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Scientists monitored brains replaying memories in real time

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21–30 of 55 posts

Re: Scientists monitored brains replaying memories in real time

#21

How long until we see the headline “Summons allows court to monitor brains replaying memories in real time”

It will never be easy. This kind of tech will rely on the subjects thinking of that memory. And you can always, well, choose not to. Or even corrupt the memory deliberately by imagining things.

Re: Scientists monitored brains replaying memories in real time

#22
post #6

I’ve always wondered if there is a way to stimulate a brain so that you could replay a memory so vividly that it practically feels like you are there reliving it again, like the way you might experience a dream but with more clarity, almost like a form of time travel. I remember reading about some experiment in a psychology class where an old woman’s brain was probed and she was able to hear her highschool graduation…

https://www.ncbi.nlm.nih.gov/pubmed/22282432

Re: Scientists monitored brains replaying memories in real time

#23
post #21

How long until we see the headline “Summons allows court to monitor brains replaying memories in real time”

It will never be easy. This kind of tech will rely on the subjects thinking of that memory. And you can always, well, choose not to. Or even corrupt the memory deliberately by imagining things.

Isn't it very hard to "not think about it" when required to not think about it ?

Re: Scientists monitored brains replaying memories in real time

#24

How long until we see the headline “Summons allows court to monitor brains replaying memories in real time”

In the U.S constitutional complaint about right against self-incrimination. But if it worked well it would be too useful to let that right stand, so I'm sure the courts would decide it was not covered by the right.

Re: Scientists monitored brains replaying memories in real time

#25
post #21

Earlier quoted context omitted.

It will never be easy. This kind of tech will rely on the subjects thinking of that memory. And you can always, well, choose not to. Or even corrupt the memory deliberately by imagining things.

Isn't it very hard to "not think about it" when required to not think about it ?

It's a skill that you can practice through meditation. But false-memories and fabricated memories will shoot this idea down long before that stuff comes into play. Memory is no where near reliable enough to be used as evidence like that.

Re: Scientists monitored brains replaying memories in real time

#26
post #5

"NIH researchers found that our brains may store memories in neuronal firing patterns that are replayed fractions of a second before remembering." So it's like a phonograph record. First the track is inscribed from the source sound (storing a memory). Then the needle is placed in a groove (by some triggering experience). Then the needle traverses the inscription, playing back the recording (remembering). The brain ju…

To me, it much more closely resembles a key-value retrieval system. I wonder if we could learn anything about that by training an artificial neural net to perform key-value storage?

Machine Learning phd student here! I am currently working on a branch of ML called Continual Learning that deals with this theme exactly. It turns out Artificial Neural Networks have a hard time recalling things they they see in the past [1].

One of the most effective strategies to counter this issue is storing and periodically replaying old training items (i.e. “memories”) for the network [2]. There are also approaches that set out to mimic what we understand of the brain and adopt cue-based approaches [3], but they don’t seem to have reached meaningful outbreaks just yet...

[1] https://en.wikipedia.org/wiki/Catastrophic_interference [2] https://arxiv.org/abs/1902.10486 [3] https://arxiv.org/abs/1711.10563

Re: Scientists monitored brains replaying memories in real time

#27
post #5

"NIH researchers found that our brains may store memories in neuronal firing patterns that are replayed fractions of a second before remembering." So it's like a phonograph record. First the track is inscribed from the source sound (storing a memory). Then the needle is placed in a groove (by some triggering experience). Then the needle traverses the inscription, playing back the recording (remembering). The brain ju…

That said, unlike an old gramophone which has a pretty direct linkage the final sound-waves, I believe the hints/associations that are retrieved are then subject to an astonishing amount of inference and extrapolation.

We don't remember things so much as imagine them.

Re: Scientists monitored brains replaying memories in real time

#29
post #6

I’ve always wondered if there is a way to stimulate a brain so that you could replay a memory so vividly that it practically feels like you are there reliving it again, like the way you might experience a dream but with more clarity, almost like a form of time travel. I remember reading about some experiment in a psychology class where an old woman’s brain was probed and she was able to hear her highschool graduation…

You can achieve this clarity in a lucid dream... how accurate the memories relived would be, is another matter

Re: Scientists monitored brains replaying memories in real time

#30
post #5

"NIH researchers found that our brains may store memories in neuronal firing patterns that are replayed fractions of a second before remembering." So it's like a phonograph record. First the track is inscribed from the source sound (storing a memory). Then the needle is placed in a groove (by some triggering experience). Then the needle traverses the inscription, playing back the recording (remembering). The brain ju…

The much more magical part to me is how firing these patterns of electrical activity gives rise to an experience of remembering...

Also, how exactly do they know the neuronal firing patterns happen before remembering? If you have to signal you remembered something (as in the article, a word pair), isn't there always a delay between the experience of remembering and signalling your recall? Isn't it more accurate to say the electrical signals are fired fractions of a second before communicating what you recalled? How to know if what you remember doesn't correspond 1-1 with the neuronal firing patterns taking place (or even before the electrical activity).

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