Showing posts with label loss of left half of brain. Show all posts
Showing posts with label loss of left half of brain. Show all posts

Thursday, September 3, 2026

They Had Good Minds After Losing the Left Half of Their Brains

Although neuroscientists are brain specialists, very many neuroscientists are not very deep and broad scholars of the topic of human brains. A typical neuroscientist may be able to tell you in very great detail about some narrow facet of human brains, and may be able to tell you in the greatest detail about how to use some machine that is used to study brains. But the same neuroscientist may have failed to properly study the topic of human brains in a way that involves learning about every relevant thing you could about human brains. Ask that neuroscientist to tell you what happens when you remove half of a human brain, and you may get an answer that is wrong. Ask that neuroscientist to tell you how reliably chemical synapses transmit nerve signals (action potentials), and you may get an answer that is wrong. Ask that neuroscientist to tell you how quickly a brain electrically shuts down when the heart stops (reaching a state called asystole), and you may get an answer that is wrong. 

Part of the job of properly studying brains is to study very thoroughly all of the most impressive cases of high mental performance despite very high brain damage. Relatively few neuroscientists show signs of having studied such a topic. In order to properly study such a topic, you must study unusual medical case histories.  Very many of the most important and relevant medical case histories are recorded in books, newspapers and magazines. But can you ever recall reading of a neuroscientist searching newspapers for unusual case histories in neuroscience? I can never recall reading of such activity by a neuroscientist. 

Luckily there are some web sites that contain very many of the most relevant examples of such medical case histories that are relevant to the question of whether the human mind is the source of the mind and whether the human mind is the storage place of human memories. One of those sites is the very site you are reading.  In my series of posts labeled "High Mental Function Despite Large Brain Damage," which you can read here, I describe many of the most important case histories that are  relevant to the question of whether the human brain is the source of the mind (keep pressing Older Posts at the bottom right to read the whole series). Now let me provide another such case, one I learned about from searching old newspaper articles for a use of the phrase "half a brain." The 1976 case is one that you can read about using the link here. Below are some excerpts from the newspaper article.

half a brain and superior intelligence

We read of a young man named Bruce Lipstadt who had a hemispherectomy operation when he was five years old, an operation that removed the left half of his brain.  Operations of that type are only done when someone is being plagued by very severe seizures, and the seizures cannot be controlled by medication.  The operation was done because as a young boy Bruce was suffering from 10 to 12 seizures a day. 

We are told that despite having the left half of his brain surgically removed, Bruce can ride a bike, swim and play sports. We are told that Bruce got an A grade (the best grade) in a course on statistics at a university. We are told Bruce's speech is normal. We are told that "although not a genius, Bruce has superior intelligence." We are told that Bruce works as a traffic controller, and that next spring he will get a degree in sociology from a university. 

The 1976 newspaper article here gives us some more details on Bruce Lipstadt. We read that his IQ tests showed his verbal IQ to be 126, well above the average IQ of 100. We read this:

A verbal IQ of 126 in a subject who had the left half of his brain removed is a result that would seem to "make mincemeat" out of claims that the brain is the source of the human mind. One of the accounts above mentions an authority named Sugar. The Bruce Lipstadt case seems to be the same one mentioned in the scientific paper here co-authored by Oscar Sugar MD, one entitled "Development of above normal language and intelligence 21 years after left hemispherectomy."

The newspaper article here tells of a film about a man who had the left half of his brain removed, but who (five months after the operation) could still "sing, distinguish colors, and pass simple tests of reading, writing and arithmetic."


At the 2:59 mark in the Youtube.com video here, we get the table below, which shows some impressive intellectual achievements in patients who underwent a hemispherectomy operation to remove half of their brains:

We have some stunning results. All of these people with half a brain had some college studies. Two had achieved a two-year Associate's Degree. One had achieved a Master's Degree. The top row tells whether the left or the right half of the brain was removed.  The two rightmost columns give details for people who had the left half of their brain removed, both of which had some college studies, and both of which were employed. 

At the 5:03 mark in the video, we have the chart below. It shows the IQ of 7 subjects who had a hemispherectomy operation to remove half of their brains. The dots in yellow are people who had left half of the brain removed. Each column represents a particular type of IQ. The first column is full IQ. The second column is verbal IQ. The third column is performance IQ, something that does tests involving non-verbal tasks and motor tasks, with speed of completion affecting the score. We see that one of the subjects who had the left half of his brain removed had above-average verbal IQ. 


At the 8:07 mark in the video, we have a chart showing that one of the left hemispherectomy patients (who had the left half of the brain removed) had a way-above-average 130 score on reading comprehension. 

At the link here, you can read the very interesting paper "AN ENORMOUS CEREBRAL TUMOUR" by William E. Conroy M.D. We read of a patient F. H. who was observed in 1889. The patient had an operation to remove the tumor, but died soon thereafter. 

