April 9, 1999

Space one of many new frontiers in brain research

Space one of many new frontiers in brain research



A child in the crowd asked Taylor Wang, Ph.D., Centennial Professor of Materials Science and Applied Physics, what it feels like to blast off from earth.

"The first couple of minutes are like riding in the back of a jeep on a very bumpy road. Then it feels like someone really heavy is sitting on your chest," answered Wang, who participated in a NASA space shuttle mission in 1985.

Wang talked about conducting science experiments in space as part of "Brains in Space," one of many 1999 Brain Awareness programs, sponsored last month by Vanderbilt's Center for Molecular Neuroscience. Brain Awareness is a national program that aims to educate the general public about how the brain works and the importance of brain research.

This year's series of programs and activities here in Nashville was a rousing success, organizers said.

"We had great participation in all of our programs, and the people who attended were enthusiastic about the speakers, the content, and the fact that Vanderbilt was providing these free educational opportunities," said Marcie Pospichal, Ph.D., assistant director for programs for the Center for Molecular Neuroscience. "Seeing people benefit from Vanderbilt's research, patient care, and outreach endeavors has been profoundly rewarding."

Sudekum Planetarium at the Cumberland Science Museum served as the perfect setting for the "Brains in Space" program. The audience enjoyed a planetarium show followed by presentations about designing and conducting space shuttle experiments.

Last April, NASA launched the Neurolab mission aboard the space shuttle Columbia.

"Neurolab was the most important mission ever for medical science," said Dr. David Robertson, professor of Medicine and director of the Clinical Research Center as well as the Center for Space Physiology and Medicine. "Twenty-six projects were selected from 180 proposals submitted from all over the world, and Vanderbilt had a project on this mission."

The Vanderbilt Neurolab project was developed by Robertson; Dr. Italo Biaggioni, associate professor of Medicine and Pharmacology; Dr. F. Andrew Gaffney, professor of Medicine; and Andrew Ertl, Ph.D., assistant professor of Medicine, to study the problem of orthostatic intolerance.

Many astronauts, on returning to earth, suffer a decreased ability to remain in a standing position. They experience light-headedness, nausea, dizziness, and high heart rates. About half a million people in the United States suffer from these extended "head rushes," also described as postural orthostatic tachycardia syndrome, or mitral valve porlapse.

Robertson's group studies how the nervous system and cardiovascular system interact to control blood pressure, and they are interested in what goes wrong for individuals suffering from orthostatic intolerance.

"The microgravity of space flight is a good model for orthostatic intolerance," Ertl said. "Astronauts develop the problem and return to normal in about five days. We are interested in how the communication between the nervous system and the cardiovascular system adapts to space flight."

The Vanderbilt team directly measures nerve signals traveling from the brain to blood vessels using a technique called microneurography. An electrode – a wire just bigger than a human hair – is placed in a nerve under the skin behind the knee to detect nerve activity. Specially developed equipment amplifies the signal from the electrode.

Prior to last year's Neurolab mission, the astronaut payload specialists learned how to implant the electrode and take the recordings at Vanderbilt University Medical Center. Two hundred volunteers served as subjects for the astronauts.

"After developing new equipment and training the astronauts, we could only wait and see," Ertl said. "You can't tell if the experiment will work until it's in space."

Wang echoed this sentiment. He was responsible for conducting 14 experiments, including one of his own, during his space shuttle mission.

"I had planned the experiment five years earlier, spent two and a half years training, and when I flipped the switch to turn on the experiment, nothing happened," Wang said. "NASA wanted me to abandon it and finish the other experiments, but fortunately I repaired it and got the experiment going."

Vanderbilt's Neurolab experiments were a success. Ertl showed the crowd a recording of the first microneurography conducted in space. The researchers found that the nervous system still communicates with the blood vessels in space; in fact, activity is a little higher.

"People said it couldn't be done and it wouldn't work. It did," Ertl said.

"This is a good model for orthostatic intolerance," Robertson said. "If we can develop treatments to keep astronauts from passing out on their return to earth, we can use the same strategies to treat the half million people who suffer from this problem."

Conducting science in space is important, Wang said.

"Science is about looking for the clues nature provides. The environment of space gives us whole new sets of clues."