials.

By imaging calcium responses of single neurons and astrocytes in vivo using high resolution imaging methods, his laboratory has discovered that astrocytes have remarkably specific functional properties and mediate blood flow to active brain regions. This work has revealed the mechanism for noninvasive brain imaging methods such as functional magnetic resonance imaging (fMRI).

The Sur laboratory has also shown how neurons of the mature visual cortex alter their responses dynamically based on the configuration of visual stimuli in space and time. The laboratory studies the mechanisms by which visual neurons at the earliest stages of cortical processing are influenced not only by “bottom up” visual inputs but also in “top down” manner by mental state, including attention and expectation. These studies provide fundamental information about higher brain mechanisms, including those involved in vision, cognition, and learning.