Monday, August 26, 2024

Look Very Closely at a Study Claiming Thought Reading of Brains, and You'll Find the Shady Tricks Behind It

Certain web sites tend to fall "hook, line and sinker" for very dubious and poorly designed neuroscience papers (something that are extremely abundant these days). A recent example is a Gizmodo.com story with the very untrue headline "Brain-Reading Device Deciphers Internal Thoughts With Surprising Precision." We have an article hyping a new science paper with the groundless title "Representation of internal speech by single neurons in human supramarginal gyrus."

The EEG is a device attached to a head, a device that reads brain waves. EEG devices that measure brain waves are strongly influenced by muscle movements, and speech is a type of muscle movement. It does nothing to show that brains produce thinking if you have some EEG device that can detect different responses when different things of different length are spoken. That can be mainly picking up muscle movements, not thought. EEG devices are very sensitive to muscle movements, and if you have a medical EEG reading you will be told not to move during the reading.  

To try to back up unfounded boasts of being able to detect thoughts from brain activity, neuroscientists sometimes claim that they are picking up signals during "internal speech." What is the difference between "internal speech" and actual speech? Actual speech is when you say a word, and "internal speech" is when you only think of the word.  Unless a study is carefully designed, what will happen is that faint amounts of actual speech may occur when subjects were supposed to be using only internal speech. No such careful design has occurred in this study. Instead, we wonder whether the authors had chosen a design trying to get lots of traces of actual speech that could be called internal speech. 

Here is how a carefully designed study might be done, in a way that would minimize the chance of subjects producing a slight amount of actual speech (such as silently mouthing a word) when they were supposed to be only producing internal speech:

(1) A subject might first see a screen saying: "Please speak aloud this word: automobile."

(2) After the response was recorded, a device would then be put in the subject's mouth, to prevent any muscle movement in his mouth. 

(3) The next screen might say: "Now we want you to do something very different: to only think a word we give you, without moving your muscles at all. Be very careful not to move any muscle."

(4) Then the next screen might say: "Now please ONLY THINK this word: locomotive."

Nothing like this was done. We read this description of how the subjects or subject was instructed to act:

"During the cue phase, a speaker emitted the sound of one of the eight words (for example, python). Word duration varied between 842 and 1,130 ms. Then, after a delay period (grey circle on screen; 0.5 s), the participant was instructed to internally say the cued word (orange circle on screen; 1.5 s). After a second delay (grey circle on screen; 0.5 s), the participant vocalized the word (green circle on screen, 1.5 s)."

Get the picture? It was a super-hurried affair.  The "ms" in the quote above refers to milliseconds or thousands of a second, and the "s" in the instructions above stand for a second. Within a five-second period, the people tested were supposed to first speak a word, then only think the word, and then again speak the word. What can we expect would happen given so very hurried a situation, in which people were supposed to switch so quickly between speaking a word and only thinking a word, with two vocalizations of a word and one thinking of the word all occurring within five seconds? There would be a high chance of failing to follow the instructions properly. Given such instructions, the reported results are no compelling evidence for any detection of internal speech.  

Here's a test I want you to try right now, one with three easy, safe steps I want you to perform real fast, in under ten seconds:

(1) First give a big smile and say the word "rabbit" loud and clear.

(2) Next, give a big smile and again say the word "rabbit" loud and clear.

(3) Next, give a big smile and think the word "rabbit."

My guess is that at least 30% of my readers trying this test spoke or mouthed the word rabbit" when they came to the third line, even though that line said to merely think that word. Whenever instructions are given very rapidly, and there's a sudden change in the instructions, there's a large chance the instructions will not be followed exactly. 

So we can assume that given the instructions quoted in italics above (in which instructions are given to first speak a word, then think a word, and then speak the word again, all within five seconds), that in a large fraction of the cases some actual speech or mouth muscle movement occurred during the second part when the subjects were supposed to be only thinking the word.  So probably very much of the recorded "internal speech" was something more, including muscle movement. 

How many subjects were used? Only one subject for one of the tests, and two subjects for some other tests.  Were many trials used? No, not very many. Each subject was asked to think a total of only about 100 words. 

The subjects were given one of eight words to speak and then think of: battlefield, cowboy, python, spoon, swimming, telephone, bindip and nifzig.  Using only a time factor based on the length of activity, and the time of task engagement, a computer program could could probably predict with 50% accuracy which word was used. 

The reported results (about 50% prediction accuracy for some computer program) are results that can easily be explained without assuming any pure thoughts in the brain, by assuming:

(1) a significant fraction of the words that are claimed as "internal speech" actually involved traces of actual speech such as softly spoken words or mouthed words, which occurred because of the very rushed time frame in which participants were supposed to speak a word, then think the word, then speak the word all within five seconds (with a sudden change from instructions to speak a word to instructions to think a word). 

