Our neuroscientists are getting nowhere in trying to show that there is a neural basis for human memory. But they have something they can rely on to help hide their lack of progress: pareidolia. Pareidolia is when you see patterns that aren't really there, like some guy examining his toast every day for years, and then one day saying, "I finally see the face of Jesus in my toast." A scientist conjuring up some pareidolia can make a nice-sounding progress report when no real progress has been made. I describe some examples of this in my post "Scientists Have a Hundred Ways to Conjure Up Phantasms That Don't Exist." Recently on a single screen of my I-Pad I saw three examples of neuroscientist pareidolia (which I identify here by using yellow text):
The first example was an article in Scientific American (copied from the journal Nature) entitled "Memories Are Made by Breaking DNA -- And Fixing It, Study in Mice Finds." The nonsense story is behind a paywall, but the Singularity Hub article here tells basically the same nonsense story. We read this silly narrative, not grounded in any solid research:
"DNA damage isn’t always detrimental. It’s been associated with memory formation since 2021. One study found breakage of our genetic material is widespread in the brain and was surprisingly linked to better memory in mice. After learning a task, mice had more DNA breaks in multiple types of brain cells, hinting that the temporary damage may be part of the brain’s learning and memory process."
As evidence for such claims, we have a link to the poor quality science paper "Formation of memory assemblies through the DNA-sensing TLR9 pathway." The paper is guilty of several bad examples of Questionable Research Practices (as are most experimental papers in cognitive neuroscience these days). One big sin of the paper is to use way-too-small study sizes such as only 5 mice, 6 mice and 7 mice. I once pointed out that the average number of authors in a typical neuroscience paper is about equal to the number of mice used in the resulting research; and I sardonically pointed out that it was as if scientists were following the ridiculous rule of "use only 1 mouse per neuroscientist." But in this case it seems even worse. We have 16 authors for a study that uses measly study group sizes of only about six mice per study group.
The study fails to mention any rigorous blinding protocol, and merely mentions that behavioral tests were performed blindly. For a study like this to be taken seriously, you would need to have much more of a blinding protocol, one also involving data analysis. Then there is the ridiculous use of "freezing behavior" judgments to try to judge whether memory recall has occurred in mice. For a full explanation of why all neuroscience papers that use this technique are unreliable, see my post "All Papers Relying on Rodent 'Freezing Behavior' Estimations Are Junk Science."
The title of the paper refers to "memory assemblies," but nothing has been done to show that any such thing was found. Here are all of the paper's references to "assemblies":
"Memories of individuals’ experiences are represented across assemblies of neurons in hippocampal and cortical circuits. Several mechanisms of formation and maintenance of these assemblies have been proposed...Recent focus has also been on the role of the interneuronal perineuronal nets (PNNs) in the stabilization of memory circuits through tightened control of inhibitory inputs to dedicated neuronal assemblies. Here we explored whether an overarching process could integrate stimulus-dependent and pre-existing mechanisms that underlie the commitment of neurons to memory-specific assemblies...The recruitment of individual neurons to assemblies is essential not only for encoding individual memories, but also for protecting them from streams of incoming information over time, ensuring stability and persistence of memory representations....Given the association of dsDNA damage with neurodegeneration, neurons undergoing learning-induced dsDNA breaks might be expected to be excluded from memory assemblies."
It is rather clear from these sparse and not-very-substantial uses of the word "assemblies" that nothing has been done to establish the existence of "memory assemblies" in the brain. Our authors are merely seeing some sort of something happening somewhere in the brain, and calling that a "memory assembly," without any justification of such a claim. The claim in the headline of the Scientific American article ("Memories Are Made by Breaking DNA -- And Fixing It") is a nonsensical-sounding claim that does not match any robust research. DNA does not store memories, and does not have any structure that could support the storage of human learned knowledge or human episodic memories. If scientists thought that DNA stored memories, they would try very hard to preserve the brains of dead people, and try and scan them to extract what the dead people had learned or experienced. Instead (except for rare cases) the brains of dead people are left for burial or cremation, just as if scientists thought that a dead brain was worthless. Thousands of human brains have been stored after death and studied, but no evidence has been found from such activity that memories are stored in brains, not in brain DNA nor anywhere else. For details, see my post "They Stored and Studied Thousands of Brains, But Still Failed to Show Brains Store Memories."
