system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: how are memories stored in our brains?
gpt
The short answer is that we don't exactly know yet, but we know a lot more than we used to.

The longer answer is that what we do know is that memories aren't stored in just in the hippocampus, a small section of the brain which we used to think was the memory center. The hippocampus still plays a role, but it isn't as singular as we thought.

More recent studies have shown we use multiple parts of our brains for the storage and compositions of memories. Brain scans have shown that multiple parts of the brain activate for memory recall, and the activated areas change depending on the nature of the memory. For instance, if you remember learning to work on cars with a parent, you might see activity in areas of the brain associated with knowledge about tools, emotional centers for thoughts of your parent, and your olfactory centers for thinking about the smells of the car fluids. This composite recall happens for 2 important reasons:

1) This has to do with how the brain processes information. As we learn things, and simply by thinking about things, our brains build and reinforce neural paths to connect parts of the brain associated with those thoughts, basically making as short a path as possible between sections of the brain. This allows the brain to use less energy to think about or do a particular thing. Very few sets of information is stored in any single part of the brain, which leads to reason 2.

2) By storing information throughout the brain, rather than in singular, organized locations, it allows the brain to maintain some functionality in the event of a brain injury. Imagine if all of our memories were stored in the hippocampus, as previously thought, and you got a concussion that damages it. Now, all of your memories are potentially gone. How could you still process anything other than basic, instinctual behaviors from infancy? But with how our brains evolved, we can still maintain significant amounts of neural ability even if we suffer an injury.