Header Bar Graphic
Astronaut ImageArchives HeaderBoy Image
Spacer

TabHomepage ButtonWhat is NASA Quest ButtonSpacerCalendar of Events ButtonWhat is an Event ButtonHow do I Participate Button
SpacerBios and Journals ButtonSpacerPics, Flicks and Facts ButtonArchived Events ButtonQ and A ButtonNews Button
SpacerEducators and Parents ButtonSpacer
Highlight Graphic
Sitemap ButtonSearch ButtonContact Button

 
Neurolab Online banner

Meet: Charles M. Oman, Ph.D.

Principal Investigator
Roles of Visual Cues in Microgravity Spatial Orientation

photo of charles oman
Photo: MIT News Office
Donna Coveny


What I do:

I'm a research engineer and neuroscientist at the Massachusetts Institute of Technology in Boston. Neurolab is my sixth Spacelab mission. For the past decade I have been Director of the Man Vehicle Laboratory in MIT's Center for Space Research.

Our group studies the physiological and cognitive limitations of humans in aircraft and spacecraft, and tries to develop new ways of improving human-vehicle effectiveness and safety. Some of what we do also has medical applications. We take an interdisciplinary approach, utilizing techniques from manual and supervisory control theory, estimation, signal processing, biomechanics; cognitive, computational and physiological neuroscience; sensory-motor physiology, human factors, and biostatistics.

Many of our students are engineers from the Department of Aeronautics and Astronautics. Some are from other departments, including the Harvard-MIT Division of Health Sciences and Technology, where I have a joint appointment. This year, I've been teaching a seminar on the case for human planetary exploration. I also lead a new multi-investigator neurovestibular research program in the National Space Biomedical Research Institute.

For many years, I've been fascinated by human vision and the inner ear balance system, and wondered why people sometimes experience disorientation and nausea when flying in air- and spacecraft.

My Career Journey

Beginnings
All my life I have been fascinated by airplanes and space travel. Growing up in a New York suburb in the fifties, I built and flew model planes and rockets. I remember back in second grade, crayoning what the interior of a space station should be like instead doing of the assignment. My heroes then were science fiction astronauts Tom Corbett and Captain Video. No humans had actually flown in space yet, but the prospect was exciting. When I watched Sputnik cross the night sky, it somehow seemed obvious that people would follow, and that human destiny included voyaging to the planets and perhaps beyond. Thirty years later, when my students and I look up at the Mir station, many of us still believe our ultimate destiny is pretty obvious.

My thoughts were so much in the sky that I wasn't a good student at first. But in my teens I went to a superb high school in New Jersey called Lawrenceville. I got a broad education from some wonderful teachers, who taught me to connect my dreams with a disciplined life. Both parents understood when I went on to Princeton and decided to major in aerospace engineering. Princeton was an exciting place where I really learned how airplanes and rockets fly. My junior year I got a summer job at the University's flight research hangar. Building esoteric sailwings and hovercraft, I discovered I had a flair for research. I learned to fly real airplanes, and ran the flying club.

I think my scientific interest in the subject of motion sickness probably began back then while learning to fly aerobatics. If motion sickness is caused by motion, how come when my instructor has the controls, I get queasy, but when I do the same loops and spins, I am immune ?

Two Larrys
When I finished Princeton, Apollo was just getting underway, and MIT was designing the guidance system, so I decided to go there for graduate school. Professors Larry Young and Y.T. Li had recently founded the Man Vehicle Laboratory, and Larry gave me a Research Assistantship. My first job was to interface a head tracker to a desktop computer display. It was one of the first interactive virtual reality systems ever built. But the technology was pretty limiting in those days, so I left computer graphics, and took courses in physiology and bioengineering.

Larry was working on the vestibular organs of the inner ear, the accelerometers in the human biological inertial guidance system, and his enthusiasm was infectious. He challenged me to explain the relationship between what was physically happening in the inner ear, and the resulting compensatory eye movements and motion sensations. We used some simple differential equations to model vestibular adaptation. Of course it was an oversimplification, as many models are. People are still struggling to do it properly. But ours explained some previously unexplained things, and became widely used.

Meanwhile, another MIT faculty mentor, Larry Frishkopf , got me interested in how hair cells work in the lateral line organs of aquatic animals. My Doctoral thesis (1972) was on both lateral line and vestibular organs, strongly influenced by both Larrys.

Reverse engineering
I joined the MIT faculty in 1972. Larry Frishkopf and I continued to work together for several years. In my thesis, I had argued that the semicircular canal fluid movement must be far smaller than previously thought. We set out to prove it by studying the inner ear of a big fish, the skate. It was difficult to keep skates in Cambridge, so for several summers in the early seventies, we'd truck our entire lab down to Cape Cod to the Marine Biological Lab in Woods Hole.

