What *is* memory?

Factual Questions
1

What exactly is memory? We seem to run to engineer types around here, not medical types, but does anyone understand the chemistry of memory enough to dumb it down for the rest of us?

I say: “Your first girlfriend/boyfriend.”

You immediately think of think of a face, a name, and maybe the warmest moment you had/how you’d like to pour sugar in their gas tank.

The point being, somewhere, that information was waiting in your brain just waiting to be accessed.

So… What is the molecule that contains the information that constitutes a memory? I find it amazing to think that when I learn something or have a new experience, that I make a new molecule in my brain that actually will remind the concious part of my brain of something that happened in the past. And yet, obviously it does, some way. Even beetles can be trained, so it’s working on even very low life forms. Training involves having the brain of the trainee contain the information needed for the action to quick-n-easy retrieval.

Any nowlege out dere?

2

…i used to know the answer, but…

3

I don’t think anybody really can answer your question. I just finished reading John Horgan’s The Undiscovered Mind, and the impression I got out of that is that none of these “experts” really knows what the hell is going on in the human mind – including memory.

4

David B is right - nobody really knows, or even has much evidence as to what’s going on. On the other hand, there’s pretty wide (but not universal) agreement that memory isn’t just some kind of direct chemical coding, like the coding in DNA that specifies proteins. That’s unfortunate, in a way; it would be nice if we could synthesize and inject things like English history or calculus.

Possibly the most popular idea is that memory has something to do with varying the strength of the synapses between neurons, so that a stimulus of some kind somehow switches on whatever set of neurons correspond to the state of consciousness that we call ‘remembering’. Notice how vague that is? Think a psychologist or neurologist could make it more precise? Yeah, right.

Bob the Random Expert
“If we don’t have the answer, we’ll make one up.”

5

Well, I think the “engineer types” these days have a lot better understanding of memory than the “medical types” do.

I would put myself closest to the android209 type:

As for the David B types, I can find no types more disgusting in their thinking than those who come up with this sort of thing:

OK, so I don’t think anyone else is as presumptuous as David B. Who the hell cares what David B doesn’t think. . .or even what he does think.

And I hate how some people – e.g., rjk – feel they have to cater to the David Bs of the world:

, who insist it is holier to think only subjectively, even though this gain one no functional understanding. But then rjk goes on to divulge that he really has at least some objective understanding of human/animal memory.

Amnesia and forgetting are the complement of memory. So see the earlier thread:

. . . .“Why Do We Forget?”

People used to say, all the time, “We know how to use electricity but we don’t know what it is.” I suppose we must’ve learned somewhere along the line, because I don’t hear this statement these days. . .huh? The fact is, we always know a certain amount about any given thing, and what we know is really only constructs that help us “use” or relate to that thing, and there is always more we can learn about it (learn how to further use or relate to it).

The objective understanding of memory, for practical purposes today involves a degree of understanding of neural-network and synapse theory and empirics, along with molecular electrochemistry and such specialized suborgans of the brain as the hippocampus. Not many MDs understand much of any that, if for no other reasons than that it normally involves a lot of mathematics. The David Bs aren’t interested in much of anything that is not merely subjective wondering in their own brains, and so they then claim nobody else knows what they don’t and wouldn’t touch.

There are numerous references, in the above-linked earlier thread, to Web pages that cover a certain amount of the abovementioned objective knowledge. If you just want to wallow in subjective stuff, then:

. . . .“Memories are made of this.” Don’t forget it!

Ray (I’ve forgotten more than I remember – of this subject, as well as of all the others.)

6

Since I don’t much like being scorned, or flamed if that’s what it’s intended as, I’ll just try not to remember that.

Bob the Random Expert
“If we don’t have the answer, we’ll make one up.”

7

Dear Mr. Nanobyte,
I’m not sure the gratuitous personal attacks contained in your latest post contribute anything to our gentle reader’s understanding of the subject at hand or do anything to enhance your personal credibility.

Please modify your style to leave out your personal opinions of the scope and quality of other member’s cognitive processes and/or direct such superfluous comments to the BBQ pit forum.

Nickrz
GQ Mod for the Straight Dope

8

Nanobyte said:

Funny. I’m an engineer type and you didn’t seem to have a whole lot of respect for what I said…

Really? You find it disgusting to admit that we don’t know? You’d rather what – that I make up an answer?

Yeah! How dare he agree with me?! He ought to be hanged from the nearest tree!

Gosh, that’s great. But we’re not at that point today with memory or the human mind in general. Maybe someday we will be (I expect that at some point we will, I just don’t know when), but we’re not there yet.

