9 Strange Cases Where People Survived With Pieces Of Their Brain Missing

Modern medicine can help us survive many injuries that would have been catastrophic in the past. However, while hearts and livers can be transplanted and arms and legs can be replaced with increasingly advanced prostheses, there's one part of the body that still seems to be susceptible to injuries that can't be fixed quite as easily. That body part is, of course, the brain.

Head injuries are notoriously dangerous: in 2021, traumatic brain injuries killed 69,473 people in the U.S. alone. With this knowledge, and because the brain controls pretty much everything in your body, it's easy to suspect that when the organ receives enough damage, it's an immediate game over. However, this isn't quite true.

While damage to the brain is never something to be scoffed at, medical history knows a surprisingly large number of cases where people were able to survive — and in some cases, even live a full life — with parts of their brain missing.

How much brain would you say it's possible to live without? In the case of one 44-year-old French man — who remains unnamed for reasons that may soon be obvious — the answer is 90%. What's more, absolutely nothing indicated that the individual in question was operating with just 10% of his brain until he started having leg problems one day, and decided to have the situation checked out. As it turned out, the man's real problem was an incredibly severe case of hydrocephalus, aka cerebrospinal fluid that had been building up in his head. In fact, his skull was essentially filled with this liquid, which had replaced the vast majority of his brain tissue. 

The story surfaced in 2007, and apart from the lower limb issues (which he had first experienced when he was 14), the man didn't seem to suffer any particular side effects. His intelligence quotient was understandably not at Einstein levels — verbal IQ 84, performance IQ 70 — but he had still built a perfectly cozy life: The guy with just a tenth of a regular brain at his disposal was a married man with two kids and a white-collar job.

Understandably, the situation has perplexed specialists. "It is truly incredible that the brain can continue to function, more or less, within the normal range — with probably many fewer neurons than in a typical brain," cognitive psychologist Axel Cleeremans said in an interview on CBC Radio's "As It Happens" show. 

Phineas Gage was born in 1823, but his story really started in 1848, when he was working for the Rutland and Burlington Railroad company in Vermont. On September 13, he was setting up an explosive charge when he made a mistake and the tamping rod he used to pack the gunpowder ignited a blast. This sent the rod on an 82-foot flight path that went right through poor Gage; in through the cheek, out through the top of his head.

The rod wasn't what you'd call small. Its measurements were 3.58 feet in length, 1.25 inches in width, and 13.25 pounds in weight, so you can imagine what it could have done to Gage's brain. Yet, he survived the ordeal with just a blind left eye and some facial damage ... or so it seemed, at least. 

What actually happened to his health status and brain after the incident is at least partially shrouded in mystery. We know that he was able to speak immediately after the accident, but 10 days afterwards, an infection wrecked his health for a month. Again, he recovered, with physical and mental faculties apparently unchanged. However, some who knew him claimed that Gage's personality had changed for the worse. It's unclear whether his new impulsive, unpleasant nature was a permanent development, but changed man or not, Gage remained in the workforce until his health declined in 1859. He died of seizures in 1860. 

There are two temporal lobes in every healthy brain, located in the temple areas. They control your visual, language, and communication skills, and are crucial in the brain's ability to process memories and emotions. Some conditions, like certain types of epilepsy, may require temporal lobe surgery to remove the front part of the lobe to prevent seizures, but operating on that area comes with a laundry list of potential side effects. Knowing all this, imagine how difficult life would be for a person with one temporal lobe completely out of the picture. Surely, that would be fatal, or at the very least take a massive chunk of a person's basic tool kit away for good? 

Not necessarily. In 2016, a U.S. woman who grew up without her left temporal lobe contacted researchers at the Massachusetts Institute of Technology after reading about them. After the woman, who's only known as "EG," revealed her condition, they put her in touch with a cognitive neuroscientist and the two started looking at the peculiarities of her brain.  

As it turns out, EG had lived a perfectly normal, academically and professionally successful life despite a very real chunk of her brain missing — probably due to a stroke she had when she was just a baby. It seems that since the injury happened at a young age, EG's developing brain was able to "rewire" itself to function normally, despite quite literally missing a piece of the puzzle. 

Christie Raleigh Crossley is good at what she does: As of 2024, she had two gold medals, two silver ones, and one bronze as a Paralympian swimmer. Even before her Paralympics success, she was a good swimmer who had to overcome two consecutive car accidents in 2007 and 2008, the first of which damaged her spine. The second had repercussions, too: In 2018, a head injury during a snowball fight caused partial paralysis, the cause of which turned out to be a brain blood tumor that had been growing since the 2008 accident. 

Removing the tumor left her with mobility issues and a literal hole in her brain. This caused her to move to para swimming in 2022, and she won all of her five Paralympic medals at the 2024 Paris games. Unfortunately, this glory and the fact that her disability isn't always visible had their downsides in the form of detractors.

"I had a blood tumor in my brain that had been killing the brain as it took over that area, and then they removed it. And so now I've just got a nice hole," Crossley told The New York Times in 2024. "I have become a lightning rod of sorts, where people are like, 'She's so fast,' and they don't see the disability all the time. It's a pretty toxic environment. But I get it. I'm their competition and everything is money to everybody."

