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Human brain compresses working memories into low-res ‘summaries’

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Re: Human brain compresses working memories into low-res ‘summaries’

#2
> It turned out that either visual stimulus—the grating or moving dots—resulted in the same patterns of neural activity in the visual cortex and parietal cortex. The parietal cortex is a part of the brain used in memory processing and storage.

> These two distinct visual memories carrying the same relevant information seemed to have been recoded into a shared abstract memory format. As a result, the pattern of brain activity trained to recall motion direction was indistinguishable from that trained to recall the grating orientation.

Isn't the alternative explanation that our tooling for inspecting the brain at work abstracts too much detail away for us to be able to tell the difference?

Re: Human brain compresses working memories into low-res ‘summaries’

#4
It all works this way (though a certain female family member would disagree, claiming to remember conversations word-for-word years later).

But my memory works this way. A summary "party at so-and-so's house, weather was nice, overall vibe was ___". The rest is context. You know what the house/backyard is like, you know the general feel of that time of year, you know the crowd that usually comes, you can easily synthesize details like the smell of the BBQ and the taste of the food... build up a complete "memory" from stuff that could be summarized in a paragraph of text plus generic (not specific to one memory episode) context.

I can build up a relatively vivid mental image of my walking route to school (from the bus terminal) over 40 years ago. Is it accurate? Who cares. As long as no detailed record exists to compare it to that would reveal the "lossy compression".

Re: Human brain compresses working memories into low-res ‘summaries’

#5
This is nothing new; I have read several books and works on neurology, and this is best described a "a simplified representation of the environment". Thanks to signal noise and neuroplasticity over time the weakest connection points between "remembered" stimuli deteriorate and all what is left is even more simplified version of a "memory". I am surprised that they did not heard of it yet.

Re: Human brain compresses working memories into low-res ‘summaries’

#6
post #5

This is nothing new; I have read several books and works on neurology, and this is best described a "a simplified representation of the environment". Thanks to signal noise and neuroplasticity over time the weakest connection points between "remembered" stimuli deteriorate and all what is left is even more simplified version of a "memory". I am surprised that they did not heard of it yet.

That doesn't sound like quite the same thing. This finding seems to suggest that the memories are compressed from the get-go. Where you are describing why memories get more compressed over time, I think.

Re: Human brain compresses working memories into low-res ‘summaries’

#7
post #2

> It turned out that either visual stimulus—the grating or moving dots—resulted in the same patterns of neural activity in the visual cortex and parietal cortex. The parietal cortex is a part of the brain used in memory processing and storage. > These two distinct visual memories carrying the same relevant information seemed to have been recoded into a shared abstract memory format. As a result, the pattern of brain…

Indeed, it's like saying "the CPU used 16 Wh of energy, executed 1 billion MOV instructions and 2 billion ADD instructions for both these two tasks, thus the algorithm it ran must be identical".

Re: Human brain compresses working memories into low-res ‘summaries’

#8
As someone suffering from Aphantasia [0] (I don't have mental imagery at all) and I've been telling people for the longest time that this is how I relate to the world. I summarize things. Even my mother's face. A post by a Facebook engineer [1] felt like a good way to understand it.

[0] https://en.wikipedia.org/wiki/Aphantasia

[1] https://medicine.exeter.ac.uk/media/universityofexeter/medic...

Re: Human brain compresses working memories into low-res ‘summaries’

#10
post #5

This is nothing new; I have read several books and works on neurology, and this is best described a "a simplified representation of the environment". Thanks to signal noise and neuroplasticity over time the weakest connection points between "remembered" stimuli deteriorate and all what is left is even more simplified version of a "memory". I am surprised that they did not heard of it yet.

That doesn't sound like quite the same thing. This finding seems to suggest that the memories are compressed from the get-go. Where you are describing why memories get more compressed over time, I think.

The compression already begins with the receptors, maybe I should have started there. Each stimuli/pattern gets more simplified with each neuron layer, e.g. if a region of receptors fire a the same time, fire that one neuron, if not at the same time, inhibit that neuron, if nothing happens, do nothing. It's impossible to "capture" stimuli without compression with neurons in the first place. Information is being "reduced" or encoded if you will along the signal path into the brain, and then over time when recalling this information.
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