It’s all very well and good to throw around a bunch of technical terms, but you haven’t actually explained anything.

ROFL! Man, do you realize how silly you look? You obviously know nothing about me, but have chosen to leap to an illogical conclusion based on one message, and act like you now know everything about me. ROFL again!

I would suggest that, before you post again about me, you continue your search for a clue.

9

Whoo boy. I can see this thread is going nowhere fast.

Let’s limit our recitations to theories of the actual mechanics of memory, please, lest this thread become a distant one.

10

Asking what chemical or what physical crease equals “where I was on the evening of June 16” or “how you calculate the square root of a number without a calculator” is like asking which pin on my RAM DIMM chip contains Microsoft Excel. In other words, the hardware of the brain seems to be a mechanism for perpetuating a dynamic environment of synaptic firings and they maintain memory, attitudes, behavior, balance, etc.

Electrical stimulation of specific areas in the brain will trigger specific memories in an individual person (specific to that individual person, though). However, there is absolutely no reason to believe that removing a core sample of that area of the brain and transplanting it into someone else’s brain will allow the recipient to acquire the donor’s memories or knowledge.

Designated Optional Signature at Bottom of Post

11

When I was studying the neurophysiological basis of learning and memory, admittedly about 10 years ago now, there was a great deal of research being done into how exactly memories are formed, what diffferentiates long term and short term memories, how quickly do these process’ degrade, that sort of thing. I remember two things, firstly that it was really really complicated stuff if you weren’t good at chemistry, physics and anatomy, and secondly they were very far away indeed from finding out about specific memoris. Studies were mainly on aplysia californicus, a really boring aquatic snail with the good fortune to have a very simple “cortex”, and finding out what changed when memories were formed. They were still very far away from being able to connect these changes with any cognitive “sensation”. A parallel with human beings would be knowing roughly in which part of the brain all your memories of youth were stored but still being very far away from pinpointing where exactly your memory of that afternoon at the circus was kept. The main source of data on humans comes from the 1st World War when doctors indirectly gathered neurological data from patients in the trenches who had sustained head wounds and were either being fixed up or beyond salvation. This data was more anecdotal in nature, for example a patient would tell a doctor that when a certain part of the brain was touched he could smell lavender, or something of the sort. None of this research, neither then or now, “…normally involves a lot of mathematics.”

12

Ray,

Holy Cow, you’re in a bad mood. I hate to get involved in flame wars, so I won’t… however I would like to gain some clarification on what you’ve said. You made it sound quite authoritative, yet completely unfulfilling…

You wrote:

Well, duh. That’s a bit like saying that automechanics involves a degree of understanding of metallurgy and plastics, along with petrolchemistry and such specialized sub mechanisms of the engine as the carburetor…

What you fail to note (or perhaps realize) is that we still don’t know how these electrochemical processes that you mention interplay with the aforementioned nerual networks or hippocampus to create that phenomenon we know as memory.

… which is, I believe, really what our fearless moderator David B said. Sure we have some clues and have made some interesting observations over the years, but we are a long way from having a comprehensive understanding.
By-the-way, I checked out several of the links that you referred to and noticed a couple of problems.

(1) The page on the hippocampus seems to be ignorant of more recent findings about the hippocampus role in memory. Perhaps it is out of date, or perhaps the authors have elected to ignore findings that are inconsistent with their theories. Recent studies have shown that new memories can be committed to long term memory without passing through the hippocampus… which pretty much destroys earlier theories that the hippocampus was the gateway to long term memory.

and

(2) Most disturbing… You’re still pushing references to Artificial Neural Networks in support of your arguments about the human brain… I’m experiencing Veja Doo… the feeling that I’ve stepped in this crap before. ANNs are not accurate models of the human brain.

13

AH3 and Joey, those are both good examples of what seems to really be going on.

I’ll expand a bit on what seems to be the biggest promblem for understanding memory: we’re working on three different levels (at least), and have some knowledge of each level, but no substantial idea about how they connect.

The three levels I see are:
[list]
[li]Psychological - consciousness, behavior and memory[/li][li]Anatomical - brain structure, EEGs and PET scans[/li][li]Neural - cell cultures and biochemistry[/li]
The links we have between levels are pretty obscure. We can say that vision, for example, is associated with certain brain areas, but don’t really know how seeing something turns on those areas. Similarly, we remember seeing something, and it pretty certainly has something to do with varying the strength of synapses, but we don’t know what makes them change in that particular way.

Bob the Random Expert
“If we don’t have the answer, we’ll make one up.”