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Stable cortical body maps before and after arm amputation - Nature Neuroscience

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Reposted by Hunter Schone

Nature Neuroscience @natneuro.nature.com · Sep 3

Longitudinal neuroimaging in three adults, followed before and up to 5 years after arm amputation, reveals that amputation does not trigger large-scale cortical reorganization

@hunterschone.bsky.social @cibaker.bsky.social @plasticity-lab.bsky.social

www.nature.com/articles/s41...

Longitudinal neuroimaging of participants with planned arm amputations shows that the cortical body map remains stable after amputation, with no evidence of hand or face reorganization, thus challengi...

After an amputation, the brain’s map of the body is more stable than previously thought

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Reposted by Hunter Schone

Science Magazine @science.org · Aug 28

Phantom feelings in lost limbs present a puzzle for neuroscientists who were taught to believe that once a body part is amputated, another body part will creep into its spot on the brain’s map of the body.

A new imaging study undermines that theory. https://scim.ag/45SInZQ

Imaging study could inform future prosthetics and treatments for phantom limb pain

scim.ag

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Reposted by Hunter Schone

Vishal Rawji @vishrawji.bsky.social · Jul 18

Preprint out -- using intramuscular microelectrode arrays to detect residual motoneuron activity in tetraplegic spinal cord injury, and then using that activity for control
Credit to my other co-first authors Agnese Grison and Ciara Gibbs
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www.medrxiv.org/content/10.1...

Multidimensional motoneuron control using intramuscular microelectrode arrays in tetraplegic spinal cord injury

Loss of hand function after spinal cord injury (SCI) significantly impairs independence and quality of life. Although residual muscle activity recorded on the skin can provide intuitive control signal...

www.medrxiv.org

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Reposted by Hunter Schone

Marieke van Vugt @mvugt.bsky.social · Aug 22

"primary somatosensory cortex stays remarkably constant even years after arm amputation. The study refutes foundational knowledge in the field of neuroscience that losing a limb results in a drastic reorganization of this region, the authors say." www.nature.com/articles/d41...

The brain’s map of the body is surprisingly stable — even after a limb is lost

Study challenges the textbook idea that the brain region that processes body sensations reorganizes itself after limb amputation.

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Hunter Schone @hunterschone.bsky.social · Aug 22

Thanks for the interest!

Dave is right that there are many studies that have mapped the phantom hand post-amputation.

However, the real novelty is ours is the first to offer data mapping the hand and lips before AND after amputation, offering a direct comparison between the maps before vs. after

Stable cortical body maps before and after arm amputation - Nature Neuroscience

Reposted by Hunter Schone

Jeremy Hogeveen @jeremyhogeveen.bsky.social · Aug 21

Of course I stumble onto this paper right before I head to discuss post-injury remapping in my cog neuro lecture this morning www.nature.com/articles/s41... 🙃

Longitudinal neuroimaging of participants with planned arm amputations shows that the cortical body map remains stable after amputation, with no evidence of hand or face reorganization, thus challengi...

The brain’s map of the body is surprisingly stable — even after a limb is lost

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Reposted by Hunter Schone

Brokoslaw Laschowski @drlaschowski.bsky.social · Aug 22

Well, neuroplasticity — you had a good run.

Nature @nature.com · Aug 21

A brain-imaging study of people with amputated arms has upended a long-standing belief

go.nature.com/3Jp9NPG

Study challenges the textbook idea that the brain region that processes body sensations reorganizes itself after limb amputation.

go.nature.com

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Hunter Schone @hunterschone.bsky.social · Aug 22

Our longitudinal data confirms the maps are preserved. IMO, we need to stop chasing cortex and redirect our efforts to the periphery — the state of the nerve post-amputation, how to best reinnervate the nerve during surgery, the more likely driver of phantom pain

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jnnp.bmj.com/content/93/8...

Making sense of phantom limb pain

Phantom limb pain (PLP) impacts the majority of individuals who undergo limb amputation. The PLP experience is highly heterogenous in its quality, intensity, frequency and severity. This heterogeneity...

jnnp.bmj.com

Hunter Schone @hunterschone.bsky.social · Aug 22

The issue: clinical trial after clinical trial shows these therapies perform no better than placebos. Yet, these remain front-line treatments for phantom limb pain — essentially snake oil IMO sold under a neuroscience rationale that doesn’t hold up.

