The Tale of the Dueling Neurosurgeons by Sam Kean
Part I: Gross Anatomy
This section of the book opened up with a story about King Henri VIII. King Henri VIII accrues a massive brain injury in a jousting incident against Nostradamus. The most interesting part to me were the two neurosurgeons we meet in this chapter, Ambroise Pare and Andreas Vesalius. So, I learned that it was taboo for people to dissect, and because of this people such as Galen dissected animals and made inferences about our anatomy based on those animal models. It was really cool to learn that Vesalius spearheaded a movement towards studying our own anatomy in order to learn about ourselves. He was the one to dig up bodies, take them home, and dissect them. In doing so, he was able to disprove many of the scientist who made inaccurate hypothesis on the human anatomy, and was able to create the book De Humani Corporis Fabrica, a gross anatomy book of the human body based on his dissections.
It was quite surprising to read about all of the different forms of treatments used for different ailments, such as using billing elderberry and cauterization for amputees. Both make sense since cauterization is the burning of something/ skin in order to prevent further bleeding or infection. However, Ambroise Pare discovered oil of roses and turpentine, which proved to be much better. Ambroise Pare and Andreas Vesalius are two figures who, as Sam Kean explained, helped revolutionize and pioneer how we do medicine or anatomy is viewed today. They both met each other when they were tending to King Henri who had severe brain damage, but was still very functional. After they dissected Henri’s skull to exam his brain, they found areas of dried blood and puss. This brought them to the conclusion that trauma to the brain can be deadly.
Part II: Cells, Senses, Circuits
In this section, we learn about the discoveries of neuro cells, senses, and circuits through the introductions of characters such as Charles Guiteau, who shot President James A. Garfield. After President Garfield died from complications after being hospitalized, a lawsuit was brought up against Charles Guiteau. Dr. Edward Charles Spitzka was a prime witness declaring that Guiteau was not guilty, but insane.
After Guiteau was executed, an autopsy of his brain was conducted. On the outside, his brain looked normal. However, when placed under a microscope many things, such as “perished neurons that left tiny holes, yellow-brown gunk, a remnant of dying blood vessels” were visible. We learn that Camillo Golgi was the first to start “undoing the neural reticulum theory” because, one night, by accident, he knocked over a beaker of silver solution which landed on a piece of brain tissue. When he went back to look at the tissue, only some of the structures lit up, which were brain cells. He later deduced that brain cells were fused together and that they communicate via their axons. However, since he did not see spaces between these cellular structures, he still believed in the neural reticulum. Santiago Ramon y Cajal, a neuroscientist, disagreed Golgi’s conclusion. Golgi believed that his discovery only solidified the neural reticulum theory, while Ramon y Cajal believed otherwise. Canal saw separate neurons, drawing a diagram of them. Canal then proposed the Neuron Doctrine, which is the concept that the nervous system is made up of discrete cells. Santiago Ramon y Cajal also established that each connection was separated by a junction for which these neuronal cells exchange information, and that neurons communicate from dendrite to cell body to axon.
Leon Czolgosz assassinated President William McKinley and like Guiteau, was sentenced to death. Dr. Edward Charles Spitzka’s son, Dr. Edward Anthony Spitzka declared that Czolgosz was insane. However, like Guiteau, the jury found him guilty and he was sentenced to death. Dr. Edward Anthony Spitzka did the autopsy, and like Guiteau’s brain, found no visible damage. This is when he hypothesized that Czolgosz’s insanity was due to chemical imbalances and insufficient neural circuits.
Next, through the story of James Holman, “the blind traveler”, we learn about the brain rerouting neural pathways in order to compensate for a broken path. For example, some blind people use echolocation in order to navigate through the world around them. James Holman traveled long distances without being able to physically see anything through his eyes, but was able to understand what was around him through his use of “clacking”.
His brain was able to take in information from his auditory cortex, a part of the temporal lobe, where the information is analyzed. This experience alludes to neural plasticity.
