Brain Injuries, Philosophy of Mind, and the Realm of the Senses

Brain Injuries, Philosophy of Mind, and the Realm of the Senses

“BRAIN CONFUSING. CONSIOUSNESS WEIRD.”

The connection between our physical brain and the mental mind has been a topic of debate among scientists and philosophers for a long time. Though the exact mechanism(s) for the formation of the conscious experience are not yet identifiable, there is certainly no doubt among the scientific community that the physical connections within the brain are necessary for consciousness to be produced or experienced. Exactly how the conscious experience is generated from physical connections is an issue commonly known as the mind-body problem: the body (brain) is purely physical, yet generates an experience that is nonphysical and seemingly floating in the aether. The conscious experience is intimately connected with proper homeostasis of the brain’s physical cells and circuits, and something as minute as changing the concentration of an ion within the brain can lead to complete disruption of consciousness. As we have learned within the last month of class, physical traumatic brain injuries can cause varying changes in the conscious experience of people who suffer them. In this paper, I aim to discuss how I believe that merging our scientific understanding of the physical brain with philosophical ideas of mind and reality can help us to further understand ourselves and our universe.

To start things off, let’s talk a little more about the brain. The human brain is so complex that the scientific community has only a limited understanding of how it functions, and most of that knowledge surrounds physical processes within the brain. The mind-body problem, as mentioned in my first paragraph, has yet to be solved – while we can study and understand physical processes within the brain and the physical downstream changes produced by them, this knowledge leads us to a cul-de-sac of actually understanding the nature of consciousness. I’m sure that most of the students in this class have heard discussions concerning artificial intelligence and whether true consciousness could be produced from physical electrical circuits on a silicon board, and these discussions usually end with the statement that we have no reliable method of testing whether another “being” is conscious or not. While we can observe the actions and hear the vocalizations of other people which makes it seem obvious to ourselves that they are conscious, there is no way to prove it. For example, we may be fooled by a machine that could accurately imitate consciousness while not experiencing any type of sensation itself. Indeed, the conscious experience is the most subjective thing you can imagine (ha!), and this subjective nature of consciousness has been one of the largest hurdles in studying it on an objective, scientific basis.   Let’s take this subjective nature of consciousness and let it lead us into a discussion on senses. Anybody who has taken an Introduction to Philosophy course has likely heard of externalist and internalist views of the world in the context of perception. These two viewpoints hold different beliefs on whether the causes of conscious sensations actually exist in the world (external) or whether they are purely generated in your mind (internal). For example, when you look at an apple and see the color “red”, is the apple actually “red” or is your brain only generating the experience of “red”? While certain brain circuits are directly linked to adding color to your visual perceptions of the world (you look at an apple and see “red”), these same circuits are active during dreams or mental imaginings, allowing you to perceive color when there is not a physical object in the world causing the perception. This leads to a tricky problem of understanding whether our senses portray the world as it actually is, or whether our senses can be tricked and provide us with an experience that doesn’t match up with reality. There is no doubt that if I place a textbook in front of every student in this class, each student would report that the book has four sides, two faces, and is rectangular in form: our senses seem to be generating an objective view of the physical reality of the world. However, we know that physical changes in the nervous system will lead to perceptions that do not match up with what seems to be objective reality. For example, psychoactive drugs greatly change a user’s perception of the world and the user may experience a textbook that no longer has straight edges, or hallucinate an imaginary perception altogether; a fault in producing certain photoreceptors in the retina will cause a person to perceive a red apple as not red; and, traumatic brain injuries may cause a patient to experience the words on a book’s page as constantly moving instead of staying stationary.

The fact that sensational perception can ebb and flow between accurate depictions of “objective reality” and false depictions of subjective reality makes consciousness incredibly difficult to study. It is classically thought that in order to accurately and precisely study the nature of consciousness, we have to increase our level of control in order to reduce confounding variables. This can be a difficult feat to overcome when studying the nature of a system that we cannot yet fully comprehend. However, I think a fantastic method of researching consciousness is mentioned in the book titled Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts by Stanislas Dehaene. In this book, Dehaene mentions how modern researchers are utilizing anecdotal reports of subjective experiences caused by objective changes to the physical corpus of the brain or environment to develop theories of conscious perception. In other words, the scientific community may have to commit the ultimate blasphemy and rely on anecdotal reports as evidence to build theories of consciousness due to the fundamental subjective nature of consciousness itself. This method allows researchers to discover what physical events are occurring in the brain when subjective mental changes occur (e.g., when a person first becomes consciously aware of a flashing red light). By relying on anecdotal reports, Dehaene and his team of researchers (among others) are able to accurately pinpoint what physical changes coincide with the generation of the conscious phenomena.

Going along with this, I believe that traumatic brain injuries (and physical changes to the brain in general) would be a very useful tool in studying consciousness. As procedures and techniques become more refined and precise, a greater level of physical control of the brain is able to be coupled with anecdotal reports from lucid patients to help formulate an accurate theory of consciousness and the generation of perceptual experiences. As a class, we have learned of many perceptual changes that patients with traumatic brain injuries exhibit, such as an inability to understand facial expressions in the context of emotion, mental visualization anomalies such as “moving words” and decreased peripheral vision, and more. I think that studying these brain injuries in more detail, and investigating what physical changes actually took place to generate the aforementioned changes in perception, will lead to better research methods and study designs for revising our current theories of conscious perception. In doing so, I think the Internalist vs. Externalist debate may be enlightened by novel ideas of the universe and reality, inching us closer to a fuller sense of objectivity and truth.

And who doesn’t want to know the truth of their world?