The 4 Nonsensical Parts of the Tale Your Brain Instantly Retrieved an Answer Learned Long Ago

There are some "show stopper" difficulties in the idea that a human uses his brain to answer a question that arises in his mind. But an interesting question is: is such an idea only partially nonsensical, or is it almost entirely nonsensical? I will argue now that the story that you use your brain to instantly retrieve an answer you learned long ago and stored in your brain is pretty much entirely nonsensical. What I mean by this is that when we break down the idea into a series of parts, we find that each of the parts is unworkable or incoherent or unbelievable. 

Let's analyze the tale of you using your brain to think of a question, and then instantly recalling its answer (learned long ago) by using your brain, looking at each of the component parts of such a tale.

Part 1: The Nonsensical Idea That a Question Arises in Your Brain  

There is nothing illogical about the idea that a question arises in a mind. A question is just an example of an idea, and humans can have ideas. So suppose I ask myself, "How was it that I learned how to swim?" That's equivalent to the idea that I somehow learned to swim, and that I might be able to recall how that happened.  The problem comes when we try to get a neural account of this question arising in my mind.  Ideas cannot be explained by brain activity. No neuroscientist has ever told a coherent credible tale of an idea arising in your brain. There is no evidence that brains change their state when someone has an idea. 

You can imagine some computer that processes data, and has a particular screen that is labeled "my current thought." The computer might retrieve different words, and display them on that screen. So at a particular moment you might see the screen showing, "Where did Napoleon Bonaparte die?" We could give some explanation of how such a question came to appear on such a screen. But in the brain there is nothing like this physical arrangement.  There is no little special area of the brain devoted to holding a person's current thought. 

Can we imagine, perhaps, some random part of the brain where there is written some words that correspond to the question in your mind? There is no evidence that words or letters ever physically appear in the brain. You cannot scan any part of the brain and see any words or letters. So the idea of a question arising in your brain (as opposed to your mind) is nonsensical. There is no credible neural account we can give of a question arising in the brain.

Part 2: The Nonsensical Idea That the Answer You Learned Long Ago Was Converted to a Neural State or Synapse State

To continue our examination of the idea of the brain retrieving an answer that you learned long ago, we must imagine that long ago you learned some answer that you converted into some brain state or synapse state. For example, if you are to give a neural account of you recalling the answer to the question of how many states there are in the United States, you must imagine at some time you were told that the United States has 50 states, and that you stored such a fact as a brain state. But such an idea is nonsensical. We can imagine no neural states or synapse states that could store as simple a sentence as the sentence "The United States has 50 states." 

Nowhere in a brain or in synapses is there a writing area in which words can be written in any form resembling printed words or written words. And there's nothing in the brain corresponding to a pencil or pen that would write at a particular position. On the hard drive of a computer like existed in the year 2000, information writing occurred because the disk spun around, and there was a read/write head that could move to a particular spot on the disk to read or write. There's nothing like that in the brain. In the architecture of the brain, there's nothing like any cursor or current writing position, and there's nothing resembling a read/write head. So how could information ever be written in some particular spot of the brain?

You don't get around this by imagining that the brain stores some learned information by splitting it up into different parts, and storing the different parts in different places of the brain. That just makes the problem worse, creating new problems of how such a division could take place, why those particular scattered places would be chosen for storage, and how information so scattered could be reassembled instantly when you instantly remember something. Similarly, if I can't explain how some dog could write what happened to it today by writing in one of the books in my book case, I don't make that problem easier by speculating that maybe the dog split his account up so it was stored in not one of my books but five of my books. 

Then there's the problem that proteins are the work horses of the body, but a language such as English and the alphabet it uses are less than 3000 years old; and there has been no change in brain structure or brain proteins during that time. So how could your brain ever write something in some language that didn't exist when the latest proteins of the brain appeared? 

