When the experimenters become the experiment
Some scientists get deeply, personally involved in their research, whether by zapping their muscles as they sleep, using lasers on their eyes or offering an arm to hungry mosquitoes
A group at UCD’s school of physics uses low-power lasers to build up images of the living retina to better understand how light coming in from different angles is picked up. Image: Getty
Aedes aegypti: a vector for dengue fever and yellow fever
The history of science is strewn with stories of self-experimentation. It’s not something to try at home, but in some cases the inquisitive researchers not only lived to tell the tale but also made a major discovery or advance.
In the 1980s, Australian Barry Marshall drank a soup of bacteria to show that Helicobacter pylori causes peptic ulcers and scooped a Nobel prize as well as a belly ache for the discovery.
JBS Haldane also suffered for the cause – in the 1940s he spent time in a decompression chamber to look at how gases affect the human body. As well as gathering results, he also got a burst eardrum and seizures for his trouble.
It is not uncommon for scientists to involve themselves in their experiments to this day, but regulations and ethics committees are there to put the brakes on the more extreme notions. So why do scientists self-experiment? And what are they finding out?
For Dr André Brodkorb, getting to grips with how a milk protein called alpha- lactalbumin gets digested in the stomach meant putting his own stomach on the line. “We had done some trials in test tubes in the lab, and I was excited about the prospect of a human study, which we did at the Mercy University Hospital in Cork,” recalls Brodkorb, who is a research officer at Teagasc, Moorepark.
“And when it came to recruitment I had to show leadership for my students. We had 10 people taking part and all of a sudden I was one of the dots on the graph.”
For the trial he had a nasogastric tube inserted into his stomach, then he drank the protein drink and samples were pulled out through the tube over time. It was a not wholly pleasant experience, he recalls.
As he waited for his stomach to do the digesting, out of interest the gastroenterologist showed him a tiny gadget for a “capsule” endoscopy, which takes real-time images of the gut as it passes through.
“So we had this idea to use it to watch as the proteins are digested in the stomach,” he says.
Again, Brodkorb was the guinea pig. This time a pH probe was fed down into his stomach and he swallowed the protein drink and the camera.
“We saw how the protein coagulated and how that correlated with the acid secretion in the stomach,” he says. “It clearly showed the difference between what happened in the test tube and in the stomach.”
Those insights have sparked interest from colleagues across Europe and also from industry, says Brodkorb, who now shows his “gut movie” to researchers and companies.
For Prof Brian Caulfield, trying new approaches out on himself is part and parcel of being a physiotherapist.
“Our place of work is the human body, and we use physical means and exercise to rehabilitate people,” he says. “So it’s somewhat natural to test things on ourselves.”
Caulfield, dean of physiotherapy at University College Dublin and a director at the new Insight Centre for Data Analytics, is interested in finding ways to enhance human performance in health or in sport.
A few years ago he wanted to find out if electrical stimulation could get muscles to burn off large numbers of calories during rest. So he rigged himself up to zap his leg muscles as he slept.
It went well, but before we get too excited about the prospect of getting a workout as we snooze (Caulfield doesn’t see that as a runner right now), he sees more practical applications.
“It has the potential to help maintain some level of cardiovascular fitness while a person is on imposed long-term bed rest or in other scenarios where people cannot do exercise themselves,” he says.
Caulfield and his students also try out other experimental protocols on themselves, such as tracking the motion of joints and limbs when worked to fatigue. He has even had saline injected into his knee to mimic swelling after injury so the joint motion could be measured.
But more generally, it helps when working with volunteers if you have been through the experience yourself, he notes. “It is not absolutely necessary, but there’s a certain level of credibility when you ask someone to do something and you have already done it yourself.”
Can you see it now?
Another advantage to the DIY approach is that you are not relying on someone else’s report of what they are experiencing during the experiment, according to Dr Brian Vohnsen of the advanced optical imaging group in UCD’s school of physics.
The group uses low-power lasers to build up images of the living retina, the light- sensitive tissue at the back of the eye, and carry out experiments to better understand how light coming in from different angles is picked up. The researchers use their own eyes as subjects, he explains, noting that the lasers are well within safety limits and that he and his colleagues have eye checks.
The aim is to develop techniques to detect early signs of disease and possibly even improve artificial lenses, and self- experimentation is a good place to start, according to Vohnsen.
“You can see things with your own eyes, rather than asking someone else what they see,” he says.
MOSQUITO MEAL: CUTTING-EDGE RESEARCH
If you have ever spent time covering up, swatting or dousing yourself in repellant to keep mosquitoes at bay, you might wonder why anyone would offer themselves up willingly as a meal for them. But for Prof Leslie Vosshall, it’s a practical option.
She and her group at the Rockefeller University study the genetics and behaviour of Aedes aegypti, which is a vector for dengue fever and yellow fever. For the female insects to produce eggs they need a blood meal, and this is where Vosshall rolls up her sleeve.
“We get the most efficient blood-feeding if we just use our arms,” she explains.
Already the group is discovering more about how insect “smell receptors” help mosquitoes to discriminate humans from non-humans and to be repelled by the chemical Deet, and the researchers are also looking at the role of carbon dioxide in mosquito-host attraction.
The lab’s work with the mosquitoes is “strictly regulated”, according to Vosshall, who is happy to offer her arm to the insects, although she now knows to cover up her hand.
“I [initially] made the mistake of putting my whole arm in there and got a lot of bites between my fingers, which were incredibly itchy,” she recalls.
“Since then, I always protect my hand with a glove, to limit the biting to my forearm. These days the itching goes away in an hour or so.”