John Hinckley Jr.'s attempt to assassinate President Ronald Reagan on March 30, 1981 was unsuccessful, but he nevertheless injured four people: Reagan himself, police officer Thomas Delahanty, Secret Service Agent Timothy McCarthy, and Reagan's Press Secretary James Brady. Out of those four, Brady's injuries were far and away the most serious. One of Hinckley's explosive "devastator" bullets hit the press secretary in the left side of his forehead, damaging both of his brain's frontal lobes, right temporal lobe, and the corpus callosum area that connects the left and right side of the brain.   

After extensive surgery and rehabilitation, Brady survived. While his mental faculties returned to a considerable degree, he spent the rest of his life in a wheelchair because the left side of his body never recovered its full strength. Such disadvantages didn't set Brady back, though. He died in 2014 at age 73, and had a hand in American politics for a long time after his injury.   

Impressively, Brady was able to turn his tragedy into a force of good. After advocating gun control for years, he and his wife Sarah were instrumental in the creation of the 1993 Brady Law, which required a five-day waiting period before selling firearms to unlicensed buyers in states without existing, valid background check methods. The law was only in effect until 1998, but during this time, there were an estimated 10,000 fewer gunshot deaths than during the five years before the law.  

In 1981, a 30-year-old man called Kent Cochrane had a motorcycle accident that was just about as bad as it could be without resulting in a fatality. He already had a history of head injuries, but the one he received this time was particularly severe and damaged his brain in a number of ways. Most notably, he completely lost his hippocampus. 

The hippocampus is the area of the brain that deals with all things related to learning and memory, so researchers weren't exactly shocked when Cochrane — who became known as subject "K.C." in amnesia research — could make no more new memories, and lost the bulk of his existing ones as well. However, it soon turned out that his memory wasn't entirely gone — he could retain factual, "semantic" memories that weren't associated with emotions or other personal context. For instance, he could recall that some of his relatives had died or gotten married, but the actual significance of these events or his own involvement in them rang no bells whatsoever.

Cochrane's brain and highly specific memory issues eventually helped neuroscientific researchers to understand that the memories he was able to retain were actually connected to his still-intact parahippocampus. They also discovered that his brain was still able to slowly learn new things, but in a way where he didn't fully understand what said things were — they simply seemed familiar to him. He lived to the age of 62.

The cerebellum is a part of the brain located at the back of the head, and is one of its bigger mysteries. Home to roughly 50% of the brain's neurons, it's a hotbed of coordination that interacts with the nervous and muscular systems and affects an array of our functions, such as movement, timing, and balance. As such, having to live without it sounds outright impossible, unless you account for the brain's extraordinary ability to rewire itself, at least in some cases. 

In 2014, a 24-year-old Chinese woman was found to be missing her entire cerebellum when she checked into a hospital after feeling dizzy and nauseous. She had been living an entirely ordinary life up to that point, apart from some early developmental slowness. This is especially noteworthy because while this particular condition is extremely rare, it has been known to happen on occasion and even has a name of its own: complete primary cerebellar agenesis. What's more, it's usually fatal, or at the very least causes severe issues.  

The life of this particular woman hadn't been completely free of incident, either. She couldn't speak properly until she was 6 years old, and couldn't walk without being assisted until a year later. Her walk remained uneven beyond that, and she didn't receive education. However, in the grand scheme of things, her symptoms were very minor. It says something that even her mother hadn't suspected that anything was seriously wrong with her. 

Surviving without a considerable part of one's brain due to a pre-existing condition is one thing, but surely it's impossible for a person to survive and live a full life after doctors remove half of their brain? Surprisingly, this has also happened to a patient called Mora Leeb, and the drastic procedure became necessary at a young age.

Unbeknownst to anyone, Leeb had a stroke before she was born, and was mere months old when she started having multiple seizures a day. When doctors looked into the situation, it turned out that most of her brain's left hemisphere was dead and what was left was causing the seizures. In an effort to fix the issue, the damaged hemisphere was removed when Leeb was 9 months old. "Basically the surgery created a newborn," Leeb's mother Ann Leeb told NPR. "She could no longer roll over. She could no longer smile. It was almost like a restart."

The removal of half her brain caused a temporary paralysis on the right side of Leeb's body and her development was a little slower than usual — she was over 6 years old when she started speaking with full sentences — but there's no question that her remaining hemisphere took up the slack to an amazing degree. As of 2023, the 15-year-old Mora was a completely normal teenager save for her slightly stilted speech patterns and language processing, caused by her brain's unique wiring. 

Here's an amazing survival story that might just be the most amazing on our list, but be warned, the tale of Trevor Judge Waltrip is also quite possibly the most tragic one here. Waltnip, you see, was born with just his brain stem, with both of his cerebral hemispheres replaced with cerebrospinal fluid, which is the liquid that flows in the brain and spinal cord, as well as around the brain to protect it. 

The brain stem is responsible for vital functions and the neuromuscular side of several basic activities, but Waltrip's condition was understandably very extreme, and he was both blind and unable to speak. However, his family says he was far from unresponsive. "He's so alert and hates to be alone. He'll sense that, too," his mother Elizabeth Waltrip told KSLA News. 

Babies with this kind of condition often die before birth, and because of this, Waltrip was only expected to survive mere days. However, doctors were completely wrong in their estimations. Waltrip died in 2014 at age 12 — still tragically young, but far older than anyone could have anticipated.