Synapse Strengthening is Way, Way Too Slow to Explain Instant Learning

The Kavli Foundation is a foundation founded by millions of dollars in grants from the late Fred Kavli. The foundation issues science prizes and science grants. One of its semi-annual prizes is in neuroscience. An earlier post on this blog described the bunk and misleading information that occurred when the 1 million dollar Kavli Prize in neuroscience was announced in 2024.  Recently the Kavli Prize was awarded to neuroscientists involved in work on protein synthesis in dendrites: Oswald Steward, Christine Holt, Kelsey Martin and Erin Schuman. The announcement of the prize award makes no mention of learning or memory, merely stating this: "THE KAVLI PRIZE IN NEUROSCIENCE IS AWARDED TO: Christine Holt, Kelsey Martin, Erin Schuman and Oswald Steward for the discovery of local protein translation in neurons and establishing its importance for brain development and plasticity."  

The same page has a video announcement, where someone very incorrectly makes the utterly groundless claim at the 16:32 mark that this research "came to transform our understanding of how the brain develops, adapts, and stores information." Neuroscientists have no real understanding of how a brain can store learned information, and the vague hand-waving simple-slogan "theory" of synapse strengthening is no such understanding. The same authority makes the groundless boast at the 18:15 mark that the work of Kelsey Martin "helps explain how learning and memory are stored in the brain," a boast that has no basis in truth. Neuroscientists do not have any understanding of how any learning or memory could be stored in the brain, and microscopic examination of brain tissue has never produced the slightest trace of anything learned or experienced or memorized. 

A Simons Foundation page incorrectly claims this was a reward for memory research, stating, "This year’s Kavli Prize in Neuroscience celebrates research on how neurons form and modify neural connections to enable processes such as learning and memory." That goes beyond any claim made in the written prize announcement statement, and we certainly do not know that "neural connections...enable processes such as learning and memory," which is a mere groundless dogma of neuroscientists. 

A press release by the University of California announcing this prize gives us bunk and misleading information related to this topic. We have a press release with this paragraph, preceded by the bogus header of "Transformative discoveries." The paragraph veers into falsehood at its end:

"For decades, scientists believed that proteins needed by neurons were produced primarily in the cell body. Steward’s groundbreaking electron microscopy studies revealed protein-producing machinery located near synapses, which is where cells make connections with each other, demonstrating that neurons can manufacture proteins locally where they’re needed. His subsequent research defined the mechanisms of messenger RNA transport from the nucleus and selective localization at active synapses, creating a new understanding of brain plasticity, learning and memory." 

The described research produced no actual progress in understanding learning or memory. Neuroscientists claim that protein synthesis is required for learning and memory, but their claims about this do not hold up to scrutiny, because of two reasons:

(1) All brain proteins have short lifetimes, typically less than two weeks. The proteins in the brain and its synapses are constantly being replaced. There is no credibility in attempts to explain memory formation by referring to "synapse strengthening" occurring by protein synthesis. Old humans can remember well things that happened 50 years ago, and the span of 50 years is a length of time 1000 times greater than the average lifetime of the proteins in synapses. Individual synapses cannot last for years, partially because they are connected to dendritic spines that do not last for years, and typically last for less than a few months. 

(2) Humans can learn things instantly, much faster than the time required for synapse strengthening by protein synthesis, which is at least several minutes. When someone is informed of the death of their child or parent, that person instantly forms a new memory that lasts for the rest of his life. 

It seems, therefore, that mere research into protein synthesis can never correctly be described as research that helps understand how memories form. A press release at the University of Cambridge has a paragraph that describes the research awarded the Kavli prize in neuroscience, and attempts to create some impression that a little progress has occurred related to understanding memory. But the narrative it tells is a false one, and the paragraph starts out with a misleading first sentence. The paragraph is below:

"Scientists long struggled to explain how the human brain can be so efficient – we can ultimately learn things in mere minutes. The proteins needed to enable the process in brain cells simply take too long to travel from the body of the brain cell, the neuron, to where the synapses – tiny junctions between neurons that allow them to communicate with each other or other cells – actually happen. But research spanning decades by this year’s laureates – Oswald Steward, Erin Schuman, Kelsey Martin and Christine Holt – has solved the mystery. Rather than the proteins being created in the cell body, as was previously thought, they can be produced directly on site close to where the all-important synapses happen; in the branches of the neurons appendages, called dendrites and axons. The discovery has led to a new understanding of how the brain works – and offers insights into how this process goes wrong in a range of brain disorders."

The narrative is bogus. It begins with the very misleading insinuation that human memory creation requires minutes. To the contrary, humans can form new memories instantly. So there was never a "problem of explaining how memories can be created in mere minutes." The problem was a much more difficult one: the problem of explaining how humans can create complex new memories instantly. 

The real problem (the problem of how humans can create complex new memories instantly) is not at all solved (or even appreciably reduced) by postulating that proteins are synthesized in the dendrites of cells, and are then used to bulk up synapses. The diagram below may help you understand why:

What difference would it make (under the theory that memories are stored in synapses) if some proteins are synthesized in dendrites  (the rather finger-like projections you see in the diagram above) rather than in the cell body of a neuron (surrounding the largest yellow circle in the diagram above)? Very little difference indeed. There might be a very slight decrease in the amount of time it would take newly synthesized proteins to travel to a synapse. But the difference would be small. 

A particular type of protein molecule is created by this process:

(1) Somehow the right position is found in human DNA, allowing a reading to occur from a small fraction of the DNA (called a gene), with the information being transferred into a messenger RNA molecule. How that messenger RNA is ever able to find the right gene is a mystery. The gene stores symbolic information describing the amino acid sequence of some particular protein molecule. This reading is called transcription, and occurs at a rate between 10 and 50 nucleotides per second. Since an average protein requires between 1200 and 1500 nucleotides to be read from a gene for the transcription required by the protein to occur, the transcription of a protein requires somewhere between 25 seconds and several minutes.  

(2) Somehow the messenger RNA molecule is translated into a chain of amino acids. This process is called translation, and is thought to occur at a rate of about 5 amino acids per second. Because the average protein used in synapses has about 450 amino acids, this translation must take an average of roughly 90 seconds. 

(3) Somehow (in a way that is not understood at all) that amino acid sequence quickly converts into a three-dimensional protein molecule that is folded.  This process is called protein folding. How it occurs is a mystery called the protein folding problem, which has not yet been solved. A year 2026 paper states, "The protein folding problem remains unsolved."

