Are memories made of this or that?

[Graeme M]

Thanks Laroxe. I think my original question was in the form of a generalisation about the brain's architecture. When I wondered whether memories are copies of experience or regenerated representations of experience, I had in mind a particular architectural arrangement rather than any specific functional decomposition.

The paper I linked to above is to an extent reflecting the same general architectural issue. I thought it interesting and relevant in the context of the discussion.

The abstract says:
"We propose that the phenomenon known to neurologically intact people as ‘Subjective Experience’ is best understood as the activation of various sites in both extrinsic and intrinsic networks by a brand new episodic memory engram (i.e., a complex theta wave coding pattern originating from field CA1 of the hippocampus). Like a media news outlet, the hippocampal complex receives reportage from widely distributed structures around the brain and organizes and binds those reports together into a brand new episodic memory (i.e., a virtual-reality, movie-like, unified, contextualized, but vastly simplified summation of what just happened). This memory pattern is then ‘broadcast’ back to structures across the brain (via bidirectional pathways to and from the entorhinal cortex and perirhinal area) for error correction, to expedite predictive processing, and to inform sites in both extrinsic and intrinsic networks of one unified history. It is the cortical activation by the new episodic memory engram that gives rise to the event of experiencing. Because episodic memory is the only unified and contextualized representation of self-in-the-world in the brain, and because it informs most of the major cortices about ‘what just happened,’ it is subjectively misinterpreted as the actual interaction of the body/mind with its environment. This misinterpretation offers insight into many of the distinct and mysterious features of neurotypical subjective experience and the pathologies of consciousness".

 

[DiracPool]

When I wondered whether memories are copies of experience or regenerated representations of experience

What's the difference? I'm not sure what you're getting at. Memories are stored as Hebbian cell assemblies from a bottom-up process from sensory receptors through to cortical pathways, and these cell-assemblies are "re-triggered" in a top-down fashion in the reverse direction. The fidelity of the percept is never going to be as true from the re-ignited top-down recall as it is from the native bottom-up formation process, but the experience of each occupies the same neural anatomy. The main difference is that the top-down recall of a given sensory percept doesn't extend as far down the sensori-motor hierarchy as the bottom representation does, along with the fact that every stored Hebbian cell-assembly percept gets degraded over time as new experience plants superposed cell assemblies on previous representations of percepts which confound their fidelity during recall.

 

[Graeme M]

All I meant in that sentence is that my original question was to wonder whether a complete separate copy of the experience was stored as the memory - that is, two quite distinct neural structures. I simply didn't understand the process/mechanics involved. I think you explained all that well enough throughout the thread but that right there is an even better and more succinct version!

What do you think of the abstract I quoted above?

 

[DiracPool]

What do you think of the abstract I quoted above?

I know Bill Faw. He's a good guy. I think of him as the class clown of the consciousness community. He's written several reviews of the Tucson consciousness conferences that are very well considered. I always enjoy reading these because here is a person that truly has a love of our science and our field, enough so that he sits out the grueling week-long bi-annual Tucson conference and comments on essentially every presentation. That's devotion.

As far as the content of the abstract you posted, however, I'd be hesitant to consider his modelling too seriously. That is, we don't know how the CA1 region of the hippocampus relates to memory retrieval or storage other than speculation, his usage of phrases such as "episodic memory engram" harks back to nightmare L. Ron Hubbard 80's craziness. To be fair, though, the term "engram" is closely associated with the concept of the "Hebbian cell assembly," so they are actually qualitatively similar. However, using the term "engram" is an amateur move, which I'm suspect of.

Plus, the usage of terms like "episodic memory" are throwbacks, again, to 80's conceptions of how the brain stores and retrieves memories, along with concepts such a "working memory," etc. You'd be best off eschewing all that bull#$% and start reviewing current articles in more high-impact journals.

 

[mfb]

one is the "continuity" camp that think that human intellect is just a linear extension of all other primate intellect, descending down to even lesser mammals, and then there is the "discontinuity" camp that believes that the human brain is special and processes at least cognitive information fundamentally different from all other mammals. I happen to subscribe to the latter camp.

This seems to imply that there was some first human after the discontinuity - someone with intellectual capabilities completely different from those of their parents. Is that what you expect? If yes, what changed within this single generation?

 

[DiracPool]

This seems to imply that there was some first human after the discontinuity - someone with intellectual capabilities completely different from those of their parents. Is that what you expect? If yes, what changed within this single generation?

