The Persistence of Memory and Environment
 By Michael Anthony Ricciardi

    Sometimes a simple truth concerning the nature of reality is so fundamental that we fail to consciously notice it. Only when our attention is called to it, do we say, “Of course, how obvious…” The profound interrelationship, the deep co-dependence, of memory and environment is one such truth. Like a fish swimming obliviously in its invisible, aqueous envelope—only sensing its proper medium in a rare moment or two as it breaches the surface into air—we often fail to see how crucially environment sustains our memory, and without which, we have no identity.
    Since some obscure point in my youth, I have pondered the mystery that is memory. That which we use virtually every moment of our lives—what we all depend upon for even the most mundane or trivial of tasks—was a thing of profound perplexity to me. How did a ‘living’ image return to my awareness after so long an absence? Where did memories ‘go’ when they were being forgotten? How did my brain manifest the words, smells, sounds, and sights that shuffled between waking life and dreaming sleep? If I lost all memory of my past, would I cease to exist? Could memory ‘escape’ the brain and exist independently?
     As I grew older, I learned that scientists too were perplexed by this ‘thing’ called memory. For, as I learned, much study and experimentation was being conducted to elucidate these mnemonic processes. I was truly relieved to learn that our trusty scientists were hard at work, delving into our brainy-matter depths. Still, even knowing that greater (and better funded) minds than I were on the case, my wonderment would return quite often and my personal explorations would recommence in earnest.

Through A Landscape Darkly
    As it often happens, a chance experience would re-connect the two concepts (memory and environment) in my mind, triggering an on-going ‘Chautauqua’ of related thinking. I had always been fascinated by so-called ‘surrealist’ art—from the time of my first art history class in high school. In the first week of class, we were treated to a lengthy slide show of notable works from Western culture. The sanctioned sequence of images was intended to ‘end’ with the modernist era, and so, the reproductions of surrealist art did not appear until the class was nearly over. The teacher, aware of the time constraint, began clicking the ‘forward’ button faster, creating a rather jarring sequence of images accompanied only by the spoken names of the artists. The last image projected was the famous painting by Salvador Dali entitled ‘The Persistence of Memory’. The class bell rang, and the teacher left that last slide showing as we grabbed our books and made to leave for the day. This image would stay with me throughout the day and beyond (though I failed to note the appropriateness of this).
    Most everyone has seen a textbook reprint or poster of this intriguing painting: a starkly vivid, ghostly landscape featuring a stunted, naked tree limb draped over by a ‘melting clock’. The painting shows two additional deformed clocks and a pocket watch, as well as other forms both ‘natural’ and ‘artificial’. The image is quite memorable. A ‘melted clock’ is what most people remember about this painting if asked to recall its content. The scene is at once both alien and familiar (how should this be?). Over the years, I would come to recognize this fusing of impressions as the hallmark of much surrealist (dream like) art. And I would recall this image (though incompletely) numerous times throughout my life—sometimes quite randomly, it seemed—and often with a subliminal sense that there was something more that the painting was ‘trying’ to tell me-- something fundamental to my ruminations. But, like the morphing imagery of a dream it eluded me.
    Dali’s title for this painting declares its subject (‘The Persistence of Memory’) and I note that he had chosen to paint his ‘topic’ in a vividly defined landscape --one that gives the viewer the impression of infinite dimensionality, of endless horizon. Yet, the painting is a mystery. To what does the title refer? Put another way, how does the painting depict its subject? It is not simply an example of a Surrealist ‘game’ technique—of randomly selecting words that force one to find connections—though this is present to some degree in much surrealism. No, a clock however deformed, is an apt enough metaphor or symbol for ‘memory’ in its function of marking the passage of events…but the title is ‘The Persistence of Memory’, not simply ‘Memory’. This persistence implies a continuous activity. How are we to infer this activity from ‘melting’ clocks? At best, they would seem an antithesis of ‘persisting memory’. And what of the other elements in the painting--what were they telling me? I would stare at the painting sometimes, expecting some strange ‘ghost’ to emerge and speak to me the simple key that I was missing.
    Eventually, I would make crucial connections—the linkages between image and idea—that would become the germ of this essay. The heuristic that is Dali’s Persistence would continue to tease me with its clues until one night of occupied insomnia when those clues would coalesce in my dreamless mind…and there it was:  the persistence of memory is made possible only through the persistence of its environment. Environment permits the very possibility of memory—it is not simply a ‘back drop’ against which memories resolve. It is the physical and organizational matrix of all mnemonic ‘bits’—of any mental entity or idea. 
    Now, I realize that to make this assertion, I must endeavor a more precise, working definition of ‘memory’. It seems plain that whatever we come to define memory as being, it is most certainly a process. Through this memory process, some thing—let’s just call it information--is retained, and that ‘same’ something is later retrieved. We know that this information is retained because we can recall it, again and again. As William James famously noted, “the only proof of there being retention is that recall actually takes place.”  However, information, by itself, is not memory. And both processes--retention and retrieval--require some medium of storage, an ‘information sink’, to phrase things in a more technical sense. And this requirement is absolute. Memory necessarily refers to an environment of some kind. 
    Upon considering this fact, I quickly realize that there are different forms of memory, and certainly different types of environment. In the scientific domain, the environment is often reduced to/equated with a system—a pattern of relationships between elements defined as belonging to the system. ‘Environment’ would seem a more inclusive term, but relatively congruent with the notion of a system. And at this point, I recall an observation of R. Buckminster Fuller’s: “all systems have ‘insideness’ and ‘outsideness’”. For, there are systems within systems, and environments within environments. The inside of one environment is the outside of another. We may say that ‘environment’ is a function of our present frame of awareness. And within these systems there arises a phenomenon called memory—which is itself manifested in different forms both genetic and epigenetic (and even extra-genetic)—and which becomes inseparable from the medium that ‘stores’ and (re)produces it.
     So then, in exploring these phenomena, I will necessarily use the term boundary, or other terms that signify a boundary. But in doing so, I recognize that in both the physical and mental domains no boundary is absolute. A cell membrane, for example, is ‘semi-permeable’, as it must be to sustain its being. A boundary may be crossed or re-crossed. To speak of memory, one is naturally compelled to speak of the brain and its structural components. And so, as I enter into the murky realm of brainy matter, I acknowledge that I will re-cross its boundaries often—‘jumping outside the system’ of my present awareness--so that I may explore the ‘outer environment’ of sensory stimuli and physical phenomena…and that collective of systems comprising the ecosystem. And, in so doing, I will also cross the semi-permeable boundaries of ‘self’ and ‘other’.