The Google Gemini infographic below illustrates this process:

To calculate the time required for a new protein to be created and then travel to a synapse as part of some synapse strengthening imagined to be part of a theoretical storage of memory in synapses, assuming protein synthesis in the main body of a neuron, you would need to calculate all of these different factors:

(1) The time needed for some sensory signal to travel to some neuron so that protein synthesis is somehow triggered (no one has any understanding of how sensory information could have any relation to when or where protein synthesis occurs). 

(2) The time required for a cell or messenger RNA molecule to find the right position in DNA  from which to read the amino acid sequence needed to make the new protein molecule of a particular type. Given that DNA stores the amino acid sequences of more than 20,000 different proteins, without any kind of indexing system or sorting system,  this is kind of a "finding a needle in a haystack" situation. The mere "finding the right location to read" part should take very significant time.

(3) The time needed for the reading to occur once the right location had been found, resulting in a messenger RNA molecule matching the gene read. This is the speed of transcription.  Transcription occurs at a rate between 10 and 50 nucleotides per second. Since an average protein requires between 1200 and 1500 nucleotides to be read from a gene for the transcription required for that protein to occur, the transcription of a protein requires somewhere between 25 seconds and several minutes.  

(4) The time required for protein translation, by which the messenger RNA molecule is converted into an amino acid sequence, a specific chain of hundreds of amino acids. Translation in humans is thought to occur at a rate of about 5 amino acids per second. Because the average protein used in synapses has about 450 amino acids, this translation must take an average of roughly 90 seconds.

(5) The time required for there to occur the mysterious process of protein folding, by which a chain of amino acids forms into the 3D shape needed for a functional protein molecule.  

(6) The time needed for a newly synthesized protein molecule to travel from the neuron to the synapse. 

(7) The time needed for this newly synthesized protein molecule to somehow be integrated into the synapse, so that the synapse ends up being strengthened.

The total length of time required for this series of events would be at least three minutes, and very probably many minutes. You only slightly reduce the total length of time required for the totality of all of these things if you assume some protein synthesis going on in dendrites. That reduces the time required for only one of the items in the list above, leaving all of the other factors being just as slow as before.  

Because synapse strengthening requires a series of events that would require a total time of at least three minutes, the synaptic theory of memory (that memories are stored by synaptic strengthening) totally fails to account for the indisputable reality that humans can form permanent new memories instantly. Very rich organizations such as the Kavli Foundation can issue all of the triumphal million-dollar prize announcements that they wish. But the fact is that scientists do not have any credible explanation for how there could occur in a brain human learning which occurs instantly. The most reasonable alternative here is to discard the dogma that memory formation is a brain process. 

Synapses have not the slightest resemblance to a memory storage device. The idea that human memory can be explained by some mere idea of synapse strengthening is one that future scientists will look back on with scorn, the way today's scientists look back scornfully at 18th-century claims that health could be improved by attaching leeches to the arm. Strengthening isn't storage. 

Exhibit C That Neuroscientists Have No Understanding of How a Memory Could Form or Last in a Brain

 In 2020 on this site I published a post entitled "Exhibit A Suggesting Scientists Don't Understand How a Brain Could Store a Memory." In 2023 I published on this site a post entitled "Exhibit B That Scientists Have No Understanding of a Physical Basis of Human Memory." Now it is time for Exhibit C on this topic. 

I recently discovered a web site called The Transmitter (www.thetransmitter.org) that mainly covers neuroscience research and neuroscience theory. When read in a critical manner, an article on the last site serves to powerfully remind us that neuroscientists lack any such thing as either a real theory of memory storage or a real theory of life-long memory persistence. When scientists speak on these topics, they offer only the flimsiest catchphrases, soundbites that have the weight of soap bubbles. 

The title of the article is "What makes memories last—dynamic ensembles or static synapses?" The reference to "static synapses" is a very misleading one. Everything we know about synapses tells us that a synapse is an unstable thing that cannot last for years.

We read a neuroscientist (Jason Shepherd) making these claims:

"The debate over how information is stored in the brain is often represented as one between two extremes. One viewpoint posits that learning induces changes in gene expression that ultimately alter the structure and function of specific synapses within the physical memory circuit, or engram. These molecular changes at the synapses can remain stable for the lifetime of the memory. The other viewpoint claims that information is represented not in a specific set of cells or synapses but rather across a loose set of cells and circuits that 'drift' over time."

The narrative of two rival theories is a false one. The situation is really "no theory at all" but merely empty, vacuous sound bites and slogans such as "synapse strengthening," which may differ from one speaker to the next. The claim above that "molecular changes at the synapses can remain stable for the lifetime of the memory" is something entirely contrary to fact. We know that human memories can persist for more than 50 years. Synapses, on the other hand, are "shifting sands" type of things that are dramatically unstable. The proteins that make up synapses have an average lifetime of less than 3 weeks.  Synapses are connected to dendritic spines, which are known to have short lifetimes, not lasting for years. Remarkably synapses are built of proteins which have an average lifetime about 1000 times shorter than the maximum length of time that humans can remember things. This discrepancy is one of very many reasons why the idea that memories are stored in synapses is one of the most nonsensical ideas that scientists have ever advanced. 

Notice well the utter emptiness of what is discussed as an alternative to the utterly-vacuous-by-itself idea that memories are formed by "synapse strengthening." The alternative is presented as the idea that " information is represented not in a specific set of cells or synapses but rather across a loose set of cells and circuits that 'drift' over time." That's an utterly vague, vacuous, empty sound bite that is as much  of an empty soap bubble as the equally empty notion of "synapse strengthening." Not the slightest bit of weight is added by the next two sentences:

"In this view, the cells that initially encoded an experience are not the same set of cells that actually store the information. Indeed, the precise set of cells do not matter in this framework—the information for a specific memory is instead decoded from the computational space of firing patterns across a set of cells."

As some type of attempt to explain stable memories that can last for 50 years, this idea is as supremely goofy as the idea that memories that last for 50 years are stored in the "shifting sands" of synapses. The "firing patterns" in the brain are ever-changing. Trying to claim that stable memories are stored in "firing patterns" is as goofy as the claim that your tax records and childhood photos are stored in the wind patterns around your house. 

Shepherd gives us some "rival cases" paragraphs. Under a heading of "The case for memory engrams," he makes some untrue statements. He states this:

" In experiments that used this approach, light-sensitive receptors were expressed only in the cells active during learning. Shining a light to activate these cells days or even weeks after training resulted in the recall of a memory without any external experience or cue. This remarkable observation set the stage for the idea that 'engram' neurons that encode learning are sufficient to store and recall a memory."