Humans remember skills and emotions and facts and images in a thousand different forms. We can imagine no translation scheme by which all such things could be converted to brain states or synapse states. Can we get around this by supposing, for example, that your answer to the question of how many states are in the United States is stored as the original sense impressions you had when you learned that? No, we can't. I remember endless thousands of things that I have learned without remembering the original sense impressions I had when learning such things. For example, if you ask me how many states are in the United States, I simply remember "50," but do not at all remember myself as some tiny child in a school room hearing the teacher teach me that.  

Although we hear neuroscientists talk longingly about one day discovering a neural code by which learned information could be converted to neural states, no such thing has been found. There isn't even a substantive detailed theory as to how such a thing could happen. A neuroscientist cannot even give you a detailed speculative explanation as to how exactly as simple a phrase as "my dog has fleas" could be stored as neural states. Any speculations you may read on this topic tend to be jargon-decorated hand waving. In short, the idea that the answer that you learned long ago was stored as a neural state or a synapse state is nonsensical. 

Part 3: The Nonsensical Idea That the Answer You Learned Long Ago Persisted for Many Years as Some Stored Knowledge in a Brain

The brain is an area of heavy molecular turnover. The proteins that make up the synapses of the brain have average lifetimes of less than two weeks. Synapses are so small that it is hard to directly track their lifetimes. But we know that such synapses are attached to tiny structures in the brain called dendritic spines. And we know that such dendritic spines don't last very long. 

Dendritic spines last no more than about a month in the hippocampus, and less than two years in the cortex. This study found that dendritic spines in the hippocampus last for only about 30 days. This study found that dendritic spines in the hippocampus have a turnover of about 40% each 4 days. This 2002 study found that a subgroup of dendritic spines in the cortex of mice brains (the more long-lasting subgroup) have a half-life of only 120 days. A paper on dendritic spines in the neocortex says, "Spines that appear and persist are rare." While a 2009 paper tried to insinuate a link between dendritic spines and memory, its data showed how unstable dendritic spines are.  Speaking of dendritic spines in the cortex, the paper found that "most daily formed spines have an average lifetime of ~1.5 days and a small fraction have an average lifetime of ~1–2 months," and told us that the fraction of dendritic spines lasting for more than a year was less than 1 percent. A 2018 paper has a graph showing a 5-day "survival fraction" of only about 30% for dendritic spines in the cortex.  A 2014 paper found that only 3% of new spines in the cortex persist for more than 22 days. Speaking of dendritic spines, a 2007 paper says, "Most spines that appear in adult animals are transient, and the addition of stable spines and synapses is rare." A 2016 paper found a dendritic spine turnover rate in the neocortex of 4% every 2 days. A 2018 paper found only about 30% of new and existing dendritic spines in the cortex remaining after 16 days (Figure 4 in the paper).

The main theory of memory storage in the brain involves claims that memories are stored in synapses. But what we know about synapses and dendritic spines and their instability and heavy turnover is inconsistent with the fact that memories can persist for many years. 

 Part 4: The Nonsensical Idea That You Instantly Found the Answer You Learned Long Ago That Was Stored in Your Brain

Now we come to what is perhaps the most nonsensical part of all: the idea that your brain instantly found some answer that was learned years ago.  Humans make things that allow the instant retrieval of information: things such as books and computers. We know the kind of underlying features that such things have that allow us to instantly retrieve information using such things. The four pillars of instant information retrieval using physical devices are addressing, sorting, indexing, and focusing. 

The four pillars of a physical instant retrieval of knowledge

For example, consider the simple case of a history book. You can find an answer about some historical topic instantly by using the index of the book to look up some topic, and then going to the appropriate page.  This requires addressing (that pages have particular page numbers), sorting (that the pages be sorted in numerical order), indexing (that there be an index), and focusing (the ability of your eyes to focus on the index entry or on a part of a page, and the fact that the book can only be opened to two pages at a time).  With an encyclopedia of alphabetically sorted topics, you can retrieve information instantly without either the indexing or the addressing. But with such a book you still need at least sorting and focusing (the focusing of your eyes on a particular page, and the design of the book which gives a kind of focusing by restricting the book to display two pages at a time). 