From Dali to Glia
    When people visualize the structure of brain matter, they typically envision the grayish, sausage-like convolutions of the cerebral cortex. If asked what this cortex is comprised of, most will say “neurons”. Collectively, these cells are commonly referred to as ‘grey matter’. But in brain science, grey matter refers to the ‘cell body’ and its dendrites-- the branched extensions of a nerve cell that receive incoming signals. There is also ‘white matter’, which refers to the neurons’ longer axons that stretch out from the cell body to other cells and transmit these signals. The axon’s myelin sheath (its lipoprotein coating) gives it a whitish appearance. But even if we take into account these two forms of brain matter, we still ignore nearly half the matter that comprises our brains: glial matter. 
    Derived from the Greek word for ‘glue’, the purpose of glia was, for a long time, largely a mystery. It appeared to be simply the ‘scaffolding’ upon which our neural nets wove themselves. Recent experiments attempting to grow neurons in vitro failed to produce functioning synapses (the gaps between neurons that signals must cross) in the absence of glial cells. Subsequent research has revealed that glia provide nourishment for growing neurons, as well as reabsorb neurotransmitter chemicals used in neural communication. Additionally, brain analyses of patients suffering from Alzheimer’s, MS, or stroke were shown to have patches of ‘gliosis’-- a ‘scarring’ that forms around damaged neurons. For a while, scientists believed that this gliosis was causing the damage, and the loss of memory that coincided with it. More recent study has revealed a more protective role for this scarring: special types of glia cells known as microglia—serving as the central nervous system’s endogenous immune cells--form a protective tissue structure around damaged neurons, preventing them from making contact with healthy neurons. As more research has been conducted, scientists have revealed ever more complex roles for glial matter. It has been discovered, for example, that some glia cells exchange information with neurons at synaptic junctions and can alter the informational processing capabilities of neurons.
      Despite this new research, to most brain scientists, glial matter is the brain’s underpinning architecture—its ‘supportive’ environment--with its purpose being to nourish, stabilize, and protect the grey and the white. Memory and ‘information storage’, however, were reserved for neurons alone.
    But as always, science is never settled, never complete. A new and intriguing hypothesis from the frontiers of theoretical biology offers further support for the premise of this essay (in addition to furthering brain science); an interdisciplinary exploration into the behavior of glial cells was conducted by researchers at the Florida College of Dentistry and the McKnight Brain Institute (Robert M. Caudle, et al) using what are known as cellular automata. Cellular automata are computer generated, two-dimensional models of cell behavior and interaction. These automata may be programmed to interact according to a great range of variables. In one most recent experiment, scientists compared certain cellular automata models with the activity of sodium (NA+) ion channels in the membranes of certain types of glia cells known as astrocytes, so named for their star-like structure. When these cell models were pushed towards the ‘boundary of order and chaos’, they behaved similarly to the ion channels in astrocyte membranes. This boundary between ‘order and chaos’ is significant because, in approaching it, the cell achieves a more dynamic state of being, and this allows for the exploration and possibly the evolution of new behaviors. There is also evidence that this transitional state allows for a type of emergent computation, which implies some form of memory.
    It has been speculated for a while that ion channel activity is a cell’s means of storing certain forms of cellular information. Further analysis of these model cells indicated that memory could be stored in glia matter for an entire lifetime, and that this hypothetical memory is both temporal and associative. What is perhaps most curious of all, is that this ‘memory’ was not stored in a particular place on the model cells, but was preserved through the organizational pattern of state changes of the ion channels. Through the coordinated, patterned activity of ion channel changes, the glia, it seemed, were acting as a dynamic ‘information sink’. It seems almost contradictory: memory, though dependent upon a certain ‘architectural’ environment, need not be fixed in place; it reveals itself to be, at times, a far more fluid thing than we once thought. 
    The verification of this mnemonic potential for glia has yet to be wholly confirmed in actual living cells, but such models do indicate, theoretically, a deep interdependence between memory and environment. 