Sam Kean then goes on to talk about synesthesia and how it shows that “certain experiences can alter the flow of information in the brain”, which can be temporary[88]. We later learn that Ramon y Cajal found that peripheral nerves can regenerate, however, adult brain cells cannot. Once they die, they are gone. However, Dr. Paul Bach-y-Rita, disagreed with Ramon y Cajal’s findings and said that the adult brain is plastic. he believed in neuro plasticity and built devices that exploited this concept. For many of his devices, he used the tongue as a segway. For example, the number 8 would show up on a screen. Based on that, a device that was placed on the tongue would map out the number. Then the person would say that they were looking at the number 8. The person would practice with this device and eventually get really good at it, or essentially “seeing” with the tongue. As new connections are being made, the more they fire, the stronger the connection becomes.
Inouye mapped out the primary visual cortex, in the occipital lobe, by examining soldiers that were getting shot by Russian bullets, noting each of their occipital lobe injury locations. Hubel and Wiesel placed and electrode array on the primary visual cortex of a cat, and were able to record a neuron firing. They found that the neuron would fire in responded to lines rather than dots on a slide. They found that only “lines within a ten degree orientation would set the neuron off”[110]. They discovered the geographical patterns of the neurons as well as neurons that tracked motion. We also learn about the “where” and the “what” circuits as they relate to the visual cortex. We learn that damage to the “where” circuit can lead to an inability to locate things in space. Damage to the “what” circuit can lead to an inability to tell objects or faces apart.
Names:
Isabelle Dinoire: first partial facial transplant
Clint Hallam: forearm transplant
Dallas Weins: first full facial transplant
Part III: Body and Brain
We are initially introduced to a character, a quadruple amputee, named George Dedlow. He sets the scene up for an exploration into phantom limbs. We learn that Ambroise Pare introduced a new way of amputating which increased soldier mortality. We are then introduced to Dr. Silas Weir Mitchell, who became the expert in phantom limbs and nerve damage. Michelle hypothesized that 95% of amputees did feel phantom limbs. He conducted a study where he found that many of his patients had growths on the area that was cut, which were areas where the nerves still lived. When he touched those areas, he could bring the “ghost” limb back to life because the nerves would send a signal to the brain which still believed that the limb was there. Then the brain would “resurrect” the feelings of the limb as if it were still alive.
From studying people who had no recollection of losing their limb/s, Dr. Weir Mitchell concluded that the brain must “contain a permanent mental representation of the full body - a four-limbed ‘scaffold’ stubbornly resistant to amputation, [which trumped physical physical reality]” [143]. At the time, the only treatment for phantom limb was opiates or pain blocker medication.
There are a few structures that contribute to motor movement, and they include the premotor cortex, the motor cortex, and the somatosensory cortex. The motor cortex is responsible for crude movements, while the somatosensory cortex is responsible for the sense of touch and serves as the sensory feedback system needed. Like the motor cortex, it also has a map of the body, respectively.
Next, we are introduced to neurologist Dr. V.S. Ramachandran, who introduced a low tech, non-invasive, non- opiate solution to treating phantom limb. He introduced the mirror trick.
(Which was actually demonstrated on an episode of House M.D click <a href="https://www.youtube.com/watch?v=qbE2ch-9ZFc"><span class="s2">here </a> to view it).
He would ask the person to close their eyes, then place both limbs into a box that had a mirror facing the “complete” limb. Next he would ask the person to open their eyes, of which they would then see two “complete” limbs. Then the would ask them to squeeze their hands together really hard, after which he would ask them to release the squeeze. many of these people found relief afterward. The pain was finally alleviated. The relief did not last forever, however, and the person would be on a “mirror” regimen.
