Sunday, November 27, 2022

Exceptionally Fast Thinking Cannot Be Explained by Slow Brains Like We All Have

Information travels about in a modern computer at a speed thousands  of times faster than nerve signals travel in the human brain. If you type in "speed of brain signals" into the Google search engine, you will see in large letters the number 286 miles per hour, which is a speed of 128 meters per second. This is one of many examples of a dubious claim which sometimes pops up in a large font at the top of the Google search results. The particular number in question is an estimate made by an anonymous person who quotes no sources, and one who merely claims that brain signals "can" travel at such a speed, not that such a speed is the average speed of brain signals. There is a huge difference between the average speed at which some distance will be traveled and the maximum speed that part of that distance can be traveled. For example, while you may briefly drive at 40 miles per hour while traveling through Manhattan or Paris, your average speed will be much, much less because of traffic lights and stop signs. 

A speed such as about 100 meters per second is the maximum speed at which such a nerve signal can travel, when a nerve signal is traveling across what is called a myelinated axon. Below we see a diagram of a neuron. The axons are the tube-like parts in the diagram below.

axon

The less sophisticated diagram below makes it clear that axons make up only part of the length that brain signals must travel.

axons

There are two types of axons: myelinated axons and non-myelinated axons (myelinated axons having a sheath-like covering shown in blue in the diagram above). According to this article, non-myelinated axons transmit nerve signals at a slower speed of only .5-2 meters per second (roughly one meter per second).  We are told that higher thought comes from the cortex of the brain. But most of the axons in the cortex are not myelinated. 

Nerve signals must also travel across dendrites and synapses, which we can see in the diagrams above. It turns out that nerve signal transmission is much slower across dendrites and synapses than across axons. To give an analogy, the axons are like a road on which you can travel fast, and the dendrites and synapses are like traffic lights or stop signs that slow down your speed.

According to neuroscientist Nikolaos C Aggelopoulosthere is an estimate of 0.5 meters per second for the speed of nerve transmission across dendrites (see here for a similar estimate). That is a speed 200 times slower than the nerve transmission speed commonly quoted for myelinated axons. According to Bratislav D. Stefanovic, MD, the conduction speed across dendrites is between .1 and 15 meters per second. Such a speed bump seems more important when we consider a quote by UCLA neurophysicist Mayank Mehta: "Dendrites make up more than 90 percent of neural tissue."  Given such a percentage, and such a conduction speed across dendrites, it would seem that the average transmission speed of a brain must be only a small fraction of the 100 meter-per-second transmission in myelinated axons. 

Besides this “speed bump” of the slower nerve transmission speed across dendrites, there is another “speed bump”: the slower nerve transmission speed across synapses (which you can see in the top “close up” circle of the first diagram above). There are two types of synapses: chemical synapses and electrical synapses. The parts of the brain allegedly involved in thought and memory have almost entirely chemical synapses. (The sources here and here and here and here and here refer to electrical synapses as "rare."  The neurosurgeon Jeffrey Schweitzer refers here to electrical synapses as "rare."  The paper here tells us on page 401 that electrical synapses -- also called gap junctions -- have only "been described very rarely" in the neocortex of the brain. This paper says that electrical synapses are a "small minority of synapses in the brain.")

There is a scientific term used for the delay caused when a nerve signal travels across a synapse. The delay is called the synaptic delay. According to this 1965 scientific paper, most synaptic delays are about .5 milliseconds, but there are also quite a few as long as 2 to 4 milliseconds. A more recent (and probably more reliable) estimate was made in a 2000 paper studying the prefrontal monkey cortex. That paper says, "the synaptic delay, estimated from the y-axis intercepts of the linear regressions, was 2.29" milliseconds. It is very important to realize that this synaptic delay is not the total delay caused by a nerve signal as it passes across different synapses. The synaptic delay is the delay caused each and every time that the nerve signal passes across a synapse. 

Such a delay may not seem like too much of a speed bump. But consider just how many such "synaptic delays" would have to occur for, say, a brain signal to travel from one region of the brain to another. It has been estimated that the brain contains 100 trillion synapses (a neuron may have thousands of them).  So it would seem that for a neural signal to travel from one part of the brain to another part of the brain that is a distance away only 5% or 10% of the length of the brain, that such a signal would have to endure many thousands of such "synaptic delays" requiring a total of quite a few seconds of time. 