Similar things occur when you retrieve information using a computer. When you look up something using a computer, your computer is internally using addressing and indexing, or accessing some database that uses addressing and indexing. And your computer or I-Pad or smartphone has a focusing mechanism: a screen that limits things so that only a particular rectangle of information is displayed  Also, the information retrieval requires your eyes to be focusing on the screen. 

So I have reviewed some of the things required for instant information retrieval to physically occur. Does the brain have any of these things? It does not. There is no addressing in a brain. Particular neurons do not have neuron numbers or neuron addresses, and particular synapses do not have synapse numbers or synapse addresses.  There is also no physical sorting in the brain. The physical structure of the brain makes a sorting of synapses or neurons impossible. Since each neuron has many connections which anchor it to a particular place, and most synapses are anchored in various ways such as being anchored to dendritic spines, there can be no physical sorting in the brain.  Consequently there can be no indexing in a brain, since indexing requires sorting and addressing. 

Is there at the very least some kind of physical focus mechanism in the brain? There is no sign of any such thing. We can speculate about how brains of extraterrestrial creatures might have some kind of focus mechanism. We can imagine some moving read unit that might move around from one part of the creature's brain to another; and when such a read unit was located at one particular part of the brain, there would be a focus on that part.  But no such thing exists in the human brain. Physically the brain shows zero signs of ever focusing on one particular part of the brain. 

A web page discusses the physical changes that occur when an eye focuses:

"Your curved cornea bends the light into your eye. Your lens changes shape to bring things into focus. When you look at things that are far away, muscles in your eye relax and your lens looks like a slim disc. When you look at things that are close, muscles in your eye contract and make your lens thicker." 

There is no sign of any physical changes occurring in the brain  when you remember some thing you learned long ago. There is no physical sign of any focusing occurring in the brain. Don't be fooled by brain scan visuals that use "lying with colors" visuals designed to make you think that some part of the brain "lights up" during some particular activity. Such visuals misleadingly depict changes in brain blood flow no greater than about 1 part in 200, and are not any evidence of a brain focusing on some particular part to get data, but are mere signs of tiny random fluctuations. Using the same type of techniques, you could make the same type of visuals showing changes in blood flow in your liver while you were remembering something. 

We know the kind of things that enable instant information retrieval in objects humans make: things such as addressing, sorting, indexing and focusing. No such things occur in the brain when you remember some answer you learned long ago. So how could a brain ever instantly retrieve some fact you learned many years ago? It could not. That would be like instantly finding just the right palm-sized index card in an Olympic-sized swimming pool filled to the top with index cards.  

I have examined four different parts involved in the tale that you use your brain to retrieve some answer you learned long ago and stored in your brain. All of the parts are nonsensical. Similarly, if we were to analyze the different parts involved in a tale of someone holding a big soap bubble that lifts him up and carries him to live a happy life on  Venus, we would find that each of the different parts of the story is nonsensical. 

There is a much better account that makes sense: the account that you have a soul that is equipped with a nonphysical repository of knowledge and memory. You can therefore instantly retrieve things you have learned, because there is no physical retrieval involved. And you can remember things that you learned very long ago, because the repository does not consist of short-lived structures subject to heavy molecular turnover.  And you can instantly form new memories and learn new things, because you don't have to wait minutes or hours for protein synthesis to occur each time you learn something.  And should it be that your brain shuts down temporarily during cardiac arrest, you may (like very many people who had the same thing happen) be able to tell a very vivid recollection of a near-death experience, because the electrical inactivity of your brain will not stop you from forming new memories. And if this occurs you may well remember observing your body from far away from it, like so many others having near-death experiences and out-of-body experiences, because your brain never was the source of your self.