Several of my previous posts have examined the unsuccessful attempts of neuroscientists to give credible answers to basic questions that might be asked by a person believing their claims that brains produce minds and that brains store memories:
- In my previous post "Exhibit A Suggesting Scientists Don't Understand How a Brain Could Store a Memory," I examined an article by a neuroscientist in The Guardian, one entitled "What happens in your brain when you make a memory?" I showed the lack of credibility in the supplied answer, which wasn't even a self-consistent one, with the author switching from a claim that memories are stored in synapses to the different claim that memories are stored in neurons.
- In my previous post "Exhibit A Suggesting Scientists Don't Understand How a Brain Could Retrieve a Memory," I looked at the answers given at an expert answers site to the question "How are memories retrieved in the brain?" In general we got the impression that none of the writers had a credible story to tell.
- In my previous post "Exhibit B Suggesting Scientists Don't Understand How a Brain Could Retrieve a Memory," I looked at the glaring inadequacies of a paper entitled "The neurobiological foundation of memory retrieval." I pointed out the authors simply ignore the whole speed problem of explaining instant memory recall. Their paper makes no mention of such a thing, and doesn't use words such as "speed" or "quick" or "fast" or "instant" or "instantaneous." The authors also ignore the issue of how a brain could decode (during memory retrieval) encoded information stored in a brain. Their paper does not use the words "decode," "decoding" or "translate." The paper merely refers in passing to some research they claim has "potentially interesting translational implications," but give no details to clarify such a claim. Nor does the paper have any discussion of some theory of a read mechanism that could be used to read memories from brains. Searching for the word "read" in the paper produces no relevant sentences.
- In my previous post "Exhibit A Suggesting Scientists Have No Understanding of How a Brain Could Imagine Anything" I discussed why a long essay by neuroscientist Andrey Vyshedskiy failed to supply any neural explanation for how imagination can occur.
- In my previous post "More Indications Scientists Don't Understand How a Brain Could Think or Remember" I discussed the failures of neuroscientists to give any credible neural theory of thinking, creativity, or recall.
Let's look at what is in a computer, and whether that matches anything known to exist in the brain. No one can ever give any explanation of how a material thing could produce an abstract idea. We do, however, have some idea of how certain machines are able to process data in a way that some attempt to compare to thinking. Although they are incapable of conscious thought, computers can do logic and data processing by means of things such as these:
(1) a central processing unit, a small part of a computer with a unique architecture unlike any other part of the computer;
(2) an operating system, an extremely complex library of software functions of general usefulness (UNIX, Linux, Android and Windows are examples), one requiring man-years of purposeful labor to produce;
(3) application programming code that follows various syntax rules so it can be executed by an interpreter or a compiler (nowadays all computers have on them application software that required years of human effort to produce);
(4) things such as "if/then" logic, variables that store text or numbers, and programming control structures such as loops.
No such things exist in the brain. With the exception of the genetic processing apparatus that exists throughout the body, which processes only lists of amino acids in DNA, there is no place in the brain where some sequence of instructions is processed the way a computer processes sequential instructions. The brain has nothing like a computer operating system, and no application programming code. There is no place where we see "if/then" logic being processed, and we can find no place in a brain where variables store values such as numbers and text strings. We cannot detect in the brain anything like the engineering that a computer uses to process information. It has been pointed out by one expert that current neuroscience theories are not even able to explain how a brain could store a single number. Except for genetic information that does not contain learned knowledge, there is no sign of anything in the brain that could store or retrieve information. Examining brain tissue with the most powerful microscopes, no trace can be found of anything a person learned or any memory of an experience.
So to say a brain is a computer is to tell a falsehood as outrageous as claiming that the brain is an interstellar spaceship. We know the type of things that computers have, and the brain does not have such things. In a poll of neuroscientists, they were asked whether they agreed with the claim that the brain is like a computer, with data collection and processing. 47% said yes, 35% said no, and 18% said they did not know. There is obviously no clear neuroscience basis for claiming the brain acts like a computer.
Next Robinson gives us this analogy which offers no insight on how a brain could think anything:
"Imagine your brain as a busy city with lots of streets and buildings. Each part of the brain has a specific job to do, just like certain areas of a city or certain buildings serve different purposes. When you have a thought, it’s like a message traveling through the city, passing from one area to another."
This doesn't get us anywhere in the way of explanation. The question is how a thought arises, and you don't do anything to explain that by saying a thought moves around from one place to another. There is also no neuroscience basis for claiming that thoughts are transmitted by brain signals. Eavesdropping on brain signals by using techniques such as EEG readings, no one has ever been able to detect anything like a thought traveling around.
Robinson then tells us this:
" When you have a thought, neurons in your brain fire up and create electrical impulses. These impulses tend to travel along similar pathways and release tiny chemicals called neurotransmitters along the way. These neurotransmitters are like the construction crew that builds the roads, making it easier for the messages to be delivered."