The next bunk story shown on the visual above is an NBC News story entitled "How the brain chooses which memories are important enough to save and which to let fade away." The story gives us this nonsensical claim: "Experiments in mice revealed that during waking hours, cells in the brain’s hippocampus spark in a specific pattern called 'sharp-wave ripples,' which tag important experiences for movement into long-term memory storage during sleep." We read this:
"As part of the research, Buzsáki and his colleagues put mice through a maze that had a sugary reward at the end for those that successfully reached it. Meanwhile, the researchers were monitoring the activity of nerve cells through electrodes implanted in the rodent brains that fed data into computer programs. They observed that as the mice paused to eat their treats, their brains sparked sharp-wave ripples that were repeated as many as 20 times. The daytime pattern of sharp-wave ripples was replayed during the night, a process that moved the experience into long-term memory."
Many people familiar with the drawbacks of EEG analysis will chuckle at the claims made above. The EEG is a device that can detect electrical activity from parts of the brain. When an EEG device is used, electrodes are placed next to different parts of the skull. The device will pick up a dozen or more different lines that show electrical activity in different parts of the brain.
What seems to be going on in the research mentioned by NBC News is mainly pareidolia. Having lots of EEG data that appear as an abundance of squiggly lines, anyone can find as many "ripples" as he wants. EEG ripples or squiggles are not any mechanism for storing memories. The people who have done this research are like someone wishing to believe that the ghosts of dead animals live in the clouds, and who (after examining thousands of photos of clouds) says that he sees something that looks like the shape of an animal. Anyone eagerly hoping to find some kind of pattern in a stream of noisy random data will be able to find a few cases that he can believe are instances of some pattern that he was hoping to find. This is pareidolia, not robust science.
The NBC News story has no link to a paper, but it is almost certainly referring to this 2024 paper co-authored by György Buzsáki (mentioned in the story), the paper "Selection of experience for memory by hippocampal sharp wave ripples." That's a poorly designed Questionable Research Practices study using a study group size of only six mice. A study like this should be taken seriously by no one unless it used a rigorous blinding protocol. But the text of the paper fails to use the word "blind" or "blinding." Because the study is not a pre-registered study, all of its analytics are just arbitrary post-hoc stuff meaning little. Anyone analyzing the constantly varying squiggles of brain wave data can pretty much see anything he wants to see. Studies of this type have little value unless they are pre-registered studies that follow a rigorous blinding protocol and have large study group sizes, and this study fails to be any of these things. The paper has a nonsensical title. Brain waves (sharp wave ripples or any other type) do not select anything. Brain waves are an epiphenomenon of brain activity, like cooking smells are an epiphenomenon of cooking activity. Claiming that brains waves select memories is as nonsensical as claiming that the scent from your cooking soup selects something.
The last of the three bunk stories is a Popular Science story entitled "How these feathery ‘memory geniuses’ remember where they stashed their food." The subtitle of the story has the groundless claim that "Chickadee brains make neural ‘barcodes’ to help recall thousands of hiding spots." We have a repetition of the false claim that "Scientists have long known that the brain's hippocampus is necessary for storing episodic memories like where a car is parked or food is kept." Read my post "Studies Debunk Hippocampus Memory Myths" for why that claim is untrue. We then have a reference to a mistitled paper "Barcoding of episodic memories in the hippocampus of a food-caching bird." It's one of endless scientific papers with a title that is not justified by anything reported in the paper. We have a misleading visual showing barcodes next to some chickadee birds, but this is just suggestive artwork not matching any data collected.
