Who can forget the lines from the movie, Sixth Sense, “Walking around like regular people… They don’t know they’re dead.” As it turns out, there are people walking around not dead but without half their brains. That is possible? That is possible.
Our brains begin to shrink when we hit our 40s and is made worse by lack of sleep and boozing – which isn’t good news for US President Donald Trump aged 74.
Within our body, the brain is the most vital organ – controlling all our important bodily functions.
It is key to our movement, emotions and even our breathing and heart rate.
But what many people don’t realise is that it is possible to exist with half of the brain missing; and unless someone with this experienced problems and had a brain scan they may never even realise.
Dr. Jenny Barnett has studied what the brain can do, how it can develop and crucially; when it begins to shrink and our brain cells start to die.
She explained that while the brain grows in early adulthood, all functions begin to decline by the time we reach around 40.
Drinking excess alcohol, particularly as a teenager, and not getting enough sleep; can also seriously impact the performance of the brain and mean it never reaches its peak.
But while some people believe the brain’s function is declining because of our reliance on technology, Jenny thinks not having to worry about tasks like memorising phone numbers actually frees up our brain to develop and evolve – opening up possibilities for the brain to do even more in future.
“I think we have always adapted to a changing environment and some of the skills we are gaining from interacting with technology could be a positive thing,” said Jenny. “We ask should we be playing games for hours on end? Should we be worried about it? But playing these games is where you have to learn coordination.
“We know that sitting on our backsides is not good for your health. But should we worry children are playing games; instead of reading a book? There’s possibly just as much skill and learning involved.
“It’s not necessarily negative, it’s more about people who spend more time doing fine detailed work, and those who spend hours gaming; the part of their brains they use for this will be larger. ”
Some functions of the brain – such as memory – have now been taken over by technology.
For example mobile phones store numbers in their internal memory; meaning we no longer have to remember them.
But as humans our brains have also evolved as the physical tasks we do have changed.
Our brains and bodies have evolved to switch from doing more manual physical work; to tasks confined more to offices and the brain has adapted – and will keep adapting – to do this.
And Jenny said modern life and techniques could have a greater impact on our brains – even changing the size of them.
“Historically our brains have been getting smaller over the last few thousands of years,” added Jenny.
“But it may be that our brains can get bigger in future. In the past the size of the brain was constrained by the size of the head; which had to get through a woman’s pelvis. But now we have caesareans that evolutionary constraint has gone.”
The brain is considered ‘plastic’ which means it can both develop, and respond and adapt to trauma; – particularly in children when it is still growing.
This means some who may have been born with part of their brain missing may never realise unless they experience a problem as the brain will adapt to function.
It also means children are more likely to recover from a brain injury than adults.
Many who have had brain injuries manage incredibly well – and Jenny added, many of us “could be walking round with quite big holes in our brains; which we have had early on – and if we had never had a brain scan how would we know?
“People are walking around with substantial parts of their brain missing and holes in their brains.”
She points to the example of Aiden Gallagher who had half of his brain removed by surgeons; after he started suffering up to a dozen seizures a day and was forgetting the alphabet.
Little Aiden had 50% of his brain removed, a procedure known as a hemispherectomy, when he was just three; and by the age of 10 was going to school and playing sports as normal.
Jenny added: “I think there are people walking round with as much as 60 per cent of their brains missing.
If you had more than 50 per cent of your brain missing you might still be able to walk and talk.
Often this only comes to people’s notice if they are suffering from something like epilepsy; or seizures or not being able to coordinate properly.
For those who have suffered a brain injury early in their life; the brain has an amazing ability when you are young to grow to compensate for that. We say the brain is pretty plastic.
The earlier you have an injury, the more plastic it is.
“However in adults a brain injury is far more serious. Once we reach adulthood we grow very few new neurons; so if something happens and a big chunk of the brain is affected, the cells are dead in this section and there is generally no bringing them back.”
But while it is possible to live a good quality of life with half missing, Jenny cautions against believing the common myth; that we only use 10 per cent of our brains – a ‘fact’ she says is “definitely not true.”
She says due to the brain’s complexity, the amount we use is not yet totally clear.
She also said that while our brains are still growing in early adulthood, cells are starting to die off by the time we reach our mid 30s; – making the senior position of people in their 70s, such as US President Donald Trump, a subject much debated.
The brain begins to shrink in size when adults get to around 40.
With little children their memories are great.
For six and seven year olds their memories are as good as they will ever be.
Memory is always made by this point and by the time you hit 40 it starts to decline rapidly.
HOW MUCH BRAIN DO WE REALLY NEED
“Your brain is still developing perhaps into your late 20s and early 30s.
“But after about 60 all aspects of your brain function are declining.
Things like memory, connections, learning decision making – all the core areas we think are good things – are showing decline by that age.
It’s very interesting when you think of the age of people who make up boards of big companies, or the US President for example.
Broadly speaking people in their 60s often hold these powerful positions.
They don’t have the processing power of someone in their 20s.
Perhaps they do have wisdom and the ability to gauge social interactions.”
Alcohol is also a particular problem – with booze impacting the development of the brain; particularly for teenagers.
“The added danger of drinking to excess as a teenager is that you haven’t yet reached your peak ability and if you cause some damage; you may never reach that peak.
“For example if you have 100% memory that may drop down to 95%.
If you are still developing you may only have reached 70%.”
But Jenny said more than alcohol, sleep deprivation is a more serious problem – affecting cognitive function.