" We do not yet have a systematic theory of how information is encoded in the chemical and electrical activity of neurons, how it is fused to determine behavior on short time scales, and how it is used to adapt, refine, and learn behaviors on longer time scales. " -- "BRAIN 2025: A Scientific Vision," document co-authored by many scientists (link).
If we are to believe in the claim that brains store human memories, we must have a credible account of four things: encoding, neural storage of very old memories, the instantaneous formation of memories, and the instantaneous retrieval of memories. The theory that human memories are stored in the brain fails in regard to each of these things.
There exists no plausible theory as to how a brain could store memories lasting for 50 years, but we know humans can remember many things for that long. The most popular idea of brain memory storage claims that memories are stored in synapses, but the proteins in synapses have an average lifetime of less than two weeks, meaning such a theory falls short by a factor of 1000 when it comes to explaining memories that persist for 50 years. As for memory retrieval, there is no theory explaining how humans could possibly recall instantly things they learned many years ago, and haven't thought about in years.
You may hear the name of some obscure historical or cultural figure you learned about decades ago, and haven't heard about or thought about since that time. You may then instantly recall something about that person. But if that memory was stored somewhere in your brain, how could you instantly find the exact little location where that memory was? Doing that (for example, instantly finding a memory in storage spot 834,220 out of 1,200,000) would be like instantly finding a needle in a mountain-sized haystack. If a brain had an indexing system, or a coordinate system, or a neuron numbering system, there might be a faint hope for explaining instantaneous memory retrieval; but the brain has no such things. As for the instantaneous formation of memories, there is no theory that can account for it in a brain. The prevailing theory that memories are stored by synapse strengthening (which would involve protein synthesis requiring minutes) fails to account for memories that humans can form instantly.
When we consider the issue of memory encoding, we find a difficulty as great as the difficulties just discussed. Encoding is supposedly some translation that occurs so that a memory can be physically stored in a brain, so that it might last for years. The problem is that human memories include incredibly diverse types of things, and we have no idea how most of these things could be stored as neural states. Consider only a few of the types of things that can be stored in a human memory:
Memories of daily experiences, such as what you were doing on some day
Facts you learned in school, such as the fact that Lincoln was shot at Ford's Theater
Sequences of numbers such as your social security number
Sequences of words, such as the dialog an actor has to recite in a play
Sequences of musical notes, such as the notes an opera singer has to sing
Abstract concepts that you have learned
Memories of particular non-visual sensations such as sounds, food tastes, smells, pain, and physical pleasure
Memories of how to do physical things, such as how to ride a bicycle
Memories of how you felt at emotional moments of your life
Rules and principles, such as “look both ways before crossing the street”
Memories of visual information, such as what a particular person's face looks like
How could all of these very different types of information ever be translated into neural states so that a brain could store them?
Our neuroscientists have told us again and again that the brain does such an encoding, but there is no real evidence that any such thing takes place. What we have evidence for is merely evidence that humans remember things. If you are someone who believes that memories are physically stored in brains, then you may claim that memory encoding occurred at such and such a rate whenever you observe people learning something at such and such a rate. But merely observing evidence of learning or memory is not acquiring any actual evidence that encoding has occurred. There remains the possibility that our memories are not stored as neural states, the possibility that our repository of memory is some spiritual or psychic facility that is non-neural and non-biological.
Such a possibility should not seem remote when we consider that there is no workable theory as to how learned knowledge and experiences could be encoded so that they might be stored in a brain. No matter what theory we may create to account for the encoding of learned knowledge and episodic experience so that they can be stored in a brain, such a theory will always end up sounding ridiculous after we examine the theory in detail and consider its requirements and shortcomings. Let's look at some possibilities, and why they fail.
Theory #1: Direct writing of words and images
First, let's consider the simplest theory of encoding we can imagine – that a memory is stored in the brain so that it appears in a neural form pretty much as we see it in our minds. Under this theory, when you memorized some series of words, this would cause a sequence of microscopic little letters to become stored in your brain; and when you experienced some visual experience, this would get stored as some tiny little image in your brain. So, for example, under this theory, if someone memorized the sentence, “There may be green aliens in the center of the galaxy,” then after the person died, some scientist might examine that person's brain with an electron microscope, and actually find some tiny little words in some neurons, words that directly spelled out, “There may be green aliens in the center of the galaxy.” And under this theory, if someone was given a picture of a toy purple pony, and asked to memorize it, then after the person died, a scientist might be able to examine the person's brain under an electron microscope, and the scientist might say, “Aha, I see in his neurons a tiny little image of a toy purple pony.”
