In partnership with
PHANTOM LIMB PAIN IS TIED TO NERVE AND BRAIN CHANGES
How Can Someone Feel Pain In A Limb That Is No Longer There?
After Decades Of Study The Cause Is Still Not Fully Understood
Researchers Have Tied The Pain To Changes In The Nerves And The Brain
Finding A Treatment That Works Is Also Difficult
Some Patients Get Relief And Others Do Not
Researchers Say Knowing The Cause May Help Explain That Difference
THIS NEWSLETTER IS FOR INFORMATIONAL PURPOSES ONLY. NOTHING IN THIS CONTENT CONSTITUTES MEDICAL, PSYCHOLOGICAL, OR PROFESSIONAL ADVICE. ALWAYS CONSULT A QUALIFIED HEALTHCARE PROFESSIONAL BEFORE MAKING ANY HEALTH RELATED DECISIONS.
A Quick Shoutout To Our Sponsor: CBDISTILLERY
Here's What They Have For You 🍃
👇🏻
The CBD Brand that Actually Does What It Says
CBD is having a moment and CBD brands are everywhere right now. But with so many options, it can be tough to know what to look for – and which brands actually follow through on their claims.
That’s where CBDistillery sets itself apart. For the past decade, all of CBDistillery's products have been made with non-GMO, US-grown industrial hemp and with 100% clean ingredients – no corn syrup or artificial colors, flavors, preservatives or sweeteners.
They frequently introduce new and innovative products formulated to meet a variety of wellness needs and customer preferences. And every single batch of CBDistillery’s gummies, oil tinctures, topicals and softgels are tested by an independent, accredited lab to make sure what’s in the package matches what’s on the label.
Right now, CBDistillery is offering our readers a special deal: save 50% on orders of $75 or more with code NEWS50!
OKAY BACK FROM THE NEUROLOGY LAB 🧠
👇🏻
A WOMAN WHO FEELS A HAND SHE NEVER HAD 🖐️
Researchers In London Studied The Case Of One Woman
She Was 38 Years Old And Had Been Born Without A Left Arm
At Times She Felt A Left Hand That Was Not There
That Is Called A Phantom Hand
After An Amputation People Often Feel A Phantom Limb
Her Left Arm Was Missing From Birth And Not From An Amputation
The Researchers Studied The Shape Of Her Phantom Hand
A Phantom Limb Has No Physical Substance
Its Shape And Location Can Still Be Measured
She Held A Baton In Her Right Hand
With It She Pointed To Each Phantom Fingertip And Knuckle
A Camera Overhead Photographed Every Spot She Pointed To
She Said She Could Clearly Sense Where Her Phantom Hand Was
The Researchers Say The Origin Of Phantoms Is Strongly Debated
Vivid Phantoms Have Been Described In Others Born Without A Limb
So A Phantom Does Not Require A Memory Of Having The Limb
Phantom Limb Pain Has Also Been Reported In People Born Without Limbs
A 2020 Review Says The Pain Appears To Be More Common In Amputees
Their Limbs Were Lost In An Injury Or Removed In Surgery
A Quick Shoutout To Our Sponsor: WORLDQUANT
Here's What They Have For You 🧠
👇🏻
Interested in Quantitative Research?
The International Quant Championship (IQC) is one of the world's largest quantitative research competitions, bringing together participants from across the globe to test ideas, develop skills and engage with quantitative thinking.
Discover IQC and join a global community exploring quantitative research.
HOW THE BRAIN MAY CHANGE AFTER AN AMPUTATION 🗺️
A 2011 Review Says The Pain Was Once Seen As Mainly Psychiatric
Researchers Have Since Focused On Changes In The Nervous System
The Review Names The Cortex In Particular
Cortex Is The Name For The Outer Layer Of The Brain
Areas Of The Cortex Represent Different Parts Of The Body
The 2011 Review Describes What Happens After An Amputation
Neighboring Areas Expand Into The Area For The Amputated Limb
This Happens In The Areas That Handle Touch And Movement
Researchers Call This Cortical Reorganization
The Review Calls It Perhaps The Most Cited Reason For The Pain
A 2019 Review Presents The Same Idea As A Proposal
One Example Involves The Face And The Hand
The Area For The Face Is Next To The Area For The Hand
When An Arm Lost Its Sensory Nerve Input The Hand Area Changed
It Began Responding To Signals From The Face
Researchers In One Study Touched The Lips And Fingers Of Amputees
Each Of Them Had One Arm Amputated
In These Amputees The Lip Area Was Displaced Toward The Hand Area
The Closer It Was To The Hand Area The More Intense The Pain
A Quick Shoutout To Our Sponsor: TLDR
Here's What They Have For You
👇🏻
Why 1.1M+ readers open this AI newsletter every day
From ML engineers to founders, 1.1M+ readers use TLDR AI to spot new tools and research before they go mainstream. One free email, every morning.
RESEARCHERS DISAGREE ABOUT THE BRAIN CHANGES ⚖️
Some Studies Have Linked More Reorganization To More Pain
A Team In Germany Noted It Has Not Been Consistently Replicated
Replicated Means Other Studies Found The Same Result
Another Study Reported A Different Kind Of Link
Amputees In It Moved Or Imagined Moving A Phantom Hand
The Stronger The Pain The More Active The Area For That Hand
Its Authors Suggested The Area For The Missing Hand Was Preserved
The Team In Germany Called The Two Findings Seemingly Contradictory
What They Mean Is The Subject Of An Ongoing Scientific Debate
A 2026 Review Says Not Every Amputee Has Changes In The Cortex
Those Changes Are Also Not Consistently Linked To Pain Intensity
It Suggests Other Mechanisms Are Involved Too
The 2011 Review Describes A Mechanism In The Nerves
During An Amputation The Nerves In The Limb Are Cut
The Cut End Of A Nerve Can Form A Growth Called A Neuroma
Neuromas Can Become Overexcitable And Fire On Their Own
This Activity Is Thought To Be A Possible Source Of The Pain
Yet It Cannot Explain The Pain In People Born Without Limbs
In The 2011 Review No Single Mechanism Appears To Be Enough On Its Own
Many Experts Believe Several Mechanisms Are Likely Responsible
The 2026 Review Says The Pain Cannot Be Explained By One Body Site
Instead The Pain Is Tied To Changes In Several Places
They Include The Nerves And The Spinal Cord And The Brain
