Thank you all very much for your comments and links. I would also like to offer my sincere apologies for the long delay in my response to you all. Truth be told, I’ve been busy proof-reading a text on optics which is in the process of being translated into English, so I haven’t had much spare time recently.

After reading all your comments, I have to acknowledge that Braude’s original argument that memories cannot possibly be stored in the brain, which I cited above in #13 and #23, is by no means as compelling as I had imagined, although I still think it has a good deal of merit, for reasons I shall outline below.

Scrofulous’ suggestion (#24) that memories stored in the brain may be content-addressable certainly makes a lot of sense, and I think it’s a satisfactory response to Braude’s infinite regress argument.

By the way, here’s an interesting link: A Hybrid Neural Network of Addressable and Content-Addressable Memory by Kinwen Ma in International Journal of Neural Systems, Vol. 13, No. 3 (2003) 205–213.

See also “A DNA Associative Memory Potentially Larger Than The Brain” by Eric Baum in DNA Based Computers edited by Richard Lipton and Eric Baum (Proceedings of a DIMACS Workshop, April 4, 1995) at http://books.google.com/books?.....38;f=false .

I will also take on board Mr. Nakashima’s point that computers can be said to check their own memories, using algorithms such as checksum, and can also recover them. However, it would be a category mistake to attribute the cognitive attitude of skepticism to a computer purely on the basis of its ability to detect and correct its own faults – and I don’t think you would wish to do that, anyway.

Seversky makes the excellent point that difficult as it is to suppose that memories are stored in the brain, our problems are multiplied many times over if we suppose them to be stored somewhere else – e.g. in some immaterial realm. I agree – and so does Braude . That was his whole point – memory isn’t stored anywhere:

However, it’s one thing to say that the brain mediates the capacity to remember, and another to say it stores memories. The former view (more likely the correct one) takes the brain to be an instrument involved in the expression of memory; the latter view turns out to be deeply unintelligible. For a very limited analogy, we can say that while a functionally intact instrument may be causally necessary for performing a musical improvisation, the music is not stored in the instrument (or anywhere else).

What Braude was trying to do was shake off the old trace paradigm which has dominated Western thinking about memory for 2,400 years – just like Plato’s Theaetetus account of knowledge as justified true belief, which was widely accepted until Gettier challenged it. What if the trace is a scientific blind alley? What if it’s a stale idea that no-one has challenged, simply because we can’t imagine the alternative?

Seversky also objects that everything else that remembers, does so by storing data, so it’s a fair bet that our brains do the same:

For memory to work, however it is encoded, the data must be retrievable in the same form as it was entered. Every form of long-term storage of data we have now … involves recording it on some sort of physical substrate which does not change over time or, rather, does so very slowly.

To my mind, all this argument proves is that if you’re going to store a memory, you’d better store it somewhere safe and stable, over time. Yes – if. And in any case, we know that the brain isn’t like the examples Seversky cites. Whatever human memory is like, it certainly isn’t like “symbols chiseled in stone or clay, inkmarks on parchment or paper, spiral grooves on a disk.” There are no stone tablets in the brain, that’s for sure.

Let’s go back to the other arguments raised by Braude against the storage theory. I would like to point out that even if we grant that human memory is content addressable, severe epistemic problems relating to memory still need to be addressed.

All of you seem to have agreed (or conceded) that if memories are stored in the brain, they are not isomorphic to the events that they are supposed to be memories of.

In that case, it seems we may still legitimately ask:

(1) What makes them representational, if isomorphism is absent?

(2) What makes them memories of one particular event in the past, rather than a host of similar events resembling it, which might have happened instead?

(3) Why should we trust them, if there is no guarantee of their accuracy?

(4) How far should we trust them, if there is no such guarantee?

Now, I will admit up-front that I don’t have a better theory of memory to offer you, so you could throw the same questions at me if you liked.

Mark Frank (#32) questions the legitimacy of Sutton’s request (see #23 above) for an account of how memories can uniquely specify past events, and for a guarantee of their accuracy, on the grounds that we all know memories are often faulty – i.e. partial and inaccurate. True – but we nevertheless rely heavily on them, in court, at work and in everyday life. I would argue that that degree of trust requires a warrant of some sort – and at present there is none. Mark Frank’s answer to the warrant problem is a practical one:

Because in practice we find that they are mostly reasonably accurate as determined by consistency with our other memories, other people’s memories, and current observations.

