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.
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