Mo’ Memory…
    Returning to the idea of environment-as-system, there is an important observation to be made here regarding what I shall call the meta-environment, in which, and from which, memories emerge, and have their being. Memories do not simply exist in a physical environment of neurons and glia, but as well within a ‘higher order’, immaterial environment. This ‘meta-level’ environment is the collective of related memories that exists invisibly but concurrently within our brains. These memories, like glia to neurons, serve as the support structure for any newly formed memory. Memories, like people, exist in a societal web of relational being. So then, let us take a closer look at this ‘society of mind’.
    The retrieval of memorized information (remembering) results when ‘incoming’ information is integrated with the ‘memory network’ associated with that type of information. This memory network is the sum total of related, past experiences--the co-existing ‘background’, of our retrieved memory. Necessarily and consequently, this retrieval process fashions new memories. According to noted memory researcher Susan J. Sara, it is “inconceivable that new memory can be acquired independently of retrieval of past experience”. Upon reflection, we can see that memory of the past guides, organizes, and interprets our current perceptual experience. And for this new experience to be usefully (meaningfully) remembered, it must be consolidated within the network of related memories. The new memory must ‘fit’ within the established eco-system of co-existing, long-term memories.
    Related studies on memory and learning emphasize the importance of ‘context’ in what is known as memory reactivation. Everything that we have learned exists as a memory or series of connected memories (such as each step in a complex task). Often, learned behaviors are forgotten due to time lapsing, stress, brain injury, and/or disease. Researchers have discovered that reacquainting the subject with the context of the learning experience promotes the reactivation of that forgotten, learned behavior. This reacquainting process involves a re-staging of the cues--the environmental stimuli—that were present when the original learned behavior was achieved. It is interesting to note here that in order for one memory to be recovered, another type of memory (the past environmental cues) must be presented as ‘triggers’. We can see that the concepts of ‘context’ and ‘memory network’ are congruent, and are analogous ways of saying, or referring to, the ‘environment’ (and all that, by our definition, comprises it). 
     Sometimes, a recalled image or memory is a bit ‘fuzzy’, or fragmented, but generally, we recognize it as the same memory. But this recognition is somewhat self-deceiving; as time passes, specific memories do change. In fact, they do so slightly each time that we recall them. Each time that a memory is retrieved—even a fuzzy, unclear one—the brain ‘fills in the blanks’ a bit more, until what is last produced is now a clearer, more complete memory. 
    The foregoing having been said, exactly how a mental memory is encoded, stored, retrieved, and decoded in the brain remains largely a mystery. Over the years, many theories have been put forth: myelin protein folding patterns, holographic wave (interference) patterns, ion-channel ‘gates’, and ‘maps’ (microtubule associated proteins), to name a few.  
     Even still, many scientists look beyond these micro-level details and view the production of a memory as a type of emergent phenomenon; under the right mental and/or environmental conditions, a memory ‘emerges’ from the cerebral matrix like the proverbial ‘ghost from the machine’. Emergent Evolution is a modern notion that seeks to describe new phenomena as being the result of the ‘rearrangement of pre-existing elements’. 
    
