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Was the Nobel Prize Awarded Mistakenly? Should the Corpus Book Review iMedPub Journals Archives of Medicine 2021 www.imedpub.com ISSN 1989-5216 Vol.13 No.3:13 Was the Nobel Prize Awarded Mistakenly? Enock Balthazar* Should the Corpus Callosotomy be considered Medical School, University of Buenos Aires, Gervasio Mendez 3249, Carapachay, Buenos a Split-Brain Surgery? Aires, Argentina *Corresponding author: Enock Balthazar Abstract One of the most controversial topics in neuroscience surrounds the Nobel Prize- [email protected]; winning split-brain experiments of Sperry and colleagues. Their experiments were [email protected] carried out on patients who had undergone a callosotomy, which is a surgery that removes the corpus callosum-one of the commissures that connect the cerebral Tel: +5491159120099 hemispheres. After years of research that have allowed us to address some of the major concerns regarding this work, scientists remain doubtful about the validity Medical School, University of Buenos Aires, of Sperry’s findings. This is due, in part, to the number of other commissures Gervasio Mendez 3249, Carapachay, Buenos that also allow for communication between the hemispheres, including the Aires, Argentina. anterior commissure, hippocampal (Fornix), septum pellucidum commissure, the interthalamic adhesion (intermediate mass), the habenular commissure, and the posterior commissure. Therefore, the original assumption made by Sperry, that Citation: Balthazar E (2021) Was the Nobel severing the corpus callosum divides the brain, is an exaggeration of reality: while Prize Awarded Mistakenly? Should the Corpus there is no doubt that the corpus callosum plays the largest contribution in the Callosotomy be considered a Split-Brain passage of information from one hemisphere to the other, it is not the only route. Surgery?. Arch Med Vol.13 No.3:13 After reading and consulting the bibliography of this article, I hope that you will be able to formulate your own opinions about these questions. Keywords: Commissures; Split-brain; Corpus callosum; Callosotomy; Epistemology; Neurophysiology Received: February 02, 2021; Accepted: February 26, 2021; Published: March 05, 2021 Introduction In the fields of medicine and especially neurology, it is difficult to find anyone who is unfamiliar with the name Roger W. Sperry, The Nobel Prize has always held a special place in my heart for its whose work with split-brain patients led to his acceptance of the emphasis on the more positive aspects of humanity. When I was Nobel Prize in 1981. Some textbooks even refer to this work as a child, I was often asked about the greatest thing that I hoped "the ingenious experiment of Sperry." [1]. However, despite an to accomplish when I grew up, and my answer was always the abundance of contradictory information obtained prior to and same: win a Nobel Prize. I don’t believe I had a specific reason at following Sperry’s work, students of medicine, neurology, and the time, or maybe my reason was childish, but as I grew older, I physiology still regard the results of Sperry’s experiments as began to ask myself why this dream was so compelling to me. The incontrovertibly true. Though many scientists have expressed answer finally came to me upon attending my first class at UBA their doubts regarding Sperry’s research, I was unable to find Medical School: because perfection is what we were created to any single article that discussed the experimental errors and aspire in every aspect of our lives and the Nobel Prize is awarded contradictory evidence that might call his conclusions into to those who have approached this perfection. The goal of this question. introduction is to express my appreciation for the prestigious foundation that awards the Nobel Prize and to clarify that I have After days of searching, I realized that perhaps I should be the nothing but respect for the foundation and for those who have one to revisit Sperry’s experiments and offer a more unbiased achieved this honor. perspective. I was hesitant at first, as the task of writing a rebuttal © Copyright iMedPub | This article is available from: http://www.archivesofmedicine.com/ 1 Archives of Medicine 2021 ISSN 1989-5216 Vol.13 No.3:13 against one of the most renowned scientific endeavours in effect on the generation of action potentials-as in the case of neurology would require significant effort. Instead, I considered anti-epileptic agents-can have negative side effects on parts of waiting for my medical career and devoting my time to Sperry’s the brain associated with different types of memory. In fact, experiment. However, I also realized that, as time passes, more anti-epileptics tend to affect both explicit and implicit memory students will continue to accept Sperry’s experimental results as since these two forms rely on the same short- and long-term truth, and perhaps tomorrow there will be more important cases potentiation processes. Moreover, anti-epileptic medication meriting my focus and attention. Though we can never know negatively impacts function in up to 90% of the