No robust research of any such type ever occurred.  Shepherd is simply repeating a groundless achievement legend of neuroscientists. When you read the papers that claim to have done such things, you will always find that they were junk-science studies guilty of multiple types of Questionable Research Practices such as the use of way-too-small study group sizes, and the use of unreliable techniques for attempting to judge recall in rodents, such as the unreliable method of trying to judge "freezing behavior."

Under the heading of "the representational drift perspective," Shepherd presents nothing in the way of any evidence. We get only the most roundabout hand-waving. 

Shepherd then asks eight neuroscientists for their opinions on the topic of memory storage by a brain. Shepherd follows a senseless procedure.  A good open question to ask would be something like this:

"Do you have a good, credible theory of how a brain could store memories, and how memories could persist a lifetime? If so, describe the best evidence for such a theory, and tell us how confident you are that such a theory is true."

And a good follow-up question would be questions like this:

• "Are there any physical factors in the brain that argue against such a theory? Explain how such a theory could really allow 50-year memory storage despite all the molecular and structural turnover in the brain."
• "Trying to be precise, and avoiding vague language, can you explain exactly how a detailed memory could be stored under such a theory? For example, exactly how could a brain store a page of text that someone had memorized, so that the person could retrieve that whole page?"
• "Under such a theory, how would it be possible for someone to instantly recall lots of relevant detailed information after seeing a single face or hearing a single name? For example, how could someone ever recite a paragraph describing the life of Abraham Lincoln after merely hearing his name? How could information about Lincoln stored in a brain ever be found quickly enough to allow instant recall?"

But Shepherd asks no such challenging questions to his eight neuroscientists. Instead he asks each of them the softest of softball questions. Each neuroscientist is asked these questions:

• "Is information stored in the brain at the level of cells (or circuits) or at the level of synapses?"
• "Can we reconcile observations that show distinct engram circuits seem to store memories versus observations that show the neuronal activity of these memory engram drifts?"
• "What experimental data would be helpful to reconcile these observations to help bring these theories together?"

The first question is a classic example of a stupid "either/or" question in which someone is asked to choose between two alternatives, neither of which is credible. The question is as stupid as asking, "Are UFOs spaceships from the planet Mars or spaceships from the planet Venus?" The second question is one with a false premise embedded within it. It is not true that there are "observations that show distinct engram circuits seem to store memories." Microscopic examination of brain tissue has never shown the slightest trace of anything anyone has learned or experienced. The third question is the type of question you might ask neuroscientists when they don't have any good evidence to back up their dogmas. Rather than asking them to tell about what evidence backs up their claims, you might ask them to fantasize about what type of future observations they might make that might back up their theories. 

None of the eight questioned neuroscientists has anything of any substance to offer in response to the questions. The first question at least offers an invitation for someone to start expounding about any theory he may have of neural memory storage. We get no impressive quotes in response to such a question. We get only the wobbliest hand-waving that makes the people giving the answers sound very empty-handed. 

• Andre Fenton of New York University has nothing of any substance to say. He says "information is not stored in any single element," and "it may not be practically possible to separate the process of storage from the access," both of which suggest that he has no understanding of how a brain could store a memory. People who understand how some type of information is stored do not say such things. 
• Loren Frank of the University of California gives us no impression that he understands how a brain could store a memory. He says, "It might be that changes in gene expression lead to changes in activity levels, although at the moment we really don’t understand the scope of these changes." He offers only the vaguest hand-waving, with a mention of the hippocampus. We have an example of the vaguest and most conceptually empty hand-waving in this statement by Frank: "Focusing on memories for the events of daily life, our current conception is that the events themselves drive activity across the brain, engaging specific neurons whose activity represents the various sights, sounds, smells and feelings that are part of the experience." 
• Kari Hoffman of Vanderbilt University also offers only the vaguest handwaving, an example being this statement: "I would submit that much of the heavy lifting is done at both the synaptic and circuit/ensemble level. Which levels dominate depends on factors such as memory type, when information was acquired and how it is integrated with the existing structures, themselves reflecting changes from earlier experiences. " Another statement by her indicates she has no real understanding on this topic: "That said, we may need to be careful in using the term 'these memories' or 'these memory engrams.'  Such terms suggest that experience creates biological bins to hold discrete memories, that memories exist as entities that are created 'de novo,' and that neural modifications must reside at only one level, all of which are positions that are not or may not be true." 
• Yingxi Lin of the University of Texas says, "It is, however, too early to say that those cells and synapses are sites of stored memory per se, as they may simply function to gain access to the memory."  She also says, " It is also possible that there aren’t specific sites for memory storage; cells and synapses may be part of a brain-wide code for memory expression." She seems to have no understanding of how a brain could store a memory. 
• Cian O'Donnell of Ulster University sounds like a weak scholar of neuroscience when he states, "The field has held synaptic plasticity up as the main mechanism for information storage in the brain for several decades now, and I haven’t heard any good reasons to start doubting it yet." There are very many such reasons, such as the fact that synapses are composed of proteins with very short lifetimes, the fact that synapses bear no resemblance to any system for writing or reading information, the fact that synapses do not reliably transmit information, and that synapses are connected to dendritic spines that are unstable and do not last for years. Nothing O'Donnell says makes him sound like anyone with an understanding of how a brain could store memories. 
• Timothy O'Leary of Cambridge University (not to be confused with the late Timothy Leary of Harvard) says nothing to inspire any confidence that he has any understanding of how a brain could store a memory. All he does is to reveal that he fell "hook, line and sinker" for bad neuroscience experiments using way-too-small study group sizes and the utterly unreliable technique of trying to judge recall by judging "freezing behavior." 
• Tomas Ryan of Trinity College also says  says nothing to inspire any confidence that he has any understanding of how a brain could store a memory. He engages in the emptiest of hand-waving when he says this: "It seems to me that the plausible level for the storage of long-term memories is in the topography of the connectome. So, the information is engraved through stable changes in the brain’s microanatomical circuit." The "connectome" he refers to is the collection of all synapses. But synapses are not stable, but the opposite of stable. So his claim makes no sense. 
• The last of the eight neuroscientists is Evan Schaffer of the School of Medicine at Mount Sinai. He states this: "As a consequence, I don’t think information can be stored in cells or synapses in the hippocampus in a way that is stable over a lifetime. In other parts of the brain, this may not be the case." No, actually, there is no credible storage place for memories in the brain, either in the hippocampus or anywhere else. Not sounding like anyone who understands how a brain could store memories, Schaffer also sounds like a poor student of human mental performance. Most misleadingly, he tries to suggest that humans may not be able to remember things well for weeks. He says, "On a timescale of a few days, memories seem pretty stable. On a timescale of a few weeks, there’s less evidence for stability." To the contrary, there is abundant evidence that humans can very well remember things for decades. To give one of endless examples I could cite, every opera fan knows that various opera stars are able to perfectly remember over many years the very many notes and words that make up particular opera roles. Placido Domingo, for example, performed more than 150 opera roles, many of which required singing for hours on the stage, from memory. 

