richard@sci.ccny.cuny.edu (Richard Hogen) (06/29/90)
I'd like to know what you pro's think about my 'theory' of the way memory works and how it explains DREAMS and DEJA VU. I am a Planetary Science student but my interests are broad, which is how I justify my right to have a 'theory' on brain function. That said... I don't really know what the current working theories are, but I do know that the common folk still think of memory as merely the dropping of "info" into "memory banks" which can be accessed. I suppose the logical extension is that certain neurons are designated as "memory neurons", taking on the job of organizing their 'signals' in such a way which uniquely describes the memory to be stored. This has never been a satisfactory description to me, primarily because it seems so incredibly inefficient and it's difficult for me to see how a more efficient method would not prevail on an evolutionary scale. The rest of this article is an attempt to describe a plausible, more efficient method which also helps me understand dreams and deja vu, two previously vague phenomena (IMHO). I. Vectors vs Packets Rather than seeing memory as discrete packets, ALL stored from early fetal stages on, I see memory as a layering of vectors or pointers. The process of inserting, rearranging or simply following the vectors is neuro- biochemically defined and internally consistent (amateur arm-waving). At the core levels, the fundamental vectors are simply a record of sensory input as the senses develop and begin to acquire signals; thereafter, memory vectors are akin to human tool-use. We build tools to build tools to build better tools and so on, but we don't have to rebuild every tool that we used from the very start in order to make, say, a radio. In this respect, technology can be thought of as an implicit memory system. One can imagine a population of humans all given amnesia. With simple control systems, these people would be able to operate the various machines it takes to make a certain item, but they would not HAVE to understand everything that went into the construction of the devices they are using. In this way, memory builds "interpretation forms" (IFs) if you will, which later levels of complexity use to build more complex IFs, and so on, so that a memory need only be a pointer to an IF in the next lower level of complexity which points to an IF in the next lower level...etc. Not everything is "stored" in packets, but the memory can be "reconstructed" by following the pointer paths backward. The act of "recalling" is a measure of one's skill and experience in the following of these pointer paths. I describe it in a linear fashion, but I see no consistency problem with imagining a memory requiring several IFs which point to several IFs etc. It can easily be seen, also, why certain people can be more visually- oriented: their interpretation form structure is broader and more complex when it comes to visual sensory data and associations, but deficient with respect to other sensory areas. It can also be seen that fundamental perspective changes might require reorganization of many levels of an IF structure, but in the process provide more satisfactory assumptions upon which an individual creates his/her world. One can even understand the sensation of frustration as new experience is assimilated into an IF structure which has no satisfactory end-member. II. Input Buffer => Max Capacity Often students talk of "overload" or some such - describing a state in which their minds can not store new information until after a period of rest and settling. To many people it is an accepted phenomenon, even though they may be at a loss to explain it. It seems to me that our level of activity and complexity at the topmost IF level determines each individual's Max Capacity. At a sufficiently complex level, there's no time for the brain to find the right set of IFs in which to place new input, or to define new IFs in their proper relationships to others. So brand new IFs are created - short term memory. III. Reorganization => Dreams Note that sleep is often required more when there is more mental activity. In this interpretation, sleep affords the mind time to reassimilate the new IFs into the existing IF structures and to create new IFs (when needed) in proper relation to the totality of existing IFs. Dreams are the "bubbling up" of the various pointer paths (and their associations) which are touched upon during the assimilation process. The more complex the IF structures, the more complex the dreams. Less active minds, for example, often dream in b&w, whereas more active minds might dream in color, and so on. This is why people's dreams have some correlation to their outside stimuli (night- mares, wet-dreams, inspirationals, whatever). The term "bubbling up" is used here to represent whatever other brain functions are involved in actual "conscious" manipulation of sensory data/thoughts; they inherently send "experiences" to short-term memory (create new vectors). As a re- quirement of survival (in evolutionary terms), these "conscious" functions are never fully off-line (unless you're comatose...), so when the memory associations are touched, they "pass through" the conscious functions and NEW short term memories are created in the process: we wake up and remember dreaming, sometimes we remember vividly the dreams themselves, sometimes just some vague associations. Often outside stimuli that occur nearby while we sleep (cat scratching, door creaking, etc.) are reflected in the dream among the memory associations currently being touched; often they dominate. Perhaps psychoses can be interpreted as a short-circuit between the real-time conscious intepretation/manipulation functions and the assi- miliation functions, such that dreams and reality overlap and feed-BACK, like when you are barely awake or barely asleep - when you have some conscious control or awareness in a dream. IV. "The Recall Sensation" => Deja Vu Everything we do that generates some kind of sensation is stored, but in a heirarchical IF structure system, new occurrences of old experiences aren't stored again - when you burn your hand on the stove, you don't re- learn that hot burns, you recall that hot burns because that sensory asso- ciation is already deep down. It isn't anything heavy for your brain to process. If we truly stored everything, the world would probably seem almost as fresh and new as when we were very young - you know that sensation. Perhaps this is one factor in the distinction between a self-aware mind and otherwise. But I digress... Even the process of consciously trying to remember something has a sen- sation. If you do this on a regular basis you'll know what I mean. You concentrate, follow associations backward...until....BANG! You remember! That process has a certain FEELING to it. And that feeling is stored. I submit that deja vu is simply an accidental stumbling upon the memory of that feeling. Some mistake, necessary bypass or whatever in your brain's IF assimilation process has caused a new experience to trigger the feeling of having remembered something - the new experience feels like an old experience. I see no reason to believe this is strange. Perhaps I'm crazy myself, but it seems that occasionally I see something that isn't there, or hear something that didn't happen, or feel something brush my skin when nothing is there. That's the same thing. In a relaxed, stressed or other state my new input occasionally triggers old associations. I would assume that various dietary factors which influence our immediate chemical state have an effect on this cross-over, and this might also help explain why the specific chemical attributes of certain drugs like LSD have the perceptual effects they do. Well, that's it. Feel free to replace my awkward terminology with whatever correct terminology exists and to fill me in on current memory, dream, deja vu and/or drug theory as it applies. Richard Hogen richard@sci.ccny.cuny.edu
jgsmith@watson.bcm.tmc.edu (James G. Smith) (07/02/90)
For another perspective on how the mind and memory may work, you might be interested in reading Marvin Minsky's "Society of Mind." Many of Minsky's ideas seem related to what you mentioned. * (I'm only half way thru the book myself)