The Slow Death of the Self that is Produced by the Normal Operation of Human Memory

People are terrified of dementia, by the loss of the self that results from the final stages of the accumulation of age-related damage in the brain. Whether this is loss of data or merely loss of access to data, that data being encoded in the structures of neurons and their connecting synapses, depends upon the details along the way. Either option amounts to the same thing for someone in the midst of the condition when there is only faint prospect of therapies arriving soon enough to matter. But if dementia is an asymptotic approach to 100% loss of data, what to make of the fact that we are, on a day to day basis, largely accepting of our normal relationship with the data of the mind, in which we lose 98% of everything that we experience within a few weeks of the event? A week from now you will not remember reading this, nor will there be any trace of what took place in the surrounding minutes before and after. You will have to guess at how you spent your time, what you were thinking, who you were at that moment. We are, every one of us, thin and translucent ghosts of our own history, mere summaries of a rich set of data that is now gone.

Yet we get by. Normal is normal, but that doesn't mean it is good, or that it should go unexamined. To put this another way, there was a person who lived a few decades ago in the UK, and got by. Later, there was another person who came to the US and spent time here, as people do. I know about as much about those individuals as I do about friends of long standing, perhaps just a little more. Yet both of them were me. All of that remains of them, of their richness of data, are the echoes I carry with me now. I have the memories burned in by adrenaline or, to a lesser extent, by sheer boring repetition, but those are just signposts in the mist by this point. Ask me who I was back then, and the answer will be largely extrapolation. Are those individuals dead? Am I so different that such a question makes sense to ask? To what extent is the self burning away and vanishing because we have a poor capacity for remembrance? To what extent is change death, in other words? Here of course I do little more than wave my hands at questions that have been debated at great length in the philosophy community.

Those of us who are generally opposed to the idea of being scanned, uploaded, and copied have the view that a copy of the self is not the self. It is its own separate individual. Individuality stems from the combination of pattern of information and the matter that the pattern is bound to. It isn't clear that, for example, an emulation running in an abstraction layer over computing hardware can be considered a continuous entity, rather than a unending series of nanosecond individuals assembled and then destroyed. In the continuity view of identity, a Ship of Theseus sort of a viewpoint, you are still you even if all your component parts are slowly replaced over time. There is a sizable grey area at the border between small parts and slow replacement, which is fine, and large parts and rapid replacement, which is the same as death. If someone removes half of your brain in one go and replaces it with a hypothetical machine that accepts exactly the same inputs and produces exactly the same outputs where it connects to the remaining brain tissue, I would say that this means that you just died, even though an entity that thinks in the same way as you did continues onward. Conversely, replacing neurons one by one with machines that perform the same functions, and allowing time for each neuron to reach equilibrium with its neighbors, seems acceptable.

Continuity comes attached at the hip to change of the self over time. Life is change, and we celebrate it. But we lose so very much in the course of that change that it seems matters really could be better managed. The figure for 98% loss of memory over weeks arises from self-experiments carried out by a determined fellow in the late 1800s, and which have been repeated every so often by the research community ever since. A replication paper was published just last year, for example. This enormous loss is the way things work for normal humans, and coupled with the adrenaline mechanism for selective additional memory of events that matter, one can see how this sort of a system might have evolved. A prehistoric lifespan is the same few tasks with very minor variations repeated over and again until death or disability, interspersed with a much smaller number of painful and terrifying learning experiences, with each new generation running the same rat wheel as the previous.

There are claims of people with extraordinary memory, or even eidetic or photographic memory, but the scientific community is far from settled on the question of the degree to which these claims result from (a) misinterpreting the top end of the curve for normal variation in memory capacity, versus (b) narrowly specialized memory training, versus (c) some form of genuinely unusual and exceptional ability based on neurobiological differences yet to be described. The mechanisms of memory are being deciphered in the laboratory, however, and there are various demonstrations of a modest degree of enhanced memory in animal studies. The question of whether greatly enhanced memory can be induced through near future medicine remains open: it will certainly happen eventually, but when will it start in earnest, and when will it go beyond adding only few more percentage points to the fraction of events we recall from our lives? It seems to me that this is a goal that should be given a far greater priority than is the case today. Consider that if we had perfect memory, what would we think of someone who forget near everything he or she did? We would call it a medical condition and offer support, in the same way that the medical community seeks to treat and aid people suffering age-related cognitive decline or amnesia today. If there were a great many of those people, there would be an enormous investment in the search for a cure, just as we do today for Alzheimer's disease. But because our disability is normal and shared, there is no such effort.