Finally in the article we have a summing up by Shepherd, who sounds just as empty-handed and theory-lacking as the eight experts he has interviewed. He says this:

"Finally, neuroscientists must do a better job of defining their terms. What is 'information,' and how is it 'represented' in the brain? What is an engram?"

The title of the article was "What makes memories last—dynamic ensembles or static synapses?" I re-read all of the answers to see whether anyone addressed the issue of how memories could last in a brain long enough to persist for decades. Not one of the eight neuroscientists even addressed the issue. Not one of them advanced any theory as to how memories could persist for decades. Not one of them advanced even a hypothesis about such a topic.  The issue of how memories could last for decades was simply ignored by the eight neuroscientists, none of whom had either a real theory of memory storage to advance, nor any theory of the life-long preservation of memory.  We certainly did not get any such thing when we got this piece of fantasy by Tomas Ryan:

"It seems to me that the plausible level for the storage of long-term memories is in the topography of the connectome. So, the information is engraved through stable changes in the brain’s microanatomical circuit." 

Engraved? No such engraving occurs in the brain. Nothing in a brain bears any resemblance to a system or component for writing learned information. There is zero evidence that anything bearing the slightest resemblance to engraving occurs in the brain. We see no "engraved" neurons, no "engraved" synapses, and no "engraved" dendritic spines.  Everything that has been learned about synapses shouts that a synapse cannot have any such thing as stable changes, in the sense of changes that last permanently for decades. The proteins that make up synapses have average lifetimes of less than a few weeks. And synapses are attached to dendritic spines that are known to have short lifetimes, dendritic spines that do not last for years. 

A 2019 paper documents a 16-day examination of synapses, finding "the dataset contained n = 320 stable synapses, n = 163 eliminated synapses and n = 134 formed synapses."  That's about a 33% disappearance rate over a course of 16 days. The same paper refers to another paper that "reported rates of [dendritic] spine eliminations in the order of 40% over an observation period of 4 days."  A paper studying the lifetimes of dendritic spines in the cortex states, "Under our experimental conditions, most spines that appear survive for at most a few days. Spines that appear and persist are rare." The rare persistence referred to was only a persistence of a few months. 

The 2023 paper here gives the graph below showing the decay rate of the volume of dendritic spines. It is obvious from the graph that they do not last for years, and mostly do not even last for six months. 

Page 278 of the same paper says, "Two-photon imaging in the Gan and Svoboda labs revealed that spines can be stable over extended periods of time in vivo but also display genesis (generation) and elimination (pruning) at a frequency of 1–4% per week." Something vanishing at a rate of 2% per week will be gone within a year. 

Below are some quotes by scientists and doctors who spoke candidly about brains and memory storage, rather than engaging in the kind of bluffing that went on from the people mentioned above:

• "Direct evidence that synaptic plasticity is the actual cellular mechanism for human learning and memory is lacking." -- 3 scientists, "Synaptic plasticity in human cortical circuits: cellular mechanisms of learning and memory in the human brain?" 
• "The fundamental problem is that we don't really know where or how thoughts are stored in the brain. We can't read thoughts if we don't understand the neuroscience behind them." -- Juan Alvaro Gallego, neuroscientist. 
• "The search for the neuroanatomical locus of semantic memory has simultaneously led us nowhere and everywhere. There is no compelling evidence that any one brain region plays a dedicated and privileged role in the representation or retrieval of all sorts of semantic knowledge."  Psychologist Sharon L. Thompson-Schill, "Neuroimaging studies of semantic memory: inferring 'how' from 'where' ".
• "How the brain stores and retrieves memories is an important unsolved problem in neuroscience." --Achint Kumar, "A Model For Hierarchical Memory Storage in Piriform Cortex." 
• "We are still far from identifying the 'double helix' of memory—if one even exists. We do not have a clear idea of how long-term, specific information may be stored in the brain, into separate engrams that can be reactivated when relevant."  -- Two scientists, "Understanding the physical basis of memory: Molecular mechanisms of the engram."
• "There is no chain of reasonable inferences by means of which our present, albeit highly imperfect, view of the functional organization of the brain can be reconciled with the possibility of its acquiring, storing and retrieving nervous information by encoding such information in molecules of nucleic acid or protein." -- Molecular geneticist G. S. Stent, quoted in the paper here. 
• "Up to this point, we still don’t understand how we maintain memories in our brains for up to our entire lifetimes.”  --neuroscientist Sakina Palida.
• "The available evidence makes it extremely unlikely that synapses are the site of long-term memory storage for representational content (i.e., memory for 'facts'’ about quantities like space, time, and number)." --Samuel J. Gershman,  "The molecular memory code and synaptic plasticity: A synthesis."
• "Synapses are signal conductors, not symbols. They do not stand for anything. They convey information bearing signals between neurons, but they do not themselves convey information forward in time, as does, for example, a gene or a register in computer memory. No specifiable fact about the animal’s experience can be read off from the synapses that have been altered by that experience.” -- Two scientists, "Locating the engram: Should we look for plastic synapses or information- storing molecules?
• " If I wanted to transfer my memories into a machine, I would need to know what my memories are made of. But nobody knows." -- neuroscientist Guillaume Thierry (link). 
• "While a lot of studies have focused on memory processes such as memory consolidation and retrieval, very little is known about memory storage" -- scientific paper (link).
• "While LTP is assumed to be the neural correlate of learning and memory, no conclusive evidence has been produced to substantiate that when an organism learns LTP occurs in that organism’s brain or brain correlate."  -- PhD thesis of a scientist, 2007 (link). 
• "Memory retrieval is even more mysterious than storage. When I ask if you know Alex Ritchie, the answer is immediately obvious to you, and there is no good theory to explain how memory retrieval can happen so quickly." -- Neuroscientist David Eagleman.
• "How could that encoded information be retrieved and transcribed from the enduring structure into the transient signals that carry that same information to the computational machinery that acts on the information?....In the voluminous contemporary literature on the neurobiology of memory, there is no discussion of these questions."  ---  Neuroscientists C. R. Gallistel and Adam Philip King, "Memory and the Computational Brain: Why Cognitive Science Will Transform Neuroscience,"  preface. 
• "The very first thing that any computer scientist would want to know about a computer is how it writes to memory and reads from memory....Yet we do not really know how this most foundational element of computation is implemented in the brain."  -- Noam Chomsky and Robert C. Berwick, "Why Only Us? Language and Evolution," page 50. 
• "When we are looking for a mechanism that implements a read/write memory in the nervous system, looking at synaptic strength and connectivity patterns might be misleading for many reasons...Tentative evidence for the (classical) cognitive scientists' reservations toward the synapse as the locus of memory in the brain has accumulated....Changes in synaptic strength are not directly related to storage of new information in memory....The rate of synaptic turnover in absence of learning is actually so high that the newly formed connections (which supposedly encode the new memory) will have vanished in due time. It is worth noticing that these findings actually are to be expected when considering that synapses are made of proteins which are generally known to have a short lifetime...Synapses have been found to be constantly turning over in all parts of cortex that have been examined using two-photon microscopy so far...The synapse is probably an ill fit when looking for a basic memory mechanism in the nervous system." -- Scientist Patrick C. Trettenbrein, "The Demise of the Synapse As the Locus of Memory: A Looming Paradigm Shift? (link).
• "Most neuroscientists believe that memories are encoded by changing the strength of synaptic connections between neurons....Nevertheless, the question of whether memories are stored locally at synapses remains a point of contention. Some cognitive neuroscientists have argued that for the brain to work as a computational device, it must have the equivalent of a read/write memory and the synapse is far too complex to serve this purpose (Gaallistel and King, 2009; Trettenbrein, 2016). While it is conceptually simple for computers to store synaptic weights digitally using their read/write capabilities during deep learning, for biological systems no realistic biological mechanism has yet been proposed, or in my opinion could be envisioned, that would decode symbolic information in a series of molecular switches (Gaallistel and King, 2009) and then transform this information into specific synaptic weights." -- Neuroscientist Wayne S. Sossin (link).
• "We take up the question that will have been pressing on the minds of many readers ever since it became clear that we are profoundly skeptical about the hypothesis that the physical basis of memory is some form of synaptic plasticity, the only hypothesis that has ever been seriously considered by the neuroscience community. The obvious question is: Well, if it’s not synaptic plasticity, what is it? Here, we refuse to be drawn. We do not think we know what the mechanism of an addressable read/write memory is, and we have no faith in our ability to conjecture a correct answer."  -- Neuroscientists C. R. Gallistel and Adam Philip King, "Memory and the Computational Brain Why Cognitive Science Will Transform Neuroscience."  page Xvi (preface). 
• "Current theories of synaptic plasticity and network activity cannot explain learning, memory, and cognition."  -- Neuroscientist Hessameddin Akhlaghpourƚ (link). 
• "It remains unclear where and how prior knowledge is represented in the brain." -- A large team of scientists, 2025 (link). 
• "How memory is stored in the brain is unknown." -- Research proposal abstract written by scientists, 2025 (link). 
• "We don’t know how the brain stores anything, let alone words." -- Scientists David Poeppel and, William Idsardi, 2022 (link).
• "If we believe that memories are made of patterns of synaptic connections sculpted by experience, and if we know, behaviorally, that motor memories last a lifetime, then how can we explain the fact that individual synaptic spines are constantly turning over and that aggregate synaptic strengths are constantly fluctuating? How can the memories outlast their putative constitutive components?" --Neuroscientists Emilio Bizzi and Robert Ajemian (link).
• "After more than 70 years of research efforts by cognitive psychologists and neuroscientists, the question of where memory information is stored in the brain remains unresolved." -- Psychologist James Tee and engineering expert Desmond P. Taylor, "Where Is Memory Information Stored in the Brain?"
• "There is no such thing as encoding a perception...There is no such thing as a neural code...Nothing that one might find in the brain could possibly be a representation of the fact that one was told that Hastings was fought in 1066." -- M. R.  Bennett, Professor of Physiology at the University of Sydney (link).
• "No sense has been given to the idea of encoding or representing factual information in the neurons and synapses of the brain." -- M. R. Bennett, Professor of Physiology at the University of Sydney (link).
• ""Despite over a hundred years of research, the cellular/molecular mechanisms underlying learning and memory are still not completely understood. Many hypotheses have been proposed, but there is no consensus for any of these."  -- Two scientists in a 2024 paper (link). 
• "We have still not discovered the physical basis of memory, despite more than a century of efforts by many leading figures. Researchers searching for the physical basis of memory are looking for the wrong thing (the associative bond) in the wrong place (the synaptic junction), guided by an erroneous conception of what memory is and the role it plays in computation." --Neuroscientist C.R. Gallistel, "The Physical Basis of Memory," 2021.
• "To name but a few examples, the formation of memories and the basis of conscious  perception, crossing  the threshold  of  awareness, the  interplay  of  electrical  and  molecular-biochemical mechanisms of signal transduction at synapses, the role of glial cells in signal transduction and metabolism, the role of different brain states in the life-long reorganization of the synaptic structure or  the mechanism of how  cell  assemblies  generate a  concrete  cognitive  function are  all important processes that remain to be characterized." -- "The coming decade of digital brain research, a 2023 paper co-authored by more than 100 neuroscientists, one confessing scientists don't understand how a brain could store memories. 
• "The human brain isn’t really empty, of course. But it does not contain most of the things people think it does – not even simple things such as ‘memories’....We don’t create representations of visual stimuli, store them in a short-term memory buffer, and then transfer the representation into a long-term memory device. We don’t retrieve information or images or words from memory registers. Computers do all of these things, but organisms do not." -- Robert Epstein,  senior research psychologist, "The Empty Brain." 
• "Despite recent advancements in identifying engram cells, our understanding of their regulatory and functional mechanisms remains in its infancy." -- Scientists claiming erroneously in 2024 that there have been recent advancements in identifying engram cells, but confessing there is no understanding of how they work (link).
• "Study of the genetics of human memory is in its infancy though many genes have been investigated for their association to memory in humans and non-human animals."  -- Scientists in 2022 (link).
• "The neurobiology of memory is still in its infancy." -- Scientist in 2020 (link). 
• "The investigation of the neuroanatomical bases of semantic memory is in its infancy." -- 3 scientists, 2007 (link). 
• "Currently, our knowledge pertaining to the neural construct of intelligence and memory is in its infancy." -- Scientists, 2011 (link). 
•  "Very little is known about the underlying mechanisms for visual recognition memory."  -- two scientists (link). 
• "Conclusive evidence that specific long-term memory formation relies on dendritic growth and structural synaptic changes has proven elusive. Connectionist models of memory based on this hypothesis are confronted with the so-called plasticity stability dilemma or catastrophic interference. Other fundamental limitations of these models are the feature binding problem, the speed of learning, the capacity of the memory, the localisation in time of an event and the problem of spatio-temporal pattern generation."  -- Two scientists in 2022 (link). 
• "The mechanisms governing successful episodic memory formation, consolidation and retrieval remain elusive,"  - Bogdan Draganski, cogntive neuroscientist (link). 
• " The mechanisms underlying the formation and management of the memory traces are still poorly understood." -- Three scientists in 2023 (link). 
• "The underlying electrophysiological processes underlying memory formation and retrieval in humans remains very poorly understood." --  A scientist in 2021 (link). 
• "As for the explicit types of memory, the biological underpinning of this very long-lasting memory storage is not yet understood." -- Neuroscientist Cristina M. Alberini in a year 2025 paper (link). 