That's a great question mfb. What changed was a fundamental reversal in the direction of information flow in the highest or phylogentically most recent regions of the hominin neocortex. The details are somewhat involved but the basic bifurcative event was that, and it does mark a discontinuity in the cognitive evolution of primates. If you don't believe me, then you tell me why we can't talk to the animals.

If you promise not to blow my cover, I'll privately email you some of my more recent review articles.

Edit: let me qualify this a bit, it obviously didn't happen in one generation. However, from a geologic or phylogenetic perspective, it might as well have. The bifurcative event began with the appearance of Homo erectus around 1.8 mya and was largely consummated with Homo sapien down the road, but that's my personal speculation and not ready for prime time here.

 

[Graeme M]

I think it's intriguing that you suggest an evolutionary bifurcation that happened abruptly. Do you think capacity for language arose simultaneously or that the initial changes led to that capacity emerging? We could have all the cognitive function in the world but without language we aren't going to do a whole lot with it. Do you broadly agree with McNeil's work around the close association between gesture and spoken language? I gather from some of the reading I've done on that there is the suggestion that gestural patterns as encoded within motor cortex would have provided the basis for vocal events, though I confess much of that went over my head. I think McNeil argues more that both represent a synchronous functional unit that draws upon a common neural substrate but I may be misrepresenting his views. But perhaps that is consistent with your suggestion for a rapid evolutionary event?

I don't know if it was discussed here, but Ryabov recently published a paper that claimed dolphins to have language. I gather his ideas were met with considerable scepticism but dolphins are known to be able to learn artificial languages and understand abstract concepts. I haven't read his paper yet but hope to get around to it at some point.

http://www.sciencedirect.com/science/article/pii/S2405722316301177

 

[Graeme M]

Getting back to Faw's paper, the central idea though remains even if the underlying model or terminology is outdated. From what I've understood many researchers see consciousness arising first and then the memory of that experience being encoded by way of the hippocampus. Faw is suggesting that consciousness occurs simultaneously with memory formation - that consciousness IS memory. I don't mean to divert the discussion in that direction, I just thought it very interesting in light of what I came to understand memory to be as distinct from what I had thought of it being...

Oh, by the way. I like this! "You'd be best off eschewing all that bull#$% and start reviewing current articles in more high-impact journals."

 

[mfb]

then you tell me why we can't talk to the animals.

I'll do this directly after you tell me why no other species can communicate well with any other species*. If the discontinuity you expect would be the main obstacle then where is inter-species communication without humans?
We can talk to other species - just in very limited ways because other species are different. And as far as I know we do that better than any other inter-species communication (okay, we also try harder).

If something did not happen in one generation then there are intermediate steps. Enough steps and you can call it continuous (not in the mathematical sense, of course).* I know that some species can understand things like predator warnings of other species, but that is not advanced communication.

What I get in private stays private.

 

[DiracPool]

I'll do this directly after you tell me why no other species can communicate well with any other species*.

Other species communicate just fine with each other. Conspecific communication is robust, that's how they're able to mate and procreate. What no other animal has, though, is human-like spoken language or even gestural language. But human language if you want to look at it from a strictly communication perspective is unique in the animal kingdom in that it is characterized by having a hierarchical sequential structure. I mentioned this in posts #10 and #28 in this thread. This is important and it is what distinguishes us from non-human animals in a qualitatively discontinuous sense. It related to the extreme phylogenetic growth of the human prefrontal cortex and the hierarchical-sequential nature of the formation of motor behaviors that the prefrontal cortex performs. Human language production is hierarchical-sequential in nature, as well as mathematical ability and musical ability. Seeing as language, math, and musical abilities are qualities specifically associated with the human mind and combine with that the fact that the human brain has a huge motor cortex, the answer to the mystery as to what it was that happened to the human brain to give rise to unique human capacities doesn't seem to be such a complicated task.

If something did not happen in one generation then there are intermediate steps. Enough steps and you can call it continuous (not in the mathematical sense, of course).

There's never (or rarely) a sharp bifurcation that's going to happen in one or a few generations when it comes to natural selection, especially when it comes to something as momentous as human consciousness and cognition. I addressed this in the "Edit" portion of my post #41 in this thread.

 

[DiracPool]

I think it's intriguing that you suggest an evolutionary bifurcation that happened abruptly. Do you think capacity for language arose simultaneously or that the initial changes led to that capacity emerging?