Comments

We are concerned with continuity, but continuity of what? As you point out, there's no such thing as continuity of memories because, if we accept memories are the building blocks of self, then we'd have to accept we keep dying all the time. Continuity of awareness seems closer to the right answer, which means continuing the brain process that gives rise to awareness. So gradual replacement of neurons would preserve that process and that awareness.

Posted by: Heartland at December 2nd, 2016 9:42 PM

@Heartland I share your view. But it has a slight problem to it.
Our awareness isn't absolutely continuous by nature - we sleep.
Of course, there is some level of awareness active even while we sleep - we dream, we can be woken up, etc. - but it is an argument I've seen upload cultists perpetuate so it is something we should think about.

Posted by: Anonymoose at December 2nd, 2016 10:35 PM

"Gradual" is a very relative scale, whether for neuron replacement. climate change or the chronology of the universe. I think we can all agree the life is always too short, except when it is interminable. Though I visit this blog for the empirical, I deeply appreciate the occasionally poetic. Thank you!

Posted by: KayAych at December 2nd, 2016 11:30 PM

@Anonymoose, yes, there appears to be continuity problem with the sleep or general anesthesia. However there are enlightened teachers who claim continuity of awareness despite sleep and anesthesia by claiming that awareness is always present and that it is sensory input that is either diminished or cut off completely, which would explain the seeming awareness discontinuity in those cases. I think that's an interesting theory.

Posted by: Heartland at December 3rd, 2016 5:14 AM

Very thoughtful post indeed. One year ago I started a diary and continue to backfill it for this precise reason, to preserve as much as possible of my experiences. This is incredibly sad how much one loses as time passes by.

Posted by: Naufrage at December 3rd, 2016 5:25 AM

A more interesting experiment, than having a person remembering lists and then being queried about them, would be to records everything a person sees during a month using glasses with a builtin camera. Then ask that person about details, for instance, what they ate for lunch? What was on TV? Who sat next to them on the train?

Posted by: Erik at December 3rd, 2016 7:32 AM

The interesting question for me is: If we live longer and longer, do we want to remember everything that we did 100 or 200 years ago? When will it become a burden rather than desirable? And how does a longer lifespan affect memory? Will the brain just remember the last 100 years and wipe out everything before? Granted, I'm probably thinking far ahead here with already greatly extended lives, but that's a question I'm thinking about when extending lifespan: the burden of memory.

Posted by: K. at December 4th, 2016 2:09 AM

@K: Well, we currently live around three times longer than people two centuries ago, so we are already in that situation.

Posted by: Antonio at December 4th, 2016 8:40 AM

Just because we don't save everything we don't need to disk doesn't mean that there's anything wrong with us.

Posted by: Slicer at December 4th, 2016 4:34 PM

As someone who remembers nearly every dream he has and has in the past been able to drop directly into a dreamstate from waking, I seriously doubt there is any true break in consciousness when we sleep. How much you can recall is not, I would say, any equivalence to how much you're actually experiencing. To refer to this very article, if we forget so much of what we know, would it really be any different when we sleep - except in that for most people they forget that much sooner? I don't think that I, as someone who remembers so much, is physiologically divergent in any meaningful way from someone who isn't, so if I can remember that much, I believe everyone else must have the same awareness going on overall.

Posted by: Sadi Khan at December 5th, 2016 2:24 AM

Thanks for once again addressing the issue of "Is an exact copy of you actually you?" Or, "Did Kirk die every time he beamed up?"

Posted by: Art at December 5th, 2016 3:11 PM

@Art,

Agreed. I am totally for SLOWLY replacing component parts, but not the alternatively. Honestly, I can't believe we have to even argue this point. To me, it seems like a no brainer (pun not intended).

Posted by: Robert at December 5th, 2016 6:52 PM

@K.

Hi K., Just a 2 cent.

''When will it become a burden rather than desirable? And how does a longer lifespan affect memory? Will the brain just remember the last 100 years and wipe out everything before? Granted, I'm probably thinking far ahead here with already greatly extended lives, but that's a question I'm thinking about when extending lifespan: the burden of memory.''

