A type of article that shows up periodically in the literature of neuroscience is an article with some title such as "How the Brain Stores Memories." All such stories are bogus examples of groundless claims and hand-waving. No one has any understanding of how a brain could store memories. There is nothing in the brain that bears any resemblance to a device for writing memories; there is nothing in the brain that bears any resemblance to a device for storing memories for many years; and there is nothing in the brain that bears any resemblance to a device for retrieving memories.
Let's look at a recent example of this type of misleading article, and try to derive from t some principles about how people go about writing articles of this type. The article is one published in Forbes magazine. It is entitled "Timing Is Everything: How Our Experiences Become Memories." The author (William A. Haseltine) gives us an appalling example of someone pretending to understand things he does not understand. The article describes him as someone who "covers genomics and regenerative medicine." That's already a reason for suspecting his article is bunk. The author is apparently not an expert in the field of cognitive neuroscience or memory.
The first sentence of the article is: "Memories are created in a matter of seconds." That's correct; humans can form permanent new memories instantly (such as when a son or daughter learns that their parent has died). But Haseltine fails to put two and two together by realizing that this fact of instant memory creation rules out every explanation he attempts to give. The processes he describes (mainly synapse strengthening) are mostly sluggish processes requiring hours or days or many minutes. Processes so sluggish cannot be an explanation for the creation of a new memory, which can occur instantly. And since synapses are don't-last-for-years things built from proteins which have an average lifetime less than two weeks, unstable synapses cannot be an explanation for human memories that can reliably persist for 50 years.
Trying to explain how a brain could create a memory, Haseltine gives us this vacuous bit of hand-waving:
"From the moment the brain receives a sensory input (i.e. sight, sound, smell, etc.), neurons across the brain activate. Connections formed between these neurons give rise to dynamic neural networks called engrams. For example, when exploring a new city, an engram forms and continuously updates as you walk down various streets and turn corners. The moment you finally encounter the landmark you have been searching for, there is a burst of neural activity. Neurons that were activated seconds prior also increase their firing. Your brain consolidates this information into a mental map of how to get to the landmark. Engram formation, therefore, depends not only on neurons firing simultaneously but also on those that activate immediately before and after. This is known as behavioral timescale learning. "
The term "engram" is a vacuous bit of speculation that does not correspond to any well-establish scientific reality. The term means an alleged place where a memory is stored in the brain. Microscopic examination of brain tissue has never revealed the existence of any such thing as engrams. No one has ever found information someone learned in school by microscopically examining tissue from that person's brain. When biologists use the term "engram" they are speculating as wildly as when astrophysicists use the terms "dark matter" and "dark energy."
The account that Haseltine is giving here makes no sense, giving the reality of instant memory creation. Neural connections are the synapses between brains. It takes at least days for a new synapse to appear between neurons. So it is misleading bluffing for Haseltine to be telling us a story of the arising of "dynamic neural networks" as an explanation for memory creation.
Haseltine's next paragraph is just a mention of what goes on all the time in the brain, something that does nothing at all to explain memory creation. He says this:
"When a neuron activates, an action potential is generated. First, an electrical or chemical input stimulates a dendritic branch on the neuron. If the stimulus is strong enough, a branch becomes activated. The signal travels through the cell body and into the neuron’s axon. The activated axon releases chemical messengers called neurotransmitters to activate other cells in the network. Neural activation lasts just two milliseconds before the cell resets to allow another action potential to be generated."
Haseltine's next paragraph begins with a statement of fact, and two statements of utterly unproven speculation, wrongly stated as if they were fact. He states this:
"Generating action potentials is the basis of all brain activity. During learning, action potentials transmit signals that encode new experiences. A key region involved in this process is the hippocampus. Here, the brain consolidates short-term memories into long-term memory."