There is no neuroscience justifying these claims. It is not true that electrical impulses arise in the brain only when you are thinking. Instead, electrical impulses are constantly traveling all over the brain, throughout every region, regardless of whether you are thinking or not. According to the site here, the average neuron transmits an electrical signal at the rate of between about 10 times per second and once every two seconds. When a human being thinks of nothing at all, his brain has the same electrical activity as when he is thinking. As for Robinson's claim that neurotransmitters are like a construction crew that builds roads, it is a false and misleading claim. Neurotransmitters do nothing to construct structures in the brain. Your neurotransmitters are no more a construction crew than your emails and instant messages are a construction crew.
The first visual on the page here shows EEG readings for a human during 10 seconds of eyes closed resting activity. We see readings from 30 different electrodes. Each reading shows a squiggly line. Such lines are brain waves that result from random firing of neurons when no thinking or recall activity occurred. The same thing is shown in Figure 1 of the paper here. So you don't explain thinking by mentioning neurons firing. There is always a great abundance of neurons firing in the brain, even when you are not thinking about anything. There is no evidence that neurons fire more often when you think.
Figure 6 of the paper here ("A test-retest resting, and cognitive state EEG dataset during multiple subject-driven states") shows brain waves for subjects in five differing mental states: an eyes closed rest state, an eyes open rest state, a state of recalling in the mind a song, a state of recalling the previous days events, and a state of doing mental math by subtracting backwards from 5000. We have lines representing each of these states, with each state shown in a different color. The lines look almost identical. Figure 7 shows the same data, represented by a different technique. We get the impression of very little difference in neural firing rates when someone changes from resting his mind to doing the thinking needed for math.
Figure 2 of the paper here compares firing rates of hippocampus neurons in rats, during sleep and an awake state. They look about the same, varying from once every ten seconds to ten times per second. When you do a Google image search for "neural firing rates in different activities," you will see diagrams that tend to show a bell-shaped curve, with the curve varying from about .1 times per second to 10 times per second. The graphs are usually expressing in hertz, which means a rate of 1 time per second.
Robinson then repeats the unfounded claim that learning results in synapse strengthening, and that brains store memories. I won't rebut that here, because it has nothing to do with the topic under discussion, which is thinking.
We are rather clearly getting nothing in the way of a neural explanation for thinking when Robinson makes a statement like this:
"Creativity is another superpower of the brain. When you let your imagination run wild, your brain can come up with new ideas, stories and inventions. Artists, writers and scientists all use their creative brains to explore new possibilities and solve problems.
Have you ever experienced a 'eureka' moment when a brilliant idea pops into your head out of nowhere? That’s your brain’s way of connecting the dots and coming up with a solution."
The rest of the article is entitled "Keeping Your Brain Healthy," and offers nothing in the way of an explanation of how brains could think. We are left with nothing in the way of any explanation of how a brain could think.
Below are some relevant quotes by scientists:
- " We don't know how a brain produces a thought." -- Neuroscientist Saskia De Vries (link).
- "You realize that neither the term ‘decision-making’ nor the term ‘attention’ actually corresponds to a thing in the brain." -- neuroscentist Paul Ciskek (link).
- "We know very little about the brain. We know about connections, but we don't know how information is processed." -- Neurobiologist Lu Chen.
- "Computers really do operate on symbolic representations of the world. They really store and retrieve. They really process. They really have physical memories. They really are guided in everything they do, without exception, by algorithms. Humans, on the other hand, do not — never did, never will. Given this reality, why do so many scientists talk about our mental life as if we were computers?" -- Senior research psychologist Robert Epstein.
- "The neuroscientific study of creativity is stuck and lost." -- Psychologist Arne Dietrich, "Where in the brain is creativity: a brief account of a wild-goose chase."
- "How creative ideas arise in our mind and in our brain is a key unresolved question." -- nine scientists (link).
- "The central dogma of Neuormania is that persons are their brains....Basic features of human experience...elude neural explanation. Indeed, they are at odds with the materialist framework presupposed in Neuromania. Many other assumptions of Neuromania -- such as that the mind-brain is a computer -- wilt on close inspection. All of this notwithstanding, the mantra 'You are your brain' is endlessly repeated. This is not justified by what little we know of the brain, or more importantly, of the relationship between our brains and ourselves as conscious agents." -- Raymond Tallis, Professor of Geriatric Medicine, University of Manchester, "Aping Mankind," page xii (link).
- "The passage from the physics of the brain to the corresponding facts of consciousness is unthinkable. Were we able even to see and feel the very molecules of the brain, and follow all their motions, all their groupings, all their electric discharges if such there be, and intimately acquainted with the corresponding states of thought and feeling, we should be as far as ever from the solution of the problem,...The chasm between the two classes of phenomena would still remain intellectually impassable." -- Physicist John Tyndall (link).
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