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Hunter Schone @hunterschone.bsky.social · Aug 22

You’re right—phantom limbs have always suggested the brain’s body map isn’t erased. The problem is the field went all-in on the idea that amputation causes reorganization. This has fueled decades of therapies (mirror box, VR, sensory discr. training) trying to “fix”supposedly broken brain maps

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Reposted by Hunter Schone

Maggie Szymanska @maggieszymanska.bsky.social · Aug 22

Really delighted to announce that our paper is now out! We fMRI scanned patients both before amputation and after - allowing us to make direct comparisons.

We found that the cortical maps are extremely stable, almost unchanged - even 5 years after amputation!

Hunter Schone @hunterschone.bsky.social · Aug 21

Now out in @natneuro.nature.com

What happens to the brain’s body map when a body-part is removed?

Scanning patients before and up to 5 yrs after arm amputation, we discovered the brain’s body map is strikingly preserved despite amputation

www.nature.com/articles/s41593-025-02037-7

🧵1/18

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Hunter Schone @hunterschone.bsky.social · Aug 21

Worth checking out: www.sciencedirect.com/science/arti...

They show that, irrespective of amputation, people (amputees and non-amputees) will report referred sensations at similar rates, by shaping their expectations. In other words, these effects are based on a suggestion bias, not remapping.

Hunter Schone @hunterschone.bsky.social · Aug 21

I don’t think phantom pain is at all associated with cortical body maps. I think the older studies put the entire phantom pain clinical field on a wild goose chase to fix broken body maps

I think we need to focus more on the peripheral nerve state post-amputation, ie procedures like TMR and RPNIs

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Hunter Schone @hunterschone.bsky.social · Aug 21

We can only access the persistent ‘winner’ in humans because we can ask them to move their phantom fingers

We can perform this winner-takes-all analysis to replicate this supposed remapping, if we ignore the missing hand (red) and assign the territory to the next winner: lips (blue) or feet (green)

Hunter Schone @hunterschone.bsky.social · Aug 21

This does not mean that the monkeys’ brains forged new connections or that neurons changed their tuning because of the amputation, just that the region was already residually responsive to the adjacent fingers. You’re simply unmasking the adjacent digits, which you now assign to that territory.

Hunter Schone @hunterschone.bsky.social · Aug 21

They then assigned each cortical territory to the finger that elicited the greatest neuronal response when it was being touched, but because they could not touch the missing finger, the missing digit cannot be assigned any territory, because you can’t physically touch it.

Adult human cortex does not reorganize after amputation

Hunter Schone @hunterschone.bsky.social · Aug 21

Glad you found it interesting. Happy to explain! In the 1980s monkey experiments, researchers identified the animals’ somatosensory maps by recording from neurons, while simultaneously touching the animal’s remaining fingers with a glass probe after performing an amputation of a single finger

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Reposted by Hunter Schone

University of Cambridge @cam.ac.uk · Aug 21

Contrary to what many neuroscientists think: the brain holds a map of the body that remains unchanged even after a limb has been amputated: https://bit.ly/3UyFkRx

@mrccbu.bsky.social‬ ‪@pittdeptofmed.bsky.social ‪@plasticity-lab.bsky.social‬ ‪@hunterschone.bsky.social 🧪 #PhantomLimb #Research

Two images of the same person side by side. On the left, the person is seated at a table, about to gift-wrap a small box. On the table is a roll of wrapping paper, the box and a pair of scissors. They are handling a sticky tape dispenser with two arms. On the right, the same individual, in the same set-up but now their left arm is missing.

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Reposted by Hunter Schone

The Transmitter @thetransmitter.bsky.social · Aug 21

“This neural configuration before amputation remains after the amputation. And it’s not ‘use it or lose it,’” says John W. Krakauer.

By @avaskham.bsky.social

#neuroskyence

www.thetransmitter.org/plasticity/a...

The results from a new longitudinal study contradict classic findings in monkeys but may not warrant a rewriting of the textbooks just yet.

www.thetransmitter.org

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Reposted by Hunter Schone

Neuroengineering @neuroengineering.bsky.social · Aug 21

Hunter Schone @hunterschone.bsky.social · Aug 21

Now out in @natneuro.nature.com

What happens to the brain’s body map when a body-part is removed?

Scanning patients before and up to 5 yrs after arm amputation, we discovered the brain’s body map is strikingly preserved despite amputation

www.nature.com/articles/s41593-025-02037-7

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Hunter Schone @hunterschone.bsky.social · Aug 21

Not to be a super fan. But, I talk about your study all the time. Beautiful work!