Humans can recall information instantly given a one-word prompt, but such an ability is inexplicable given the physical limitations of brains. We know the type of things that make instant data retrieval possible in computers: features such as indexing, sorting and addressing. The brain has no such features. Given its physical nature, trying to remember anything by retrieving information from a brain would be like trying to find a needle in a haystack. 

Because of all of these reasons, it seems that brains are far too slow to explain normal fast thinking and normal fast recall.  Human recall of learned information typically occurs instantaneously.  We see this on the show "Jeopardy," where contestants typically give correct answers within a second or two after being prompted about obscure information.  For example, when read the prompt "The battle that had a fateful mistake known as Pickett's Charge," contestants within 1 second may start to answer "What is Gettysburg?" And if I ask some old people "Which US president succeeded Jimmy Carter?" it will take only a second before I hear an answer of "Reagan."

Humans can also think very fast. There are many historical cases of math prodigies that could calculate with incredible speed and accuracy.  The passage below describes the blazing fast calculation powers of Zerah Colburn:

"This child undertook, and completely succeeded in, raising the number 8 progressively up to the sixteenth power. And in naming the last result, viz.: 281, 474, 976, 710, 656, he was right in every figure. He was then tried as to other numbers consisting of one figure, all of which he raised (by actual multiplication, and not by memory) as high as the tenth power, with so much facility and dispatch that the person appointed to take down the results was obliged to enjoin him not to be so rapid. With respect to numbers consisting of two figures, he would raise some of them to the sixth, seventh and eighth power....He was asked the square root of I06,929, and before the number could be written, he immediately answered, 327. He was then required to name the cube root of 268,336,125, and with equal facility and promptness he replied, 645. Various other questions of a similar nature, respecting the the roots and powers of very high numbers, were proposed by several of the gentlemen present, to all of which he answered in a similar manner. One of the party requested him to name the factors which produced the number 247,483: this he immediately did by mentioning the numbers 941 and 263 — which, indeed, are the only two numbers that will produce it...One of the gentlemen asked him how many minutes there were in forty-eight years; and before the question could be written down, he replied 25,228,800; and instantly added that the number of seconds in the same period was 1,513,728,000."

The passage below tells us about the incredibly fast calculation speed of  Jacques Inaudi, born in 1867:

"In his exercises of mental calculation, Mr. Inaudi is remarkable in two particulars, the complexity of his work and the rapidity with which he completes it. The greater number of questions given to him contain many figures. He will add in his head two numbers consisting of twelve figures each ; he will multiply two numbers composed of eight figures ; he will tell how many seconds there are in any promiscuously chosen number of years, months, days, and hours. These operations demand that he shall hold in his memory the exact problem and the partial solutions up to the time when the complete result is found. For such a considerable work as this, Mr. Inaudi gives an extremely short time, so short, indeed, as sometimes to produce the illusion of instantaneity. The following paragraph has been published concerning him. ' He adds in a few seconds seven numbers of eight or ten figures each; he subtracts one number from another each composed of twenty-one figures in less than a minute; he finds as rapidly the square root or the cube root of numbers consisting of from eight to twelve figures, if these numbers are perfect squares or cubes; it takes a little longer for the last-named work if there is a remainder necessitating a fractional part to the answer. He finds with incredible celerity the sixth or the seventh root of large numbers. He will multiply or divide in less time than it takes him to announce the results. As an example of what has been said, we give the following: He was asked the number of seconds in 18 years, 7 months, 21 days and 3 hours. The response was given in thirteen seconds."

Page 250 of the May 21, 1880 edition of The Spiritualist has a story about Jacques Inaudi, spelling his name Inodi.  We read this about the boy who was then a mere adolescent:

"Persons who desire to know the number of minutes and seconds that they have lived do not puzzle him in the least; almost instantaneously he gives the answer. That which appeared most to fatigue him was simple multiplication, rather a long sum, it is true. He was asked to multiply 78,965,428 by 56,789. Not having these numbers before his eyes, and moreover, not being able to read, it was necessary to repeat them two or three times, until having remembered them, he could repeat them alone himself. A moment after, he dictated this exact and long product, 4,484,367,690,692, not however, without having thought (cherehe) a little, with an evidently laborious effort, which proves that he is not aided by mediumship.

