The human brain is a strange, enigmatic entity – a 1.3 kilogram (3-pound) witness to the world, it pilots us from the safety of our skull. It is a powerful product of evolution and a force to reckon with, but is also incredibly fragile and prone to error.
In steps the neuropathologist – the man behind the scalpel that slices and dices the brain in order to learn why it fails in some and not in others.
"Ideally, we need to get [the brain] back here in under 48 hours because the tissue starts to lose its quality after that time," said Steve Gentleman, professor of neuropathology at Imperial College London and scientific director for the Parkinson’s UK Brain Bank, in a video sent to IFLScience.
"If it arrives within 48 hours, we will bisect the brain down the middle, half of it will be frozen and the other half is fixed and used for diagnostics."
The brain is arguably the center of the self, the “machine” that drives our personality and who we are, and so you may ask: Why would anyone donate their brain to science? Well, to answer that question, we asked someone who has actually donated her brain.
Meg Kierek-Bell, whose brain will go Parkinson’s UK Brain Bank, based in London, when she dies, has explored and answered this question for herself. A retired nurse who began cadet nurse training when she was 17, she now lives with her husband of 40 years, a poodle, and a Bengal cat.
It may, at first, seem like an odd pairing for someone like her to donate her brain to science, but Kierek-Bell has both a personal and practical way of looking at it.
It began when she noticed something unsettling about her husband.
"I noticed that my husband had a tremor of his right hand, and it was really irritating. I said to Robin 'you know, that is a tremor. You’ll have to go the doctor.'"
After a few gaffe diagnoses by doctors, they finally received the one that fit: At 52 years old, her husband Robin was officially diagnosed with early-onset Parkinson’s disease.
Parkinson’s disease is a neurodegenerative brain disorder. Symptoms typically include tremors, shaking, and difficulty with balance.
It is linked to the decreased production of dopamine in the substantia nigra – a region of the midbrain that influences movement and reward. Although the disease is not fatal, quality of life is reduced, with as many as 10 million people worldwide living with the condition.
From Statistic To Realty
For Robin, what was once simply a statistic on a sheet became his reality. The symptoms seeped into his work despite his best efforts.
When he went to work as a director of education in further education, his tremor was "very, very marked," said Kierek-Bell. "He was always having to put his hand in his pocket."
But he could only pocket the problem for so long.
The young students he works with in further education are typically studying after they fail to meet grades in the school system. This means "you have to remain in control, but if they see you shaking, they say: 'Oh you’re frightened of me, sir.'"
Of course, that was far from the case, but it didn’t make dealing with difficult students any easier.
"Even if you are on medication, that medication doesn’t always control Parkinson’s. It is as if you are on and off. You’re on your medication, but you’re experiencing an off period, which means the medication isn’t working as it should."
This is one of the many reasons why brain donations are crucial. While we’ve come a long way since the bloodletting and blistering treatments of the late 1800s, scientists are still in the dark as to how to correct the disease. We’ve gotten flashes of insight from animal research, directing us where to focus next, but a cure remains elusive and questions linger.
Why will certain people develop Parkinson’s, uncontrollable tremors shaking their body like earthquakes? Why will others develop Alzheimer’s, their memories slowly slipping away from them? And why does the medication work for some, but not the others?
It is these very questions that brain banks around the world help facilitate investigations of. In fact, the Parkinson's UK Brain Bank is set to reach a milestone this October, with over 1,000 brain donations. This number is a benchmark of all the formative research done to date and still to come.
The beauty, yet difficulty, of our brains is that they are unique like snowflakes, each as individual as the person imbued with its personality. Yet, there are commonalities that neuropathologists can look for. This is why brain banks often accept brains from people without certain conditions like Kierek-Bell – they are, so to speak, "control" brains.
What Happens To My Brain?
So you’ve donated your brain. Or maybe you’re curious about doing so. Or perhaps you’re just fascinated by those who do.
Once a person dies, scientists are pressed for time: They have just 48 hours to collect the brain before it starts to deteriorate. When it arrives, they bisect it down the middle – half will be frozen and the other half fixed in formalin for diagnostics.
"Once the tissue has been fixed for four or five weeks, I will come along and do the diagnostic cut up," explained Dr Gentleman. "So what I’m doing is I’m looking to see any evidence of pathological changes while I’m doing the dissection.
"I dissect out those key areas where we know pathology might be found. The technicians will embed the small pieces of tissue in paraffin wax. They will then be able to cut very, very fine sections – 7 microns."
To contribute to as many studies as possible, each brain is divided into around 250 samples, according to the Parkinson’s UK Brain Bank site.
So who gets to prod, poke, and investigate the pieces of your noggin?
The tissue is given to researchers all around the world who are studying Parkinson’s. Due to the mutable nature of research, the brain bank may need to collect samples of other tissue in the future, such as those from the skin or gut.
"If this happens, we will always ask your next-of-kin’s permission before removing any material," says Parkinson’s UK Brain Bank. The removal of the brain and spinal cord is performed in a finely executed manner that "will not affect the appearance of the body."
All that's collected is the brain, spinal cord, and a sample of cerebrospinal fluid – the clear liquid that buffers the brain and spinal cord.
"All this detail is put in a report," added Dr Gentleman, "along with a summary of the clinical history of the patient, which is done by one of the neurologists and that goes with the tissue – anonymized of course – to the researchers, so they know exactly what they are dealing with in terms of the tissue they’ve got."
Incredibly, just one brain donated to science can be used in up to 50 research studies.
Why Do It?
The post-mortem brain provides scientists with a way to probe the brain via an alternative means than imaging and animal testing. Although these tried-and-true methods are extremely useful in their own right, they have their limitations.
For many, then, brain donation is a way to make a lasting contribution to science. It is a gesture of solidarity and a means to help others who are afflicted with life-long diseases with no cure.
"I like the idea that, as an act of humanity, we all donate," said Kierek-Bell, whose husband retired from further education (although one could make a case he is still teaching to this day, as he shares his experience of Parkinson's with others).
Unfortunately, there is a shortage of human brain donations. For many who choose not to donate, it’s because it requires them to look at their own mortality or to envision their body being used in some way after death.
For others who have chosen the route of donation, it is a way of making an everlasting contribution when the mortal self is no longer there. It is a final gift.
In the end, it’s your brain’s decision whether it wants to donate itself to science. And in that, there is something beautiful.