What is the psychology behind forgetting something? How does the brain suddenly remember something you hadn’t thought about in years?
In: Biology
I was told it’s like a trail in the woods. If it’s used or thought of often the trail is there and easy to see or remember. If you don’t use it often the train becomes hard to see
This may be very out of date, because college was WAY too long ago. But, in my neuro-psych class, one of the accepted frameworks for how the brain worked was the “spreading activation model.” Think of it like a lightning strike that goes off in your brain, with each fork of the lightning being a different neuron. When you have a have a thought, it sparks off all of the other related neurons, which spark off other neurons, and it kinda cascades out like that. Everything that is lit up is associated with the original thought, and it is remembered.
But some things don’t have a lot of pathways there. If I asked you to remember a random date, you may draw a blank. There’s not a lot of linked pathways in your brain to that specific date, so nothing really fires. However, let’s say that was the date that an important event in your life. It could be a good event (like a first date, or a new job, or something), it could be a “bad” event (death of a loved one, divorce, etc).
Suddenly, you may have a whole lot of activation, and remember random things. You may suddenly think about or even see the couch that was in the room where the event happened. That couch wasn’t very important normally, but for some reason it’s related to the memory, and now you think about it.
I’ve always been fascinated by the fact that I can just randomly remember dreams I’ve had years or even decades ago. Like they suddenly just pop into my head and I’m like, why?
It’s not like I’m thinking about dreams, I’ll just be doing something and suddenly I’ll remember a dream. Sometimes I do get a deja vu feeling and then it makes sense, like I’ve been here before, or dreamed this. But that’s rare.
As my psyche professor put it “the brain stores memories as clues, not information when it’s not procedural memory”.
It’s a chain of associations, an emotion, an image, a feeling or a smell can trigger your memory. Smell and touch are strong due to evolution (the olfactory nerves bypass most executive functions of the brain, that’s why you’ll react to a bad smell faster than a bad image).
If you have a weak connection to an event (or it’s routine) you can do things like put your keys down and then forget where you did it. Your brain made a decision that something else was important or you were preoccupied with something and that memory goes away.
But the smell of a marker could cause your brain to make connections that make you remember grade school. As
[JesterBarelyKnowHer](https://www.reddit.com/user/JesterBarelyKnowHer/) put it, the “lighting strike” causes related neurons to fire. Thus a smelly marker leads you to thinking about 3rd period English and that test you bombed.
Your brain doesn’t work like a computer or filing cabinet where memories are stored neatly in a row. Instead, when you try to remember something your brain tries to rebuild the memory. A memory is stored as a web of neurons with connections between them. When your brain experiences something, the neurons flare up in a pattern. Each time those neurons flare, the connections between them get stronger, which is why you remember things more easily when you’ve repeated them over and over. Of course this doesn’t work perfectly, and your brain can create incorrect connections where they don’t belong, or the connections themselves can degrade if they aren’t flared for a long time.
Disclaimer: FAR from an expert.
As I’ve generally through about it. A memory is essentially an electrical current routed a certain way through the brains grey matter (neurons).A certain sequence of neurons activated by a passing current is the mechanism for both the original “memory” to be recorded, the same path of neurons are fired each time you recall something.
The brain being an absolute universe worth of these pathways, the chances of randomly “loosing” a path gets quite high. It’s still chemically there though. Memory is likely about linking together certain pieces of (meta) data. So… rather than having a perfect image of a red bicycle, it’s properties are “remembered” by the sequence of neurons that need to fire to “rebuild” the image in your minds eye.
Strong memories have many “hooks” into them so the red bicycle is associated with: A town you lived it, the person who gave it you or who you spent time with about it and all the links going out from that in a tangled mess of bits of data that are parts of different memories. At the point something else causes a particular neuron to fire, there’s a chance an “old” activation pathway through the network of neurons is fired and you recall an old memory.
I’m sure there’s an AWFUL lot more to it than that and asking the question on a more technical level probably would get a lot more depth/etc but… that always seemed sensible to me as to how the brain likely works. It’s a collection of billions, upon billions of neurons. I’d think as you learn new “properties” of objects they’re stored and organised down to a pretty minuscule level and recall is the electrical part of the brain re-linking each of these properties into a memory/object/skill/picture/thought.
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