People who stay mentally sharp in old age have bigger brain cells than people decades younger than them, study finds
- They have special neurons larger than those in people 30 years younger
- The neurons also do not have ‘tau tangles’, a tell-tale sign of Alzheimer’s
- Researchers cut open postmortem brains of elderly people to compare
People who stay mentally sharp and healthy into their eighties have bigger brain cells, a study suggests.
Our neurons slowly start to shrink as we age, which is why we tend to slow down in our senior years.
But brain cells in so-called ‘super-agers’ are larger than those in people 20 to 30 years younger than them, scientists showed for the first time.
It is not clear if people are born with larger neurons or if they are just more durable.
But the discovery of this unique biological signature could one day open the door to screening programs and treatments for the memory disorder, scientists hope.
Super-agers have the brainpower of those 20-30 years their junior, thanks to neurons in their brain that are larger than average from birth (stock image)
Lead author of the new study Dr Tamar Gefen, from Northwestern University in Chicago, said: ‘To understand how and why people may be resistant to developing Alzheimer’s disease, it is important to closely investigate the postmortem brains of super agers.
‘What makes super agers’ brains unique? How can we harness their biologic traits to help elderly stave off Alzheimer’s disease?’
The scientists cut open the postmortem brains of six super-ager donors to see what makes them unique.
They compared them to a control group of seven average patients of the same age, along with six people in their 50s and 60s, and five individuals with early stages of Alzheimer’s.
They examined the entorhinal cortex, the brain’s memory control center and one of the first spots Alzheimer’s disease affects.
They measured the size of neurons and looked for tau tangles – a type of plaque associated with dementia.
The special neurons appeared to be relatively void of the protein.
Dr Gefen added: ‘The remarkable observation that ‘super-agers’ showed larger neurons than their younger peers may imply that large cells were present from birth and are maintained structurally throughout their lives.
‘We conclude that larger neurons are a biological signature of the super-ager trajectory.’
The findings were published in The Journal of Neuroscience.
What is Alzheimer’s?
Alzheimer’s disease is a progressive, degenerative disease of the brain, in which build-up of abnormal proteins causes nerve cells to die.
This disrupts the transmitters that carry messages, and causes the brain to shrink.
More than 5 million people suffer from the disease in the US, where it is the 6th leading cause of death, and more than 1 million Britons have it.
As brain cells die, the functions they provide are lost.
That includes memory, orientation and the ability to think and reason.
The progress of the disease is slow and gradual.
On average, patients live five to seven years after diagnosis, but some may live for ten to 15 years.
- Loss of short-term memory
- Behavioral changes
- Mood swings
- Difficulties dealing with money or making a phone call
- Severe memory loss, forgetting close family members, familiar objects or places
- Becoming anxious and frustrated over inability to make sense of the world, leading to aggressive behavior
- Eventually lose ability to walk
- May have problems eating
- The majority will eventually need 24-hour care
Source: Alzheimer’s Association