On page 179 we read that an autopsy was performed, and that after the tumor was removed, the left half of the brain was all but gone, being only the size of the palm of a hand:

On page 180 we read that this "enormous" tumor in the left half of the brain produced almost no mental effects. We read that the boy was "intelligent" and "expressed himself well" and "read much with enjoyment" until his eyesight failed. We read that the mental faculties were "not seriously impaired."  We read this:

good mind without left half of brain

On page 16 of an 1899 book J. Sanderson Christison, M.D.  states this: "And when we find that individuals have filled the business and social functions of life in the ordinary way, who were either destitute of a corpus callosum (see page 65) or had but little more than half a brain (see page 62), it is evident that external features are not necessarily of fundamental significance." 

On page 47 Dr. Christison says this:

"Dr. E. W. Taylor reports a man, 36 years of age, with extensive destruction of the left frontal lobe of the brain, and yet, says Dr. Taylor: 'When I last saw him the whole impression was that of a clear-headed vigorous man of exceptional intellect, but neurasthenic. A few days before his death he was filling a responsible position, and making decisions of importance with accuracy and judgment.' "

On pages 58-59 Christison says this:

"Dr. Charles Phelps reports a man who died at the age of 25 years with a large abscess in the middle area of the left cerebral hemisphere, while a large proportion of both hemispheres was either softened or invaded with punctate hemorrhages. Yet Dr. Phelps reports that this man 'had absolute integrity of all his mental faculties and special senses without either having aberration or decadence, and was cheerful and slept well.' "

On the same page 59 Christison says this:

"Drs. J. J. Putnam and M. H. Richardson report a business-man, 30 years of age, whose entire left cerebral hemisphere (except the occipital lobe and the lower portions of the frontal and temporal lobes) was occupied by a diseased growth, 'which everywhere compressed the adjoining brain tissues and to a great extent destroyed them,'  and yet in this man 'no notable mental changes were observable.'  'His mind was clear and he read and understood with pleasure, and enjoyed the society of his family and friends,' and although 'he dragged his right leg he walked well, going to church and back half a mile off, and he drove his horse to town eight miles away, four days before his death.' "

On page 61 Dr. Christison says this:

"Dr. W. B. Haddon reports a man, 21 years of age, with an enormous tumor occupying the left cerebral hemisphere, and severely compressing adjacent structures. Yet, although he occasionally had an epileptic fit and stammered slightly from childhood, he had no paralysis. He was somewhat opinionated, but evinced no moral perversion. At the time of his death (in a fit) he was a clerk in the Steward's office of St. Thomas' Hospital, London, and a few days later he would have entered the government examination for a second grade certificate in perspective and drawing, branches in which he was pronounced by experts to be exceptionally proficient."

On page 62 Dr. Christison says this:

 "Andral reports a man who died at the age of 28 years with the whole of his right cerebral hemisphere so completely atrophied that its covering membrane (pia mater) formed a cyst in which there was not a trace of brain tissue. The floor of the cyst was formed by the optic thalamus, the corpus striatum, and the parts on a level with these two bodies. Yet, says Andral, this man  'had received a good education, had a good memory, and exhibited as much intelligence as most men' (19)."

Sunday, November 23, 2025

More Old Newspaper Stories Relevant to Whether Brains Make Minds

The Chronicling America web site allows you to make a full-text search of many decades of American newspapers. Below are some interesting clips from old newspaper articles, all having some relevance to whether the human brain makes the human mind.  

The news account below is from 1957:

right hemispherectomy

You can read the report here:


The account below is from the nineteenth century. We hear of a man who apparently did not suffer intellectual damage from losing half of his brain. 

small effect of brain injury

You can read the 1876 account here:


The newspaper account below is from 1898:

good minds and bad brains


You can read the story here:


Using an OCR feature of the page above, I get this quotation of its middle part:

"In instances in which it was discovered after death that the connecting bridge between the hemispheres
was entirely wanting, neither derangement in intellect was observed, nor any other abnormality of life in the way of movement or sensation. Thus, in the notable case of Bichat, one of the foremost anatomists of his day, one lobe of his brain was found markedly smaller than the other. He was, in fact, deficient in one-half of his brain, and yet his mental and physical life was in its way notably of a high order. In another case, reported by Cruveilhier, a man died in the hospital at the age of 42 years from heart disease. He exhibited no lack of intelligence, yet after his death it was discovered that his left brain was practically destroyed and replaced by a watery substance. Another case, reported by Andral, was of a man who died at the age of 2S. He had suffered from a fall when three years old, and as a result was paralyzed on his left side. The right half of his brain had practically disappeared, so that the parts below this half constituted the floor for an empty space. Andral says of this
man that he 'had received a good education, and had profited by it; he had a good. memory; his speech was free and easy; his intelligence was such as we should expect to find in an ordinary man.' "

Below is a news story from 1938. We read of a girl "with half a brain" who carried on in a "remarkably satisfactory manner":

good mind with half a brain

You can read the news story here:


