I just don’t quite understand, and perhaps no one really does. But what do we know? if computers store memories as ones and zeros how do we do it? And if all of your cells are dead and re-placed by new ones every what is it, 10 years? then how do we have memories that are older than that. can the brain train the newer brain cells to store the same memories and if so are there two copies of the same memory? I’m losing my mind guys thank you
In: Biology
That’s a big question with a lot of answers. The first answer is that the brain actually has a lot of forms of “memory” and they all work a little differently. One common way to make a big division in types of memory is between “declarative” and “procedural” memory. Declarative memory is, broadly, your ability to actively know things. You remember the capital of the US, or what you had for breakfast. Procedural memory is your brain getting better at doing things. If you practice throwing a ball a thousand times, you’ll get better at it, but you’ll have a hard time really saying what you’re doing differently. You’re just doing it “better”.
One way declarative memory works centers on a part of the brain called the hippocampus. The hippocampus likes to draw connections and associations between things. It does this by taking in a lot sensory input from the rest of your brain and linking events that happen at the same time. Building these associations creates a sort of “map” of the world and how events happen in them and in what order. The nuts and bolts of this is very complicated, but some important parts are changes in the strength of connections between neurons and creating or destroying connections between neurons. Eventually these associations are communicated more broadly to the rest of your brain, especially the cortex. So long term memories can’t really be pinned down to one place in the brain.
Procedural memory is a little different and works through a lot of other parts of your brain like the striatum or cerebellum. But again at it’s heart relies on changing the strength and location of connections between cells in the brain.
An interesting aspect of this is that memory is not stored in any static way. Its the collective activity of neurons in a group. So it’s often said that every time you access a memory you’re changing it a little. Your own memory probably isn’t as immutable as you think.
My last note is that the “10 years completely new cells” thing is a very very broad generalization. Your neurons are a highly stable population of cells which do not really turnover. It’s actually a subject of pretty serious debate right now as to whether human grow new neurons at all during adulthood.
This may have been a bit complicated as an “eli5”, but hopefully you got the general shape of a really complicated but fascinating part of the brain.
tl;dr: Changes in connection strength between neurons is the brains way of storing information.
Latest Answers