TED Talk: <a href="https://www.ted.com/speakers/vilayanur_ramachandran">Dr. V.S. Ramachandran </a>
In the next chapter we are introduced to a disease “kuru” that was wiping out entire group of people in New Guinea, an island off the coast of Australia. Dr. Carleton Gajdusek would visit there doing autopsies on the brains of the people who died from the disease. After extracting the brains from their victims, he would mail them to various labs throughout the U.S and Australia. Dr. Stanley Prusiner was the researcher to carry on the next phase of the disease and came up with the concept of prions. Prions are an infectious protein. Since proteins are cells that are not alive, some of which can survive outside of a host, they can survive sterilization and may not trigger inflammation. Prions became the main culprit in Kuru and in other diseases similar to it, Creutzfeldt-Jakob disease. Prions may cause protein plaques that are visible in neurodegenerative diseases such as Alzheimer’s, Parkinson''s, among others.
Now for the pituitary gland. Dr. Harvey Cushing is responsible for determining that the pituitary is also used for communication with the body, but through hormones. He came to this realization by studying people with one type of “damage” or hypo/hyperactivity of this gland. Dwarfs and giants were his fascination, and he studied them. Growth Hormone is the main culprit. If there is an excessive release in growth hormone, during adolescence, possibly because of a tumor on the pituitary, this could lead to a person growing taller and taller without stopping. If there is a very small amount of growth hormone released, this could cause dwarfism. A few cases we learn about are of John Hemens and John Turner. (both giants)
Next, we learn about the Limbic system or middle brain (the emotion circuit) as proposed by neuroscientist James Wenceslaus Papez, and find that it is comprised of the thalamus, hypothalamus, hippocampus, amygdala, and pituitary gland. Even more interestingly, we learn more about how the function of the amygdala was discovered. The amygdala is used for processing fear. Without an amygdala, one would lose the ability to exhibit fear. We learn about his in the case of S.M., who, after suffering from Urbach-Wiethe disease, was let with no amygdalae. The disease killed all of the cells where her amygdalae used to be. After this, she could feel no fear. She would be aware of certain things she did not like, such as snakes, however, when she would come across this animal, she would feel no fear. In fact, she feels a grasp of curiosity. The book also talks about other interesting encounters.
Part IV: Beliefs and Delusions
Neurosurgeon Dr. Wilder Penfield was known as a ruthless surgeon and conducting revolutionary surgery in epileptic patients. One was in his own sister, Ruth, who suffered from epilepsy. He elected himself to do her surgery. While in her brain he removed a lot of tissue, trying to remove all of the tumor he could see. Unfortunately, after an emotional surgery, that included 3 blood transfusions, he decided that he could not reach the rest of the tumor that had traveled to a part of her brain’s left hemisphere and declared the surgery over.
We find out more functions of the Temporal lobe through studies of people such as Dostoyevsky, who suffer temporal lobe epilepsy. Many people with temporal epilepsy usually feel bouts of spiritual bliss. Although interesting, as Sam Kean mentions, we cannot simply cast other religious characters as epileptics because bouts usually last a few seconds, while religious figures could be tranced for hours, and seizures usually paralyze the hippocampus, which is needed for memory. This means that most epileptics usually do not remember what happened during their epileptic episode/ seizure.
Localization research kept reaching new heights. In 1861, Santiago Ramon y Cajal discovered that people who suffered from the power to speak all had lesions in the the same part of the frontal lobe [231]. Gustav Fritsch and Eduard Hitzig used a tapped into different areas of a dog’s brain to make different limbs twitch. Robert Bartholow unethically used french maid, Mary Rafferty, as his guinea pig. He used two electrodes to stimulate different areas of her brain to witness what would happen. Dr. Penfield conducted a similar study, however his was ethical and involved usage of “electrical wires to spark the brain’s surface”. By doing this, he was able to create the famous homunculus.
If our physical bodies were a representation of our sensory and motor homunculus, we would look like Homunculus shown in the picture below from the following website... (https://www.ebmconsult.com/articles/homunculus-sensory-motor-cortex)
Also, Penfield was able to tap the temporal lobes of other patients and induce vivid memories from their pasts.
