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

meningo-encephalitis."

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

hospital."

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 wikiepdia.org article says that such a term refers to "impairments of nerve, spinal 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? 

More Evidence of High Mental Function Despite Large Brain Damage

In another post on this site, I presented many cases showing that people can have very high mental function despite massive brain damage. In this post I will look some additional cases showing such a thing.

First let's look at some results concerning strokes. This article in US News and World Report says, "It’s important to recognize that strokes do not cause a drop in overall intelligence.” This paper refers to “the generally minor effect of stroke on IQ” in children. 

A paper here noted a case of retrograde amnesia (failure to remember previous memories) that went across many domains of knowledge. But the paper noted, "Across all domains tested, LSJ showed losses of knowledge at a level of breadth and depth never before documented in retrograde amnesia."  Note the "never before documented."  If brains are storing our memories, you would think that many such cases would have been previously documented, because of all the people suffering brain jury from disease, cancer, or car accidents. 

The recently published scientific paper here is entitled “A Lesion-Proof Brain? Multidimensional Sensorimotor, Cognitive, and Socio-Affective Preservation Despite Extensive Damage in a Stroke Patient.” Here is an astonishing report from the paper's abstract, describing a patient who seems mentally undamaged despite massive brain injury:

At age 43, patient CG sustained a cerebral hemorrhage and a few months later, she suffered a second (ischemic) stroke. As a result, she exhibited extensive damage of the right hemisphere (including frontal, temporal, parietal, and occipital regions), left Sylvian and striatal areas, bilateral portions of the insula and the amygdala, and the splenium. However, against all probability, she was unimpaired across a host of cognitive domains, including executive functions, attention, memory, language, sensory perception (e.g., taste recognition and intensity discrimination), emotional processing (e.g., experiencing of positive and negative emotions), and social cognition skills (prosody recognition, theory of mind, facial emotion recognition, and emotional evaluation).

Below is the paper's startling discussion of the very well-preserved memory in this patient who had suffered heavy brain damage from two strokes:

Even more striking are her mnemonic skills: her procedural and semantic knowledge is fully preserved, as shown in her smooth execution of various action routines (e.g., handling her cell phone, tying her shoe laces) and her intact naming and classification skills (e.g., she could flawlessly denominate all the objects she had thematically organized in different sections of her purse); furthermore, her declarative memory is extremely detailed for events which happened weeks, months, and even years ago. She could describe scenes from her childhood and adolescence, she meticulously narrated episodes occurring immediately before and after her strokes, she remembered the names, specialties, and suggestions of all her doctors, and she could recount details of dozens of books she had read throughout her life.

We know that Alzheimer’s disease can cause an inability to recall memories, although whether the memories are actually lost is debatable. What is remarkable is the fact that a large fraction of the brain can be ruined by Alzheimer’s disease before a patient can become noticeably poor at remembering things. Here is a quote from an expert on the disease:

One of the big challenges we face with Alzheimer's is that brain cell destruction begins years or even decades before symptoms emerge. A person whose disease process starts at age 50 might have memory loss at 75, but by the time we see the signs, the patient has lost 40 to 50 percent of their brain cells.

The same very astonishing thing is said in this article, which quotes an expert saying the following:

In Alzheimer’s, brain cells start to die 10, 15, or 20 years before symptoms appear. By the time we observe memory lapses, 40 percent to 50 percent of brain cells are gone, and it’s too late to make a difference.

These statements are astonishing. If our memories are all stored in our brains, why would you have to lose 40 to 50 percent of your brain cells before people started noticing your memory loss? Again, this suggests merely a low correlation between brain health and mental function.

On this page we have the amazing story of an MIT student who helped doctors find a baseball-sized tumor in his brain. Doctors performed surgery and removed the tumor. Later, the student gave a presentation to cancer researchers. A video of the presentation is included on that page. Amazingly, the young man seems to show no sign whatsoever of a damaged mind. He walks and talks normally, and seems to have slick presentation skills sufficient to land him a job as a host on a morning TV show. The page tells us that this young man is now pursuing a PhD in mechanical engineering. In the presentation, the young man tells us that the doctors removed about 12 billion neurons in his brain.

The paper here studied memory effects in 63 patients who had undergone surgery for brain cancer, in addition to other patients who had undergone both brain surgery and radiotherapy. 91% of these 63 patients experienced “no deterioration” in immediate recall; 80% experienced “no deterioration” in delayed recall; and 77% experienced “no deterioration” in recognition. This is a relatively low correlation between brain damage and memory, particularly considering that about half of the patients had 2 or more brain metastases (areas in which the cancer was growing).

Figure 8 of this paper gives us a graph that compares verbal IQ with brain tumor size in a variety of brain cancer patients. Under materialist assumptions, we would expect that there should be a strong inverse correlation between something like verbal IQ and the size of a brain tumor; the bigger the brain tumor, the lower your verbal intelligence should be. But what we see is only a low correlation – a correlation of only .28. High correlations have values like .75 or .85. Astonishingly, the person with the highest verbal intelligence had the biggest brain tumor, and the person with the second highest intelligence also has a very large brain tumor. We can easily account for the slightly-below-average IQ scores of brain tumor patients 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.