We have below a report that is not at all what we would expect if the brain produces the mind.  The report is of patients who underwent surgeries that surgically severed the two halves of their brain. But instead of this producing a drastically different mind, or two minds, we have apparently minimal effects:

split brain operation

You can read the story using this link:


The 1905 newspaper account below tells us of a man who seemed to have suffered little mental damage from losing most of his brain:


You can read the account here:


Here is a news account from 1987 telling us of a big improvement in reading ability after half of a girl's brain was removed. 


little damage from loss of half of brain

You can read the full story here:


A fact contrary to all claims that brains make minds is the fact that very severe pain can be completely cancelled by the use of hypnosis. Below is a news story documenting the effect. 

hypnotism preventing pain during surgery

On pages 27-28 of a book by Dr. James Esdaile he lists a host of dramatic painless surgeries he performed without using anesthesia, but only hypnosis on patients. The list includes about 20 amputations, and 200 removals of scrotal tumors ranging from 10 pounds in weight to more than 100 pounds in weight. Another book on this topic by Esdaile can be read here. 

In the following quote from a nineteenth century work, we learn of a great irony: that physicians took up a chemical method of anesthesia, one which would often kill people, rather than using hypnotic methods of anesthesia that were proving very safe and effective:

"In Dr. Brown Sequard's lectures upon 'Nervous Force,' delivered in Boston in 1874, he speaks of this form of anaesthesia as follows : 

'As regards the power of producing anaesthesia, it seems to me unfortunate that the discovery of ether was made just when it was. It was, as you well know, in 1846 or 1847 that the use of ether as an anaesthetic was begun. It started from this city (Boston). At that time in England, Dr. Forbes was trying to show from facts observed in England, and especially in India, from the practice of Dr. Esdaile, that something which was called Mesmerism, but which, after all, was nothing but a peculiar state of somnambulism induced in patients, gave to them the idea that they were deprived of feeling ; so that they were in reality under the influence of their imagination, and operations were performed that were quite painless. I say that it was a pity that ether was introduced just then, as it prevented the progress of our knowledge as to this method of producing anaesthesia. My friend Dr. Broca took it up in 1857-8 and pushed it very far; and for a time it was the fashion in Paris to have amputations performed after having been anaesthetized by the influence of Braidism or Hypnotism. A great many operations were performed in that way that were quite painless. But it was a process that was long and tedious, and surgeons were in a hurry and gave it up. I regret it very much, as there has never been a case of death from that method of producing anesthesia, while you well know that a great many cases of death have been produced by other methods.' "

Thursday, July 3, 2025

They Lost Huge Parts of Their Brains, But Their Knowledge and Recollection Were Preserved

 When people think of neuroscience experiments, they typically think of experiments done with mice. If they think of neuroscience experiments involving humans, they may think of some experiment involving the use of some drug, with a test to see whether the drug affects mental performance.  Such experiments are formally designed with things such as a set of test subjects, a set of control subjects that do not have any intervention occurring to them, and so forth. 

But some of the most important experiments in neuroscience have been those that were not part of some procedure declared as an experiment. The experiments have occurred when some large part of a human brain was removed in surgery. Whenever such an operation is done, it is an important experiment that tests the credibility of the claims that neuroscientists so often make. 

Neuroscientists are always claiming that learning occurs through some brain action, that memories are stored in brains, and that recall of a memory occurs by some action of the brain. Neuroscientists senselessly keep making such claims despite their lack of any credible theory describing how any such things could be done by a brain. When a neuroscientist is asked to explain how a brain could store some newly learned knowledge, a scientist will typically engage in some vague, vacuous hand-waving which typically consists of merely reciting some little slogan or sound bite such as "synapse strengthening." There is nothing to speak of behind such a phrase, which is a mere vacuous catchphrase. When asked to explain how a human can instantly recall some knowledge, a neuroscientist will typically say nothing but the most vacuous phrase such as "stored information is recalled." 

Although not called "experiments," every time a large part of the brain is removed from a human, a very important experiment is being performed, one that sheds light on whether neuroscientist claims about memory are credible.  Under the theory that memories are stored in brains and retrieved by brains, we should expect to observe certain things:

(1) We should expect that there should be some deterioration in the ability of humans to learn new information. Such a deterioration might be small or large, depending on where brain tissue was extracted, and how brain tissue was extracted. 

(2) We should expect that there should be some loss of learned knowledge and episodic memories. Such a deterioration might be small or large, depending on where brain tissue was extracted, and how much brain tissue was extracted. 

Item (2) is often overlooked, but is obviously something to be expected under the theory that brains store memories. Imagine if someone writes down what happened to him each day, in a large book that originally consisted of blank pages. Obviously if you were rip out a large chunk of these pages and burn them, that would cause a large loss of the information that had been recorded.  It is just as obvious that if memories are stored in brains, then surgically removing some large chunk of the brain should cause some large loss of what a person had learned or the memories the person had. 

