Sunday, May 26, 2019

More Evidence That Neuron Loss Has Little Effect on Cognition

The claim that the human mind is produced by the human brain has always been a speech custom of scientists, rather than an idea that has been established by observations. No one has any idea of how neurons might produce human mental phenomena such as abstract thinking and imagination. Contrary to the predictions of the idea that brains make minds, there are a huge number of case histories showing that human minds suffer surprisingly little damage when massive brain injury or loss of brain tissue occurs. I have published three long posts (here, here, and here) citing many such cases, including cases of epilepsy patients who had little loss of intelligence or memory after they lost half of their brains in a hemispherectomy operation to stop seizures, and patients who had above-average or near-average intelligence despite loss of most of their brains. I will now cite some additional cases of minds little affected by huge brain damage, cases I have not mentioned before.

The cases I will discuss are mainly referred to as abscesses. An abscess is an area of the brain that has experienced necrosis (cell death) because of infection or injury. A medical source refers to an abscess as “an area of necrosis,” and another medical source defines necrosis as “the death of body tissue.” If you do a Google image search for “abscess,” you will see that a brain abscess generally appears as a dark patch in a brain scan. It is roughly correct to refer to an abscess as a brain hole, although the hole is a filled hole, filled mainly with pus, dead cells and fluid. An image of an abscess is below.

The two cases in the quoted paragraph below are reported on page 78 of the book From the Unconscious to the Conscious by physician Gustave Geley. You can read the book here. Astonishingly, Geley refers in the first sentence to a man who lived a year “without any mental disturbance” despite a great big brain abscess that left him with “a brain reduced to pulp”:

"M. Edmond Perrier brought before the French Academy of Sciences at the session of December 22nd, 1913, the case observed by Dr R. Robinson; of a man who lived a year, nearly without pain, and without any mental disturbance, with a brain reduced to pulp by a huge purulent abscess. In July, 1914, Dr Hallopeau reported to the Surgical Society an operation at the Necker Hospital, the patient being a young girl who had fallen out of a carriage on the Metropolitan Railway. After trephining, it was observed that a considerable portion of cerebral substance had been reduced literally to pulp. The wound was cleansed, drained, and closed, and the patient completely recovered."

The following report (quite contrary to current dogmas about brains) was made in a Paris newspaper of a session of the Academy of Sciences on March 24, 1917, and is quoted by Geley on page 79 of his book:

"He mentions that his first patient, the soldier Louis R , to-day a gardener near Paris, in spite of the loss of a very large part of his left cerebral hemisphere (cortex, white substance, central nuclei, etc.), continues to develop intellectually as a normal subject,in despite of the lesions and the removal of convolutions considered as the seat of essential functions. From this typical case, and nine analogous cases by the same operator, known to the Academy, Dr Guepin says that it may now safely be concluded:
(i). That the partial amputation of the brain in man is possible, relatively easy, and saves certain wounded men whom received theory would regard
as condemned to certain death, or to incurable infirmities.
(2). That these patients seem not in any way
to feel the loss of such a cerebral region."

On page 80 of Geley's book we have the following astonishing case involving an abscess in the brain. We are told the boy had “full use of his intellectual faculties” despite a huge brain abscess and a detachment “which amounted to real decapitation”:

"The first case refers to a boy of 12 to 14 years
of age, who died in full use of his intellectual faculties
although the encephalic mass was completely detached
from the bulb, in a condition which amounted to real
decapitation. What must have been the stupefaction
of the operators at the autopsy, when, on opening
the cranial cavity, they found the meninges heavily
charged with blood, and a large abscess involving
nearly the whole cerebellum, part of the brain and
the protuberance. Nevertheless the patient, shortly
before, was known to have been actively thinking.
They must necessarily have wondered how this could
possibly have come about. The boy complained of
violent headache, his temperature was not below
39 °C. (io2.2°F.) ; the only marked symptoms
being dilatation of the pupils, intolerance of light,
and great cutaneous hyperesthesia. Diagnosed as

On page 81 we learn of the following equally astonishing case involving a patient who “thought as do other men” despite having three large brain abscesses, each as large as a tangerine:

"A third case, coming from the same clinic, is
that of a young agricultural labourer, 18 years of
age. The post mortem revealed three communicating
abscesses, each as large as a tangerine orange,
occupying the posterior portion of both cerebral
hemispheres, and part of the cerebellum. In spite
of these the patient thought as do other men, so
much so that one day he asked for leave to settle
his private affairs. He died on re-entering the

These cases are quite consistent with more modern cases reported in recent decades, cases in which we also see very little loss of function despite massive brain damage. A 2015 scientific paper looked at 162 cases of surgery to treat brain abscess, in which parts of the brain undergo the cell death known as necrosis, often being replaced with a yellowish pus. The article contains quite a few photos of people with holes in their brains caused by the abscesses, holes in their brains of various sizes. The paper says that “complete resolution of abscess with complete recovery of preoperative neuro-deficit was seen in 80.86%” of the patients, and that only about 6% of the patients suffered a major functional deficit, even though 22% of the patients had multiple brain abscesses, and 30% of the abscesses occurred in the frontal lobe (claimed to be the center of higher thought). 

Interestingly, the long review article on 162 brain abscesses treated by brain surgery make no mention at all of amnesia or any memory effects, other than to tell us that “there was short-term memory loss in 5 cases.” If our memories really are stored in our brain, how come none of these 162 cases of brain abscesses seem to have shown an effect at all on permanent memories?