forebrain, as what tomorrow holds, my former professor Brian Tracy once well as the cerebellum, resulting in side effects on attention, said: "No matter what it takes to accomplish something, when emotional regulation, and memory. you feel the need to accomplish it, do it instantly. Later, you may During the 20th century, the corpus callosotomy became one miss the opportunity, and it could be a huge loss for your life of the most famous techniques for epilepsy management. The and the lives of others.” Therefore, I have halted much of my procedure was designed to prevent the spread of seizure activity other work to focus on what I believe to be an issue of the utmost from one hemisphere to the other by severing the corpus importance. callosum and other commissures. Although Walter Dandy [2], a As scientists, it is our duty to be diligent observers of the true pioneer of this technique, first resorted to corpus callosotomy in nature of reality. Often, however, individual philosophies can the case of a tumor, the first such operations for the treatment of obscure or prevent a scientist’s appreciation of the truth. In the epilepsy were performed in the 1940s by William P. van Wagenen first part of this article, I will cease to be a scientist, donning the and Yorke R. Herren [3]. Specifically, the first operation occurred skin of an epistemologist in order to raise questions regarding on February 6, 1939, which was reported in volume 44 of the the validity of Sperry’s work. In the second part, I will present Archives of Neurology and Psychiatry in 1940. Van Wagenen the physiology of the nervous system as it relates to the different spent the rest of his life regretting his choice to conduct this components of Sperry’s experiments and begin to formulate procedure [4]. conclusions regarding the matter. However, these conclusions In 1960, the corpus callosotomy was again presented as a solution will require further validation by you, the reader, and by other for severe epilepsy by Dr. Joseph E. Bogen. Patient William researchers, in order to gain validity and traction in the scientific Jenkins, a World War II veteran, underwent the operation on community. February 6, 1962. After dramatic improvements were observed Epilepsy and Callosotomy in the frequency and severity of WJ.’s seizures, five additional patients underwent the same operation. Under the care of Joseph Epilepsy is a neurological disorder caused by increased E. Bogen and Vogel PJ, another group of patients underwent electrical activity that can spread throughout the affected brain similar operations in which only 2/3 of the corpus callosum was hemisphere. In the presence of the corpus callosum, such activity severed (leaving the splenius of the corpus callosum intact) [4]. can also spread to the contralateral hemisphere, depending on In the late 1950s, prior to these operations, neuropsychologists its magnitude or intensity. Roger W Sperry and Michael Gazzaniga had begun to study the The study of patients with epilepsy has allowed researchers behavior of animals with severed commissures [5-7]. Although to uncover a great deal of information regarding the higher William Jenkins expressed an interest in participating as a functions of the nervous system. However, some of these research subject after his corpus callosotomy, Bogen and Vogel discoveries occurred accidentally, as in the case of patient Henry instead motivated others to assist with further analyses and Molaison 1926-2008. After exhaustive attempts to understand experiments. and treat H.M.’s seizures, which were extremely severe and life- threatening, his attending physician, Dr. Scoville, concluded that Integration of the Experimental Data the only remaining solution was to remove part of the temporal Epistemology is critical for the advancement of science, enabling lobe, including the hippocampus. He performed the surgery on us to discover the truth by examining the relationships among September 1, 1953; it wasn’t until later that scientists discovered language, logic, and reality. Regardless of our individual that the hippocampus and other regions of the temporal lobe play truths, the three above-mentioned elements are required for critical roles in processing and storing information. Accordingly, epistemological proof. Before moving on to Sperry’s work, let H.M. lost the ability to store new memories and information. us first consider the following: we know that neuroscience is the Although Dr. Scoville regretted his decision, the subsequent subdomain of biology that tells us about the anatomy and function study of H.M.’s condition, until his death in 2008, unearthed a of the nervous system, and that biology is an experimental vast amount of information regarding the neural basis of memory science most often associated with hypothetical-deductive and and emotion. inductive reasoning. To be accepted as valid, the results of any study in the experimental sciences (biology, physics, chemistry, Due to the extremely high levels of electrical activity that are etc.) must employ a specific method of reasoning.
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