Our experiments there required careful microdissection, luck, and sometimes ran all night. Next day we'd give up and go to sleep - or go out sailing. I have been a sailor all my life, and kept a racing dinghy on the beach nearby. Our lab had a superb view of the Vineyard Sound, so sometimes the temptation to get out on the water was overwhelming. Often I'd discover Steve Highstein - now also a Principal Investigator on Neurolab - already there, rigging his boat. Steve had the same problem: a difficult preparation, and a lab with a picture window. Sailing out, we would wave to our more industrious colleagues ashore, but neither of us felt too guilty. Truth be told, in those summers I was away from the lab for days at a time, since I was involved in big boat one design and ocean racing.

I didn't consider it professionally relevant experience at the time, but in a way it was. In storms offshore, I'd wonder how come taking the helm wasn't the instant cure for seasickness as it was when flying. Also it was personally significant: racing on San Francisco Bay in '73, I met my wife Cherry.

Each Fall, we'd move the lab back to Boston, and I'd rejoin MVL. I did some human factors research on recency effects on pilot flying skills, but also kept working on the fluid mechanics of the inner ear, collaborating via P-mail with Ian Curthoys in Australia. Larry Young and I looked for better ways to automate the analysis of eye movements. Johannes Dichgans came to Boston to join us in a study of how moving visual scenes produced illusory self-motion in flight simulators. Otmar Bock - now a Neurolab PI - arrived from Germany for a post-doc, and we decided to study adaptation to left-right vision reversing prism goggles. Otmar and I came to work each morning, and in the name of science made each other motion sick.

    We made the interesting discovery that visually induced self-motion illusion reverses within just a few hours after you don the goggles. We also saw patterns in the time course of nausea development and remission. Pursuing this, I visited Jim Reason at the University of Manchester, who had developed a widely known version of the sensory conflict theory for motion sickness. I recast Jim's theory in mathematical form, and extended it so that it accounted for my pilot/passenger paradoxes, and the time course of symptoms. There were some practical implications for sailors. Seasickness had contributed to the deaths of many yachtsmen in the '79 Fastnet Race gale, so I began writing for sailing magazines, and lecturing on seasickness prevention at Safety-at-Sea seminars.
Astronauts
About that time, astronaut Owen Garriott told us the details of his experience with space sickness on Skylab. The Soviets had been blaming space sickness on fluid shift, but space sickness hadn't been a problem earlier in the small spacecraft used in the US program. Early Cosmonauts had the luxury of big vehicles. It made sense to think that space sickness - like ordinary motion sickness - originated when people were able to get out of their seats, move about, and experience conflicting cues from their eyes, ears, and joints as they moved around. Larry young about to free spin oman during a parabolic flight VCR study

The Shuttle was going to be the biggest spacecraft yet, and we expected sickness would be a problem. So in 1976, Larry Young and I wrote a proposal with our Canadian friends Doug Watt and Ken Money to develop a family of vestibular experiments for the shuttle Spacelab module. Our proposal was accepted, but was six long years till the Spacelab was ready to go.

The delays gave us time to try out our experiments aboard NASA's Vomit Comet parabolic flight airplane. We learned firsthand about visual reorientation illusions, and trained our astronaut subjects to look for them in orbit. When the shuttle began flying in 1981, space sickness suddenly became a well publicized problem. Garry Trudeau's Doonsbury wagged that it should be measured in units called "Garns" - to immortalize Utah Senator Jake Garn, who was honest and admitted he was sick during virtually his entire flight.

Spacelabs
By 1983, Spacelab was ready, and our stuff finally got to go. Over the next decade, we flew on four different missions. Many of the Spacelabs were interdisciplinary, and half the fun was getting to know the other PIs and something about their science. Our crews were terrific, good scientists and fun people. Byron Lichtenberg, one of our students, was selected to fly on Spacelab 1 as America's first Payload Specialist.

Larry Young did a superb job leading the experiment team through three missions. On the fourth, he changed hats, and became Alternate Payload Specialist. Our experiments didn't always turn out as we'd hoped - that's the way it is in science - but we got preliminary answers to several important questions that helped frame the research agenda for this decade.

