According to a new study led by UCL researchers, robotic third thumb use can alter brain representation of the hand.
The team trained people to use a robotic extra thumb and found they could effectively carry out dextrous tasks, like building a tower of blocks, with one hand (now with two thumbs). The researchers report in the journal Science Robotics that participants trained to use the thumb also increasingly felt like it was a part of their body.
Before and after the training, the researchers scanned participants’ brains using fMRI, while the participants were moving their fingers individually (they were not wearing the Thumb while in the scanner). The researchers found subtle but significant changes to how the hand that had been augmented with the Third Thumb (but not the other hand) was represented in the brain’s sensorimotor cortex. In our brains, each finger is represented distinctly from the others; among the study participants, the brain activity pattern corresponding to each individual finger became more similar (less distinct).
A week later, some of the participants were scanned again, and the changes in their brain’s hand area had subsided, suggesting the changes might not be long-term, although more research is needed to confirm this.
It wpuld be interesting to see if such a device actually made everyday life easier.