Martha Constantine-Paton, Ph.D. ’76, Neurobiology and Behavior

Martha Constantine-Paton with students in MIT lab
Martha Constantine-Paton working with students in her lab at MIT

If you’ve ever browsed the Wilder Brain Collection in Uris Hall, you may have marveled at how innocuous a human brain seems when it’s just sitting in a jar. How can just three pounds of wrinkly gray matter hold the entirety of a person’s memories, thoughts, and personality? And how does this organ manage to direct learning and behavior? The human brain is the last frontier, continuing to hold secrets that scientists are still trying to discover.

In attempt to uncover at least a few of them, Martha Constantine-Paton, a founding member of the McGovern Institute for Brain Research at MIT and the principal investigator at the Constantine-Paton Lab, has spent her career working with neurons in the brain, trying to determine how these  physical structures translate to behavior. In recognition of her outstanding research, she has been awarded a Guggenheim Fellowship, as well as the Lifetime Achievement Award from the Society for Neuroscience’s Mika Saltpeter.

A normal brain contains about 100 billion neurons, connected to each other in complex networks. As the brain develops through childhood, certain connections that prove useful are reinforced, while others that are less useful are pruned away. The process of a child learning to count to ten or write his name is mirrored in the brain, as the connections between the neurons that control these behaviors become stronger.

Constantine-Paton’s research takes a closer look at these connections and how our knowledge of their workings could lead to a better understanding of learning and development. Her work has focused on the visual systems of animals and a specific class of molecules known as NDMA receptors.

By carefully studying rats that are at a key developmental juncture—in this case, the first time they open their eyes—she has been able to observe the chain of reactions that occur in the brain in response to this dramatic increase in visual information. She has found that NDMA receptors, rather than triggering just a few synaptic connections in response to visual stimuli, actually appear to prime entire systems of synapses for input and subsequent strengthening of connections.

According to another researcher in her lab, Akira Yoshii, this could have far-reaching implications. For example, it could explain how children are able to learn new things quickly. “[Developmental] changes tend to occur suddenly, appearing in short intervals after robust stimulation. It is as if there is a single important trigger and then a functional circuit rapidly comes online.”

Constantine-Paton acknowledges that there is still much we don’t understand. “We haven’t solved the whole puzzle yet,” she admits. “[But] we hope this study might advance the study of normal, healthy brain development so that we may be able to prevent or treat many devastating neurological disorders.” In the case of NDMA receptors, some studies have begun to suggest that improper functioning may lead to schizophrenia and other forms of psychosis. Because of Constantine-Paton’s research, we’re one step closer to understanding—and curing—these diseases.