A tale of brains: A brief recap of today’s neuroscience and its historic milestones


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«I am a brain, Watson. The rest of me is a mere appendix,” wrote Arthur Conan Doyle when his character, Sherlock Holmes, was describing himself. As extremist as it may seem, Holmes was not far from the perspective many have today of what our brain represents. And why shouldn’t they? The human brain is the most complex living structure known to man, capable of more calculations than any supercomputer and of creating more connections that by far surpass the most complex social networks.
The brain controls every aspect of our body. We breathe, eat, react, and process emotions and memories because of our brain. Our thoughts, desires, beliefes, and dreams, are shaped by inner processes going on in this single organ. We develop personalities and become unique individual thanks to the brain’s ability to perform all its variety of functions.
Neuroscience today has a greater experimental capacity and a public outreach than it has ever had before. Novel imaging techniques allow researchers to observe the brain in vivo and record the anatomical and functional characteristics of particular actions. Genetic approaches permit exploring how the brain changes under certain mutations, aiding in the understanding of normal variability and of multiple diseases. In vitro studies reveal how single cells interact so we can comprehend how the brain forms connections and continuously shapes itself. All this development has the single goal of understanding what makes us humans better, because understanding how we think, remember, predict, despair, or get affected by the environment or by disease is the key to a happier and healthier life.
The.com boom has allowed scientists to expose their discoveries to a curious public that every day asks new questions and promotes more research. The ability of the brain to explain why we are the way we are, makes it a common trend topic in social media and stimulates more and more specific investigations. We want to know what our brain has to say about ourselves and we want to know it now. We want to understand deviant behavior, psychiatric illness, and every sort of human response from the perspective of what is going on in those brains. We want to have the capacity to go into those heads and fix them.
Brains, however, were not as popular before as they are today. Getting to where we are has taken debating to establish the relevance of the brain itself, practicing aggressive techniques such as trepanation to achieve enlightenment, and persuading a few to accept that emotions and memories had their seat on the top of our heads.
The brain was first written about by the Egyptians, who described some of its anatomy and the cerebrospinal fluid in the Edwin Smith surgical papyrus (1700BC). Besides these, it seems that they regarded the organ as unimportant and discarded it after death. A little over millennia later, Plato (427-347BC) lectured about the brain and the mental process in the Academy in Athens. Unfortunately, his most renowned student Aristotle (384-322BC) decided to preach that the main controller of emotions and thought was the heart, and that the brain was merely a mechanism to cool it down. This idea remained for a couple of hundred years, until Galen (130-200AD), a gladiator physician, returned the brain to its original place as controller of motor actions.
Galen’s lessons remained for the next 1200 years, which lead other scientist to keep studying the brain and its relation to certain disorders. However, the intervention by Aristotle had created a dichotomy between feelings and thinking that still permeates common conversations in today’s world. One of the affected was René Descartes (1596-1650AD), who claimed that the brain contained some sort of fluid that coordinated the flow between sensory information and action. As a dualist, he believed that the mind and the brain were separate issues that communicated through the pineal gland. Even though his functional hypotheses have been debunked, the discussion between mind and brain is still one of the major debates of current neuroscience.
During the 18th and 19th centuries, the neurosciences started taking a shape a little closer to the one they we nowadays. Previous theories were reexamined and corrected as scientists discovered that nerves worked based on electrical impulses (Luigi Galvani, 1791), and the first neurons were described (Johannes Punkinje, 1837). Scientists such as Paul Broca pinpoint to particular locations for particular actions, such as the Broca area dedicated to speech described in 1862. Localization became a way of exploring the brain, so much so that scholars such as Franz Joseph Gall and Johann Spurzheim (~1800) pushed for phrenology (the determination of personality traits and brain injury be exploring the cranial surface) to be considered a precise science and a diagnostic method. Other researchers, approached the brain from a holistic perspective. Pierre Flourens (1825), for example, ablated the cortical tissue of multiple animals and demonstrated that they were still capable of behaving normally. He claimed that the communication among brain areas allowed other locations to take over the function of injured sites. Interestingly, results today support the localization approach, but also the holistic perspective. As in the case of brain in mind, this debate that started 200 years ago is still and ongoing discussion.
Towards the end of the 19th century, scientists were dedicated to studying the overall anatomy of the brain’s areas and the characteristics of individual neurons. Korbinian Brodmann, a German neurobiologist, published in 1909 his detailed description of 52 brain areas based on the cellular organization of the cortex. His results, though refined and renamed, are still the most widely known and cited cytoarchitectural organization of the human cortex. In this time too, Camillo Golgi developed a nerve tissue staining that allowed him to visualized individual cells and their paths; this staining was central to Santiago Ramón y Cajal, who used it to study extensive examples of neural material that ultimately led him to the Neuron Doctrine, a central dogma in neuroscience. The Neuron Doctrine proposes that the neuron is the anatomical, physiological, genetic, and metabolic unit of the nervous system. Neurons are considered discrete and autonomous cells that interact with each other through synapses, gaps that separate neurons, and transmit information from dendrites to axons. This theory is still a significant portion of the curriculum of any neuroscience course and still affects the perception of the brain of many neuroscientists worldwide. Golgi and Ramón y Cajal shared the Nobel Prize in Physiology or Medicine in 1906.
The 20th century saw the great explosion in neurosciences that we are still experiencing today. Brain areas were better described, functional techniques were developed, and genetic studies became available. The brain changed from being an organ to being the center that holds what constitutes a person, such as the memories, expectations, and preferences. Researches started wondering if complex concepts, as consciousness and soul could merely be the by-product of neural activity. New societies were found to relate the brain to computer science, accumulate neuroscientific information, organize neuroscientists around the world, and expand the reach of brain related discoveries to other fields, such as law, ethics, and philosophy.
In the start of the 21st century the neurosciences seem to be taking one step further: interesting the public. Never before have so many people, unrelated to the field, spend their time discussing the mind-body problem, the problems with localization or holistic theories, or the mechanism behind a conscious mind. Today, the main responsibility of the neuroscientist is to communicate with this interested audience in honest terms what we do know about the brain and what we are still lacking. In the end, it is because of the shared curiosity in understanding ourselves that science moves forward. It might be that one of the questions we get from the social media leads to next breakthrough.

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