(2) the difference in word lengths was leveraged to help predict which word was mouthed or thought of;

(3) simple chance was leveraged,  easy to do in a situation where scientists are free to file away failing results in their file drawers. 

Because of the shady tricks used, we have here no evidence at all of picking up thoughts from some region of the brain.  A properly designed study of this type would have characteristics such as these:

(1) Instead of instructions given so rapidly or such a rapid-pace timescale (as if they were designed to produce a large amount of failure to follow the instructions), the instructions would be delivered slowly with a longer timescale, to maximize the chance that when subjects were supposed to be thinking (and not speaking), they really would be only thinking. 

(2) Additional measures would be taken to prevent mouth muscle movement when the subjects were supposed to be only thinking, measures such as putting something in the subject's mouth to prevent muscle movement. 

(3) All of the test words would be of an identical length, to prevent some computer program from predicting based merely on the length of the subject activity. 

For more on the misleading tricks used by studies claiming thought reading of brains, see my three posts below:

No One Is Actually Doing Thought-Reading by Scanning Brains or Reading Brain Signals

Misleading Tricks of the Latest Claim of Mind-Reading by Brain Scans

Suspect Shenanigans When You Hear Claims of "Mind Reading" Technology

Claims of mind-reading by brain scans or brain signal reading will continue, and they will typically be based on tricks such as these:

(1) Picking up signs of muscle movement, always possible for anyone who can talk, and wrongly passing that off as detection of "inner thought," aided by study designs which maximize the chance of "contrary to the instructions" muscle movement (or allow a possibility of some kind of muscle movement) when only "inner thought" is supposed to be occurring.
(2) Having tests with words of very different lengths, with a claimed detection of which word was thought of, the success being mostly based on longer time intervals corresponding to such longer words, not any real detection of what someone was thinking. 
(3) Various sneaky tricks in which data backdoors are leveraged, so that predictive success (claimed to be from reading brain data) is mostly coming from data grabbed from a source other than brain data (such as the study that showed people images, and that leveraged previously gathered descriptive data that existed for each of the images presented).


scientist on pedestal

Monday, August 19, 2024

Exhibit A That There Is No Such Thing as a Chemical Root of Consciousness

Neuroscientists have failed miserably in trying to show or explain a neural basis for the human mind. But what about chemists? Their efforts to explain human mentality are just as fruitless as the efforts of neuroscientists. As Exhibit A to back up this claim, I refer you to a recent essay by emeritus chemistry professor Addy Pross, one entitled "The Chemical Roots of Consciousness." The essay by Pross fails completely to explain any such thing as a chemical basis for consciousness and mind. Pretty much all that Pross has to offer is a bag of fallacious tricks. Once you analyze which tricks were used, you may understand what a "there's no there there" situation we have, with nothing of any explanatory substance being offered, mainly just  rhetorical sleight of hand. 

Pross begins with a favorite trick of materialists when trying to explain minds. They have the big problem that there is nothing in the human brain or its chemistry that does anything to explain any of the main features or capabilities of the human mind.  So what can you do when you're trying to show the human brain causes the human mind, but there's nothing in a brain that does anything to explain the main characteristics and capabilities of minds? You can try to change the subject into a discussion of something else.  A great way to do that is to start talking about events that may have occurred eons ago.  The advantage of that is that no one can ever disprove what you are claiming. So you can pretty much tell any kind of tall tales you want. 

While taking this route, Pross states this:

"Evolution, as Darwin already sensed, is more about improving than inventing. Accordingly, the evolutionary process, from its outset, would have taken place along both physical and mental axes. The Chilean philosopher Humberto Maturana effectively made the same point with his comment some decades ago that ‘living as a process is a process of cognition’. Life’s mental aspect is as fundamental as its physical one. But if evolution started in chemistry, as argued above, it implies that the mental dimension would also have started in chemistry, say with minimal cognition"

No, according to the mainstream theory of evolution, life existed for billions of years before there was any cognition at all. Biologists do not maintain that evolution occurred along a "mental axis" from its beginning. They maintain that there was nothing like mind or consciousness for the first billions of years that life existed, on the grounds that during those billions of years there existed nothing but microbes.  Pross has told us a groundless, silly story of microbes with minds, a story lacking any credibility. 