Microscopes Will Never Find the Slightest Trace of Learned Information in a Human Brain

A recent story at the LiveScience.com site has the title "Could we ever retrieve memories from a dead person's brain?" The story has many  inaccurate claims, and fails to tell us the most important facts that are relevant to the question being considered. The subtitle of the article makes this claim: "Neuroscientists have identified the physical locations where memories are stored in the brain."  No, they have not done any such thing, and the article fails to present any good evidence that any such thing was done. 

We have this claim about a method to retrieve a memory from a brain:

"With today's technology, retrieving memories might go something like this. First, identify the set of brain cells, or neurons, that encoded a specific memory in the brain and understand how they are connected. Then, activate those neurons to create an approximate neural network, a machine learning algorithm that mimics the way the brain works."

This does not make any sense as an idea about how one would go about trying to start to read a memory from a brain. The first step in such a process would be to use microscopes to look for any speck of a trace of learned information in a brain. No one has ever succeeded in doing any such thing. Microscopic examination of brain tissue has never revealed a single word anyone ever learned. Microscopic examination of brain tissue has never revealed a single letter or character of anything anyone previously learned, and has never revealed a single pixel (an image dot) of anything anyone ever previously saw. Neural networks are a misnamed type of computer technology that do not actually mimic the brain and its physical shortfalls. 

We have quotes by a neuroscientist (Don Arnold) doing some vague hand-waving and speaking as if he knew things he does not actually know. We read,  "Memories are encoded by groups of neurons, Arnold said." That's the kind of vacuous, vague hand-waving that someone may use when he lacks any actual knowledge of how a brain could store memories.  When people make big important-sounding claims that are not well-supported by evidence, they typically speak in a kind of vague, hand-waving way.  For example, when asked where there existed the weapons of mass destruction that the US claimed were in Iraq before invading it in 2003, US defense secretary Donald Rumsfeld said this:

"We know where they are. They're in the area around Tikrit and Baghdad and east, west, south and north somewhat."

Such weapons of mass destruction were never found in Iraq in 2003 or in the next twenty years. 

Reminding me of the Rumsfeld statement, the LiveScience article claims that long-term memories are formed in the hippocampus, a claim not backed up any robust evidence. The main research paper on the hippocampus and memory is the paper "Memory Outcome after Selective Amygdalohippocampectomy: A Study in 140 Patients with Temporal Lobe Epilepsy." That paper gives memory scores for 140 patients who almost all had the hippocampus removed to stop seizures.  Using the term "en bloc" which means "in its entirety" and the term "resected" which means "cut out," the paper states, "The hippocampus and the parahippocampal gyrus were usually resected en bloc."  The "Memory Outcome after Selective Amygdalohippocampectomy" paper does not use the word "amnesia" to describe the results. That paper gives memory scores that merely show only a modest decline in memory performance.  The paper states, "Nonverbal memory performance is slightly impaired preoperatively in both groups, with no apparent worsening attributable to surgery."  In fact, Table 3 of the paper informs us that a lack of any significant change in memory performance after removal of the hippocampus was far more common than a decline in memory performance, and that a substantial number of the patients improved their memory performance after their hippocampus was removed. 

The LiveScience article tells us, "Other parts of the brain store different aspects of a memory, like emotions and other sensory details, according to the Cleveland Clinic." We are referred to a page on some web site of the Cleveland Clinic that has no named author, and is the kind of article that you might get if you asked ChatGPT about how memory works. That Cleveland Clinic page does not actually make the claim that the LiveScience article attributes to it. The Cleveland Clinic does not claim that different aspects of a memory are stored in different places, but merely claims that other parts of a brain "participate in memory processes."

The LiveScience article then makes a false claim, repeating a groundless achievement legend. It states this:

"Neuroscientists have identified engrams in the hippocampuses of mouse brains. For instance, in a 2012 study published in the journal Nature, researchers found the specific brain cells associated with a memory of an experience that induced fear." 

No, there does any exist any robust evidence for engrams (neural storage places of memories) in any animal.  The paper the LiveScience article links to is the 2012 paper “Optogenetic stimulation of a hippocampal engram activates fear memory recall.” That is a very low-quality paper guilty of several bad examples of Questionable Research Practices. We see in Figure 3 of that paper that inadequate sample sizes were used. The number of animals listed in that figure (during different parts of the experiments) are 12, 12, 12, 5, and 6, for an average of 9.4. That is not anything like what would be needed for a moderately convincing result, which would be a minimum of 15 or 20 animals for each study group, and probably more. The experiment relied crucially on judgments of fear produced by manual assessments of freezing behavior, which were not corroborated by any other technique such as heart-rate measurement. All mouse research papers relying on "freezing behavior" judgments are junk-science papers, for reasons I discuss in my post here, "All Papers Relying on Rodent 'Freezing Behavior' Estimations Are Junk Science."  The 2012 study does not describe in detail any effective blinding protocol, which is another bad defect.  The study involved stimulating certain cells in the brains of mice, with something called optogenetic stimulation. The authors have assumed that when mice freeze after stimulation, that this is a sign that they are recalling some fear memory stored in the part of the brain being stimulated. What the authors neglect to tell us is that stimulation of quite a few regions of a rodent brain will produce freezing behavior. So there is actually no reason for assuming that a fear memory was being recalled when the stimulation occurs. 