If memories are stored in the brain we should expect that a surgical removal of a large amount of brain tissue might produce effects such as these:

(1) A loss of the ability to understand some words in a person's language. Each recognition of a word that occurs when a person hears something involves the use of some learned knowledge that a person acquired sometime in his life.  

(2)  A loss of the ability to speak or write some words in a person's language. Each use of a word that occurs when a person speaks something or writes something involves the use of some learned knowledge that a person acquired sometime in his life.  

(3) A loss of the ability to recognize various types of images such as particular faces or particular words or particular symbols. Every time a person recognizes a word or a face or an object or a symbol, that involves the use of some  learned knowledge that a person acquired sometime in his life.  

(4) A loss of the ability to recall various concepts and facts that the person had learned at some time in his life. For example, a person might no longer remember what country or city he lived in, or what his name was, or what his address was. Or a person might no longer be able to explain who some famous historical figure was, someone such as Jesus or Napoleon. 

(5) A loss of episodic memories. For example, a person might no longer be able to tell you the story of his life, or tell you what type of activities he engaged in last year. 

To test whether memories are stored in brains, we can track down case histories of people who had large amounts of brain tissue surgically removed, and examine which, if any, of the effects above occurred.  Let's look at some examples of such cases. 

First, let's look at the case of Beth Usher of Storrs, Connecticut (part of the USA). Beth was mentioned in an article in the LA Times, which says she was one a group of epileptic children who had half of their brain removed, to stop very bad seizures that drugs could not stop. The article stated this:

 "How is it that 8-year-old Beth Usher of Storrs, Conn., can lose her left hemisphere, yet retain her large repertoire of knock-knock jokes? Beth’s memories survived not just the loss of brain tissue, but also the 32 days that she spent in a coma, the result of some brain stem swelling that occurred in response to the trauma of surgery. Shortly after Beth regained consciousness, her father began quizzing her about people and places from her past. Brian Usher didn’t get very far. 'Dad,' Beth interrupted, with a trace of impatience. 'I remember everything.'" 

We have here the explicit claim that Beth's memories survived the removal of the left half of her brain.  The article mentions specific things that Beth could still remember, and makes no mention of any memory or knowledge that was lost after half of her brain was removed. 

Another case is discussed here, in a book chapter of a textbook. We read of a patient E.C. who had a large brain tumor. To treat the tumor, the left half of the patient's brain was removed, in a hemispherectomy operation. We read that "the entire hemisphere was removed in one piece" on December 7, 1965. We read that "immediately following hemispherectomy" the patient had an "ability to follow simple verbal commands."  We read on page 107 that "the patient spontaneously articulated words and short phrases fairly well immediately after the operation."  

The discussion of the patient's retention of previous knowledge is rather frustrating in its lack of a comprehensive treatment. We read that this patient E.C. "gave the correct number of years when asked how long he had lived at his house." We read on page 107 that on January 26, 1966 (about six weeks after the operation) he "slowly but correctly selected four of the first six items from six pages, each with four items to choose from, before indicating he was tired" when given the Peabody picture vocabulary test. Such a test involves a tester speaking a word, and the user pointing to the correct picture in a grid of 4 pictures. 

The image below (from the paper here) shows an example of one of the pages. The word spoken by the tester is "citrus."


The result described above (4 out of 6 correct on six such pages) clearly suggests that patient E.C. retained his learned knowledge after the left half of the brain was removed. Since the test was given only six weeks after the operation, and E.C. was in a recovering state during those weeks in which he was not being schooled, we cannot explain such a result as being due to knowledge acquired during those six weeks. We also read on page 107 that on June 3, 1966 patient E.C. correctly named 85 out of 112 items on such a test. No mention is made of schooling occurring during the first six months of 1966. 

According to the paper here, "In the fifth postoperative month, E.C. showed sudden recall of whole old familiar songs (e.g., My
Country 'Tis of Thee, Home on the Range, church hymns)."

On page 109 we read of three other cases of the removal of the left half of the brain, and we read that "speech and verbal comprehension were present immediately after left hemispherectomy in all three cases." We read nothing about any loss of knowledge or episodic memories in any of these cases. 

In the scientific paper here, we have on page 248 and page 250 before and after test scores for various subjects who had of their brains removed in hemispherectomy operations.  The IQ score differences are slight. IQ tests don't involve learned information, but almost any IQ test would be largely a test of memory, as it would be a largely a test of ability to read test questions.  

On the same pages we have before and after test scores for Peabody Picture Vocabulary Tests given to various subjects who had  half of their brains removed in hemispherectomy operations.   In these tests, someone is shown picture cards like the one below. The tester speaks a word corresponding to one of the pictures, and the subject tested is asked to point to the correct picture matching that word.  These tests are tests of memory retention after removal of half of the brain.  On these memory tests there was no decline in the score of 21 subjects mentioned on page 248, and no decline in 7 subjects mentioned on page 250. 

