Q: How did you become a researcher that studied how people fall?
A: I had done a master’s in biomechanical engineering. The background for this field of research is varied, and I fit on the engineering side. A friend sent me the job ad.
Q: Where did you do this work?
A: It was a research institute at a major hospital. They get funding from larger agencies, governmental grants, that kind of thing.
Q: How many people worked there?
A: The center had about 20 people. About half in research and half in development. I was on the research side. In development, they were doing some product design, mobility aids, like wheelchairs or devices to keep people from falling over, or prevent injury when a fall occurs. But I worked in research.
Q: So what did you do on a daily basis?
A: My title was research coordinator. My duties included recruitment of subjects, data analysis, fitting subjects with the equipment for collecting the data, and running the tests, basically knocking people over.
We were studying ways of preventing falls in older people. We studied the differences between older and younger people falling. For example, their reaction times or how they respond when they fall. We did this by putting them on this floor that accelerates quickly in unpredictable directions.
Q: Was it like a large black floor, kind of like a treadmill?
A: No, it was a floor covered in linoleum tile that had a large metal plate underneath it to measure force.
It’s probably about 8 feet wide by 12 feet long. The floor moves backwards, forwards, left, or right, unpredictably, so that the subject cannot learn to anticipate the perturbations. It’s sort of like the feeling you would get if you were standing on a subway car that abruptly stopped. We’d distract them by telling them to count down by sevens, things like that, so that they wouldn’t be trying to guess when the floor was going to move.
Things are moved in and out of the room depending on the study design—sometimes there are handrails, sometimes there are not. Sometimes there are foam obstacles completely blocking the feet and lower legs so that the only thing you can do to avoid falling is to grab a handrail.
There is a harness suspended from the ceiling in the middle of the room and the rope supporting it is loose when the subject is standing still. It will catch you if you fall, but it still allows you to stumble quite a bit before it supports you. You can’t actually fall flat on your face or anything.
We would also try to determine the difference between an older and younger person paying attention to obstacles in their environment. Sometimes we’d move the obstacles by their feet.
Or sometimes they would put goggles on that became opaque as soon as the floor moved. These sorts of things provide a measure of what visual information is used to restore balance—how much subjects pay attention to their environment before the floor moves, etc.
Q: This job is unbelievable.
A: I know. I used to tell people at parties that I knock people over for a living and no one believed me. Every now and then, after a team meeting, I would be struck by how absurd it was that we’d just spent 30 minutes in a brainstorming session on new or better ways to make people fall down.
Q: Did you ever try it?
A: I had to do one or two sessions. It’s mostly just tiring. I’m not really a thrill-seeking person, though, and I don’t enjoy having the floor moved. I was nervous every time.
Q: How many tests do they do?
A: They do about 120 perturbations per session.
Q: Are they fast?
A: The perturbations? Generally, yes, though some are faster than others. But the overall testing sessions are quite lengthy. It takes about five hours from start to finish. Not all that time is spent on the platform—they have to do a prescreening test and be fitted with all the various equipment: the sensors, the harness.
Q: How long did you work there?
A: One year.
Q: Did you ever learn anything useful?
A: I was assisting with a whole bunch of different studies, and a year isn’t enough time to get enough data to really apply it to anything. But there were reams of data collected in that time. I just didn’t stick around long enough to get the big picture.
Q: So you recruited people for the studies? How did you do that?
A: Recruiting was pretty passive. The younger people we got through word of mouth. We’d bring in our friends or get students from a nearby college.
The older people were mostly through traffic in the hospital. A lot of the older people simply wanted to contribute to the scientific knowledge base. We couldn’t take anyone with a history of falling.
My mom did it once, but we had to send her home because she couldn’t complete the study. There’s an eye-tracking device that’s attached to what looks like the inside of a hardhat. A little camera lines up with the subject’s eye so you can see where they’re looking. My mom’s head was too small for the device, so we sent her home after two hours.
Q: Was she relieved?
A: I think so. She wasn’t keen on coming in the first place, and jokes that it was just an example of how much she loves me.
Q: How much were people paid?
A: I think it was $10 per hour. We also paid their parking at the hospital and provided snacks during the testing sessions.
Q: Do you think we will ever be able to prevent older people from falling?
A: The group has already made some progress in fall prevention, but it will never be possible to prevent people from falling altogether.
There’s lots of hope for the future, though. Falls in elderly people are a serious problem, and falls and fall-related complications account for a high proportion of deaths in elderly people, so it’s an important issue to tackle.