This theory may immediately provoke giggles, and it is rather easy to think of some reasons why it does not work. They are these:
If memory worked in such a way, we would surely have already discovered such easily-recognizable memory traces. But no such things have been seen, even though a great deal of human neural tissue has been examined at very high magnification. When we look at brain tissue at the highest magnification, we see no tiny little letters or tiny little images of animals, cars, and persons.
For a brain to be able to write words that we memorized in this type of direct manner, it would seem that the brain would need some very precise write mechanism, capable of forming the exact characters of the alphabet in brain tissue; but no such brain capability is known to exist.
It seems that if such a theory were true, recalling some words would be like reading. But recalling words is almost never like reading, and we don't see in our mind's eye some stream of letters as we recall some words we memorized.
For a brain to be able to read words that we memorized in this type of direct manner, it would seem that the brain would need some very precise reading mechanism, capable of reading the exact characters of the alphabet stored in very tiny letters written in brain tissue; but no such thing is known to exist. We don't have tiny little “micro-eyes” in our brains that might allow us to read tiny microscopic letters stored in our brains.
Alphabets of modern languages are relatively recent inventions. For example, the English alphabet is not many thousands of years old. There has no been no change in brain structure for many thousands of years, and we can think of no reason why brains would have some ability allowing it to write an alphabet that only came into existence centuries or a few thousand years ago, not many thousands of years ago.
Theory #2: Brain storage of words and images using some unknown non-binary coding or translation protocol
Now, let's consider a different theory of memory encoding – the idea that instead of directly storing words and images (so that we could directly read the words and directly see the images), the brain uses some type of unknown coding or translation protocols. For example, it could conceivably be that words that we learn are somehow translated into proteins or chemicals or electrical states, using some as-of-yet undiscovered translation scheme.
For example, such a scheme might work a little like this:
| Item | How the item might be represented |
| Letter “A” | Some particular neural arrangement of atoms, chemicals or electricity |
| Letter “B” | Some other neural arrangement of atoms, chemicals or electricity |
| Letter “C” | Some other neural arrangement of atoms, chemicals or electricity |
Such a scheme might work a little like the Morse code, in which particular letters are translated into some sequence of dots, dashes, or dots and dashes. Some particular arrangement of atoms, chemicals or electricity might work like a dot in the Morse code, and some other particular arrangement of atoms, chemicals or electricity might work like a dash in the Morse code.
Or there could be some higher-level translation system based on particular words rather than letters. For example, we can imagine something like this:
| Item | How the item might be represented |
| Word “sun” | Some particular neural arrangement of atoms, chemicals, proteins or electricity |
| Word “man” | Some other neural arrangement of atoms, chemicals, proteins or electricity |
| Word “move” | Some other neural arrangement of atoms, proteins chemicals or electricity |
There is one giant problem with such a theory. All of the languages that we use are fairly recent innovations, having been created in only the last few percent of the time that humans have existed. For example, back in the Roman Empire people used Latin, but the English we use today has only been in use for less than 1200 years. The alphabet used for English is less than 1000 years old, and its alphabetic predecessor (the Latin alphabet) is only a few thousand years old. It is generally acknowledged even by Darwinism enthusiasts that very complex evolutionary innovations cannot arise in only a few centuries of time or a few thousand years. So we could never explain how the brain could naturally possess some elaborate translation system based on such a relatively recent innovation as the English language and the English alphabet.
Scientists strain our credulity whenever they talk about novel functional genes accidentally appearing even over the course of a million years. Think, then, on how much greater a problem there would be in explaining how hundreds of novel functional genes could have appeared in less than 3000 years, to perform some translation operation involving characters and words that have existed for less than 3000 years. To assume such a thing would be to assume evolution working thousands of times faster than the rate we would predict from known mutation rates.