The 2021 paper "Preserved Cognition After Right Hemispherectomy"  by Mark Bowren, Jr,  Daniel Tranel and Aaron D. Boes tells us the fairly recent case of a woman who had almost the entire right half of her brain removed, but is apparently suffering very little cognitive damage from this removal. We read that the woman had a brain stroke at age 29, and that doctors treated her brain problem by removing almost all of the right half of her brain, in an operation called a hemispherectomy. We read that "In the days after surgery, she was described as alert, cooperative, and having normal language and interactions with her providers." We read no mention in the paper of a loss of acquired memories.  

The phrase "having normal language" is a very important indication that learned knowledge was preserved after almost all of the right half of the brain was removed.  Every time a person uses language in speech, that involves a use of acquired memories. Every single use of a particular word requires a memory of the definition of that word.  

Also we read that two months after the stroke, this patient CB had "intact expressive language and reading comprehension."  The paper does not tell us how many weeks after the stroke there occurred the removal of almost all the right half of the brain. But from the timeline given we know that this sentence refers to some time less than two months after the operation occurred.  Because you cannot learn a large fraction of a language in less than two months, we can presume that the patient had "intact expressive language and reading comprehension" directly after having had almost all of the right half of her brain removed, particularly given that we are told that the patient had "normal language" days after the operation. 

In a scientific paper ("Why Would You Remove Half a Brain? The Outcome of 58 Children After Hemispherectomy −−The Johns Hopkins Experience: 1968 to 1996") we read about how surgeons at Johns Hopkins Medical School performed fifty-eight hemispherectomy operations on children over a thirty-year period. Eleven of these children had the left hemisphere of their brains removed; most of the rest had the right hemisphere of their brains removed.  The paper states this:

"Despite removal of one hemisphere  [i.e. one half of the brain], the intellect of all but one of the children seems either unchanged or improved....Although there have been major concerns about loss of language after left hemispherectomy, all eleven of these children have regained virtually normal language....It is tempting to speculate, that the continuous electrical activity of these severely dysfunctional hemispheres interferes with the function of the other, more normal hemisphere. This might explain why motor function improves after hemispherectomy and why language recovers after removal of the dysfunctional left hemisphere, but does not seem to fully transfer before surgery. Perhaps it also partially explains intellectual improvement in these children after removal of half of the cortex. We are awed by the apparent retention of memory after removal of half of the brain, either half, and by the retention of the child’s personality and sense of humor."

There is a reason why we can be confident that removal of half of a brain in hemispherectomy operations does not cause any major loss of learned memories.  If there was a case of any such thing happening, you can believe that it would be endlessly recited by those who wish for us to believe that memories are stored in brains. But there is no such case that is cited. 

The visual below "speaks volumes" on this topic. It is the result of a search on Google Scholar for "amnesia after hemispherectomy." "Hemispherectomy" is the standard name for the operation that has been performed thousands of times, in which half of the brain is removed to stop very bad seizures. "Amnesia" is the main term used for a loss of episodic memories.  Any search on Google Scholar will produce very many results when there are cases corresponding to such a search. For example, doing a Google Scholar search for "vision loss after automobile accident" produces many results. But doing a search for "amnesia after hemispherectomy" produces zero results.

amnesia after hemispherectomy

Entitled "Man With Half a Brain," the 1912 newspaper article below (which you can read here) tells us of a soldier who was shot in the head. First, we are told that he lost his memory, but then the article says that "gradually his memory has returned, and he recollected what happened in his childhood." Then the article tells us this: "And now he remembers everything up until the third day before he was shot." 

recovery of memory after losing half of brain

The news story here documents a very clear case of the preservation of memory after the removal of the left half of the cerebrum. We read of a 47-year-old man who had the left half of his cerebrum removed. We read this:

"Dr. Smith said the patient's memory of events before the operation 'was well preserved, much better than anyone expected.' Tests following surgery show Coe can perform many functions traditionally thought impossible after removal of the brain's dominant hemisphere. Immediately following surgery, Coe still had the ability to speak spontaneously."

A report like this does not merely contradict the claim that the brain is the source of the mind. It also contradicts the claim that the brain is a storage place of memories. 

The results discussed in this post deserve to be pondered at great length. The results indicate very strongly that the human brain is not any storage place of human memories. After considering such results, you should also ponder the most important null result of neuroscience research: the fact that brain tissue from thousands of living and recently deceased humans has been microscopically studied at great length, with the most powerful microscopes; but no one has ever found the slightest trace of learned information or any episodic memory by such microscopic examination. No one found a single phrase, a single word or even a single letter of the alphabet after microscopically examining brain tissue. Nor did anyone ever find by microscopic examination of brain tissue any trace of anything a human ever saw or heard. 