I believe it will be 'just more' of it. The brain has the capacity for immense memorization over decades - and more than a single century. With age we have difficulty remembering some of our long-ago very earliest chilhood memories (you know like when sometimes your parents would recall a fact about you when you were a toddler - but, you can't remember it - they can because they brought you up, were there and remember you as a baby), it's with deep concentration that we can 'resummon' these dusty neurons holding our ancient memories - which are mostly 'off' for the remainder of our life - unless they were Ultra-Traumatic events that we remember everytime we think about our 'childhood'; these 'sleeping neurons' are not unexistant, they are there with the memory attached to them, since near birth, but they are dormant and rarely summoned (in fact they are totally forgotten almost like a censoring mechanism, but rather a left-to-sleep mechanism but still there as 'stored data'').
This can be seen in centenarians who remember and can recall extremely long ago memories from their near-birth...imagine a 120 year old centenarian recalling something in their childhood. It demonstrates that we do not 'lose' that precious information (if not succombing to alzheimer's, senility, debility, dementia, mental degenerescence because all centenarians show brain pruning which brain white/gray matter loss; as such at a certain they - do - lose 'data'; and it's also sad and scary to see them 'forget' the name of their spouse (died long ago) or the name of their child...or just forget where they put their keys (this is a start of pre-dementia and Alzheimer's visible in centenarians who don't evade either becaue their brain is become small and it begins to accumulate amyloids too (on top of their life-ending systemic transthyretin accumulation (another amyloid-like plaque accumulating, especially, in their heart). Animals who live above 200 years old have intact memories and can recall areas of exploration and come back to them (such bowhead whales who live 211 years old MLSP or Aldabra/Galápagos Seychelles Giant Sea Tortoises who live 150 to up 255 years old; these huge animals still have some memory - it may not be sharp as that of a 20 year old; granted. But, there brain is very much functionning and its memories recollection too). Plus, bowhead whales are mammals, like us - that tells you it's very possible to translate this memory recollection over 200 years in humans too. The only true way it's going to happen is if we keep our biology to that of 20 year old; simply put. Otherwise, it's not going to happen - to live 200 and maintain memory. At around 120s we reach quite the maximum and the reason for that is because we proceeded to 'age' during the last 70 years (at about 40 everything drops and its downhill slope interms of damage accumulation and actualy DNA methylation changes/epigenetic drifting).Thus, we have to 'maintain' that 'early Young state' if we wish to beat 120, 130...and make it to 200. And that means a longer 'initial period of youth' will 'post-pone' the arrival of 'downward-slope'. ONce you get to that slope it's over. That's why age must be maintained 'young' from an early age - and onward till the very last day - and thus, 'push back' the changes of late-aging. If we could push back that slope up to a 120 (meaning at 100 we would be about 50 biologically), then yes, 200 we would make it and even over that.

Posted by: CANanonymity at December 5th, 2016 9:28 PM

PS: It's a misconception and erroneous anomaly (MLSP does not exist per say it's just a barometer to give a general 'known' maximum lifespan - same species Beat their own MLSP in the lab and show that aging can be Totally changed) to say if we keep on being healthy - it is impossible to go over 120 - that,'s totally false. It all dépendent and incumbent on the initial period of the life (if we do not get special anti-aging therapies) - how long were you 40, how long were you 50, how long were you 60 biologically ? Are you biologically younger or older than your chronological age ? SENS therapies, epigenetic/methylation reprogramming and other nanotechnologies of the future have the power, when combined, to Revert (Rejuvenation) back to 20 year old and thus would, theoretically allow anyone to do looping back to a younger biological and epigenetic phenotype state (equalling infinite lifespan (on paper), in practice I doubt it because there are so many factors that regulate aging (like the sempiternel damage accumulation problem); but it would definitely allow someone reaching the human MLSP)).
The gist of it, is the Younger the Better, The Earlier/Sooner(est) you start 'keeping Young biologically' the Highest chances you reach human MLSP - and you Surpass it (for example, that has been shown in C.Elegans whom lived 10-fold longer by genetic manipulation, beating their MLSP 10 times, and yes, you guessed it - these mutants were - Very Young Biologically - for a much longer time (they accumulated no lipofuscin in their intestinal compartment like the 'regular ones who got old fast' - this proved beyond a doubt that aging can be modulated/that 'staying biologicall Young is the only way to immortality/lifespan extension' and it's only a matter of time before we make a immortal C.Elegans or Mice).

Posted by: CANanonymity at December 5th, 2016 10:30 PM

The pattern of neuron firing seems to be the essence of memory. Over time, the pattern degrades and eventually the pattern becomes very difficult to fire. One can use Ebbinghaus-like review (see Supermemo or other memorization regimes) or something less programmatic (like conversation) to increase the likelihood of the pattern firing.

What you choose to review changes who you and how the original experience affects you. Numerous scientific studies show how plastic memories are when they are recalled, and how traumatic memories can be lessened by review and purposeful modification.

Those who claim perfect autobiographical memory sometimes say they are tormented by isolated experiences of the past: being able to choose which memories to review might have a large effect on your personality, even if you could recall everything.

Posted by: MikeMaging at December 7th, 2016 4:35 PM

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