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by kashif_hn 4934 days ago
I have heard somewhere that human memory size is not known till date.
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http://www.scientificamerican.com/article.cfm?id=what-is-the...

The human brain consists of about one billion neurons. Each neuron forms about 1,000 connections to other neurons, amounting to more than a trillion connections. If each neuron could only help store a single memory, running out of space would be a problem. You might have only a few gigabytes of storage space, similar to the space in an iPod or a USB flash drive. Yet neurons combine so that each one helps with many memories at a time, exponentially increasing the brain’s memory storage capacity to something closer to around 2.5 petabytes (or a million gigabytes)

That said, I don't think you can make a simple comparison between the bits in a computer and the memories in a human brain. I think that the human brain beats the computer in terms of raw storage capacity, since a single brain can continue accumulating data for a lifetime without needing an upgrade, but the computer is more efficient at storing the bare minimum. For example, a computer can store a simple concept like a picture of a plate of spaghetti in a 3KB file. The human brain might store that image, along with a memory of the smell, taste, and emotions related to spaghetti. It might also connect that memory to different places you've eaten it, and how they compared. In a computer system, it would be impractical to store and retrieve this extra metadate, but the brain seems to be able to.

I remember learning in a college class on cognitive science that some scientists believe that human memory is permanent, in that long term memories don't get erased, they just get harder to access. It makes sense that when something is on the tip of your tongue and you remember it later on that it was probably just a slow query.