Hacker News Reader

Comment by Karlozkiller | Hacker News Reader

Things like memories are not well understood from what I've gathered as a Master's Student in cognitive science.

I mean, it is thought to be stored in the form of persistent patterns in neurons and we know certain areas of the brain that are vital for the formation of memories. But there is no clear model of how memories are formed.

There has been rapid increase in understanding of such things lately and I would say neural networks give some insight and ways to explore and experiment with different configurations further.

A physical model like this could probably serve as a proof of concept and maybe help further knowledge in the are, but I suspect computerized simulations will serve this purpose better.

tldr; as much of a layman I believe we know too little about the brain to make a proper physical brain.

View on HN

Overall, you are right in your diagnosis - we simply have not located a single mechanism responsible for memory. In reality, it is probably a collective effect due to a huge maelstrom of chemical computing. Our brain is one of the most imposing dynamical systems ever studied! That's why the mathematics and in turn modeling of it is so beastly.

Right now there are broadly speaking two camps in neuroscience, those who are connectionists and believe that memories are overall rather non-volatile/physically localized, with an MIT group that showed particular (individual ) neurons linked to particular memories, at the extreme of that school. On the other hand, you have neuroscientists who subscribe to a more plastic conception- in which mass synchronizations and redundant information is consistently combined and recombined.

My take is that it is no contradiction to admit the our brain is clearly volatile, and non-volatile in different modes. The transition from STP (short term memory) to LTP (long term memory) probably involves different conformational changes in neurons, dendrites, who knows even on the epigentic scale. But we do know the volatility is important and interesting-- which is precisely what makes this diffusive memristive study so important!

I saw pictures labeled extracted from live brain scans. How that was done I don't know, maybe alpha or beta waves. At least that's short term memory.

Brain scans are not as accurate as one might think. Most or all methods merely show activation of neurons or groups of neurons over a timescale.

Typically you give a person, say a memory task, you look at which areas fire up as he tries to memorise a word list and from that you extrapolate whatever you can from it. I also believe working memory and short term memory are to some extent better understood than long term memory. actually the least known process regarding memory I think is how memories pass from working memory or short term memory into long term memory.

I didn't express clearly. They scanned the brain and recreated some part of what the person sees.

1. http://news.berkeley.edu/2011/09/22/brain-movies/

2. http://gallantlab.org/_downloads/2011a.Nishimoto.etal.pdf

Spoilers: It is fMRI, indeed.

I'm not sure if the scan is inaccurate or the representation within the brain, but I suppose it had to be more accurate than just a fuzzy area.

Reply on news.ycombinator.com