In the twentieth century the legendary mathematician John von Neumann was famous for his lightning-fast problem solving abilities. When he was six years old, he could divide two eight-digit numbers in his head. The wikipedia.org article on him mentions some of the greatest thinkers of his time saying that von Neumann was the fastest thinker they had ever met. We read this story about a problem posed to von Neumann:

"Two bicyclists start 20 miles apart and head toward each other, each going at a steady rate of 10 mph. At the same time a fly that travels at a steady 15 mph starts from the front wheel of the southbound bicycle and flies to the front wheel of the northbound one, then turns around and flies to the front wheel of the southbound one again, and continues in this manner till he is crushed between the two front wheels. Question: what total distance did the fly cover? ...When the question was put to von Neumann, he solved it in an instant, and thereby disappointed the questioner: 'Oh, you must have heard the trick before!' 'What trick?' asked von Neumann, 'All I did was sum the geometric series.' "

Neelakantha Bhanu Prakash has been called the world's fastest calculator, and can do things such as multiply 869,463,853 times 73 correctly in only 26 seconds, giving an answer of 63,470,861,269. This is despite having a very serious head injury which required 86 stitches, and left him with a prominent scar on his forehead. According to the Guinness Book of World Records, "Scott Flansburg of Phoenix, Arizona, USA, correctly added a randomly selected two-digit number (38) to itself 36 times in 15 seconds without the use of a calculator on 27 April 2000 on the set of Guinness World Records in Wembley, UK." 

A scientific paper tells us this about the autistic savant Daniel Tammet:

"DT [Daniel Tammet] speaks 10 languages, including Estonian and Finnish, has invented his own language (Manti) and learnt Spanish in one weekend. He performs mathematical calculations at lightning speed, including multiplying six-digit numbers together. He commented that 31, 19, 79 and 1979 are all prime numbers, an indication of how he sees patterns in numbers very rapidly. As mentioned earlier, as part of a formal competition he recited Pi to 22,514 decimal paces, earning the title of European champion."

The book Bright Splinters of the Mind  by Beate Hermelin is about autistic savants, those with special skills despite seeming to be largely defective in some areas of mental functioning.  On page 63 of the book we read this about a gifted subject: "Christopher can understand, talk, read, write and translate from Danish, Dutch, Finnish, French, German, Greek, Hindi, Italian, Norwegian, Polish, Portuguese, Russian, Spanish, Swedish, Turkish and Welsh." On page 300 the book mentions twins who could recall up to 300 digits. On page 17 the author reports being introduced to a 13-year-old boy who immediately asks him his birthday:

"When I told him it was 7 August, he said instantly, 'That was on a Wednesday in 1940, and in 2004 it will be on a Wednesday again.' I was stunned, and of course had no idea whether he was right. (He was!)" 

Quite a few such accounts of instantaneous human calendar calculation  are found in this book and a book by Darold A. Treffert. Below are statements made by Treffert in his very interesting book Extraordinary People: Understanding Savant Syndrome:

  • In 1788 the slave Thomas Fuller (who could neither read nor write) was asked "How many seconds has a man lived who is 70 years, 17 days and 12 hours old?"  90 later seconds Fuller gave a correct reply of 2,210,500,800. His obituary stated that "he could give the number of months, days, weeks, hours, minutes, and seconds in any period of time that any person chose to mention, allowing in his calculation for all the leap years that happen in the time."
  • A Dr. J. Langdon Down described a 12-year-old boy who could multiply any three numbers by any other three numbers, as quickly as Down could write the six numbers on paper.
  • A Dr. Alfred F. Tredgold mentioned a person who could give the square root of any four digit number in an average of four seconds, and who could give the cube root of any six-digit number in about six seconds. He said that when the same person "was asked about how many grains of corn there be in any one of 64 boxes, with 1 in the first, 2 in the second, 4 in the third, 8 in the fourth, and so on, he gave answers for the fourtheenth (8,192), for the eighteenth (131,072), and the twenty-fourth (8,388,608) instantaneously, and he gave the answer for the forty-eighth box (140,737,488,355,328) in six seconds," and that he "also gave the total in all 64 boxes correctly (18,446,734,073,709,551,615) in forty-five seconds."
  • A blind boy named Fleury was of such low intelligence he had to be institutionalized, but he could calculate 2 to the 30th power (1,073,741,824) in only 40 seconds, and could calculate the cube root of 465,484,375 (which is 775) in 13 seconds.
  • A pair of twins named George and Charles (born three months prematurely) could do calendar calculations with blazing speed. We read this: "Give them a date and they can give you day of the week over a span of 80,000 years, 40,000 backward or 40,000 forward." Also, we read that if you "ask them to name in which years in the next 200 (or any 200) Easter will fall on March 23," then they "will name those years with lightning rapidity, faster than a computer and just as accurately." This seems all the more impressive when you consider that the rules for when Easter will occur in a particular year are quite complicated. In the same chapter we read about other people who could do calendar calculations with blazing speed.
  • A subject ND was tested using "randomly selected calendars from the last 300 years with the help of a computer program," being asked  the "weekdays of randomly selected calendar dates."  He "correctly answered all questions with a mean delay of 1 s [one second]" which means he instantly answered correctly all the questions such as which day of the week was October 23, 1745. 