There is also no evidence that any such great burst of genetic novelty has occurred. Although the half-life of DNA is 512 years, we have enough samples of human DNA from ancient Rome and ancient Egypt to know that there has been no big change in the DNA of humans during the past 3000 years. So it seems impossible that there could be any genetic capability (arising in the past few thousand years) that would allow humans to neurally store information using some encoding mechanism specifically tailored to the letters and words of the English language that have existed for less than 3000 years.
Another difficulty with the theory of encoding just mentioned is that if it existed, we would see big differences in the genes of people who spoke different languages. According to such a theory, we would expect that Chinese people would have one group of genes corresponding to proteins or RNA molecules needed to translate Chinese words into neural states, and that English speaking people would have some other quite different set of genes corresponding to proteins or RNA molecules needed to translate English words into neural states (particularly since the Chinese language and alphabet is so different from the English language and alphabet). But there exists no such difference in the genes of Chinese speaking people and English speaking people.
There is also the difficulty that there is no sign in the human genome that any such genes exist for performing such an elaborate operation of encoding human learned knowledge and episodic experience so that it can be stored in neurons or synapses (and there would need to be many hundreds or thousands of types of genes dedicated to performing such a task if it was done).
Theory #3: Binary writing of words and images
Now, let's consider a theory of memory encoding that perhaps the words we memorize and the images we remember are stored in binary format. We know that computers store information in binary format, so when it is suggested that the brain may use a similar format, this may sound reasonable to the average person (although it isn't, a brain being radically different from an electronic computer).
This possibility actually has all of the difficulties of the previous possibility. What goes on when your computer stores words in binary format is the following:
First individual letters in the words are converted into decimal numbers (such as 13, 19, and 23) using a particular translation table called the ASCII code.
Then, those numbers are converted from decimal to binary using a decimal-to-binary conversion routine.
So if we are to believe that the brain does binary encoding like a computer, we would need to believe that built into the brain on a low level is some type of translation scheme like the one below, a scheme in which letters are translated into decimal numbers.
ASCII table used by a computer to store encoded information
In addition, we would also have to believe that the brain has some kind of capability to translate the numbers in such a system into binary numbers. Alternately, we could believe that the brain has a scheme for directly translating characters into binary, but the overall complexity of such a translation mechanism would be every bit as great as a system in which characters are converted into decimal, and then into binary.
We have the following difficulties involved with such an idea:
If memory worked in such a way, we would surely have already discovered such easily-recognizable memory traces. We would have discovered tiny little traces in the brain that resemble binary coding. But no such things have been seen, even though a great deal of neural tissue has been examined at very high magnification.
For a brain to be able to write words that were memorized in this type of direct manner, it would seem that the brain would need some very precise write mechanism, capable of writing binary traces; but no such thing is known to exist.
For a brain to be able to read words that we memorized in this type of direct manner, it would seem that the brain would need some very precise reading mechanism, capable of reading in binary; but no such thing is known to exist.
Since the alphabets of human languages are only a few thousand years old, there would have been no time for the human body to have evolved some complex biological mechanism capable of converting specific alphabetic characters to binary.
We can imagine no way in which a brain could achieve the translation effect in which words are translated into binary. As far as we know, there is nothing anything like an ASCII table in your brain, nor is there anything like a facility for translating English letters directly into binary, nor is there anything like a facility for translating English letters into decimal, and then translating decimal numbers into binary. There are no genes in the genome that perform such tasks.
The Scientists Who Keep Falsely Talking About Memory Encoding and Memory Representations in Brains
The simple fact is that there is not the slightest evidence of memory encoding or memory representation in the human brain. So why it that we keep getting scientific papers claiming to have seen memory encoding or memory representation in the human brain? It's pretty much a "they're talking like they had what they need to have but don't have" kind of affair. Something similar might be going on if some street beggar were to try to attract women by frequently using finance terms. So someone without $20 to his name might speak like this: "I think that WEALTH MANAGEMENT is very important, and I am slowly BUILDING MY FORTUNE in a way that will give me a HUGE BONANZA OF WEALTH once my INVESTMENT PLANS are actualized."
