Researchers at University College London, in the UK, have discovered that the brains of artists who paint with their feet have specialized areas linked to each individual toe. That makes them different from most of us, whose brains only show this level of detail for our fingers.
An artist drawing with his feet. Scientists have discovered that, unlike most people, foot painters ... [+]
Every single finger you move is linked to a particular area in your brain. That specialization is linked to your ability to carry out very fine and detailed movements, so it probably comes as no surprise that the same is not true for your toes. As far as your brain is concerned, there isn’t much difference between your middle toe and your pinky toe and any of the other ones.
On the other hand — or rather, foot — primates who regularly use their feet do have a “toe map” in their brain. That’s been found in macaques, for example. When you touch any of their individual monkey toes, a very specific region of their brain is activated.
So would people who regularly use their toes for detailed and specific tasks have a toe map in their brains just like other foot-using primates have? That’s what the UCL research team, led by Tamar Makin, wanted to find out.
They scanned the brains of two of the UK’s foot painters, Tom Yendell and Peter Longstaff. Both are talented artists who have been painting with their feet for decades. To them, opening a tube of paint or gripping a paintbrush is as easy to do with their toes as it is for us to do with our fingers, and their foot painting skills are far superior than what most of us can achieve with a brush in our hands.
When Makin’s team used fMRI to look at the painters’ brains, they noticed that they both displayed the same kind of toe maps as other foot-using primates of the non-human kind do. Each individual toe was linked to a specific region of the brain, whereas for non-footpainting controls, toe activation was scattered throughout a much larger area.
The big question is whether toe painters have developed this phenomenon through regular use of their feet, or whether all humans are born with toe maps that disappear as we age. Could you create your own brain toe map if you use your feet more?
That’s difficult to say, partly because the two artists involved in the study don’t just use their feet for painting. They have been using their feet for everything their entire lives. Both Yendell and Longstaff were born without arms after their mothers took thalidomide during pregnancy.
For a few short years in the late fifties and early sixties, thalidomide was prescribed as a sleeping aid to pregnant women. When more than ten thousand children across the world were born with deformities, thalidomide was quickly taken off the market, but there are still thousands of adults with physical disabilities as a result of this drug. Many of them, like the two artists, are so used to not having the same set of four functional limbs that most people are born with, they have completely adapted to live and work without them.
To better understand the full extent of how much the brain can learn to create new maps for toes and fingers, future research needs to include a larger group of people with different histories of using their feet and hands. Ultimately, understanding how the brain assigns specialties to individual fingers and toes could help researchers develop new kinds of prosthetics with more detailed control.