Treffert's book is filled with cases like these: cases of people who think way, way faster than should be possible with a brain such as humans have, and cases of people who remember way, way better than should be possible with brains such as ours, having none of the main characteristics of manufactured information storage systems such as computers. Many of these people had severe brain damage. But Treffert failed to put two and two together in this matter. On page 207-208 he asks some questions that should raise doubts about claims of neural memory storage. We read this set of questions about human memory:

"Is storage electrical? If so, then why aren't memories permanently destroyed during an epileptical seizure, which is truly an electrical storm in the brain -- as can be witnessed by watching an EEG during a seizure? Or, if storage is electrical, why aren't memories permanently affected when a patient receives electroconvulsive therapy (ECT), during which time an electrical current is passed through the brain ? If storage is electromagnetic in the same manner that storage of 'memories' on tape or storage of data on a computer is, then why isn't memory permanently affected by a nuclear magnetic resonance (NMR) brain scan, during which the brain is subjected to tremendous magnetic fields? Try that with some tapes or disks. If storage is an actual physical storage, like grooves on a phonograph disk, why isn't there some clear evidence of that process in microscopic examination of the brain?" 

I wish this quote could be posted on the wall of every neuroscientist. Alas, Treffert failed to ponder the implications of his own questions. On page 208, he says "These, and many more, are questions I guess we will need to leave for the future"; and then in the rest of the book he just keeps spouting conventional neuroscience dogmas about memories storing brains. Treffert should have concluded from his own questions and the case histories he reported (often involving heavily brain-damaged people with blazing fast minds or exceptionally powerful memories) that the brain is not the source of human minds, and not the storage place of human memories. 

To find cases of human mental performance that should be utterly impossible given the physical limitations of the brain, you do not need to delve into the literature documenting paranormal phenomena (although doing that will yield a huge number of such cases). You can merely search for the most remarkable cases of mental performance that are not disputed. Besides searching for cases of exceptionally fast thinking, you can search for cases of exceptional memory. Below is a quote from page 53 of the book The Mind and Beyond published by Time-Life Books:

"As reported in the 1990 edition of the Guinness Book of World Records, in 1967, one Mehmed Ali Halici of Turkey recited from memory 6,666 verses of the Koran in six hours. And in 1989, Englishman Tony Power memorized in correct order a random sequence of thirteen packs of shuffled playing cards – 676 cards in all – after looking at them only once. But the world record for a single eidetic memory feat may be held by Bhandanta Vicitasara of Rangoon, Burma who in 1974 correctly recited from memory 16,000 pages of Buddhist canonical texts."

Mehmed Ali Halici's recitation rate was so fast it was faster than a normal person speaking as fast as he can. This was six hours of memory recall at a rate that was basically instantaneous. A hundredth of such speed would have been impossible given a brain with all the speed limits mentioned above.  The fast recall of a single page of memorized text is not explainable under the dogmas of neuroscientists, who have no credible explanation as to how a brain could store a single page of text, no explanation of how memories could be preserved for years, and no explanation of how memorized information could be instantly retrieved in brains lacking any of the things that make fast recall possible (such as addressing, sorting and indexes). Not one single word has ever been found stored in brain tissue by examining brain tissue. 

There is no neuroscientist in the world who can give a detailed credible explanation of how a human brain could even store the mere phrase "my dog has fleas," giving a precise worked example showing how each one of those characters could be stored in a brain. When neuroscientists talk about memories being stored by "alteration in connection patterns" or "synapse strengthening," they are engaging in mere hand waving. As Treffert asked, "If storage is an actual physical storage, like grooves on a phonograph disk, why isn't there some clear evidence of that process in microscopic examination of the brain?" The very likely answer is: because brains do not store information humans memorize. 

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