There does not exist any observational or experimental support for the existence of engrams (memory storage places) in any animal. Some papers have claimed to have produced such evidence, but their claims do not stand up to critical scrutiny. Papers claiming to produce such evidence are generally guilty of multiple types of Questionable Research Practices such as way-too-small study group sizes, lack of a blinding protocol, and the use of one or more unreliable techniques for judging memory performance. 

The LiveScience article then gives us this bit of excuse-making for why no one has ever read a memory from a brain: "The retrieval of a dead person’s memories is further complicated because the discrete parts of a memory are dispersed throughout the brain; for instance sensory details that can also be stored in the parietal lobe and sensory cortex." This is an appeal to the theory that a single memory is stored not in one tiny part of the brain but in multiple scattered parts of the brain. There is no evidence for such a theory, and the theory makes things worse for the person claiming that the brain stores memories, for reasons I discuss in my post "Why the 'A Memory Is Stored Throughout the Brain' Idea Makes Things Much Worse."  If a single memory were to be stored in multiple locations in the brain, then finding all of those locations and assembling them instantly (in a brain without any addresses or indexes or sorting) would be something even more impossible to explain than imagining that the memory existed in a single spot that was instantly found. 

Giving us its second example of claiming a cited source said something that it did not actually say, the LiveScience article states, "Neurons within a given engram are connected through synapses, the spaces between neurons where electrochemical signals travel, according to the National Library of Medicine."  The page that it links to does not ever use the word "engram," and does not refer to either memory or learning. The LiveScience article claims that according to the neuroscientist Arnold, "there is evidence that memories move to different locations as they are consolidated in the brain." There is no robust evidence of any such thing. Neuroscientists have no credible evidence of memories being stored in any part of the brain of any organism, and they do not have any decent evidence of a memory moving around from one part of the brain to another. 

Arnold is quoted as saying, "You get this sort of cascade of neurons that encode these different things, and each one of them is connected in this engram." That is hand-waving. Scientists lack any robust evidence of any such thing as an engram or an encoding of learned information or experiences in the brain. No scientist has a credible detailed theory of how such encoding could occur.  An ocean of difficulties arises when you start to consider the endless problems that would arise when trying to translate human learned knowledge and experiences into brain states through any imaginable system of encoding. Part of the problem is the extreme variety of things that people can learn and experience (concepts, facts, theories, visual  experiences, auditory experiences, smell experiences, taste experiences, pain experiences, touch experiences, and emotional reactions), meaning there could be no simple encoding scheme (something as simple as the genetic code) that could handle even a tenth of all the types of memories people can form. 

We have no discussion of some of the chief facts relevant to the topic discussed. Some of these facts are below:

(1) Human brain tissue has already been exhaustively studied at very high microscopic resolutions. My post "They Stored and Studied Thousands of Brains, But Still Failed to Show Brains Store Memories" discusses how places such as the Lieber Institute have microscopically studied thousands of brains, most of which were preserved very soon after death. The same post describes how Denmark's University of Odense has stored more than 9000 brains, microscopically examining a large fraction of them. Very much healthy brain tissue just-extracted from living patients has been microscopically examined, because normal brain tissue is often extracted from epilepsy patients when operations are done to prevent intractable seizures resistant to medicine. 

(2) Despite all of that microscopic examination, no one has ever found the slightest trace of any learned information by microscopically examining a brain. Microscopic examination of brain tissue has never revealed a single letter or character of anything anyone learned, and has never revealed a single pixel of anything anyone ever saw. It isn't just that no one ever found anything like "The US has 50 states" by microscopically examining brain tissue; it's that no ever found a U or an S from microscopically examining brain tissue. 

(3) The discovery of a bit of learned information from microscopically examining brain tissue is something that would be many times easier to do than the "recreation of a full memory" imagined by the LiveScience article, but neither of these things has occurred. 

(4) Modern microscopic techniques are powerful enough to discover traces of learned information in the brain if they existed, but no such discovery has occurred. 

(5) Nothing in the brain looks like any type of mechanism for storing learned information or storing memories.  Nothing in the brain looks like any type of apparatus for writing learned  information. 

(6) Nothing in the brain looks like any type of mechanism for reading a stored memory. We can imagine how some organism's brain might physically look like something capable of reading information from a particular spot, by means of something like a moving cursor or moving reading component. The brain has no such thing, and the brain has no moving anatomical parts. 

(7) The places claimed to be sites of brain memory storage (synapses) are unstable places of high molecular turnover, where all the proteins last for only a few weeks or less. There is no credible theory of how places so unstable could be storage places for memories that can reliably last for 60 years. 

(8) There is nothing in the brain that looks like learned information stored according to some systematic format that humans understand or do not understand. Even when scientists cannot figure out a code used to store information, they often can detect hallmarks of encoded information. For example, long before Europeans were able to decipher how hieroglyphics worked, they were able to see a repetition of symbolic tokens that persuaded them that some type of coding system was being used. Nothing like that can be seen in the brain. We see zero signs that synapses or dendritic spines are any such things as encoded information. 

(9) Many humans can remember with perfect accuracy very long bodies of text, but synapses in the brain do not reliably transmit information. An individual chemical synapse transmits an action potential with a reliability of only 50% or less, as little as 10%. A recall of long bodies of text would require a traversal of very many chemical synapses. A scientific paper says, "In the cortex, individual synapses seem to be extremely unreliable: the probability of transmitter release in response to a single action potential can be as low as 0.1 or lower."

Below is a diagram from the paper "Materials Advances Through Aberration-Corrected Electron Microscopy." We see that since the time the genetic code was discovered about 1953, microscopes have grown very many times more powerful. The A on the left stands for an angstrom, a tenth of a nanometer (that is, a ten-billionth of a meter). 

Currently the most powerful microscopes can see things about 1 angstrom in width, which is a tenth of a nanometer. How does this compare to the sizes of the smallest units in brains? Those sizes are below:

Width of a neuron body (soma): about 100 microns (micrometers), which is about 1,000,000 angstroms.

Width of a synapse: about 500 nanometers, about 5000 angstroms.  When you search for "width of a synapse," you will commonly get a figure of 20 to 40 nanometers, but that is the width of the synaptic cleft, the gap between two synapses or between a synapse and a dendrite. The full head is much wider, as you can see from the page here.

