New research challenges existing ideas about brain reorganisation following amputations, and helps explain amputees’ sensory experiences.
22 August 2025
By Emma Barratt
For a long time, scientists have believed that the brain reorganises itself when we lose a limb, repurposing regions that allowed us to sense and move the amputated body part. Some work involving macaques with damage to the nerves in their arm, for example, provided seemingly solid evidence for this; researchers observed that regions of their brain usually reserved for arm-related sensation would only respond to sensations on the face some time after their injury.
Now, a team of scientists has conducted research with humans to check whether this long-standing theory is true. In their new publication in Nature Neuroscience, Hunter Schone and colleagues report that cortical representations of lost limbs actually remain remarkably stable, even years after the initial amputation. Not only does this investigation seemingly upend a long-held belief across cognitive disciplines, but it could lead to new targets for interventions treating phantom pain, and offer new possibilities for developers of next-generation prosthetics.
The starting gun for this study came from amputees sharing their day-to-day experiences of the kinds of sensations and perceptions associated with their amputated limb. As the authors shared in an interview about the study with Nature, amputees would often say that they could 'still feel the limb', and had the sensation of moving parts of it, even years on from when it was removed.
This planted seeds of doubt within the research team. Textbook theories stipulated that parts of the brain associated with those sorts of experiences should have been at least somewhat 'overtaken' to handle different functions from neighbouring brain areas, now that they were no longer responsible for an absent body part. This consistent flow of reports suggested, though, suggested the contrary: perhaps this process wasn't happening after all.
So, the team decided to put their curiosity to the test, recruiting three individuals who had been scheduled for arm amputations in the near future. By asking these participants to perform a series of movements in an fMRI scanner (such as tapping their fingers, moving their toes, and pursing their lips), the researchers were able to pinpoint specific regions of each of their brains that sensed their hands, as well as adjacent areas that processed sensations and movement from other body parts.
These scans and motions (now performed with phantom fingers) were repeated up to five years post-amputation, in order to collect data on how these parts of the brain were changing with the loss of the limb. If established theories held true, the team would have expected to see evidence of encroachment from neighbouring areas on lost-limb associated regions. This might have looked like activation in the hand region while the participant pursed their lips, for example.
Instead, they saw something quite different. Even as far out as five years post-amputation, their bodily representations within the brain were highly comparable to those pre-surgery. In other words, the areas associated with the amputated limb had not been reorganised or encroached on by nearby areas that handle other parts of the body. Counter to existing theory and widely-held assumptions, they remained intact.
Replication of these findings is an important step that's yet to be completed. But, if they are replicated, this not only marks a shift in our understanding of how the brain handles amputation, but could provide the basis for new therapeutic approaches. This could include new options for treating phantom pain, as well as further possibilities for advanced prosthetic devices that make use of brain–computer interfaces.
Read the paper in full:
Schone, H. R., Maimon-Mor, R. O., Kollamkulam, M., Szymanska, Malgorzata A, Gerrand, C., Woollard, A., Kang, N. V., Baker, C. I., & Makin, T. R. (2025). Stable cortical body maps before and after arm amputation. Nature Neuroscience, 1–7. https://doi.org/10.1038/s41593-025-02037-7
SOURCE:
https://www.bps.org.uk/research-digest/amputation-doesnt-change-our-brains-body-map-after-all(accessed 25.08.25)
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