From Inner to Outer: Crossing the Boundary
    Let us for now traverse the boundary of brain and membrane, and focus our awareness onto the ‘outer’ environment. Could memory, I wondered, somehow be preserved in the outer environment of sensory stimuli—the external world of ‘concrete’ matter? At first, this question seemed reasonable enough. But upon considering that the ‘external world’ is comprised, in part, of countless life-forms, each containing a genetic memory, I realized that my question was inexact. And I did not wish to discount this form of memory, for, it is indeed a molecular ‘memory code’—and one completely dependent upon its immediate, local environment (the cell) to replicate (hence preserve) itself. Further, many cells are part of a larger, meta-cellular organism (like a person), which is also its extended environment. And this meta-cellular creature too exists within a larger environment, etc. Again, “All systems have ‘insideness’ and ‘outsideness’.”  
    There are also entities which are called ‘memes’ [see Richard Dawkins et al] which are immaterial, cultural replicators – such as a jingle from a tv commercial, a funny one-liner, or an unfortunate quote from a political candidate. Due to some inherent meaningfulness or utility (or ease of saying), these self-perpetuating memes act as a non-genetic/biological form of memory that operates according to its own rules of reproduction, and even ‘inheritance’; we inherit, or acquire, these replicators directly from others—from our social environment--and from the larger cultural environment in which we are constantly participating. Memetic memory illustrates the complete dependence of such memory upon its environment. In this case, there are (at least) two environments which simultaneously contribute to and support the memetic ‘unit’: the inner environment of brain/mind (the structures that produce and preserve thoughts, poems, songs, verbal memories) and the outer environment of cultural media and artifacts (which transforms the former, and offers potential memes as content). Memes, given the right supportive environment, are autonomous and, in competing with others, are subject to their own form of natural selection, and follow their own ‘survival of the fittest’ ecology.
    These forms of memory, like the brain’s memory, can be considered, in a literal and expansive sense, as ‘extra-genetic’, or perhaps even metagenetic. I will return to a discussion of those genetic forms of memory later in this essay.
    What I meant to question earlier was the possibility of a more basic, ‘primitive’ form of memory—one that can exist, in some form, wholly separate from living matter? Did the extra-cerebral, physical environment have the potential to preserve memory, to act as an ‘information sink’? Was there any evidence from the sciences of natural (inanimate) structures having this potential?
    As a kid, I was quite the ‘rock hound’, and, like most youngsters, totally fascinated with dinosaurs and fossils. My first fossil was of a tiny sea-dwelling creature named a trilobite which was dated at 400 million years old. Although my scientific interests would blossom in many other fields, I considered these two fields—geology and paleontology—to be my firsts, and I have always retained my early interest and appreciation for all things stony and old.
    Looking at my tiny, pebble-like trilobite, I could easily make out the creature’s detailed features—the two rows of legs, the head and body architecture—and I could see that it was clearly no ordinary rock. Of course, a fossil is mostly rock; most commonly, a dead creature’s bone tissue or teeth having been replaced by a process termed permineralization, and far more durable in this form than in its original (it did last 400 million years!). Not all ancient dead creatures were preserved as fossils. The successful preservation of a life-form as a fossil depends upon the medium of preservation; the soil/sediment must be fairly uniform, or homogeneous. Limestone, clay, and/or smooth sedimentation are the ideal environments for a well-preserved fossil; too heterogeneous a mixture of ‘ingredients’, and the likelihood of whole or even partial preservation is diminished greatly. Also important: the climatological environment; sudden changes in heat, moisture, acidity, or pressure can destroy any chances for fossilization. There is perhaps no greater example of the inseparable nature of memory and environment than a simple fossil. But perhaps you feel that this example is only somewhat removed from the example of ‘life-form-as-memory’ given earlier. For, the fossil was once a living thing. So then, is there any ‘harder’ evidence for memory existing apart from living matter?
    Fortunately, I have my geological knowledge to fall back on. Far more than the mere study of rocks, geology seeks to uncover the geologic past, the history of the earth’s formation and activity. In geology, there is a phenomenon known as paleomagnetism, which involves an ‘ancient’ magnetic feature of the earth. There are a great many layers, or strata, of hardened volcanic rock comprising the earth’s crust, with each deeper layer usually being older than the upper-most one. Many of these strata contain quantities of a crystallized mineral called magnetite, which is a magnetic ore of iron. As molten lava is extruded onto the surface, these magnetite crystals, being magnetic, become polarized according to the polarity (the direction or flow of electrons) of the strongest magnetic field in the vicinity. When the molten rock cools, the magnetite crystals are ‘frozen’ in place. These younger strata which are closest to the earth’s surface, being also closer to the earth’s magnetic field, possess crystals whose polarity matches that of our planet’s protective field. In deeper layers, however, this is not always the case. As it turns out, geo-scientists have discovered that some of these deeper layers revealed magnetite crystals whose polarity was opposite that of the current geo-magnetic field. In short, their poles were reversed (and sometimes in transitional stages of reversal)—their ‘north’ pointed south, etc. These results have been confirmed many times over. In identical strata separated by great distances, the crystal polarity was the same. How could this be? It was as if the ‘magnetite memory’ was telling us that the earth’s magnetic field had changed—many times—quite radically.
    In fact, most scientists now agree that this is exactly what has happened. What’s more, current measurements of the upper-most, magnetite-bearing strata indicate that the earth’s magnetic field is currently undergoing a major polarity shift. One day in the distant future our compass needles (in the northern hemisphere) will point south! What this means for the earth—and how long such a reversal will take--is a matter of on-going study. Not to sweep aside the potentially significant impact of this reversal, the point of all this is to illustrate the existence of a type of memory preserved in the non-living, external environment. It is as if the earth were a gigantic recording device, with the magnetite crystals’ polarity acting as the ‘memory code’, and the general rock strata serving as the environmental information sink.
    Of course, you may note that the recovery and analysis of both fossil and paleomagnetic evidence is being facilitated by the human brain. Essentially, the brains of scientists (aided by computers) are acting as ‘retrieval devices’ complete with their own internal memory environments. So then, these examples seem to support my idea, but at the same time, they reveal the obvious and vital link between memory and environment: consciousness. Evidence of memory that is external to the brain and living matter can not be observed, collected, or analyzed without using the brain—complete with its inner ‘memory network’ of associated memories, its memory aids (storage/retrieval devices), and its own neuro-biological environment of white, grey, and glial matter. 
                                               