Pross then proceeds to give us about four paragraphs discussing evolution, none of which has any relevance to explaining how there could be any such thing as a chemical basis for consciousness and minds. He then goes on to a ridiculous comparison, one comparing the bodies of organisms to water fountains. It's hard to think of a more ridiculous comparison. Human bodies are states of vast hierarchical organization. The water in water fountains has no organization at all.  Very absurdly, Pross says, "Dynamically speaking, you have more in common with that water fountain than you might have thought!" Nonsense. 

Pross tries to support this absurd claim by pointing out that the cells in human bodies are often replaced. It is true that structures in the human body such as cells and synapses are often replaced, with the turnover time varying very much from one type of structure to another. But such a reality does nothing to support any claim that the mind is the product of the brain. To the contrary, the claim that brains store memories is undermined and discredited by the reality of rapid protein turnover and the short lifetimes of synapses and dendritic spines. Someone in his seventies can remember very well the experiences he had and the things he learned sixty years ago, but that would not be possible if memories are stored in brains that have such rapid turnover of synapses, protein molecules and dendritic spines. 

Perhaps realizing that his essay is mostly finished, and that he has done nothing to explain minds or consciousness, Pross boasts that he will do that, saying this:

"So let me now address the question at the heart of this essay: how, and why, did mind emerge from matter? Why consciousness? The answer to the ‘why’ question is relatively simple: nature, the ultimate technologist, ‘discovered’ that mind is functionally useful. Mind enables cognitive processes such as thinking, decision-making and memory. A mindful entity has survival advantages over a mindless one. Simply put, mind enhances persistence."

This is vacuous as an explanation. Saying "because it was useful" does nothing to explain how some hard-to-explain reality could have occurred in some way that should not have been possible. If you're wandering in the cold woods, and suddenly see that 100 fallen logs assemble themselves into a log cabin that makes a good place for you to spend the night, you do not explain such a marvel by saying it occurred "because it was useful."

We then have some groundless boasting by Pross, combined with a false definition. He states this:

"The ‘how’ question is the challenging one. A breakthrough event here was the novel preparation a little over a decade ago of a chemical DKS system, based on one of the most common reactions in organic chemistry. Such dynamic chemical systems were effectively unknown prior to that discovery. Indeed, in short order, many such chemical DKS systems were subsequently prepared. But what was striking about these unfamiliar chemical systems was that they exhibited unexpected life-like characteristics, in particular, rudimentary cognition. Cognition, a biological term, is traditionally defined as ‘the mechanisms by which living things acquire, process, store, and act on information from the environment’. Well, chemical DKS systems begin to do just that – they process, store, and act on information from the environment!" 

The definition of "cognition" supplied is a false one. Here are some dictionary definitions of "cognition":

  • "the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses." -- "Oxford Languages" definition that comes up first in a Google search for "definition of cognition"
  • "cognitive mental processes" -- Merriam Webster dictionary
  • "the use of conscious mental processes" -- Oxford Dictionary
  • "the act or process of knowing; perception" -- Dictionary.com
  • "the mental process involved in knowing, learning, and understanding things" -- Collins Dictionary

None of these definitions match the definition that Pross has given for cognition: "the mechanisms by which living things acquire, process, store, and act on information from the environment."  That is not a  correct definition of cognition. The use of give-you-the-wrong-ideas language by Pross continues, as he states this, talking about some mere chemical reaction:

"But the DKS system’s existential dependence on its environment has a surprising and unexpected consequence. It initiates a sense of ‘self’ for that system – there is ‘me’ and there’s the outside world on which ‘me’ depends." 

This is baloney. Some mere chemical reaction would not have any kind of cognition, would not have any kind of sense of self, and would not have any sense of "me." The use of words in quotation marks in the quote above should alert you that you are being told something unbelievable. Similarly if someone says "the price for my 'car' is $2000," the use of the word "car" in quotation marks should alert you that you are being bamboozled. A search for the term "DKS system" on Google Scholar seems to indicate that no one is using such a term other than Pross and his co-authors. 

There's nothing more of any substance in the article by Pross. Nothing has been done by him to show any chemical root of consciousness, nor has he done anything to show any relation between chemistry and mentality.  His article has little more than tricks, digressions, groundless boasts, a false definition and untrue claims. 

In general, chemists have very low credibility when they speak on grand questions of origins. We must rate them as having very low credibility about such topics because of the long history of chemists misleading us about origin-of-life research, claiming that they were making progress when no real progress was being made. Such misleading language occurred very massively between 1950 and 2024. 

====================================

How to Make It Sound Like You Understand Some

Great Origin Mystery Vastly Beyond Your Understanding, 

a Mystery a Thousand Miles Over Your Head

====================================

(1) Refer to the mystery using super-diminutive language,

which makes it sound a billion times simpler than it is.