Width of a dendritic spine: about 50 to 500 nanometers, about 500 to 5000 angstroms.

Length of a dendritic spine: the site here says, "the thin spine neck, which connects the spine to the main dendritic branch, has lengths between 0.04 and 1 μm [microns] and has 'door knob'-shaped head structures with diameters that between 0.5 and 2 μm [microns]." That length dimension is between 400 and 10,000 angstroms; and that head diameter is between 500 and 20,000 angstroms. 

The visual below (from the page here) shows an electron microscope image of a synapse. The width of the synaptic head is more than 500 nanometers (nm). We see nothing that looks like any kind of storage of human learned information. The neurotransmitters inside the spherical vesicles are short-lived chemicals that don't even last a week. 

Below we see a closeup electron microscope photograph of some dendritic spines which are 500 nanometers (5000 angstrom) wide, from the scientific paper here "Ultrastructural comparison of dendritic spine morphology preserved with cryo and chemical fixation," by Tamada et. al.  We see nothing that looks anything like stored learned information or stored memory information. Do a Google search for "diagram of dendritic spine head" and you will get diagrams that look like nothing that could be any system for storing information long-term. The diagrams will show that such dendritic spine heads are just bags of short-lived  proteins and chemicals. A few of these diagrams may show actin filaments looking a bit like a structure, but searching for "lifetime of actin filaments" you will be told that such filaments have lifetimes of only minutes. 

The only thing in the brain smaller than the structures shown above are protein molecules. But we know a reason why protein molecules cannot be a storage place for memories that can last for 50 years. The reason is that the average lifetime of a brain protein molecule is 1000 times shorter than the longest length that people can remember things.  Proteins in the brain have an average lifetime of two weeks or shorter. 

A scientific paper states this:

"Experience-dependent behavioral memories can last a lifetime, whereas even a long-lived protein or mRNA molecule has a half-life of around 24 hrs. Thus, the constituent molecules that subserve the maintenance of a memory will have completely turned over, i.e. have been broken down and resynthesized, over the course of about 1 week."

Research on the lifetime of synapse proteins is found in the June 2018 paper “Local and global influences on protein turnover in neurons and glia.” The paper starts out by noting that one earlier 2010 study found that the average half-life of brain proteins was about 9 days, and that a 2013 study found that the average half-life of brain proteins was about 5 days. The study then notes in Figure 3 that the average half-life of a synapse protein is only about 5 days, and that all of the main types of brain proteins (such as nucleus, mitochondrion, etc.) have half-lives of 15 days or less.  The 2018 study here precisely measured the lifetimes of more than 3000 brain proteins from all over the brain, and found not a single one with a lifetime of more than 75 days (figure 2 shows the average protein lifetime was only 11 days). 

The paper here states, "Experiments indicate in absence of activity average life times ranging from minutes for immature synapses to two months for mature ones with large weights."

Clearly the resolution of the most powerful microscopes is powerful enough to read memories stored in neurons or synapses or dendritic spines, if such memories existed. And more than 10,000 brains have been microscopically studied in recent years. The failure to microscopically read any  memories from human brain tissue is a major reason for thinking that brains do not store human memories. 

If memories were stored in the brain, roughly about the year 1960 humans would have been able to read learned information stored in brains, when the resolution of microscopes reached about 10 angstroms. If memories were stored in the brain, we would have discovered irrefutable evidence of such a thing about 60 years ago. The total failure to find a single speck of learned information in the brain by microscopic examination is one of the strongest reasons for disbelieving in a brain storage of memories. 

I predict with great confidence that microscopes will never find the slightest trace of learned information in the human brain, because memories are not stored in brains. But we may have in the future some occasional "false alarm" claims to have accomplished such a thing, claims that are not supported by robust evidence. Neuroscientists have often been guilty of both smoke-and-mirrors trickery and pareidolia, when someone claims to see something that isn't really there, typically because he is eagerly scanning large bodies of random, ambiguous data, eagerly hoping to find something that isn't really there. So we may see some pareidolia in which a neuroscientist claims to see a memory by microscopic examination. Such a thing will be like some fervent believer in animal ghosts in the clouds examining thousands of photos of clouds, and claiming that this one or that looks like the shape of an animal. 

DNA has merely low-level chemical information

Note that in the LiveScience article there is not any mention of any scientist sounding hopeful about a possibility of discovering stored information in the brain. 

This week I was reminded of the ability of the human mind to retain memories for 50 years, contrary to what we would expect from the high molecular turnover in brains.  I had a recollection which proved the ability of the mind to recall very old memories that have not been recalled in half a century. For some reason I recalled a book I had read about 50 years ago, and never since: the science fiction book "Galaxies Like Grains of Sand" by Brian Aldiss. I remembered some lines from the book. I wrote them down on paper like this:

"The mirror of the past lies shattered. The fragments you hold in your hand."

After I wrote this recollection of something I had not read, thought of or heard quoted in fifty years, I borrowed the book on www.archive.org.  I see that the lines were these (almost exactly as I remembered them)

"The long mirror of the past is shattered...Only a few fragments are left, and these you hold in your hand." 

For a person like me, the mirror of the past is not shattered, but remains well preserved after 60 years, contrary to what we would expect if memories were stored in brains with such high molecular turnover and such constant remodeling of synapses and dendritic spines. 

Below is a quote on the same topic from an earlier post discussing why brains cannot be the storage place of very old memories:

"I know for a fact that memories can persist for 50 years, without rehearsal. Recently I was trying to recall all kinds of details from my childhood, and recalled the names of persons I hadn't thought about for decades, as well as a Christmas incident I hadn't thought of for 50 years (I confirmed my recollection by asking my older brother about it). ...Upon looking through a list of old children shows from the 1960's, I saw the title “Lippy the Lion and Hardy Har Har,” which ran from 1962 to 1963 (and was not syndicated in repeats, to the best of my knowledge). I then immediately sung part of the melody of the very catchy theme song, which I hadn't heard in 53 years. I then looked up a clip on a youtube.com, and verified that my recall was exactly correct. I also recently recalled 'The Patty Duke Show' from the 1960's, a show I haven't seen in 50 years, and recalled that in the opening title sequence we saw Patty walking down some stairs. I looked up the title sequence on www.youtube.com, and verified that my 50-year-old memory was correct. This proves that a 53-year-old memory can be instantly recalled."

The prediction I make here is just one of several predictions in my 2019 post "Contrarian Predictions Regarding Biology, the Brain and Technology."  So far my predictions in that post are holding up very well.