Yes, generating action potentials is the basis of all brain activity. No, there is no evidence that "action potentials transmit signals that encode new experiences." No one understands how things that humans see and hear could ever be encoded or translated into some format that would allow memories to be stored as synapse states or neural states. And there is no evidence that "the brain consolidates short-term memories into long-term memory" in the hippocampus or any other place. We merely know that human beings can have short-term memories that don't last for long and long-term memories that are permanent. Neuroscientists have no understanding of how a brain could create either short-term memories or long-term memories.
Haseltine goes on and on, mainly mentioning sluggish things that go on in the brain that are way too slow to credibly account for instant memory formation. For example, he states this:
"Repeated stimulation from a presynaptic neuron (the neuron sending the signal) to a postsynaptic neuron (the neuron receiving the signal) triggers molecular changes. First, neurotransmitters released by the presynaptic neuron bind to receptors on the postsynaptic neuron. When neurotransmitters bind to these receptors, channels open that allow calcium ions to enter the neuron."
Using Haseltine's article as an example, I can give a general outline for how people write bogus groundless articles with titles such as "This Is How Your Brain Stores Memories." The steps are basically these:
Step 1: Accumulate a list of things that are constantly going on in the brain, things that occur at various timescales ranging from seconds, hours or days.
Such a list may include:
(a) the transmission of action potentials across chemical synapses, something that is constantly occurring billions of times every second in the brain;
(b) the transmission of neurotransmitter chemicals across such synaptic gaps, something that constantly occurs;
(c) the strengthening of existing synapses, something that takes hours or days, and that goes on constantly regardless of whether anyone is learning or having sensory experiences;
(d) the creation of new synapses between neurons, something requiring days;
(e) the growth of new dendritic spines, which takes days;
(f) the changing in the size of dendritic spines, which takes between hours and days.
(2) Write some account of people acquiring a new memory or learning something, while blending the account with as many items on this list of types of neural activity, paying no attention to the time required for the types of neural activity.
This is exactly what Haseltine has done in his article. He has left out any discussion of the hours and days required for the processes he mentions, so that the reader will not notice what he has discussing is way, way too slow to explain instant human learning.
(3) Do a little science-jargon sprinkling, by doing things such as using the speculative term "engrams," by making vacuous uses of the terms "encoding" and "consolidation," and by maybe referring to some part of the brain such as the hippocampus or referring to some type of protein, claiming that it "plays a role" in memory formation.
Haseltine's only use of the word "encode" or "encoding" is vacuous, when he claims that "during learning, action potentials transmit signals that encode new experiences." The failure of neuroscientists to articulate any credible theory of neural encoding of memories, and their failure to show any evidence of such a thing occurring, are huge reasons for rejecting claims of the brain storage of memories. If memories were to be stored in brains, there would have to be some gigantically complicated encoding scheme a million times more complicated than the genetic code, something capable of converting the huge variety of things humans can learn into synapse states or brain states. There is no evidence that any such thing exists, and no neuroscientist has even stated a detailed theory of how such a thing could work. Haseltine also uses the neuroscience jargon word "consolidation" or "consolidate," but all of his references are vacuous, and never refer to any evidence for consolidation or a theory of consolidation.
(4) Refer to some recent paper, typically some poorly designed study using way too few subjects and poor methods, almost always something merely involving mice.
This is exactly what Haseltine. He refers us to only the poorly designed study "Dendritic, delayed, stochastic CaMKII activation in behavioural time scale plasticity," a mouse study that fails to even tell us how many mice were used. Whenever that happens, it is invariably because some way-too-small study group size was used such as only 7 mice. The study makes no mention of the use of blinding, meaning it is a Questionable Research Practices affair we should not trust. A study that fails to tell how many subjects it used should not be trusted about anything.
This scientific paper says the following:
This recent scientific paper says on page 9, "Overall, the studies reviewed here argue against, but do not completely rule out, a role for persistently self-sustaining CaMKII activity in maintaining" long term memory.
(5) Skip the issue of the lifelong persistence of memories, because scientists have no clue as to how that could occur in a brain with such high molecular turnover.
(6) Skip the issue of instant memory recall, since the brain has nothing like any of the things that enable that in machines, things such as addressing, sorting and indexing.