(2) Refer to some obscure reality or speculation that almost no one understands very well.

(3) Claim that so obscure a reality or speculation "sheds light" or "helps clarify" or "helps demystify" the huge mystery you don't understand, and that you are therefore "beginning to understand" the mystery. 

Example #1: 

(1) Refer to the Big Bang origin of the universe, describing it using super-diminutive language as "just some density reduction," making it sound a billion times simpler.

(2) Mention the very obscure speculation of "cosmic inflation," a theory existing in hundreds of forms, a theory which almost no one understands very well.

(3) Claim that this "cosmic inflation" speculation "sheds light" on the origin of the universe, or "helps demystify" it or "helps clarify" it, and that you are therefore "beginning to understand" the mystery.

Example #2: 

(1) Refer to the problem of how human minds and memory and human mental experiences and human mental capabilities arise, referring to this in super-diminutive language as a mere "problem of consciousness," which makes the problem sound a billion times simpler.

(2) Refer to some obscure little-understood physical reality such as "quantum entanglement" or maybe some little-understood chemistry speculation. 

(3) Claim that whatever little-understood physical reality you have chosen "sheds light" on the origin of minds or "helps demystify" or "helps clarify" such origins. 

Below is someone who might use such shady explanatory tactics:

scientist to-do list

Monday, August 12, 2024

A Report of "Unimpaired Faculties Without a Brain" (John Bly)

 An invaluable resource to the serious scholar of the human mind is the web site www.iapsop.com, which allows you to freely and conveniently examine many important sources of information about the human mind and human psychical experiences, much of it information that is hard to find elsewhere. Among the resources are very many editions of the Journal and Proceedings of the Society for Psychical Research. At such a site I am now enjoying reading editions of the publication The Metaphysical Magazine. On page 71 of Volume 5, the January-May 1897 volume, we have the astonishing report below:

BRAINS UNNECESSARY. 

"Dr. S. S. Koser, of Williamsport, Pa., has made a wonderful discovery, which will be a theme for discussion among medical men throughout the country. His knife has revealed a medical wonder, in which a man had unimpaired faculties without a brain

At the request of a number of prominent physicians of Philadelphia, Dr. Koser held a post-mortem examination of the remains of John Bly, of Watsontown. Bly, who was twenty years of age, for a long time suffered with a tumor, which grew into the very base of the brain, and occasioned his death. The growth had a visible effect upon his brain, and the case became a curiosity to the medical profession. The tumor was imbedded too deeply into the brain tissue to admit of an operation. It was found that the tumor was nearly as large as a billiard ball. It was so located as to demoralize the nerves of the sight centre, and as a consequence young Bly was blind for over three years. The most singular fact developed was that the entire brain had been hollowed out by the action of the tumor. The cavity was at least five inches in length, and was filled with pus. All that was left of the brain was a thin shell, composed of the tougher tissues where the brain matter gathers into nerves, which were less susceptible to the process of decay. When an incision was made in the shell the whole mass collapsed. 

The circumstances which made the case almost unprecedented in the annals of medical science was the manner in which the patient retained his rationality and faculties under the circumstances. He had the senses of touch, taste, hearing, and smell, had very tolerable control of his locomotor muscles, could talk, and, in fact, was comparatively discommoded in no other way than by the loss of vision. His retention of memory was remarkable. He was able to memorize poems up to within two weeks of his death.—Philadelphia Ledger."

The report (repeated here with the same details) should come as no great surprise to those familiar with other similar reports provided by the physician John Lorber. As discussed in this paper, Lorber studied many patients with hydrocephalus, in which healthy brain tissue is gradually replaced by a watery fluid. A mathematics student with an IQ of 130 and a verbal IQ of 140 was found to have “virtually no brain.” His vision was apparently perfect except for a refraction error, even though he had no visual cortex (the part of the brain involved in sight perception).

The paper says that of about 16 patients Lorber classified as having extreme hydrocephalus (with 90% of the area inside the cranium replaced with spinal fluid), half of them had an IQ of 100 or more. The article mentions 16 patients, but the number with extreme hydrocephalus was actually 60, as this article states, using information from this original source that mentions about 10 percent of a group of 600. So the actual number of these people with tiny brains and above-average intelligence was about 30. The article states:

"[Lorber] described a woman with an extreme degree of hydrocephalus showing  'virtually no cerebral mantle' who had an IQ of 118, a girl aged 5 who had an IQ of 123 despite extreme hydrocephalus, a 7-year-old boy with gross hydrocephalus and an IQ of 128, another young adult with gross hydrocephalus and a verbal IQ of 144, and a nurse and an English teacher who both led normal lives despite gross hydrocephalus."