We are then introduced to the parietal lobe by figures who have experienced parietal lobe damage. One case is former President Woodrow Wilson, who suffered a stroke. After his stroke, among other handicaps, he developed hemispatial neglect. Hemispatial neglect is the inability to notice half of the world [248].
Next, Kean talks about delusions. In writing about different types of delusions, we learn about Capgras Syndrome, named after Dr. Joseph Capgras. Capgras Syndrome is a delusion that all the familiar people in ones life have been replaced by imposters. In explaining this syndrome, Sam Kean draws on similarities from people with face blindness. People with face blindness cannot recognize faces. They may be able to recognize different features, but they cannot recognize the face as a whole. however, in a study conducted by a few scientists, when victims are shown pictures of familiar faces, they may say that they do not know who it is, but, based on their galvanic response, their emotions know exactly who the person is in the picture. This reveals that we recognize faces in two distinct circuits, one bypasses the conscious route, plugging into emotion, while the other requires conscious recognition [253].
Going back to Capgras, it is the opposite of face blindness. In face blindness, the person does not consciously recognize the face, but does have an emotional response. In Capgras Syndrome, the person recognizes the face, but has no emotional response. This lack of emotional response is what triggers the person into believing that people or certain “actors” are imposters. However, if they talk to the familiar person over the phone, without viewing them, they express some sort of emotional attachment. Kean then hypothesizes that of the two circuits, emotions are more primal because the lack of emotional response causes people to invent dopplegangers of themselves and other familiar faces.
Syndromes:
Alice in Wonderland Syndrome, where space and time are warped.
Delusional Bicephaly, delusion of having two heads.
Cotard Syndrome, where the victims believe they have died and are amongst the “walking dead” Some scientist believe, that as in Capgras, there are two circuits that are not working together.
Lastly, Sam Kean writes about an experiment conducted by Dr. Benjamin Libet. He sat a few college students in a room with a button and an EEG cap. He then told them to press the button whenever they felt like pressing it. To his amazement he saw that students made the decision to press the button relatively far before they pressed the button. in examining this study, Sam Kean brings up the manifestation of free will.
My Opinion: I do not believe that this is a example of the possible lack of free- will because the person/ brain is still making a decision, our bodies are just responding to the manifestation of those decisions.
Part V: Consciousness
We are first introduced to Korsakoff’s syndrome, which is the tendency to lie compulsively due to brain damage [272]. Eventually called Wernicke- Korsakoff Syndrome was caused due to a lack in B1 vitamin. The fact that the lying is involuntary raises questions about consciousness. Next we are introduced to H.M., Henry Gustav Molaison, who is a person diagnosed with epilepsy. Dr. William Scoville operated on H.M. removing large pieces of tissue. He removed H.M.’s amygdalae and 3 inches of his hippocampus. H.M. had no working memory. Dr. Penfield performed the same type of surgery on two other patients, of which he removed all of there hippocampus, and they both developed amnesia. Mentally, H.M. was stuck in 1940. He remembered everything before then, but nothing after that. He could not consolidate memories. K.C., another amnesiac, helped us learn that semantic and episodic memory are processed in different circuits. He remembered facts, but could not remember anything about himself. The hippocampus helps with recording both types of memory [287].
We then learn about Shereshevsky, who had an incredible memory. He was a mnemonist. The reason is that everything was like a scene. Every word produced a sound or experience of the 5 senses. Although e had the opposite problem as H.M and K.C., Sam Kean says that his mind is just as bad because he cannot get rid of any of his experiences. He vividly remembers everything and that hinders him.
Names:
Dr. Sperry
Michael Gazzaniga.
We learn that Dr. Sperry, started arguing that the conscious mind was an emergence of neurons, or “emergent property” of neurons [328].
More Cases:
Phineas Gage
Clive Wearing