nazz
Doubting Thomas
Thanks in no small part to the problems of the computer metaphor, people tend to think of memories as "stored" like they are in a computer. A memory for "dog" is stored in this sequence over here, a memory for "car" over here, etc. That's not the way that the brain works. Storage relies on a steady-state. A bit that is part of the representation of some variable must be either 0 or 1. If it changes, then that is no longer the same variable. In a computer, data is represented by the permanent (so long as the representation doesn't change) state of specific bits. In the brain, there is nothing akin to bits. That's because the representation is patterns of firing.
You may have heard of the Stroop test. Usually, it involves looking at words like red, blue, green, etc., with each word being a particular color:
The task is to give the color of the words not what the word says.
Let's imagine that we simply had some place in the brain where "blue" was stored. Then all we'd have to do is call up that memory. It shouldn't matter what the word spells. Only it does. That's because our information about the color depends on neural activity which corresponds to the perception of the color, not just the concept of the color or the color's spelling. In reaction time tests, people process abstract words faster if they just saw a corresponding item first such as first seeing an upward pointing arrow and then seeing the word "hope" because part of the way we represent "hope" is upward direction. By overlapping concepts like this, we basically "overlap" memories of concepts. The concept of "hope" is represented by certain patterns that also represent "up". At a very basic level, when certain features are presented together or represented in the brain by sensorimotor activation that occurs at the same time, they get represented by correlations between the firing of lots of neurons. In a very real way, we can store an unlimited number of concepts because of the way we are able to overlap the representation of information about these concepts. Mental connections are active neural connections.
To simplify, think of the way that conditioned learning works. A bell rings when the dog is presented with food. After a while, the same physiological response that the presentation of food results in occurs with the bell. There is "overlap" between how the brain represents the bell and food.
This is kind of the opposite of redundancy, which is why I'm not clear on what idav means by this.
That's probably a terrible explanation but usually it takes me several to get sufficiently non-technical and yet informative.
I don't know if it is a good explanation or not but I might not be getting it in either case. But then again, maybe I am. Because the only thing I could come up with in thinking about this was that a memory could be like a repeated neural pattern. So let's say "dog" has a specific neural signature in the brain. We could draw a diagram showing what neurons fired when we saw a dog and how they interconnected. So every time we see a dog the neural pattern is familiar to our conscious mind. It's the like the brain says "Oh yeah, I know this path. I've walked it before". When it is something new to us there is a different neural pattern that is established. But once that pattern has been established multiple times the same type of recognition occurs.
So the memory is not "stored" anywhere in anything analogous to how we think of things being stored. It's just a repetition of a familiar, recognizable pattern that has occurred before. The more that route is traversed the stronger, more durable the memory of it.
Is that anything close to what you are saying?