One of the reasons I keep responding to this thread is that I think you are asking the right questions, Graeme. This tells me that you are thinking about the subject in an informed fashion. As far as your question I quoted above, I'd say, yes, what happened was that the gross increase in the size of the hominin frontal cortex reversed the direction of information flow in the hominin brain and then language, math, musical ability, logical thought, all of that fell out from that bifurcative reversal. It's a story of how brain regions confer dominance over others as far as their neurodynamics. The specifics are complicated but the general idea is very simple and straightforward. Of course, for the record, this is my personal model.

Do you broadly agree with McNeil's work around the close association between gesture and spoken language?

I'm too lazy to review that paper right now as I have been up for the past 24 hours crafting this paper for the deadline of the IJCNN-2017. If the paper gets accepted (which it will because I'm co-writing it with one of the conferences main organizers ), then I will be spending a week in Anchorage, Alaska in May. Woopie..

http://www.ijcnn.org/

I was really excited about visiting Alaska until I remembered Tony Montana's take on it...



I'll be sure to dress warm!

As far as your comment about the common substrate coming out of the motor cortex regions associated with Broca's area, the answer is yes, this is the general idea. There have been many speculations of this nature over the decades, and again, If I weren't so tired, I'd offer up some references. The problem with all of these models, at least the ones that I have read, however, is that none f them posit, again, a major bifurcative event as triggering the complex of uniquely human traits. This is where they missed it. I call this a kind of "reverse Darwinism." Right? For hundreds of years people held to the OBVIOUS view that there is something qualitatively unique about the mental capacities of the human species, but the whole thing got confounded because of the notion that there was a "god" that put a soul in humans. Then Darwin came along and said we're nothing but an average ape (DON"T make a monkey out of me!). Oh yeah, that sounds good. Sounds scientific. Now we can dump the whole god thing and be scientific about it. So, for the past 100 years everyone has been striving to demonstrate that we are just like every other monkey and that every other monkey is just like us. Right? This is the reaction against the human soul argument. But I think they overshot their mark and for the past 15 years I have argued with these people at academic conferences and still argue with them.

 

[john101]

Do non-brain cells remember.
Is the mind one of the senses.

 

[mfb]

Other species communicate just fine with each other. Conspecific communication is robust, that's how they're able to mate and procreate.

The topic was communication across species boundaries. If we cannot communicate with other species because we are a separate group: How well do other species communicate with other species in the same group as them? If that doesn't work either, how can you be sure the group boundary is an obstacle?

 

[DiracPool]

The topic was communication across species boundaries. If we cannot communicate with other species because we are a separate group: How well do other species communicate with other species in the same group as them? If that doesn't work either, how can you be sure the group boundary is an obstacle?

I'm not exactly sure what species/group boundaries you are referring to. The research I have done takes the position that human cognition utilizes a mechanism that is unique and distinct in the animal kingdom. Part of the manifestation of that mechanism is spoken and written human "language." So humans can communicate with one another through language not only because they have a language apparatus that allows them to produce human vocalizations, but principally because the human mind/brain has the cognitive apparatus to understand it. This is why we can't talk to the animals.

As far as the manner in which species other than humans communicate with each other, this is a complicated question but my point is that it is not qualitatively comparable to the manner in which humans communicate with each other, at least through the language mechanism. Non-verbal communication is another story. So, the bottom line is that we can't know how non-human species communicate with each nor how sophisticated that communication may be, other than to say that it is qualitatively distinct from human-specific communication that comes about through language. This line of thinking, which I largely ascribe to, is perhaps best associated with Macphail's "null hypothesis."

http://rstb.royalsocietypublishing.org/content/308/1135/37

 

[mfb]

This is why we can't talk to the animals.

Do you mean "this" as in "if animals would have the same, we could talk to them" or "if we wouldn't have that, we could talk to them"? I interpreted your earlier posts in the second way. If you mean it in the first way, I misunderstood your posts.

 

[john101]

further to my questions. two more.

What about pre-language or non-language memories. eg wolf-child. Infants. Deaf-mutes.

What is distinction between instincts and reactions. Both seem rooted in some kind of memory.

 

[Graeme M]

Mods, I am not sure if this is permissible so if not please delete.

Earlier I mentioned the paper by Matt and Bill Faw regarding the "hippocampal simulation" proposal as an explanation for both memory experiences and subjective consciousness. I really rather like their idea even though I cannot really critique it from a functional/physiological point of view. If anyone else is similarly intrigued but hasn't read the paper, this is an interesting introduction to the idea.