But how can someone write a paper making frequent references to memory encoding and memory representation in the brain, even though there is no evidence that such things exist? The visual below shows the general approach typically used.

A key element is what can be called chance-mining. Chance-mining typically involves grandly trumpeting some little result that might easily be obtained by pure chance. I can give an example of chance-mining. Suppose you are doing a study trying to prove what we may call "the Abracadabra Hypothesis," which you define as "the hypothesis that saying 'Abracadabra' before flipping a coin will increase the chance of a Heads result." Any test involving a sufficiently large sample size will fail to support this Abracadabra Hypothesis. That's because something called the Law of Large Numbers says that the more random trials you do, the more the result will tend to match the result expected by chance. But it is very easy to get a test result deviating from what is expected by chance, if you use a very small sample. For example, it is easy to flip ten coins and get 6 or 7 Heads results, even though the expected chance result is 5.
So if you want to do a paper claiming to support the Abracadabra Hypothesis, you can try a test using a small number of coin flips such as only 10 or 20. If that fails, you can file the results in your file drawer, and start a new experiment, also using a small number of coin flips. Probably before long you will have some result you can claim as "statistically significant." Chance-mining like this misleads people, because it creates the impression that there is a causal relation or causal influence when there is none. Saying "Abracadabra" actually has no influence on the result of coin flips.
Similar chance-mining occurs in quite a few neuroscience papers. The papers may make quite a few references to neural encoding or neural representation, but they will not be backed up by references to well-designed studies using an adequate sample size. Typically the paper will present some research that is utterly unreliable for multiple reasons, such as the use of way-too-small study group sizes or unreliable techniques for trying to measure recall in rodents.
A example of such a paper is the paper here, entitled "Ventral hippocampus neurons encode meal-related memory." The title is unjustified. No robust evidence has been provided of any neural encoding of memory. There are two gigantic flaws in the study:
(1) The study group size is way too small, consisting of only 5 animals.
(2) No reliable method was used to measure memory performance in rodents. We read that a "foraging-related spatial memory task" apparatus was constructed to test memory in mice. We see a picture of a weird device that the paper does not name. This was not any well-established protocol for testing memory in mice. We fail to have any diagram explaining why such a device would reliably test memory in mice.
What usually occurs in such papers claiming evidence of "memory encoding" or "memory representation" is that there will be a combination of two main sins, either one of which is to disqualify a paper as good evidence:
(1) Almost always there will be some study group size that is way too-small for any reliable evidence to be honestly claimed
(2) Usually there will be a reliance on a completely unreliable measurement for estimating fear or recall in rodents, the method of trying to judge "freezing behavior." All papers relying on this method are junk science, for reasons I discuss here.
What largely goes on in such poorly written science papers is pareidolia. Pareidolia is what occurs when someone keeps scanning some stream of random data, looking for something he can call a representation. An example is a person who eagerly scans his toast every day, looking for some sign of a representation, and who one day announces he has found the face of Jesus in his toast, or maybe the face of the Virgin Mary, or maybe the face of his dead wife.
The neuroscientist eagerly scanning brain scan data or brain wave data looking for something he can call a little bit of "representation" or "encoding" is someone who we can no more trust than someone eagerly scanning the clouds every day, looking for something that looks like the shape of an animal.
An example from 2025 of a pure pareidolia paper is the junk science paper "Movie-watching evokes ripple-like activity within events and at event boundaries." We have scientists looking at EEG readings obtained in ten epilepsy patients while the patients watched movies. Looking at the ever-changing line squiggles that are EEG readings, the authors claim to have seen "ripples" that they claim occur more often during "event boundaries." The claim that there are such "ripples" in the data is as much see-what-you-want-to-see pareidolia as the claim that there are particular points in movies that are "event boundaries." The supposed identification of these "ripples" occurred not by humans staring at the EEG readings, but by some computer program which is a black box of convoluted spaghetti code. Computer programming is the best friend of the scientist trying to see things that are not really there. You can run some computer program that is supposedly seeking some obscure thing in noisy data; and if the first analysis run fails, you can keep tweaking the code until it reports finding what you were hoping to find.