Our brain has specific areas for each finger. But what happens to those who need to cope without them?
By Rafael Battaglia
Sep 27, 2019, 7:57 pm
We use our hands for almost everything. Just pause for a moment and think about how dependent we are on them every day: to brush our teeth, drive, cook, play sports, and even choose that WhatsApp sticker.
Because of this, each of our fingers has a corresponding region in the brain. This superspecific brain mapping makes controlling all articulated bits of the hand much more precise.
But what happens to those who don't have these members? One study showed that in people who need to use their feet for daily tasks, such as brushing their teeth (and even painting in the case of artists), their toes eventually replace their toes, occupying the same brain area.
This is the first time this behavior has been observed in humans. Because most people don't use their toes for complex activities, the brain doesn't feel the need to map them. This is not the case, for example, with other primate species, which use their feet all the time to climb and hold objects and food.
Changing feet for hands (or the other way around)
The research was done by University College London, UK, and published in the journal Cell Reports. For the study, scientists analyzed the sensory responses of two British artists who use their feet to paint (and who do not have upper limbs), and 21 people who use their hands to serve as a control group.
To observe brain behavior, participants underwent an MRI. During the exam, the researchers tapped each other's feet and observed how these stimuli were interpreted.
The results showed that, in the artists, there was a complex brain map with regions for each toe – regions that, in other participants' brains, were intended for the fingers.
This was the result of a lot of training, of course, as you have to develop the sensory perception of each toe individually. Even in the case of painters, the perception of the right foot was greater than that of the left. The explanation is simple: in the artists' daily lives, who are right-handed, the left foot is used more for stabilization – a far less complex activity than painting a canvas.
Research like this shows how our brain has the ability to shape and adapt as we use it in different ways.
"The maps we have in our brains aren't necessarily fixed," he said in a statement. announcement Tamar Makin, study leader. “They seem to be that way just because most people behave very similarly.” Exploring this brain plasticity can help improve rehabilitation or amputated limb pain treatments, for example.
According to research, artists who volunteer are not in the habit of wearing closed shoes. It makes sense, after all, they use their feet often. Scientists believe this custom may have helped to develop the most complex sensory perception in this part of the body.