brain to a computer:We often imagine that human consciousness is as simple as input and output of electrical signals within a network of processing units – therefore comparable to a computer. Reality,
however, is much more complicated. For starters, we don’t actually know how much information the human brain can hold.
Two years ago, a team at the Allen Institute for Brain Science in Seattle, US, mapped the 3D structure of all the neurons (brain cells) comprised in one cubic millimetre of the brain of a mouse – a milestone considered extraordinary.
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brain to a computer
Within this minuscule cube of brain tissue, the size of a grain of sand, the researchers counted more than 100,000 neurons and more than a billion connections between them. They managed to record the corresponding information on computers, including the shape and configuration of each neuron and connection, which required two petabytes, or two million gigabytes of storage. And to do this, their automated microscopes had to collect 100 million images of 25,000 slices of the minuscule sample continuously over several months.
Now if this is what it takes to store the full physical information of neurons and their connections in one cubic millimetre of mouse brain.
you can perhaps imagine that the collection of this information from the human brain is not going to be a walk in the park.
Data extraction and storage, however, is not the only challenge. For a computer to resemble the brain’s mode of operation, it would need to access any and all the stored information in a very short amount of time:
the information would need to be stored in its random access memory (RAM), rather than on traditional hard disks. But if we tried to store the amount of data the researchers gathered in a computer’s RAM, it would occupy 12.5 times the capacity of the largest single-memory computer (a computer that is built around memory, rather than processing) ever built.
The human brain contains about 100 billion neurons (as many stars as could be counted in the Milky way)
one million times those contained in our cubic millimetre of mouse brain. And the estimated number of connections is a staggering ten to the power of 15. That is ten followed by 15 zeroes – a number comparable to the individual grains contained in a two meter thick layer of sand on a 1km-long beach.
A question of space
If we don’t even know how much information storage a human brain can hold, you can imagine how hard it would be to transfer it into a computer. You’d have to first translate the information into a code that the computer can read and use once it is stored. Any error in doing so would probably prove fatal.
A simple rule of information storage is that you need to make sure you have enough space to store all the information you need to transfer before you start?
If not, you would have to know exactly the order of importance of the information you are storing
how it is organised, which is far from being the case for brain data.
If you don’t know how much information you need to store when you start, you may run out of space before the transfer is complete, which could mean that the information string may be corrupt or impossible for a computer to use. Also, all data would have to be stored in at least two (if not three) copies, to prevent the disastrous consequences of potential data loss.
This is only one problem. If you were paying attention when I described the extraordinary achievement of researchers who managed to fully store the 3D structure of the network of neurons in a tiny bit of mouse brain.
you will know that this was done from 25,000 (extremely thin) slices of tissue.
The same technique would have to be applied to your brain, because only very coarse information can be retrieved from brain scans.
Information in the brain is stored in every detail of its physical structure of the connections between neurons:
their size and shape, as well as the number and location of connections between them. But would you consent to your brain being sliced in that way?
brain to a computer
Even if would agree that we slice your brain into extremely thin slices,
it is highly unlikely that the full volume of your brain could ever be cut with enough precision and be correctly “reassembled”. The brain of a man has a volume of about 1.26 million cubic millimetres.
If I haven’t already dissuaded you from trying the procedure, consider what happens when taking time into account.
A question of time
After we die, our brains quickly undergo major changes that are both chemical and structural. When neurons die they soon lose their ability to communicate, and their structural . functional properties are quickly modified – meaning that they no longer display the properties that they exhibit when we are alive. But even more problematic is the fact that our brain ages.