                                                  From Glia to Ghosts
    Lest the reader feel that all worthy investigations of this topic involve physical (‘scientific’) phenomenon, I should like to diverge a bit into a consideration of the meta-physical, the occult realm of ‘ghosts’ and ‘hauntings’. For, although as a youth I was deeply absorbed by the ‘natural’ and ‘scientific’, my intellectual interest was almost equally taken with matters decidedly ‘supernatural’ and ‘mystic’. To be honest, I would eventually have trouble accepting the objective reality of ghosts and other ‘paranormal’ phenomena. Though still willing to entertain such notions, I began to doubt seriously the paranormal claims and ‘visions’ that I read about and occasionally heard others speak of. I had read so many strange-but-true tales that later turned out to be largely fabricated (or poorly reported)…had had my beliefs in ghosts and spirits (and those darned “ancient astronauts”) dashed to pieces so many times that, as I grew older, I could only entertain such notions through the unblinking eyes of a natural scientist. Refusing to accept any ‘supernatural’ theory, I dedicated myself to finding a likely, natural cause.
     And so, I began to apply a good measure of skepticism whenever I was confronted with the possibility of ‘discarnate’ entities roaming through old mansions or boneyards. This would lead me to re-define what is meant by the word ‘ghost’.
    I’m not sure how old I was when the thought occurred to me that perhaps a ‘ghost’ was simply a form of memory that had somehow ‘escaped’ the brain/body that had produced it. This thought was followed very quickly with the realization that-- if such a thing were possible —the physical environment had to play a crucial role in its preservation. Somehow, intuitively, I recognized that an ‘immaterial’ entity, that chose to manifest itself nevertheless in this material domain, could only do so given the right physical conditions—and the ‘right’ consciousness to perceive it. I tended to reject the ‘trans-dimensional traveler’ theory of ghosts as this was an unending, metaphysical postulate, and ultimately, unsatisfactory to my quest for understanding.
    Consider two types of environments that are most often cited as being ‘haunted’: houses and graveyards; the first being a structure for living humans (and sometimes their pets), and the second being a location for deceased humans (and sometimes their pets). 
    I can recall, vaguely, having had many dreams in which I was roaming through some old, multi-storied house…sometimes ending up in the basement, other times in the attic. And I recall reading some book on psychoanalysis and dream interpretation in which it was asserted that a house, in a dream state, signified or symbolized the mind itself. The rooms through which I wandered were, accordingly, differing ‘areas’ of my mind (or unconscious), each being the residence of specific types of memories, both recent and ancient. How valid this assertion is, or was, seemed less important than the idea that a house—with its many floors and rooms—was somehow deeply related to my inner-most memories. And truly, as I entered each new room, or area of the house, my dream state would conjure up its soup of strange and familiar events, people, fears…and, of course, how common were the ghosts that wandered there with me (my deceased father, that strange kid from 5th grade) …
    Once, when I was a daring (i.e., bored) teen-ager, I dared myself to sleep in a cemetery. It was only a stone’s throw from my house, for I was not yet so daring as to do this without the possibility of escape to my warm, secure bed. This particular cemetery was fairly large and quite wonderfully landscaped with numerous mounds and reflecting ponds. It was, to my teen-aged mind, unexpectedly beautiful. Before sundown, I decided to explore a bit. There were gravestones dating back to the early seventeen hundreds (this was Massachusetts) with engravings so weathered that identifying the names and dates was almost impossible. Some were actually smashed—the work of thoughtless youths, no doubt. I wondered if the groundskeeper still had the records of these older stones, and whether if he had, if he could repair or restore them. If these markers were left in such a damaged state, I wondered, how would anyone know who was buried there? The thought troubled me, although in an inchoate sense, and I had not yet begun my internal discourse on memory and environment.
    Now, a cemetery or graveyard is entirely and intentionally a place of remembrance. The bodies once buried beneath were now only bone. We know that there are/were corpses in the ground solely because of the markers we leave—bearing the names, the life-spans, and sometimes the hopes of those who have ‘gone before us’. Some headstones bore short quotations of poetry, usually of a mystical bent; seldom humorous. Cemeteries are also normally quiet and peaceful and possessing well-manicured topologies with trees, shrubs, glades, reflecting pools, stone paths, and monuments to the war-fallen. Is there any more ideal environment to encounter a ‘ghost’? But of course, very seldom do we see ‘real’ ghosts—the ghosts like the ones in the movies or on television. 
    To restate my viewpoint: a ghost is a form of memory. And just as there are different forms of memory, so too there are different forms of ‘ghosts’. On a basic level of awareness, these different forms may correspond to the ‘memory domains’ that are being occupied—whether it is the ‘inner’ environment of mind or the ‘outer’ environment of the local cemetery. Regarding such ‘inner’ ghosts, even a skeptical scientist type (like me) would not have too much resistance to the idea that the mind (or brain) is occupied by ‘ghosts’ of a sort, especially given my definition. Carl Jung wrote: “There are things in the unconscious which I do not produce but which produce themselves and have their own life.” Some of the content of mind is autopoietic, i.e., self-creating. Perhaps also, these inner, mental ghosts are ‘rogue memories’—unable or unwilling to fit in with their proper ‘memory network’, and forever cursed to roam the corridors of my dreams. Very well then, it’s a bit colorful and poetic, but certainly not a hypothesis beyond plausibility.
    It’s the ‘outer’ ghosts that cause concern from the scientific viewpoint. People who claim to see such ghosts describe them alternately as somewhat “fuzzy” (semi-transparent) or “solid as you and me”. Perhaps the degree of solidity verses transparency is the result of the ancientness of the putative ghost. Or, perhaps the memory associated with it is deteriorating. Whichever, whether solid or only semi so, such ghosts can vanish in an instant, then reappear again without warning…no room or wall or boundary can contain them, or keep them out, and they are often in the company of other ghosts…In short, ghosts behave very much like memories do. But these ghosts have somehow been decoupled from the brains/bodies that once produced and possessed them.
    There is a fairly rare phenomenon experienced by some individuals known as an eidetic phenomenon. The eidetic vision is half dream, half hallucination, but technically neither. Such eidetikers can project their mental imagery onto the external physical environment through a process not fully understood, nor fully accepted as real. The nature of the physical environment (light/dark, the architecture, etc) seems to be as crucial to the generation of an eidetic phenomenon as the person ‘causing’ it. I suspect that those with this ‘external projective’ ability are mentally predisposed to seeing visions, and also, on some level, absorbed with the history, the received lore, of the house or haunting in question. A combination of these factors is a fair recipe for a ‘ghost.’ It is significant to note that two or more people rarely report seeing the same ghost at the same time, although it is still possible. 
        Now, an old house or graveyard is each an ideal locale for such ‘ghosts’ to inhabit or haunt. These environments are, on many levels, ‘information sinks’ of a special class. Each possesses unique markers for the memories stored or hidden therein. Each is imprinted with signs of former human occupancy and activity. And of course, like the tree that falls in the forest that cannot make a sound without a perceiving consciousness present, a ghost-memory cannot appear without a consciousness to ‘call it forth’—to serve as the information retrieval device that all embedded or forgotten memories require to become ‘reactivated’.  
    Also, recall my earlier mention of ‘non-locational’, information storage (via glia cell automata) and that such information, and hence memory, need not be ‘fixed in place’, etc. Rather, it is possible to preserve such memory through an organizational pattern of state changes. Such patterns would be quite dependent upon the under-lying nature of the ‘supporting’ matter (wood, metal, mineral, etc.). Perhaps, there is some analogous organizational pattern in the fluctuating ‘ionic fields’ present in these locales, and this pattern preserves a memory of some kind—allowing for an ‘emergent’ phenomenon (the ghost-memory).
    I could be wrong about some, or all, of that. But it makes a more natural sense to me, and it enables me to embrace the notion of a ‘ghost’, instead of rejecting them as the earnest imaginings of a suggestible mind. There is something truthful there…

