Seeking biology that underlies behavior

Several hundred participants were treated to a view of the marvels of modern neuroscience Nov. 30, thanks to the marvels of modern communications technology during a New York conference telecast to audiences in Chicago and Boston.

The conference featured three prominent Harvard faculty whose research focuses on the brain: Carla Schatz, Nathan Pusey Professor of Neurobiology and head of Harvard Medical School’s Neurobiology Department; Joshua Sanes, professor of molecular and cellular biology and Paul J. Finnegan Family Director of the Center for Brain Science; and Steven Pinker, Johnstone Family Professor of Psychology.

The faculty panelists discussed recent research on how the brain and nervous system operate, as well as the link between individual differences in personality and thinking, and the physical structure of the brain.

Harvard President Lawrence H. Summers introduced the panel, which was moderated by Provost Steven E. Hyman. The event, “Building Connections: Exploring the Mind and Brain,” was sponsored by the Harvard Alumni Association. “Building Connections” took place at the Harvard Club of New York City and was broadcast via satellite to Hawes Hall at Harvard Business School, hosted by Associate Professor of Neurobiology Richard Born, and to a third location in Chicago, hosted by Harvard Medical School Dean Joseph Martin.

Summers set the tone for the evening’s discussion by highlighting the rapid progress made in recent decades. Neurobiology is a relatively young discipline, with the first neurobiology department being established at Harvard Medical School in 1966.

“We couldn’t have done this [conference] five years ago, and much else couldn’t have been done 25 years ago, including almost everything we’re going to talk about today,” Summers said.

Summers said that Harvard has an opportunity today to answer some of the basic questions in neurobiology. Those include how the brain works, the biological foundations of human behavior, and new knowledge about diseases such as depression, which affects millions of people worldwide.

“Of all the questions that can be asked, few are more fundamental than how it is that a bunch of chemical reactions make you feel you are you,” Summers said. “Those were not questions amenable to scientific inquiry 20 years ago. They are questions that are amenable to scientific inquiry today.”

Summers said advances in technology and tools in recent years have been important factors in new discoveries. While traditional investigation and scientific inquiry are critical, Summers said new microscopes, imaging technology, and other types of tools are providing scientists with ways to see, test, and understand things they were unable to before.

Pinker described using a new functional magnetic resonance imaging (MRI) machine to see the parts of the brain involved in language processing. Pinker said we take our use of language for granted, but how we process sounds to words and thoughts is extremely complex.

“Language comes so naturally to us that we often don’t understand how miraculous language is,” Pinker said. “You’re sitting in chairs listening to five people making noises as they exhale.”

Pinker showed experiments where people mentally changed verbs to past tense by adding ” – ed” while in the MRI machine. By comparing the images with those of subjects who simply thought the same word twice, without changing the ending, Pinker was able to pinpoint a part of the brain used in that specific part of language processing, advancing our understanding.

Schatz said recent research has shed light on how individuals can vary so much, when we’re all drawn from the same genetic blueprints. Research on the connections between the eye and the brain has shown that individual experience and varying physical conditions affect how the brain is wired.

Sanes said that recent advances that incorporate a fluorescent protein into laboratory mice allow researchers to watch a single nerve cell grow, compete with other nerve cells, and contact a target cell, in this case a muscle cell.

Using similar techniques, Sanes said researchers at the Center for Brain Science are hoping to understand the brain’s circuitry, made up of “millions of neurons, trillions of connections” and which he described as similar to tracing the circuitry of a pot of spaghetti.

“We hope we can finally trace out the wiring diagram of the brain,” Sanes said.