Then there is a case in which a human managed to function well in society as a French civil servant, even though he had almost no functional brain. The case is discussed here in a story entitled “Man lives normal life with abnormal brain”:

Inside a normal brain are tiny structures called lateral ventricles that hold brain fluid. In this man's case, the ventricles had swollen up like balloons, until they filled almost all of the man's brain. When the 44-year-old man was a child, doctor's had noticed the swelling, and had tried to treat it. Apparently the swelling had progressed since childhood. The man was left with what the Reuters story calls “little more than a sheet of actual brain tissue.”

But this same man, with almost no functioning brain, had been working as a French civil servant, and had his IQ tested to be 75, higher than that of a mentally retarded person. The Reuters story says: “A man with an unusually tiny brain managed to live an entirely normal life despite his condition, caused by a fluid buildup in his skull.” The case was written up in the British medical journal The Lancet in a paper entitled “Brain of a white-collar worker.” It was as if the authors had chosen a title which would cause as few people as possible to read the paper, because people reading the paper would stop believing the "brains make minds" dogma of neuroscientists. 

Monday, August 5, 2024

Papers Claiming Brain Memory Storage Keep Citing Poor Science Papers

Let us look at all the flaws, internal contradictions and incorrect statements in a 2022 paper purporting to provide evidence of engrams (cells or matter in the brain which are claimed to store memories).  The paper is entitled "The essence of the engram: Cellular or synaptic?" The second sentence of the paper makes this very untrue claim: "In the last few years it has been shown that simple association memories can be encoded by a subset of the neuronal population called engram cells." This is an example of what I call an achievement legend, which is when scientists boast of having achieved something that was not actually achieved. A careful and sufficiently critical examination of all papers claiming to provide evidence for engrams will show that none of them was good experimental science. Research claiming to provide evidence for engrams is plagued by Questionable Research Practices, and fails to be robust scientific evidence.  

Early on the paper makes this unfounded claim: "Over the last few decades, numerous discoveries have been made regarding the properties of memory ranging from identification of the molecular mechanism(s) underlying memory formation to establishing the different temporal phases of memory." Scientists are actually completely lacking in any understanding of any molecular mechanisms underlying memory formation.  There is no scientist who can even give a credible explanation of how something as simple as the phrase "my dog has fleas" could be stored in a brain.  Contradicting the previously quoted statement, the paper says a bit later,   "the physical basis of memory is elusive."  

We then read this untrue statement: "There is now a substantial body of evidence based on recently developed techniques, including optogeneticschemogeneticselectrophysiology, and multiphoton confocal imaging, to suggest that memory for basic types of behavioral learning such as contextual fear conditioning is maintained in a population of neurons referred to as engram cells [4][5][6][7][8]." Notice the hedging in the language. People often use the term "substantial" when they don't have much of anything. If your mother asks you, "Have you finished your term paper?" you might say, "I've done substantial work" when you haven't done much of anything.  The use of the word "suggest" indicates uncertainty. An examination of the studies referred to shows that none of them establish any robust evidence for any such things as engram cells. 

Let's look at exactly the studies referred to above. Before discussing this, let me list some of the types of study defects I previously listed in my post "The Seven Sins of 'Memory Engram'  Experiments."  The sins I mentioned were as follow:

  • Sin #1: assuming or acting as if a memory is stored in some exact speck-sized spot of a brain without any adequate basis for such a “shot in the dark” assumption.
  • Sin #2: Either a lack of a blinding protocol, or no detailed discussion of how an effective technique for blinding was achieved.
  • Sin #3: inadequate sample sizes, and a failure to do a sample size calculation to determine how large a sample size to test with.
  • Sin #4: a high occurrence of low statistical significance near the minimum of .05, along with a frequent hiding of such unimpressive results, burying them outside of the main text of a paper rather than placing them in the abstract of the paper.
  • Sin #5: using presumptuous or loaded language in the paper, such as referring in the paper to the non-movement of an animal as “freezing” and referring to some supposedly "preferentially activated" cell as an "engram cell." 
  • Sin #6: failing to mention or test alternate explanations for the non-movement of an animal (called “freezing”), explanations that have nothing to do with memory recall.
  • Sin #7: a dependency on arbitrarily analyzed brain scans or an uncorroborated judgment of "freezing behavior" which is not a reliable way of measuring fear.