Friday, June 27, 2025

He Had Half a Brain But "Superior Intelligence"

The failure of neuroscientists to adequately study minds is a very severe failure. You can get a PhD in neuroscience while making only a perfunctory study of human minds.  An examination of the courses required to get a Master's Degree in neuroscience will typically show that only one or two courses in psychology are required. Doing a neuroscience PhD dissertation typically involves some highly specialized research on some very narrow topic, research that does not require much in the way of additional study of human minds and the mental capabilities and mental experiences of humans.  The topic of human minds and human mental experiences is a topic of oceanic depth, requiring years of deep study for someone to get a good grasp of the full range of human mental states, human mental capabilities and human mental experiences. Very strangely, a typical neuroscientist is someone who will feel qualified to pontificate about what causes mental experiences, mental states and mental capabilities, even though he typically has done little to very deeply study mental experiences, mental states and mental capabilities.

Ask a neuroscientist to describe the best examples of high capacity and high accuracy in human memory recall, and you will be likely to get a shrug of the shoulders, or an answer that is wrong.  Ask a neuroscientist to describe the best examples of human performance in tests of extrasensory perception (ESP), and you will be likely to get a shrug of the shoulders, or an answer that is wrong. Ask a neuroscientist to describe the best examples of humans learning or memorizing things very quickly, and you will be likely to get an answer showing no study of such a topic. Ask a neuroscientist to describe the fastest examples of human calculation involving no use of any objects such as pencil, paper or blackboards, and you will likely get an answer that fails to describe the most impressive cases. 

Rather amazingly, it is also true that very many neuroscientists are not very deep and broad scholars of the topic of human brains. A typical neuroscientist may be able to tell you in very great detail about some narrow facet of human brains, and may be able to tell you in the greatest detail about how to use some machine that is used to study brains. But the same neuroscientist may have failed to properly study the topic of human brains in a way that involves learning about every relevant thing you could about human brains. Ask that neuroscientist to tell you what happens when you remove half of a human brain, and you may get an answer that is wrong. Ask that neuroscientist to tell you how reliably chemical synapses transmit nerve signals (action potentials), and you may get an answer that is wrong. Ask that neuroscientist to tell you how quickly a brain electrically shuts down when the heart stops (reaching a state called asystole), and you may get an answer that is wrong. 

Part of the job of properly studying brains is to study very thoroughly all of the most impressive cases of high mental performance despite very high brain damage. Relatively few neuroscientists show signs of having studied such a topic. In order to properly study such a topic, you must study unusual medical case histories.  Very many of the most important and relevant medical case histories are recorded in books, newspapers and magazines. But can you ever recall reading of a neuroscientist searching newspapers for unusual case histories in neuroscience? I can never recall reading of such activity by a neuroscientist. 

Luckily there are some web sites that contain very many of the most relevant examples of such medical case histories that are relevant to the question of whether the human mind is the source of the mind and whether the human mind is the storage place of human memories. One of those sites is the very site you are reading.  In my series of posts labeled "High Mental Function Despite Large Brain Damage," which you can read here, I describe many of the most important case histories that are  relevant to the question of whether the human brain is the source of the mind (keep pressing Older Posts at the bottom right to read the whole series). Now let me provide another such case, one I learned about from searching old newspaper articles for a use of the phrase "half a brain." The 1976 case is one that you can read about using the link here. Below are some excerpts from the newspaper article.

half a brain and superior intelligence

We read of a young man named Bruce Lipstadt who had a hemispherectomy operation when he was five years old, an operation that removed the left half of his brain.  Operations of that type are only done when someone is being plagued by very severe seizures, and the seizures cannot be controlled by medication.  The operation was done because as a young boy Bruce was suffering from 10 to 12 seizures a day. 

We are told that despite having the left half of his brain surgically removed, Bruce can ride a bike, swim and play sports. We are told that Bruce got an A grade (the best grade) in a course on statistics at a university. We are told Bruce's speech is normal. We are told that "although not a genius, Bruce has superior intelligence." We are told that Bruce works as a traffic controller, and that next spring he will get a degree in sociology from a university. 

The 1976 newspaper article here gives us some more details on Bruce Lipstadt. We read that his IQ tests showed his verbal IQ to be 126, well above the average IQ of 100. We read this:

A verbal IQ of 126 in a subject who had the left half of his brain removed is a result that would seem to "make mincemeat" out of claims that the brain is the source of the human mind. One of the accounts above mentions an authority named Sugar. The Bruce Lipstadt case seems to be the same one mentioned in the scientific paper here co-authored by Oscar Sugar MD, one entitled "Development of above normal language and intelligence 21 years after left hemispherectomy."

Below is a news account from 1937.

half a brain and superior intelligence

Even more dramatic cases of this type can be found by studying the cases of John Lorber, who reported above-average intelligence in quite a few subjects who had lost almost all of their brains due to disease. A scientific paper states this:

"[Lorber] described a woman with an extreme degree of hydrocephalus showing 'virtually no cerebral mantle' who had an IQ of 118, a girl aged 5 who had an IQ of 123 despite extreme hydrocephalus, a 7-year-old boy with gross hydrocephalus and an IQ of 128, another young adult with gross hydrocephalus and a verbal IQ of 144, and a nurse and an English teacher who both led normal lives despite gross hydrocephalus."