Back to the Physical
    At an earlier point I spoke briefly of the myriad life-forms that are manifest from genetic memory. I should like to pick up this topic again, and so I cross back into the bio-physical domain, and from there, back and forth betwixt genomes and their habitats.
    All life forms possess a genetic code in some form, be it DNA (in plants and animals) or simply RNA (in the case of viruses). These highly complex molecules, most with their own localized environments (the cell) and ‘sub-environments’ (the nucleus/nucleolus of the cell), provide the memory ‘recipe’ for making and re-making a living thing. While viral life-forms provide an exception (although even viruses possess protein shells or lipid bi-layers), most life-forms require a cellular membrane—an environment within the environment—in order to shield themselves from all the ‘hefts of the moving world’(Whitman). These membranes, individually and collectively (in the case of a multi-cellular life-form), define the relationship of the living thing to its environment; they are the boundaries that Life puts in place to preserve itself—and in so doing, and so being, to distinguish ‘itself’ from what is ‘other’. Perhaps due to this simple structural reality, the impression that memory is separate or distinct from its environment persists.
    To focus a bit more precisely on this inter-relationship, let us consider the thing called a habitat. A habitat is an external ‘sub-environment’, if you will, that has unique features (such as climate, vegetation, water) that the life-forms inhabiting it must adapt to. An adaptation may be viewed as the manifestation of the life-form’s ‘geno-environmental-interactive history’. Slightly differing traits among related species can tell us about their genetic and even geographic history. Sometimes two populations of the same species—such as birds—become separated by geological barriers. Over time and generations of restricted breeding, this separation enables a ‘bifurcation’--a splitting into two distinct species or ‘sub-species’. This is known as geographic speciation and, along with favorable mutation and natural selection, essentially alters specie/genetic memory—even as it preserves it. 
    Reciprocally, some life-forms can alter (even destroy) their habitats, and indirectly change the collective genetic memory of its habitat. Algal lifeforms growing on the surface of a pond can grow to such size that they mat over most of the pond’s surface, blocking out light and chemical nutrients for other plants that live below the surface. As the algae dies, aerobic bacteria feed on it, consuming most of the ponds dissolved oxygen content. Such unchecked growth “chokes” the littoral habitat by starving both the fish and invertebrates (of oxygen), as well as the sub-surface plants (of sunlight and CO2) that provide protection and a food source for microbes and myriad invertebrates--creatures that fish, frogs, and other critters depend on for their food. This lethal ‘domino effect’ can occur under natural and artificial conditions (such as a build-up of detergent derived phosphates).
     Of course, the one life form that alters its environment the most is homo sapiens (sapiens). Humans can and do actively interfere in the functioning of various habitats and ecosystems, with innumerable bad outcomes, and few positive ones (save for short-term benefit to humans). We have been doing this since the start of human civilization. The difference in this modern era is that both the means to destroy habitat and the pace of destruction are proportionately increasing. A May, 2006 study by the Swiss-based IUCN (World Conservation Union) has determined that some 16,000 species of animal and plant life are critically endangered and face possible imminent extinction. It is still shocking to learn that hundreds of species become extinct every year. Of these, maybe ten percent survive in captivity—in various kinds of zoos which are attempts to reconstruct an environment (habitat) to preserve (genetic) memory. Most of this extinction of life is due to the loss of habitat and ecosystems resulting from reckless human development, over-use, and pollution. Humans, of course, also eliminate human genetic and cultural memory—through wars, displacement (such as Amazonian rain forest tribes), and disease contagion. Sadly, no matter where we are, we need not look too long to find examples of this destruction. But to distill this information within the context of my main thesis: when we destroy environment, we destroy memory.