It is part of the dubious folklore of neuroscientists that the prefrontal cortex is some center of higher reasoning. But the scientific paper here tells us that patients with prefrontal damage "often have a remarkable absence of intellectual impairment, as measured by conventional IQ tests." The authors of the scientific tried an alternate approach, using a test of so-called "fluid" intelligence on 80 patients with prefrontal damage.  They concluded "our findings do not support a connection between fluid intelligence and the frontal lobes." Table 7 of this study reveals that the average intelligence of the 80 patients with prefrontal brain damage was 99.5 – only a tiny bit lower than the average IQ of 100. Two of the brain-damage patients had genius IQs of higher than 140. This is not a result consistent with the claim that brains make minds. 

In a similar vein, the paper here tested IQ for 156 Vietnam veterans who had undergone frontal lobe brain injury during combat. If you do the math using Figure 5 in this paper, you get an average IQ of 98 for these 156 brain-damaged veterans, only two points lower than average. You could plausibly explain that 2 point difference purely by assuming that those who got injured had a very slightly lower average intelligence before they were injured. 

It also should be remembered that brain-damaged patients taking standard IQ tests may have higher intelligence than the test score suggests.  A standard IQ test requires visual perception skill (to read the test book) and finger coordination (to fill in the right answers using a pencil). Brain damage might cause reduced finger coordination and reduced visual perception unrelated to intelligence; and such things might cause a subject to do below-average on a standard IQ test even if his intelligence is normal.  And if you're a patient with a terminal brain tumor, you may have psychological distress and head pain that may cause a reduced score in your paper-and-pencil IQ test. 

There is a type of surgery called a hemispherectomy, and is sometimes performed on children experiencing severe seizures. The operation involves surgically removing half of the brain. The surgery is described in a Scientific American article entitled Strange but True: When Half a Brain Is Better than a Whole One. The article states: “Unbelievably, the surgery has no apparent effect on personality or memory.”

According to this link, 70% of the children who had half of their brains removed were able to speak well, and 42% older than 6 were able to read well. Given that only about 60% of the American population can read well, this 42% figure is amazingly high.  A paper here tracks the before and after IQ scores of 12 children who had a hemispherectomy operation to remove half of their brain (usually to treat severe seizures). Half of the children had higher IQ scores when tested two years after half of their brains were removed, compared to their scores before the operation. 

When we consider sudden traumatic injury to the brain, we also find some cases where the correlation between brain health and mental function seems to be merely a low correlation. One astonishing case is that of Gabby Giffords, a US congress representative who was shot at point-blank range in the back of the head. Not only did she live, but she has recovered to a remarkable degree, to the point of being able to bike, and speak clearly (although in shorter sentences). A similar case was the famous case of Phineas Gage, a nineteenth century railroad worker who had a thick iron railroad spike accidentally drive through his skull, piercing his frontal lobes. A physician reported after examining Gage that he was “quite recovered in his faculties of body and mind.” Gage seems to have had some personality changes later, which may or may not have been related to his injury. But such changes are trivial compared to what we would have expected from such an injury under materialistic assumptions about the brain. An expert on Gage has stated that the personality change “did not last much longer than about two to three years,” but Gage lived for 12 years after the accident.

A Lancet study involving nearly three million people found only a small relation between traumatic brain injury and the risk of dementia. Those with severe traumatic brain injury were only 35 percent more likely to develop dementia. Since the lifetime risk of dementia is less than 20 percent, this means that 70 percent or more of people who suffer traumatic brain injury do not get dementia.  With a correlation this small, we can't even be sure whether there is a causal relation. By comparison, you are 2300% more likely to develop lung cancer if you smoke. 

It has been estimated that the cerebellum contains between 50 percent and 80 percent of the neurons in the brain.  In China a woman was discovered to have no cerebellum at all. But her defects were relatively minor, such as slurred speech, a need to use something like a cane to walk, and a lack of athletic ability. The woman could understand speech well enough. According to a scientific paper describing her, she had merely "mild mental impairment." This is yet another case showing only a small correlation between brain health and intellectual ability. 

In the paper "Subtotal agenesis of the cerebellum in an adult," we read this: 

"We describe a 58-year-old asymptomatic woman with subtotal developmental absence of the cerebellum. MRI evaluation showed minute remnants of cerebellar tissue corresponding to the anterior quadrangular lobules."

Note the word "asymptomatic." This is a case of a woman who suffered no symptoms despite not having a cerebellum, the part of the brain where most neurons exist. Similarly, in the 1950 link here, on the far right, we read of a man who "was born without a cerebellum and seemed to suffer no noticeable disadvantage from the fact."

These cases all tell us the same thing: that there is merely a low correlation between brain health and mental function, and that people can often have very high mental function even when their brains are greatly damaged. As a scientific paper says, “There does not appear to be a direct relationship between the degree of brain pathology or brain damage and the clinical manifestation of that damage.”

Such cases are not at all compatible with the conventional thinking of neuroscientists that the human mind is merely the product of the brain. But such cases are compatible with the assumption that the human mind is mainly the product of some mysterious reality beyond our understanding: a soul or some cosmic consciousness infrastructure much greater than a human body.

But a mainstream might argue that we should believe our memories are all stored in our brains, on the grounds that brains are active when we are remembering, and very heavy brain damage may be associated with memory loss. The visual below illustrates why such

reasoning is not convincing.

Below is a very notable case of the almost complete destruction of a brain by a brain tumor, but with a high preservation of mental function. It comes from page 71 of the document here (and the newspaper story here repeats the same details).