The newspaper account here tells us of a young girl who had the right half of her brain removed, and who can "speak clearly" after having had 80% of the right half of her brain removed.  The newspaper article here tells us more about the same girl. After describing the operation that removed almost all of half of her brain, the article states, "Many of her memory functions, such as her bilingual speech and comprehension skills, have remained intact, Friedman said."

The importance of such an observation can hardly be overemphasized. Bilingual speech (speaking in two languages) requires a massive amount of previous learned information. If the human brain stored memories, we should never expect bilingual speech to survive the removal of half of the brain. 

The article here tells us of Christina Santhouse had the right half of her brain removed in a hemispherectomy operation to stop seizures. We hear no mention of any loss of memory. We get a depiction of a 14-year-old child entering high school, just as a normal 14-year-old would do. 

hemispherectomy

The writer gives some creative but nonsensical explanations for the lack of any big mental effect from removing half of the brain. We are told the fairy tale story that neurons "haven't decided what they want to do when they grow up."  We are told the groundless claim that one side of the brain takes over the functions of the removed half. A much better explanation is that the functions attributed to brains were never actually produced by brains, so you can lose half a brain with relatively little effect. Your biggest laugh when reading the article is the writer's claim that "memory resides in both hemispheres of the brain, so there is little danger of losing it" when half of the brain is removed. This is as silly as claiming that you wrote your diary by filling up two thick diary books, so you won't be losing information if you burn one of those two thick diary books. 

A similar account can be read in the 1987 story here, where we learn of the preservation of learned knowledge and memories in Beth Usher, despite an operation removing the left half of her brain. 

The newspaper article here notes a case of a man who had the right half of his brain removed with "apparently no mental changes at all after the operation."

hemispherectomy with no mental damage

Thursday, June 5, 2025

They Did Well After a Huge Loss of Brain Tissue

The 1935 newspaper account below (which you can read here) is entitled "Half a Brain Good As Whole." We read of operations removing a half a brain, "without the least reduction of intellectual  ability."

half a brain is as good as whole

An article on Buzzfeed.com is entitled "Autopsy Professionals Are Revealing The Most Bizarre Anomalies They've Seen, And Wow, The Human Body Is Truly A Wonder."  We hear some amazing stories about autopsies revealing brains that are mostly gone. 

The accounts are anonymous, giving them less credibility than testimony from named witnesses. But only a very tiny fraction of the population seems to realize the philosophical significance of an autopsy report showing someone who had few symptoms had huge brain tissue loss. So we can rather safely assume that these stories are not being made up to score points in the debate about whether the brain is the source of the mind. 

One user reports this coming up in an autopsy:

"An old woman with an incredibly thick skull all the way around. Her brain was much, much smaller than it should have been, but according to her family, she was fully functional and displayed no deficits of any kind. She actually ran her own cheese-making company and died from a carbon monoxide leak. Strangest case I ever saw!"

Another user reports this:

"I did an autopsy of a young kid, around 10 years old, who had hydrocephalus and was quadriplegic, yet retained some of his normal functions, like talking and understanding — albeit minimally. When I opened his skull, there was no brain. I was shocked. This was my first time witnessing something like this. There was approximately 1.5 liters of fluid and just an empty skull. The brain was so severely atrophied it was smaller than a golf ball."

How can someone do talking and understanding without a brain? Only if the brain is not the source of your mind. 

Another user reports this:

"I observed a lot of things during my professional autopsies. The most notorious was a guy with four .22 bullets in his cranium. He didn't claim pain and apparently lived a normal life."

We can only imagine how much brain tissue must have been lost in total when the last of these four bullets appeared in the person's brain. But nonetheless we are told he "lived a normal life."

Compared to such a case, the case reported below is much less impressive:

"An 85-year-old patient had a tumor in her brain. It was the size of a golf ball on her right lobe — unknown to her before death." 

The 2024 article here is entitled, "Doctors Successfully Remove a Tennis Ball-Sized Tumor in an 8-Hour Surgery." We read of a woman who had a huge brain tumor of 7 to 8 centimeters. We have a visual showing the tumor. The tumor appears as a whitish mass. 

huge brain tumor

We get a vague listing of some symptoms the patient suffered, without  much of anything in the way of specifics. Referring to resection of the tumor (which means removal) we read this:

"Radhika underwent a successful bifrontal craniotomy, guided by navigation and tumor fluorescence technology, allowing for complete excision of the tumor. Remarkably, within one week of the surgery, she returned to her normal life."

She returned to her normal life? That's not what we would expect after the removal of so large a part of the brain, under the hypothesis that your brain makes your mind. 