Re-Crossing the Boundary of Self and Other
    Let us return now to the brain and my earlier mention of diseases that result in memory loss. Of these diseases, Alzheimer’s seems to provoke the most dread. In typical, early stage Alzheimer’s disease, old memories are retained, but recent memories grow fuzzy and even ‘vanish’. Eventually, in the worst case scenario, the disease will ‘wipe out’ even the sufferer’s oldest, most deeply ingrained memories, until the victim is reduced to a cerebral ‘shell’ of who they used to be. Unable to recognize spouses and children, or to recall significant life events, the Alzheimer’s patient is left in a terminal void of lost identity—so much is who we are the result of memory of the self’s past. 
    But quite recent research into this disease has revealed a ‘contingency factor’ in Alzheimer’s ability to rob its victims of memory and identity. Doctor’s uniformly associate this disease with the proteinaceous plaques and tangles that spread throughout the brain (it is these plaques and tangles that microglia seek to isolate). This activity, it is believed, is what destroys the cognitive and memory functions of the sufferer’s brain. And yet, investigations of people with such symptoms show that many do not experience the cognitive and mnemonic decline associated with the disease. How should this be? What was causing the differences observed in those diagnosed with Alzheimer’s?
    After assessments of patients’ social lives—their contacts with family and friends—researchers at the Rush University Medical Center’s Alzheimer’s Disease Center (Dr. David A. Bennet, et al) discovered that maintaining an active social network seemed to be the primary source of the difference in Alzheimer’s patients. According to the researchers, having many friends and preserving contact with family acted as a “protective reserve” against the damaging effects of the disease. After analyzing numerous cognitive test results, the researchers discovered that those Alzheimer’s patients with the most extensive (largest) social networks had the highest test scores, that is, their cognitive abilities were least impacted by the disease. I also note here that these patients scored highest on a cognitive task involving semantic memory. Our semantic memories enable us to derive meaning from language—and thus participate fully in the linguistic environment that sustains much of our culture. This research indicates that an expansive, active social environment is crucial to the apprehension of ‘meaningfulness’ as conveyed though words both spoken and written.
    When considering one’s ‘environment’, we often forget to mention the people—the relationships--that come and go within it.  We often view our environment solely as the collective of things or conditions that constitutes it. Clinical terms like “social network”, while technically descriptive, only hint at this omission. Nearly three generations ago, in his ground-breaking book The Sane Society, socio-philosopher Eric Fromm repeatedly emphasizes the “human need for relatedness”, that is, that the forming of emotional bonds with family, friends, colleagues, and others is a fundamental requirement for proper emotional/psychological growth. When this need is stymied in some way, we risk our mental health, our sanity. So, given this need, the previously noted clinical findings should not come as that great a surprise. 
      Having a disease such as Alzheimer’s does not mean that we are fated to the pathology of that disease. We are not simply ourselves, we are others as well. That is, who ‘I am’ is related to who ‘I know’, in the sense of emotional knowing. Like a new memory that must be fit into its associated ‘memory network’ prior to its consolidation, our cognitive life—our inner environment of thought and memory--must fit into a social network of related minds in order to become ‘solid’, that is, resistant to impairment and pathology. In a disease such as Alzheimer’s, where we see so vividly the inter-relationship between memory and identity, we also now see their dependence upon the (social) environment, which is to say: when we preserve environment, we preserve memory.