Here are the papers referenced:

  • Reference 4 in the "Essence of the Engram" paper refers to the paper “Optogenetic stimulation of a hippocampal engram activates fear memory recall.” 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 per study group. So the study is  guilty of Sin #3. The study is also guilty of Sin #7. 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. The study does not describe in detail any effective blinding protocol, so it is also guilty of Sin #2. The study is also guilty of Sin #6. 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 is being recalled when the stimulation occurs. 
  • Reference 5 in the "Essence of the Engram" paper is a reference to the 2013 study "Creating a false memory in the hippocampus." When we look at Figure 2 and Figure 3 of that  paper, we see that the sample sizes used were paltry: the different groups of mice had only about 8 or 9 mice per group. Such a paltry sample size does not result in any decent statistical power, and the results cannot be trusted, since they very easily could be false alarms. A sample size calculation would have revealed the defect, but the authors failed to do such a calculation.  No convincing evidence has been provided of creating a false memory. The paper also judged fear in rodents by subjective judgments of "freezing behavior," which is not a reliable way to measure fear in rodents. A reliable way to measure fear in rodent is to measure heart rate, which consistently spikes very sharply when rodents are afraid.  The study also failed to use any blinding protocol. 
  • Reference 6 in the "Essence of the Engram" paper is a reference to the study "Bidirectional switch of the valence associated with a hippocampal contextual memory engram."  We see in that paper 5 or 6 results reported with a borderline statistical significance of only "< 0.05," so this paper is  guilty of Sin #4. No detailed description is given of how an effective blinding protocol was achieved, and only the skimpiest mention is made of blinding, so this paper is guilty of Sin #2.  The study used only "freezing behavior" to try to measure fear, without corroborating such a thing by measuring heart rates.  So the paper was guilty of Sin #7.  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 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 is being recalled when the stimulation occurs.  So the study is also guilty of Sin #6. 
  • Reference 7 in the "Essence of the Engram" paper is to a  paper by Ramirez and Liu  published in Nature, one entitled, “Activating positive memory engrams suppresses depression-like behaviour.” Figure 2 of the paper says that in one group there were only 6 mice used, and elsewhere the paper states that a control group had only 3 mice. These sizes are way below the 15 or 20 animals per study group (control and non-control) recommended as a minimum for a reliable experimental result. The authors claim to have counted differences in the degree to which mice “struggled” when presented with a maze – again something involving a subjective interpretation in which a researcher might tend to see whatever he wants to see. The authors' interpretation of what is going on is speculative. The authors do not present any solid evidence that they actually activated a memory by optogenetic stimulation.
  • Reference 8 in the "Essence of the Engram" paper is to the paper "Memory engrams: Recalling the past and imagining the future." The paper is not a paper that presents original research, but one that simply cites previous research, such as the bad studies mentioned above.  The paper is co-authored by Susumu Tonegawa, who co-authored several of the poorly designed and unreliable studies mentioned above. 

So let's summarize what has gone on in this crucial part of the "Essence of the Engram" paper. The authors have made the claim that there is a "substantial body of evidence" for engrams, and have cited five different papers as references. Not one of those papers presents any robust original research supporting claims that engrams exist. The first four papers cited are low-quality science studies that failed in numerous ways to be good experimental science. The fifth paper is co-authored by the co-author of several of these low-quality science studies, and presents no new research.  This is what goes on all the time in literature referring to engrams.  You have either papers presenting low-quality science experiments, or you have papers that refer to low-quality science experiments.  Nowhere will you find any solid research presenting any robust evidence for engrams.  

 Later in the "Essence of the Engram" paper we read this untrue claim: "Han et al. [14] provided the first causal evidence that engram cells are qualitatively different from non-engram cells."  The reference is to the low-quality science paper "Selective Erasure of a Fear Memory." In Figure 1 of that paper we see a larger-than average sample size was used for two groups (17 and 24), but that a way-too-small sample size of only 4 was used for the corresponding control group. You need a sufficiently high number of animals in all study groups, including the control group, for a reliable result.  The same figure tells us that in another experiment the number of animals in the study group were only 5 or 6, which is way too small. Figure 3 tells us that in other experiments only 8 or 9 mice were used, and Figure 4 tells us that in other experiments only 5 or 6 mice were used. So this paper is guilty of Sin #3. No mention is made in the paper of any blinding protocol, so this paper is guilty of Sin #2. Figure 4 refers to two results with a borderline statistical significance of only "< 0.05," so this paper is also guilty of Sin #4.  The paper relies heavily on judgments of fear in rodents, but these were uncorroborated judgments based on "freezing behavior," without any measure of heart rate to corroborate such judgments. So the paper is also guilty of Sin #7. 

I could go on and on here, but you can get the idea. What goes on in these kind of review papers are endless references to defective, poorly designed research. 

