THECONSCIOUSNESS CONUNDRUM OF
Akila Raghavan explores the yet unsolved scientific mystery of human consciousness.
Y
ou’ve stubbed your toe on the corner of your coffee table. You feel pain.
Your partner sends you a romantic text message. You feel loved. You shovel a heaped spoonful of chocolate pudding into your mouth. You taste sweetness. You trip over seemingly flat ground in front of a large group of people. You feel embarrassed. We are all capable of feeling all these emotions and sensations. This is because we are all sentient beings – we have a consciousness. Simply put, consciousness embodies everything that we experience. However, attempting to understand consciousness has proved to be anything but simple for scientists. Our brain, an unassuming lump of grey jelly, is an incredibly complex organ consisting of around 100 billion cells called neurons, which are each connected to 10,000 others. This results in an intricate network of over ten trillion nerve connections. Despite our vast understanding of the brain and how it works to produce human behaviour, scientists are no closer to figuring out how this mass of tissue that sits nestled comfortably within our skull can give rise to what we know to be our consciousness. How does the feeling of loneliness stem from the constant firing of chemical and electrical signals between neurons in our brain? How does this mass of neural tissue function in order to allow us to experience the sensation of itchiness? The short answer is – we don’t know yet. The conundrum of consciousness appears to sit right on the boundary of philosophy and science leading researchers to question whether conventional scientific methods will ever be able to solve this mystery. Taking the philosophical approach, we can trace the problem of comprehending the nature of consciousness and its properties all the way back to the initial work of 17th century French philosopher, René Descartes.
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I, Science
In an attempt to make sense of this, Descartes came up with Cartesian dualism. This concept states that consciousness resides within an immaterial domain he termed res cognitans, or the realm of thought, as opposed to the domain of material things, which he termed res extensa, or the realm of extension. Descartes believed that the interaction between the two domains occurred within the brain. Effectively, this theory assumed that the physical body is separate from the mind. Aside from this first answer to the problem of consciousness, Descartes is also credited with giving us the most famous summary of human consciousness: “I think, therefore I am.” Other philosophers, such as Karl Marx and John Locke, rejected this mind-body dichotomy put forth by Descartes and claimed that consciousness, and therefore personal identity, is not tied to any substance. Psychologist William James has likened consciousness to a stream, in that it is constantly flowing and unwavering despite the changes and shifts around it. Today, researchers studying human consciousness are primarily focused on what consciousness means in both a biological and a psychological sense. The majority of the experiments done in this field rely heavily on assessment of verbal responses given by test subjects, which brings in the risk of subjectivity. In order to determine the accuracy and significance of such studies, scientists must compare these verbal reports to any corresponding activity simultaneously occurring in the brain. That is, they are looking for neural correlates of consciousness (NCC). NCC is defined as the minimal amount of observable neural mechanism that is required for any sort of conscious experience to occur. For example, what must happen in your brain when you experience a sense of calm after yoga? Do your neurones need to be firing impulses in a certain pattern or at a certain frequency? Do specific neurones need to be involved? Or do they have to be located in specific regions of the brain? Research into defining the NCC has observed that the seat of consciousness is much narrower than previously thought. In cases of extreme trauma, such as the severing of the spinal cord from the rest of the nervous system in victims of car crashes,
it has been seen that such individuals still retain their consciousness. Additionally, in situations of accidental surgical mishaps involving misplaced scalpels in specific regions of the brain, patients have recorded that they are unaffected in their ability to feel and experience things. Data from cases such as these all point to the heavily celebrated cerebral cortex of the brain being the region in which consciousness appears to generate. Through the study of patients who have had specific areas of their brain removed and experiments involving the electrical simulations of certain regions, scientists have been able to conclude that the posterior cortex specifically has a definite role to play. This region appears to be responsible for processing not only sights and sounds, but also all the other sensations of life. The study of the brain is not the only area that researchers are exploring when it comes to the science behind consciousness. Scientists are also looking into the intrinsic properties of each individual experience itself. A theory termed the integrated information theory (IIT) postulates that each experience triggers a specific response which is unique to the individual having the experience. Thus, IIT states that there is a cause-and-effect relationship between the properties of such experiences and the complex mechanisms our brains undertake. IIT also predicts that the complexities of human consciousness cannot be replicated digitally. This means that any attempts of programming a computer with consciousness will only result in a simulation of inputted conscious experiences, not a conscious computer itself. Thus, consciousness must be organically integrated into the structure of the system. Should IIT prove to be true, this bodes well for the future of AI – we can rest easy knowing we don’t have a Terminator-esque future ahead of us! Ultimately, the science behind consciousness currently lies in a state of uncertainties and yet to be proven theories. Perhaps the continued advance of technology will allow this research to progress and, one day, solve one of life’s biggest conundrums: how an unassuming lump of grey jelly can emanate the feeling of life.
