If someone could have their life extended with no limit, would their brain eventually run out of storage space?
Hillary Shaw
Newport, Shropshire, UK
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Memory storage can’t be in units of less than one atom, so if our brains stored memories linearly, like book text, at some point it would be full.
However, we don’t do this. We have memory hierarchies, so I don’t need to remember everything in my encyclopedias, just where I put them, what concepts/words those 26 or so little characters make and the order of the alphabet.
Likewise, I can write my life events down in a diary. If I can’t remember where I put all my books, I can make a list or order them some way. The internet gives me access to even more knowledge if I remember how to switch the computer on. So I only need remember a few thousand words (or where I keep the dictionary) to open up infinitely extendable, readily accessible memories, even if I live for a trillion trillion years.
Robert Law
Hong Kong, China
What is memory? As far as we know, it is a collection of neurocircuits with multiple neurons participating, which has the specific function of recording/storing events/knowledge in the past that can be retrieved at any time – even during our sleep, creating dreams.
If you think about it, during your lifetime, from birth to, say, 80, the amount of day-to-day information that is fed to your brain is simply (and literally) mind-boggling. If the brain were a simple computer, it would have physically run of storage space when you were a few years old. Therefore, your brain must function in a way where all the information that is being fed into it is constantly deleted after a short period of time. To remember something, you have to repeatedly feed that same information (think of revising for exams) to your brain.
This should mean that, no matter how old you get, you will never run out of storage space because old (and not-so-old) memories are constantly being deleted to make way for new ones.
However, when we get old, we tend to remember the past more than recent events. Could that be a sign of the brain ageing and running out of storage space, so there is no more space for short-term memories?
This may be true in cases of people with early dementia. Those affected may not remember whether they have just eaten a meal, but they can vividly recall events that happened when they were very young.
So, the answer to the question is: as long as the brain remains healthy just like the rest of the body, it won’t run out of storage space, but an ageing brain may.
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