The story below (which you can read here) describes children who had half of their brains removed to treat epilepsy. The story flatly states that the children "do not lose any of their intelligence, but their fits and antisocial behavior disappear, according to Dr. Eugene P. Spitz of Children's Hospital, Philadelphia." 

hemispherectomy effect on intelligence

Below (from the news account here) is a description of tests on the surgical removal of half of the brain of monkeys. The result is one we might expect under the idea that the brain is not the source of the mind. 

half a brain is good enough

Here is a new story from 1933 noting "no changes in intellect" after an operation that removed "almost all of the right half of a woman's brain."

removal of half of brain

Below we have a 1937 newspaper account (which you can read here) of a woman who had the right half of her brain removed in an operation. We are told that after this operation she had an IQ of 115, which is 15% higher than average. This is not what we would expect under the hypothesis that the brain is the source of the human mind. 

above average IQ with half a brain

Below from a 1957 newspaper is another case of someone doing very well intellectually after the removal of the right half of the brain. 

half a brain normal intelligence

In the news story here, we read that "Mark, of Palm Bay, Fla., is reading better and playing longer since the left side of his brain was removed in May." Note the exact words: "reading better," not reading worse. The news article here tells how a brain tumor of between 5 and 7 centimeters (about 2 to 3 inches) was discovered in the brain of the manager of a major league baseball team. The tumor was in the left front part of the brain, the same part reputed to be involved in executive functions. The manager had just successfully managed the American League team to victory in the All Star game. 

The news story here documents a very clear case of the preservation of memory after the removal of the left half of the cerebrum. We read of a 47-year-old man who had the left half of his cerebrum removed. We read this:

"Dr. Smith said the patient's memory of events before the operation 'was well preserved, much better than anyone expected.' Tests following surgery show Coe can perform many functions traditionally thought impossible after removal of the brain's dominant hemisphere. Immediately following surgery, Coe still had the ability to speak spontaneously."

A report like this does not merely contradict the claim that the brain is the source of the mind. It also contradicts the claim that the brain is a storage place of memories. 

The 1963 newspaper account here is entitled "Monkeys With Half a Brain." We read this:

"Fifty monkeys have had half of their brains removed. Their memories appear to be as complete as before surgery. Until this experiment was made, even doctors thought that such surgery would affect memory....Not only is memory retained; the monkeys are alert, intelligent, sociable, and have the same enthusiasm as doing things as before....What are some of things the team has discovered from observation of monkeys with half their brain removed? The monkeys remember how do things taught them before surgery. Such as which of two blocks of wood place under them has a reward under it -- a raisin or other food. Fears are recalled....'While the rhesus monkeys we test remember everything taught them before surgery, it takes them twice as long to learn something new as monkeys with both half of their brain,' explains Dr. Kruper. 'But the important thing is that they DO learn, even if it does take them longer.' "

I have by now published posts describing many different cases in which learned knowledge and episodic memories were well-preserved after the destruction of the left half of the brain. I have also published posts describing many other cases in which learned knowledge and episodic memories were well-preserved after the destruction of the right half of the brain. You can read about such cases in the text above and in my posts here, here and here. Such cases are all cases deserving the closest study by any neuroscientist claiming that brains store memories. The failure of most neuroscientists to collect and study cases of this type is a severe example of dereliction of duty, and a bad example of people failing to study whether a very important claim such people are making (the claim that brains store memories) is supported or discredited by observational evidence. 

Then there is the case of Sharon Parker. She is described in a 2003 news story entitled "Success of Nurse Who Lost Most of Her Brain." You can read the story here. We read this:

"When she was a baby, Sharon Parker's parents were told a rare and incurable condition meant she would not reach her fifth birthday.

She was left with only 15 per cent of her brain and there was little hope she could lead a normal life. But she defied the experts to become an astonishing success story.

Now 39, Mrs Parker is a nurse with a high IQ who is happily married with three children....She was diagnosed with congenital hydrocephalus - water on the brain - when she was nine months old. Doctors drained the liquid from her skull with a tube but her brain mass had been compacted in the outer edges of her skull, leaving a gaping hole in the middle....As a 16-year-old, she passed eight O-Levels and her IQ was later found to be 113, putting her in the top 20 per cent of the population.

The hydrocephalus has left her with a below-average short=term memory so she carries a notebook to remind herself to do things. However, tests have found that her long-term memory is better than average.

After leaving school, Mrs Parker decided to become a nurse and soon after starting her training, she met her future husband David, a builder who is now 45. The couple were married three years later and have three children...

She often participates in studies, including one recently in Ohio when she was examined by one of the world's leading experts on brain mass. Graham Teesdale, Professor of Neurosurgery at the University of Glasgow, said she demonstrated how adaptable the brain can be even when it is incomplete. 'She shows how the brain has an immense capacity to cope and adapt,' he said. 'Some people with the same acute problem experience problems in thought processes but others are able to function totally normally.' "