Contrary to the previous claims I quoted from the paper "The essence of the engram: Cellular or synaptic?" is the paper's statement that "the physical form of memory is elusive," and also the paper's statement that "it remains unclear however whether the engram is essentially cellular in nature or whether it is best described in terms of the changes in synaptic strength of contacts made onto and by engram cell."  Such statements show that the authors are just engaging in hand waving and guesswork. It's kind of like someone saying, "I know there are extraterrestrial spaceship bases in the solar system, but I don't know whether they are on the moon or on Mars." 

We then have a repetition of the groundless legend that some MIT group headed by Tonegawa did something to help establish the reality of engrams in the brain.  See my post here for why such claims are groundless. 

The paper then has about 10 diagrams that look like the ones below, with different color variations:



We have the caption "Different phases of memory formation and retrieval." The circles represent neurons, and the lines represent synapses. There are two line thicknesses, and we are told one thickness represents "weak synaptic strength," and the other thickness represents "strong synaptic strength." As a diagram trying to depict a neural formation of memories, the diagrams are a joke.  A neuron has an average of about 7000 synaptic connections with other neurons. And synapses can have any of a thousand different strengths. There is no way even the simplest learned information could be stored in the brain through anything like the shown diagrams. 

It is, in general, wrong to try to explain information storage by appealing to a mere process of strengthening. Strengthening is not storage. We know of many ways in which information can be stored, and none of them are cases of strengthening.

Below are some examples:
  1. People can store information by writing using a paper and pen. This does not involve strengthening.
  2. People can store information by using a typewriter to type on paper. This does not involve strengthening.
  3. People can store information by drawing pictures or making paintings. This does not involve strengthening.
  4. People can store information by taking photographs, either by using digital cameras, or old-fashioned film cameras. In neither case is strengthening involved.
  5. People can store information by using tape recorders. This does not involve strengthening.
  6. People can store information by using computers. This does not involve strengthening.
So basically every case in which we are sure information is being stored does not involve strengthening. What sense, then, does it make to claim that memory could be stored in synapses through strengthening?

In all of the cases above, information is stored in a rather similar way. Some unit capable of making a particular type of impression or mark (physically visible or perhaps merely magnetic) moves over or strikes a surface, and a series of impressions or marks are made on the surface. Such a thing is not at all a process of strengthening.

Consider a simple example. You have a friend named Mary, and you one day learn that Mary has a black cat. Now let us try to imagine this knowledge being stored as a strengthening of synapses. There is no way we can imagine such knowledge being stored by a strengthening of synapses. If you happened to have stored in your brain the knowledge that Mary has a black cat, it could conceivably be that a strengthening of synapses might allow you to more quickly remember that Mary has a black cat. But there is no way that the fact of Mary having a black cat could be stored in your brain through a strengthening of synapses.

Similarly, a simple example of a new memory (often tested in neuroscience experiments) is when a mouse is trained to fear a shock plate. There is no way we can imagine such knowledge being stored by a mere strengthening of synapses.

On and on the paper "The essence of the engram: Cellular or synaptic?" goes, continuing again to make observational claims that are not well founded.  An example is its claim, "Studies of engram cells have greatly expanded our understanding of the mechanisms underlying memory, but several questions remain unanswered." No, there have been no studies showing that there are any such things as "engram cells," and neuroscientists have no understanding whatsoever of any physical mechanism underlying memory.  Our neuroscientists are simply guilty of pretending to understand things they don't have any understanding of.  

The lack of any scientific basis becomes apparent when we look at how such papers define an "engram cell."  We read of no special characteristic of such a cell, such as a different appearance. We read of no physical change going on to make a cell an "engram cell." So how is an engram cell defined by such papers? It is typically defined as a cell that is part of some group of neurons and synapses that undergo "increased activation" when a memory is retrieved.  Almost all neurons in the brain transmit nerve impulses continuously, largely in a random fashion. So anyone scanning activity levels in the brain will always be able to find various cells in various parts of the brain having "higher activation." And anyone scanning the strengths of synapses will be able to find that a certain percentage (say 5%) are stronger than other ones.   So limiting yourself to checking electrical activity levels and synapse strengths, what is the difference between the observational result expected under the nonexistence of engrams (no brain storage of memories) and the observational result expected under the existence of engrams (brain storage of memories)? There isn't one. 