I have to say that this sounds a lot like the coherence theory of truth (an account which fails to give us the truth), with an added evolutionary twist. For I presume Mark Frank would add that if our memories weren’t generally reliable, we wouldn’t be here now. Animals that mis-remember tend to die young, leaving no progeny.

Well, my response is: it’s not that simple. Showing that our memories work and have worked in our evolutionary past isn’t the same as showing why we should trust them. I might have a justified belief that my memory is probably accurate at any given time. But the causal and structural nexus between a memory M and the event E that it’s supposed to be a memory of, remains as mysterious as ever. In effect, the pragmatic justification amounts to saying: “Don’t ask me how it works. It just does, that’s all.”

Will content addressable memory get us out of trouble? Scrofulous (#24) characterises it as follows:

…[A]n input pattern is presented to all of the memory locations at once. A particular memory location will activate itself based on how closely its contents match the input pattern.

While human memory clearly has much more in common with content addressable memory than with other kinds of computer memory, it behooves us to be skeptical. Where’s the pattern in the brain? That’s the point at issue. And if it does exist, it’s in flux. Sure, there may be a causal chain from the original event to the current memory – but causal chains can sometimes be wayward. (See http://www.blackwellreference......9524_ss1-3 .) It seems that a purely physicalist account of memory offers no way in principle of distinguishing a bona fide causal chain from a wayward causal chain.

Finally, the philosophical problem of how memories stored in the brain could be said to be representations has not been addressed at all.

Graham1, I don’t wish to deny for a moment that brain damage often destroys people’s memories and abilities, and also changes people’s personalities drastically. But what I would predict is that if scientists could somehow repair the damaged brain – e.g. undo a lobotomy or grow back a prefrontal lobe – the ability or memory should reappear. If the storage model is correct, then it shouldn’t: even if the damaged part of the brain grows back, the old pattern in the brain that constituted the memory will have gone forever.

Now that would be an exciting empirical test.

Bornagain77, thank you very much for the links to the articles about Dr. John Eccles and also the article by Dr. Michael Egnor. They were well worth reading.

Sorry to come late to your comment, but I think if we can analogize to computer memory at all, then there are analogs to epistimology in the computer arena. One is the checksum, which is used to verufy that a number of memory cells have not changed. The error correcting code is similar. At another level of analogy, we have the database journal.

When these are combined, we have systems that know when they have suffered a ‘stroke’, such as a cosmic ray changing the values stored in memory, and a way of recovering the correct version of that memory.

We also have systems of reasoning that can explain their conclusions going back to ground facts such as “I observed it.” “I was taught it.” “I deduced it through this logical operation.”

How can we possibly store data, or perform processes in thin air ? Where is our ‘mind’ ? Does it follow us round like a cloud ? What happens when we die ?, does the cloud sort of drift away ?

Some evidence is needed please.

I thought the story of Phineas Gage (and many like it), should have demonstrated pretty clearly that physical changes to our brain cause changes to our entire nature. This is called evidence.

This is the most interesting exchange that I have seen on UD for months, possibly ever.

I take back my rather glib comment about Braude’s status. There clearly are interesting issues here.

Let me start by saying that I don’t think “memory trace” means a single physical configuration corresponding to each memory. Indeed I am not sure what “a memory” is. How do you enumerate memories? I agree with Sutton (and modern cognitive psychology) that remembering is a wide diversity of related but different processes which are constructive and dynamic. All I would contend is that there is no reason why memory cannot be an entirely physical process (and any apparent logical problems are not solved by adding a non-physical element).

You identify two key problems with memory traces:

(1) They cannot uniquely specify past events
(2) There is no guarantee of their accuracy

Again I concur with Sutton. I see no reason why they need to do either. We know all too well that in practice memories are partial and often inaccurate.

You ask why should we trust them? This seems rather easy to answer. Because in practice we find that they are mostly reasonably accurate as determined by consistency with our other memories, other people’s memories, and current observations. But in any case there seems to be no reason why adding a dash of the supernatural should make them more trustworthy.