    We found that gravireceptor thresholds and perception in darkness didn't change as much in orbit as some thought, but that the dominant time constant of the head-eye stabilization reflex did. Crewmembers became more dependent on visual and tactile cues to their self-rotation. Space sickness was triggered by head movements, but the visual reorientation illusions we'd seen in parabolic flight also clearly contributed. There was a simple solution: whenever anyone felt queasy, everyone on board should remain visually upright. After return to Earth, tilting the head created the illusion of moving sideways (due to what we called otolith tilt-translation reinterpretation) and caused earth readaptation sickness.
Rhea Seddon testing Marty Fettman in oman's rotating chair experiment To follow up on the eye movement story, I joined a group developing some more sophisticated rotating chair experiments. The team was ably led by Mill Reschke, and it brought together many experienced university and NASA investigators. It was a simulating and fun group to work with. Our experiments - called the Microgravity Vestibular Investigations, flew in 1992. Some of the Neurolab vestibular team's experiments evolved from results of this mission.

No drug has yet been found which consistently prevents space sickness (or motion sickness on earth, for that matter) so the problem still remains with us. However, giving space sick crewmembers a shot of a conventional antihistamine anti motion sickness drug called promethazine seems to help. The injection is into muscle, so unfortunately it does cause a sore spot.

Neurolab - and the future
To pursue role of vision on orientation in zero-g, I proposed a follow on experiment in the mid eighties using a special slide viewer. This was approved, but indefinitely postponed after the Challenger explosion. However a decade later, NASA began to develop a new virtual reality graphics workstation for the Shuttle and Space Station. It was the ideal research tool for what we wanted to do. With help from Ian Howard and Ted Carpenter-Smith, I revised the proposal and submitted it for Neurolab. Details on what we're up to are available on the Neurolab web site.

MIT graduate student with oman testing a GPS navigation display in the flight simulator Andy Beall joined us for Neurolab, and working through the new National Space Biomedical Research Insitute, we are starting to apply our work to preflight orientation training. With Neurolab colleague Alain Berthoz, we are also developing a new international virtual reality experiment for Space Station.

I have given up flying so I can devote more time to family - like sailing with my kids. But the pilot's role in the aircraft cockpit is changing dramatically, and my interest in cockpit human factors research remains strong. In recent years, I have collaborated with colleagues at DOT's nearby Volpe Research Center to develop concepts for a new generation of vertical navigation and GPS instrument approach displays. But that is a another story.

Likes/Dislikes about career

I consider myself lucky to have been able to combine my passions for aerospace engineering and neuroscience, and make a living at it at a place like MIT, amongst world class students and colleagues. I truly look forward to going to work each day. My wife and two children have been very understanding of my itinerant lifestyle, and more lengthy absences when a mission goes up.

Developing an experiment, trying it in parabolic flight, training a crew, and working with them from Houston during the mission is a fascinating experience. But a career in space life sciences involves professional risk: Each experiment requires years of effort, and sometimes the data you get is disappointing, or the flight is delayed or cancelled. While the space station is under construction, the opportunity to do experiments will be rather limited. It is great to see so many younger people interested in space life sciences, but if you are interested in an academic career, I think you are well advised to get established in mainstream neuroscience or engineering first.

There isn't quite the same excitement about human space exploration now as there was in the early days of the program. NASA suffers from many of the problems of a mature organization. However, I remain optimistic. All this could change as soon as the costs for getting into orbit are lowered, and if interest in the search for the origins of life galvanizes into a human expedition to Mars or Europa. All of us in the game have the satisfaction of working on something we know will be important in the long run.

Advice

When asked:
Several people from your MIT laboratory have become astronauts. You were on the Neurolab Payload Specialist Selection Committee. If a person is interested in becoming an astronaut, what is your advice?

Learn as much as you can about the space program, and find out what an astronaut's job really involves. Astronauts get to do many exciting things, but much of their lives are spent away from home, sitting in technical meetings. And there are the risks of riding the rocket. Get an application form from NASA, and see what the academic, medical and professional experience requirements are. Become a student member of one of the space or professional societies. You can usually find a meeting where you'll have the opportunity to meet some astronauts and talk.

Choose an area of science or technology that truly interests you, and which you think will be important to NASA ten years from now. Become an expert at that. If you're really interested in what you’re doing, working long hours is fun, and you can focus all your energy on being as good as you can be. If you happen not to be selected, you'll have many other attractive career options.

Try to develop an interdisciplinary perspective, and some practical lab and computer skills. Get experience working in several different disciplines and as a member of a team, perhaps at a NASA Center. Of the four or five from our group who have been selected, most of them fit a "T" model pretty well: broad in terms of interests, experience and abilities, but deep in their specialty. And they all have a lively sense of humor.

One last thought: if you make the first cut, but then aren't chosen, be patient and persistent. Believe in yourself. Many astronauts I know have applied several times.


 
Spacer        

Footer Bar Graphic
SpacerSpace IconAerospace IconAstrobiology IconWomen of NASA IconSpacer
Footer Info