Our "Essence of the engram" paper then tells us, "Recent studies suggest that reactivation of engram cells induces the retrieval of memory and vice versa [4][34][42][97][98]. " I already explained in the bullet list above why the Reference 4 is to a junk science study. Here are the other   papers referenced:

  • Reference 34 is to the 2015 paper "Engram cells retain memory under retrograde amnesia." When we look at the end of the supplemental material, and look at figure s13, we find that the experimenters were using a number of mice that was equal to only 8 in one study group, and 7 in another study group.  Such a paltry sample size does not result in any decent statistical power, and the results cannot be trusted, since they very easily could be false alarms. The paper failed to use a blinding protocol, an essential for a paper like this to be taken seriously.
  • Reference 42 is the 2016 paper "Memory retrieval by activating engram cells in mouse models of early Alzheimer’s disease."  The paper states that “No statistical methods were used to predetermine sample size.” That means the authors did not do what they were supposed to have done to make sure their sample size was large enough. When we look at page 8 of the paper, we find that the sample sizes used were merely 8 mice in one group and 9 mice in another group. On page 2 we hear about a group with only 4 mice per group, and on page 4 we hear about a group with only 4 mice per group. Such a paltry sample size does not result in any decent statistical power, and the results cannot be trusted, since they very easily could be false alarms. The study therefore provides no convincing evidence of engram cells.
  • Reference 97 refers to the paper "Encoding of contextual fear memory in hippocampal–amygdala circuit." It's a junk science paper that used way-too-small study group sizes of only 6 mice and 11 mice.  The paper also used judgments of rodent freezing behavior to try to measure fear in animals, and all papers that use that faulty technique are junk science papers, for reasons I discuss at length hereThe paper failed to use a blinding protocol, an essential for a paper like this to be taken seriously.
  • Reference 98 refers to a paper that describes no original research, but merely references work by others. 

It is very clear what is occurring in papers such as this one.  Triumphal narratives are being given of scientists making progress in understanding a physical basis of memory. When we closely examine the papers that are cited to back up these boasts, we find that they are invariably weak shoddy studies guilty of Questionable Research Practices.

Citation of Junk Science Studies

This is largely how false narratives are perpetuated in science: by people citing poorly designed scientific research, and claiming that such research showed something, when the research failed to show any such thing because the research was so poorly done. 

The idea that human memories (which can last for 60 years) are stored in synapses (as maintained by the "Essence of the engram" paper criticized above) is untenable because synapses are so unstable, and are built from protein molecules that only last an average of a few weeks or less. An individual synapse and a dendritic spine do not last for years, and consist of proteins that only last for two weeks or less.  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% synapse 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." 

An additional reason for rejecting the synaptic theory of memory storage is that according to such a theory a memory could only be formed after a synapse was strengthened by proteins (something requiring at least minutes for protein synthesis). But humans can form a new memory instantly. Imagine if someone walks into your workplace naked or firing a gun. It wouldn't take you minutes to form a permanent memory of that. The memory would form instantly. But new proteins (such as would be needed to strengthen a synapse) could never form instantly. We know that the synthesis of new proteins requires minutes.  If forming new memories required the synthesis of new proteins, the brain would never keep up with sensory experiences which keep coming at you continuously. I can watch a 30-minute television drama, and then tell you every major thing that happened in the show. I wouldn't be able to do that if each new thing I saw required the synthesis of a new protein which required several minutes. 

In his Nautilus post “Here's Why Most Neuroscientists Are Wrong About the Brain,” C. R. Gallistel (a professor of psychology and cognitive neuroscience) points out the absurdity of thinking that mere changes in synapse strengths could store the complex information humans remember. Gallistel writes the following:

"It does not make sense to say that something stores information but cannot store numbers. Neuroscientists have not come to terms with this truth. I have repeatedly asked roomfuls of my colleagues, first, whether they believe that the brain stores information by changing synaptic connections—they all say, yes—and then how the brain might store a number in an altered pattern of synaptic connections. They are stumped, or refuse to answer....When I asked how one could store numbers in synapses, several became angry or diverted the discussion with questions like, 'What’s a number? ' ”

What Gallistel describes sounds dysfunctional: a pretentious neuroscientist community that claims to understand how memory can be stored in a brain, but cannot give anything like a plausible answer to basic questions such as “How could a number be stored in a brain?” or “How could a series of words be stored in a brain?” or “How could a remembered image be stored in a brain?” Anyone who cannot suggest plausible detailed answers to such questions has no business claiming to understand how a brain could store a memory, and also has no business claiming that a brain does store episodic or conceptual memories.

structure of bad science paper
                        Click to see left column more clearly

Postscript: The paper "Prevalence of Mixed-methods Sampling Designs in Social Science Research" has a Table 2 giving recommendations for minimum study group sizes for different types of research. The minimum subjects for an experimental study are 21 subjects per study group. Most of the studies mentioned above are experimental studies that used only about half of this minimum number.  The "case study" type mentioned below is a different type of study in which you merely document one or a few occurrences of some condition or situation, without trying to show a cause. 

minimum sample sizes