Similarly, a scientific paper on 100 brain abscess cases (in which one fourth of the patients had multiple brain abscesses) makes no mention of any specific memory effect or thinking effect. It tells us that most of the patients had “neurological focal deficits,” but that's a vague term that doesn't tell us whether intellect or memory was affected. (A article says that such a term refers to "impairments of nervespinal cord, or brain function that affects a specific region of the body, e.g. weakness in the left arm, the right leg, paresis, or plegia.")   The paper tells us that after treatment “80 (83.3%) were cured, eight (8.3%) died (five of them were in coma at admission), seven had a relapse of the abscess,” without mentioning any permanent loss of memory or mental function in anyone.

Another paper discusses thousands of cases of brain abscesses, without mentioning any specific thinking effects or memory effects.  Another paper refers to 49 brain abscess patients, and tells us that "the frontal lobe was the most common site," referring to the place that is claimed to be a "seat of thought" in the brain. But rather than mentioning any great intellectual damage caused by these brain holes, the paper says that 39 of the patients “recovered fully or had minimal incapacity,” and that five died.

In 1994 Simon Lewis was in his car when it was struck by a van driving at 75 miles per hour. The crash killed Lewis' wife, and “destroyed a third of his right hemisphere” according to this press account. Lewis remained in coma for 31 days, and then awoke. Now, many years later, according to the press account, “he actually has an IQ as high as the one he had before the crash.” In 1997, according to the press account, Lewis had an IQ of 151, which is 50% higher than the average IQ of 100. How could someone be so smart with such heavy brain damage, if our brains are really the source of our minds?  

These cases are merely a small part of the evidence that large brain damage very often produces only very small effects on mind and memory. The three posts here and here and here give many other cases along the same lines, some suggesting even more dramatically that a large fraction of the brain (often as much as 50% and sometimes as much as 80%) can be lost or removed without causing much memory loss or preventing fairly normal mental function and memory function. The facts of neuroscience do not match the dogmas of neuroscientists, who make unwarranted “brains store memories” and “brains make minds” claims that are in conflict with facts such as medical case histories of high brain damage with little mind damage, the short lifetimes of the proteins that make up synapses, the low signal transmission reliability of noisy synapses, and the failure of scientists to detect any sign of encoded information (other than DNA gene information) in brains.

A study published in December, 2018 attempted to draw a link between neural parameters (such as cortical thickness and neuron size) and intelligence.  The study failed to present any convincing evidence for such a thing.  The study involved only a few dozen subjects, and the neurons analyzed were a few dozen neurons arbitrarily chosen.  Given the freedom to make 100 comparisons chosen as you wish from a mass of data, you can produce weak correlations suggesting whatever hypothesis you favor. An example of the very weak correlations in the paper is Figure 2D in the paper, which attempts to show a correlation between cortical thickness and IQ. But if you click on the "see more" link, you will see the correlation measure (R squared) is only .15, which is basically no real evidence of a correlation (as explained here), particularly in a sample size so small.  When there is good evidence for a correlation, you have an R squared such as .5 or .7.  Similarly weak correlations (with an R squared average of only .19) are presented in 4 other graphs. 

But there is in the paper evidence that conflicts with the whole idea that brains produce minds. That evidence is found in Table 1, which lists the IQ scores of people with serious brain tumors requiring surgery.  The IQ tests were taken shortly before the surgery, and tell us about the intelligence of the people after their brains were devastated by tumors.   Here are the IQ scores of the people with brain tumors: 88, 119, 88, 107, 125, 84, 110, 97, 77, 83, 102, 99, 82, and 114. This gives us an average of 98, which is only very slightly smaller than the average IQ of 100. The figures are not what we would expect from the claim that the brain produces intelligence, and the figures are consistent with the hypothesis that brain tumors do not have a large effect on intelligence.  Similar results are found in this paper, in which 49 brain tumor patients were found (in pre-surgical IQ tests) to have an average IQ of 95.4.  We can easily account for the slightly-below-average scores by simply assuming that in these brain tumor patients there would often be visual perception problems, muscular coordination problems, psychological distress, and head pain problems, which would tend to slightly decrease scores in pencil-and-paper IQ tests, without there actually being a decrease in intelligence.  

Discussing hemispherectomy operations in which half of a brain is removed to stop seizures, the paper here states, "Others, (Ogden, 1988; Riva & Gazzaniga, 1986; Vargha-Khadem et al., 1997a; Verity, 1982) have reported excellent, even normal linguistic abilities after hemispherectomy of either side" of the brain. An interesting scientific paper is entitled, "When only the right hemisphere is left: Studies in language and communication." The study gives us an in-depth analysis of a subject named BL who had half of his brain removed (the left half) in a hemispherectomy operation to reduce seizures.  The paper tells us that BL is "above normal intelligence" and that he graduated from college with a double major in business and sociology.  In a battery of tests of memory and language, the subject showed normal results, with only slight, subtle defecits. He scored above-average on a few memory-related tests, such as the Boston Naming Test and the Famous Names and Faces test.  We are told, "Regarding speech, language, and communicative function, BL's performance appears grossly normal in pronunciation, grammar, semantics, and usage." 

A study such as this helps to debunk dogmas such as the dogma that the brain is the source of our minds.  You can read about many similar cases by following the links above.  Referring to patients who had half of their brains removed in hemispherectomy operations, the paper states, "The numerous observations on cognitively intact persons hemispherectomized in childhood bring to mind the report of Lorber (1983) on hydrocephalic adults, whose brains are constituted of only a thin layer of cerebral tissue, and yet who enjoy normal or superior motor and cognitive abilities." Talking about the small effect of hemispherectomy operations in which half of a brain is removed, a doctor states, "When you take out half of their brain in one sitting it’s as if they weren’t touched." When will our neuroscientists start putting two and two together to reach the conclusion that is taught by such observational facts? 

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