Back to Dali: Ghost from the Dreamscape
    As I near the end of this thought piece, I should like to return to that “night of occupied insomnia” and the realization that came to me then:  the persistence of memory is made possible only through the persistence of its environment. This realization came to me as the image of Dali’s painting appeared in my thoughts, spontaneously. Almost immediately after this strange epiphany, I began to compose the principle theme of this essay. Eventually, I was compelled to get up and draw the ‘concept map’ that traced the connections between the various ideas then running amok in my mind. Only then was I capable of returning to bed, and eventually, falling asleep.
    Upon waking the next morning, I grabbed a book on Surrealist Art from my bookshelf and hurriedly flipped through the pages in search of The Persistence of Memory by Salvador Dali. There it was, though somewhat different than in my recollection—I had forgotten some details, and had added others that were not there. What I noticed most of all was how different the landscape depicted in the painting was from my earlier memory of it. The mountainous cliffs in the distance were, in my original memory, much closer, and comprising much more of the painting. Forgotten also was the distant sea, the total number of ‘melting’ clocks, and the two, curiously dull slabs of material occupying the left side of the painting. How innocuous, even clumsy, to include such forms, I thought. But, gradually, what became clear to me was that these forms are decidedly ‘artificial’ in construction--too geometrically perfect in contrast to the ‘natural’ structures. And I notice now that the deformed time pieces (and the one, bug-covered pocket watch) are draped/placed either on this (foreground) artificial block or in close proximity to it. This arrangement connects to an earlier notion: we construct our memories even as we remember them. 
    And the ‘stunted tree’ (holding one of the clocks) that grows from the foreground block, appears, upon renewed investigation, to be clearly human-like in its grey morphology and gesturing branch. It is as if the tree is offering its clock to the landscape—or perhaps to the strange form that lies on the ground. This strange, fleshy form lying just beneath the branch, drapes over some (mostly) obscured, zoological form—one that immediately recalls a fossilized creature, poking through the barren earth. The flimsy, purplish ‘skin’ that covers it (itself draped by a molten clock), fades off into the distance, vanishing down (what appears to be) a hole. It is, I now convince myself, a chthonic ghost-image: at once both familiar and alien, solid and ephemeral. It is a literal, if oblique, reminder that ‘figure’ and ‘ground’, like memory and environment, are inseparable.
    And now a second realization hits me: the deformed clocks, like my mal-formed memory of the painting itself, are unavoidable consequences of the confluence of time, consciousness, and environmental flux. Some features of the world seem to remain solid and stable, while others seem more obviously alterable. In truth, everything is changing, transforming. The spatial-temporal environment—and its dependent memory--is no different. Just as environments change, so do memories. The price we pay for the persistence of memory is the distortion of memory. But this is better than the utter loss, the perishing, of memory, by far.
    All worlds, all environments, embody instability. It is what makes all life, all being, ultimately possible. We can no more remove this instability from the environment than we can separate who we are from what we remember. The trick is not to alter the environment such that we counter the drive of memory to persist in it. It is, after all, who we are that we seek to preserve.  Our memory is our environment, the environment, our memory.
    As I reflect on the foregoing, I begin to think: “Of course...how obvious.”  I am like a fish breaching the surface into air.
Michael Anthony Ricciardi

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Reference Bibliography for ‘The Persistence of Memory and Environment’
By Michael Anthony Ricciardi

Memory in astrocytes: a hypothesis
Robert M. Caudle
(published in) Theoretical Biology and Medical Modeling, January 18, 2006

Retrieval and Reconsolidation: Towards a Neurobiology of Remembering
Susan J. Sara
Neuromodulation and Cognitive Processes, Insitut des Neurosciences, CNRS, Paris, France, Learning & Memory, March/April, 2000

Mechanisms of endogenous neuroprotection
Richard Kraig, M.D., Ph.D.
(course description) Dept. of neurobiology, Pharmacology, and Physiology, University of Chicago, Committee on Neurobiology, October, 2004.

Control of Synapse Number by Glia
Erik M. Ullian, Stephanie Sapperstein, et al
(published in) Science, January 26, 2001

Glial Lipoproteins Stimulate Axon Growth of CNS Neurons in Compartmented Cultures
Hideki Hayashi, Robert B. Campenot, et al
Journal of Biological Chemistry, vol. 279, issue 14, April, 2004

Reactive Astrocytes in Neural Repair and Protection
Michael V. Sofroniew
The Neuroscientist, vol. 11, no. 5, 2005

Full Social Lives May Protect Against Alzheimer’s
David A. Bennett, M.D., Rush University Medical Center’s Alzheimer’s Disease Center (Chicago), (article published in) HealthDay, April 28, 2006 

ADDITIONAL:

Author’s notes (paleomagnetism, emergent evolution, statistically emergent mentality, and non-cited quotes [Jung, Fuller, James]), M. Ricciardi

Other sources - cited within text.

[New reference for glial cells:]

Cellular Conductors: Glial Cells as Guideposts during Neural Circuit Development
Daniel A. Colón-Ramos, Kang Shen*, PLoS Biology, April 29, 2008