powered by:
valneva canada inc.
using feet may reshape the brain
sensory maps promise to improve the lives of people without limbs and those recovering from a stroke.
feb 4 2020
3 minute read
getty images
tom yendell is known for more than just his beautiful paintings of landscapes. having been born without arms, his talent for painting also lies in how he paints — with his feet.
while remarkable on its own, yendell’s talent for painting with his feet has neuroscientists excited to get a unique look into understanding how the brain can adapt to different physical experiences.
“it was through meeting and observing [yendell] doing his amazing painting that we were really inspired to think about what that would do to there brain,” said harriet dempsey-jones, a postdoctoral researcher at the university college london (ucl) plasticity lab, in an interview with smithsonian magazine.
the lab, run by tamar makin, is devoted to studying the sensory maps in the brain.
smithsonian magazine says that sensory maps assign brain space to process motion and register sensations from different parts of the body. these maps can be thought of as a projection of the body onto the brain. for example, the areas dedicated to the arms is next to the areas dedicated to shoulders.
makin’s team at the plasticity lab specifically study the sensory maps that represents the hands and feet. in artists who use their hands, the brain region dedicated to the hands has discrete areas for each of the fingers. but unlike these defined finger areas, individual toes lack corresponding distinctive areas in the brain. the sensory map for feet looks more like a blob.
advertisement
advertisement
dempsey-jones and her colleagues wondered whether the sensory maps of ‘foot artists’ would be different from the sensory maps of ‘handed’ people. she brought yendell and another foot artist named peter longstaff into the lab to interview and assess their ability to use their feet with tools designed for the hands.
researchers used an imaging technique called functional magnetic resonance imaging (known as fmri) to take a picture of the sensory functions inside the artists’ brains. they stimulated the artists’ toes by touching them one at a time to see which specific parts of the brain responded to the stimuli. scientists found that distinct areas lit up as they stimulated each toe, and saw there were highly defined areas of the brain dedicated to each of the five toes. these areas don’t seem to exist in handed people.
scientists have always known that the brain is malleable, and that with training and experience that the fine details of sensory maps can change. these maps can be fine-tuned and even reshaped. however, scientists have never observed new maps appearing in the brain.
these findings are important for the new technology field of brain-computer interfaces (bcis), which can translate brain activity into electrical commands that control computers. this new technology is aimed to improve the lives of people without limbs or for those recovering from a stroke, so understanding the fine details of how the body is represented in the brain is critical for the development of brain-computer technologies.
advertisement
advertisement
“if you want to have a robotic limb that moves individual digits, it’s very useful to know that you have individual digits represented, specifically in the brain,” dempsey-jones said.
there are still many questions about how these toe maps arise and whether they are learned or presented at birth. dempsey-jones believes it could be a genetic predisposition for an organization map, but that you need sensory input from a particular time of life to support and fine-tune it.
she and her team may be able to determine through childhood experiences which time points are necessary for new developments in the sensory brain map of the brain. when scientists are able to determine the period of development for toe maps, they hope it can improve their understanding of the brain and lead to improving technologies for people with missing limbs.
share story