A slightly different question is why do we trust our memories? This is different from why should we trust them. When I remember going to the cinema last night it is not based on a careful evaluation of its consistency with other events. I am certain because I remember it so vividly. There is also the phenomenon of recognition. I may be sure I have seen a face or situation before without knowing when or where (and this process may also be in error sometimes – déjà vu). This strikes me as an evolved facet of the way our mind/brain works. As in many other areas we have evolved a propensity to trust our senses and memories without stopping to evaluate them.

The computer example is helpful for two reasons. Although clearly far simpler than the human case it demonstrates two things:
1) How a physical trace memory can be linked to past event without causing an infinite regress

2) How a physical trace memory can “represent” a past event in the sense of allowing aspects of it to be reproduced without looking anything like the past event

As far as I can see the only objections you have raised to the computer example are:

Computers don’t ask sceptical questions and computers do a lot less with their memory. I don’t see the relevance of either to the two points I am making. Are you saying the objections to trace memories only apply to entities that can ask sceptical questions have complex memories? What about 1 year old children?

Finally let’s deal with non-episodic memory. Remembering is many different things and these different things may have different physical explanations. Semantic memory is broadly the ability to use certain facts (e.g. that the ipconfig command will give me the IP address of a router) in a wide variety of situations. The physical explanation is that there is something in our brain that causes me to reconstruct that fact when I need to. I see no reason why it has to correspond to a past experience – although clearly past experiences have created this ability in my brain. Indeed this is what learning in the cognitive brain is all about.
That’s quite enough.

angryoldfatman,

I suspect Seversky is talking about Elliot, a famous patient of Antonio Damasio’s who is discussed in this article by Jonah Lehrer.

Thanks, scrofulous, that’s the one.

In conjunction with the mathematical necessity of an “Uncaused Cause” to explain the beginning of the universe, in philosophy it has been shown that,,,

“The ‘First Mover’ is necessary for change occurring at each moment.”
Michael Egnor – Aquinas’ First Way
http://www.evolutionnews.org/2......html#more

I find this centuries old philosophical argument, for the necessity of a “First Mover” accounting for change occurring at each moment, to be validated by quantum mechanics. This is since the possibility for the universe to be considered a “closed system” of cause and effect is removed with the refutation of the “hidden variable” argument. i.e. There must be a sufficient transcendent cause (God/First Mover) to explain the quantum wave collapse to the “uncertain” 3D effect for “each moment” of the universe.

Why, who makes much of a miracle? As to me, I know of nothing else but miracles, Whether I walk the streets of Manhattan,
Or dart my sight over the roofs of houses toward the sky,,,
Walt Whitman – Miracles

Moreover, the transcendent cause must be sufficient to explain the semi-unique effect of 3D centrality witnessed by each individual observer in the universe.

Quantum Mechanics – The Limited Role Of The Observer – Michael Strauss – video
http://www.youtube.com/watch?v=elg83xUZZBs

That the “mind” of a individual observer would play such an integral yet not complete “closed system role”, in the instantaneous quantum wave collapse of the universe to “3D centrality”, gives us clear evidence that our “mind” is a unique entity. A unique entity with a superior quality of existence when compared to the “uncertain 3D particles” of the “material” universe. This is clear evidence for the existence of the “higher dimensional soul” of man that supersedes any “material basis” that the soul has been purported to “emerge” from. These following studies confirm this “superior quality” of our minds:

i.e. what right do we have to presuppose material to have the ability to produce a “mind” when a mind is shown to be necessary for “uncertain” 3D reality to “materialize from its quantum wave function in the first place? Clearly it is logically inconsistent to presuppose as such.

The Mind and Materialist Superstition – Six “conditions of mind” that are irreconcilable with materialism:
http://www.evolutionnews.org/2.....super.html

A Reply to Shermer – Medical Evidence For NDEs – Pim van Lommel M.D.
Excerpt: as soon as the function of brain has been lost, like in clinical death or in brain death, with iso-electricity on the EEG, memories and consciousness do still exist, but the reception ability is lost. People can experience their consciousness outside their body, with the possibility of perception out and above their body, with identity, and with heightened awareness, attention, well-structured thought processes, memories and emotions. And they also can experience their consciousness in a dimension where past, present and future exist at the same moment, without time and space, and can be experienced as soon as attention has been directed to it (life review and preview), and even sometimes they come in contact with the “fields of consciousness” of deceased relatives. And later they can experience their conscious return into their body.
http://www.nderf.org/vonlommel.....sponse.htm

in further note:

The Brain is Non-Materialistic In Its Organizational Structure thus strongly suggesting the brain is designed by a “living transcendent Being” instead of an accident of the random actions of “dead material particles” of which life supposedly accidentally emerged from:

Brain Innately Separates Living And Non-living Objects For Processing
http://www.sciencedaily.com/re.....142430.htm

Category-Specific Organization in the Human Brain Does Not Require Visual Experience:
Distinct regions within the ventral visual pathway show neural specialization for nonliving and living stimuli (e.g., tools, houses versus animals, faces). The causes of these category preferences are widely debated.
http://www.citeulike.org/user/.....le/5443232

The preceding fact is a very curious thing to know when seeing how people react to statements about the “Living” God:

To The Brain, God Is Just Another Guy
Grafman says there were some differences between religious and nonreligious people. Those who said they believed in God had a negative emotional response to statements like, “There is no higher purpose.” Nonbelievers had the same reaction to statements that assumed God exists.
http://current.com/items/89919.....er-guy.htm

In The Wonder Of Being Human: Our Brain and Our Mind, Eccles and Robinson discussed the research of three groups of scientists (Robert Porter and Cobie Brinkman, Nils Lassen and Per Roland, and Hans Kornhuber and Luder Deeke), all of whom produced startling and undeniable evidence that a “mental intention” preceded an actual neuronal firing – thereby establishing that the mind is not the same thing as the brain, but is a separate entity altogether. http://books.google.com/books?.....8;lpg=PT28

My immediate response was that his strongest argument was really based in the hard problem of consciousness. The mechanics of how we store and retrieve memories is obviously difficult in itself but not as difficult as explaining who or what is doing the retrieving.

Thinking about the question of whether or not memories are stored locally in the brain reminded me of the case of a British musician who lost the ability to store long-term memories following an illness. My own unreliable memory failed me when I tried to retrieve the name so I had to augment it with the Google search engine and eventually found Clive Wearing. I think his case is powerful evidence for memory being strongly correlated with the physical brain and that, to a large extent, we are what we remember.

If we assume the alternative, that memory is not stored locally in the brain but elsewhere, with the brain being some sort of interface device or transceiver, the problems are multiplied. Not only does the problem of explaining how memory works remain but also have to explain where and in what form memories are stored. If it is some kind of transcendental common mass storage domain, how do we locate and retrieve just our memories from all the others? Whatever the problems inherent in any explanation of brain-based storage, they are multiplied massively with such an alternative.

For memory to work, however it is encoded, the data must be retrievable in the same form as it was entered. Every form of long-term storage of data we have now – be it symbols chiseled in stone or clay, inkmarks on parchment or paper, spiral grooves on a disk, magnetic coatings on a tape or disk or pits cut in a disk by laser – involves recording it on some sort of physical substrate which does not change over time or, rather, does so very slowly. While allowing that science and technology could change dramatically in the future, there seems to be no escape from that principle.

While there is no reason not to explore more speculative approaches, it is reasonable to infer from the above that our memories are most likely stored in the brain.

It seems there is still a long way to go explaining how and we have yet to crack the hard problem of consciousness but cases like that of Clive Wearing and others, all the data from other disorders or injuries to the brain, research into transcranial electromagnetic stimulation and even Michael Persinger’s “God helmet” point towards consciousness and the mind being brain-based.

I suspect Seversky is talking about Elliot, a famous patient of Antonio Damasio’s who is discussed in this article by Jonah Lehrer.

In any case, there are hundreds of stories of patients whose emotion, will, self-knowledge, and even morality are affected by physical changes in the brain. The thesis that the mind is physical doesn’t stand or fall on the basis of Phineas Gage’s story.

And whatever “traces” do reside in the brain carry no assurance of their reliability, even in general terms. If that’s not a problem for materialism, I don’t know what is.

Why is that a problem for materialism? We know that memory is unreliable (cf. the work of Elizabeth Loftus on eyewitness testimony).

And if it’s a problem for materialism, it’s also a problem for those who believe in an immaterial mind, because you have no assurance that an immaterial mind is reliable, either.

The reliability (or lack thereof) of mind is something that must be ascertained from the inside, regardless of whether the mind is material or immaterial.