No discovery was actually made of anything like barcodes in the brain of these birds, and we can tell that funny business is going on by the paper's use of the word "barcodes" in quotation marks, as if to suggest "they're not really barcodes." In the caption to Figure 3 (which looks nothing like a barcode) we have this statement:
"Activity of neurons across caches after subtraction of the place code and the average cache response. We refer to this activity as the 'barcode.' ”
No robust research has occurred here. We have some arbitrary statistical invention (as arbitrary as calculating someone's weight in kilograms divided by his height in centimeters multiplied by his shoe size), and this is misleadingly referred to as a "barcode." The authors haven't found any evidence of anything like a barcode used by an animal brain. What is going on here is pareidolia, in which people see some pattern that isn't really there.
No study like this should be taken seriously unless a rigorous blinding protocol was followed, but no such thing was done. We merely hear that someone was blind to the sex of the birds, which is not the type of blinding that needed to be done.
Here (in Figure 4) is the best the authors can do to try and get some evidence of what they call "barcode reactivation." They claim that the two visuals on the left are similar, and that the two visuals on the right are similar. Probably the data was carefully filtered, massaged and selected to try and give the best match that could be found. But it's no good match at all. There's not even a repetition of a distinctive detailed pattern.
We should take this about as seriously as someone photographing thousands of clouds hoping to find the reappearance of an animal ghost, and showing us two clouds that both look like a tiny bit like a cat, and saying that this is evidence of an animal ghost reappearance. The visuals above aren't barcodes, and they don't look anything like barcodes. Here is what a barcode looks like:
Also without any merit is a recent press release with the headline "Researchers discover dynamic DNA structures that regulate the formation of memory." The press release is referring to the low quality paper "DNA G-quadruplex is a transcriptional control device that regulates memory." It's another mouse study, one using only a way-too-small study group of eight mice. Besides failing to use any blinding protocol (an essential for a paper like this to be taken seriously), the paper is another paper that hinges on subjective judgments of "freezing behavior" to try to measure fear in mice. Read here for why all such papers are junk science. In general, biology papers that refer to something chemical and use the word "regulate" are using unjustified and misleading language. Biochemical processes are incredibly complex, and individual chemicals are not regulators. The paper uses the word "control" rather than "controls," seemingly indicating that only one control animal was used. A well-designed experimental study would have used a minimum of 15 subjects per study group, and 15 subjects in the control group. The fact that major publications such as Newsweek did stories based on this low-quality research tells you something about the appalling lack of standards these days in science journalism.
We have only 8 mice in a study that has 19 authors. We should laugh whenever we encounter "One Mouse Per Scientist" researchers, and suspect any research they produce is poor research.
Our scientists are getting nowhere trying to back up the erroneous claim that memories are stored in the brain. No such memories can be found by microscopic examination of brain tissue, although we would have found them about 70 years ago if memories were stored in the brain, at about the same time DNA and the genetic code were discovered. To prevent us from noticing the dismal lack of progress in backing up claims that memories are stored in brains, we have a flow of poorly designed neuroscience studies on memory, studies failing to follow high standards of experimental science and honesty. That flow of studies is like a sewer pipe.
A kind of "anything is allowed" lying goes on these days in neuroscience press releases. A recent news story was entitled "Neuroscience Breakthrough Unveils How We Learn and Remember." The story was about some analysis of low-level changes in dendrites, and was promoting a paper that made no serious effort to link such changes to learning or memory. Previously scientists have usually claimed that learning occurs by changes in synapses, not dendrites. Chemical changes in both dendrites and synapses are slow, and cannot explain human learning, which can occur instantly.
When reading stories about neuroscience research, always assume that any uses of the word "breakthrough" or the phrases "unveils how" or "reveals how" or "shows how" are totally unjustified. 99% of the time such an assumption will be correct. A 2022 paper says this about neuroscience research: "The current landscape is characterized both by a lack of robust, validated standards and a plethora of overlapping, underdeveloped, untested and underutilized standards and best practices." The truth is: bad practices and poorly designed studies are more the rule than the exception in experimental neuroscience.
We should also remember that these days science-related clickbait is big business. Science-related stories with untrue but interesting-sounding claims lead to web pages with ads, and such ads make much revenue for the people funding the websites. So it's more than just pareidolia and paper-count-building and citation-count-building that explains all these junk stories: greed also plays a large part in it. What I call the scitainment industry (a mixture of science and entertainment) is very big business.
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