Where are You?
- Ethan Smith
- Sep 14
- 8 min read
In another post, I shared some thoughts on why the physical boundaries of You might be difficult to make solid on the basis that physical forms change, are composed of smaller lifeforms, and all around might be difficult to exactly pinpoint. So, where are you?
One scenario to consider is how much of you can be removed physically before your experience is substantially changed. For starters, this could be done without risk of death; you could likely lose or replace with prosthetics all of your limbs and even your torso and still be able to recall your name, your favorite foods, or what you studied in school.
Dismissing the shock of how such an event may change your perspective, I think it'd be fair to say the physical processes that conjure your experience and major sense of self, the concepts and memories that comprise us, are mostly unchanged.
Digging a bit deeper, lesion studies on the brain get more interesting.
Phineas Gage was the famous story of a railroad worker who had a metal pole driven through his frontal lobe in a freak accident and, amazingly, survived. While much of his general functioning was preserved, his personality was no longer the same. Where he had previously been known as calm and well-mannered, after the incident he became impulsive, had difficulty planning, was emotionally volatile, and often exhibited inappropriate and offensive behavior. Flashing forward to today, we recognize the place he was struck, the left frontal lobe, is a region of the brain commonly associated with rational decision-making, emotional regulation, and social handling.
Kent Cochrane experienced a motorcycle accident resulting in trauma to the hippocampus and temporal lobes. He lost all past autobiographical memories and the ability to form new ones and also was incapable of imagining future states (once again highlighting the role of the hippocampus in both memories and imagination). Though he could remember facts or historical events in the world. He also recalled his hobbies and personality traits. Additionally, motor memory was preserved. He was capable of both performing previously learned physical tasks and learning new ones.
Dee Fletcher sustained damage to her ventral pathways from carbon monoxide poisoning. She lost the ability to recognize objects visually, meaning she was incapable of recognizing faces, colors, and shapes. Though she was still capable of grasping and interacting with objects quite well. This is not a terribly extraordinary case either, with certain types of blindness resulting in total loss of experienced vision but still a capability to automatically react to a ball thrown to them.
One of the most thought-provoking cases is instances of people who have had their corpus callosum, the section of the brain responsible for communication between the two hemispheres, split for extreme cases of epilepsy. There are a few interesting things that came out of this. When words were shown to only the left visual field (right hemisphere), patients couldn't verbally name what they saw, since language is typically controlled by the left hemisphere. However, they could identify the object by pointing with their left hand. When shown to the right visual field (left hemisphere), they could easily name objects.
A famous experiment was done where patients looked at a diagram split down the middle, showing a chicken foot on one side and a snowy scene on the other. When asked to point to a related image, the right hand would point to a chicken, while the left hand would point to a shovel.
There was also an "Alien Hand" phenomenon where the left hand sometimes seemed to act on its own, like unbuttoning a shirt that the right hand was in the midst of buttoning. Or another experiment showcased how emotional processing was affected. When disturbing images were shown to the right hemisphere, which had a greater emotional response, patients reported feeling upset but couldn't explain why. Meanwhile, the left hemisphere would often construct rational explanations for emotions it didn't understand.
Another example that particularly baffles me is the stories around organ transplants resulting in personality, identity, and personality changes. Not to mention, these cases are observed in transplanting organs not typically thought of as associated with these cognitive functions, like the heart. Admittedly, it’s beyond my pay grade, but I know it’s not unthinkable given how the brain does not exist in isolation. We know, for example, via the gut-brain hypothesis, that activity in the digestive system can affect the brain. At a trivial level, we can imagine that the gut feeds the brain and supplies the amino acids that convert into the brain’s neurotransmitters. Though the relation is even more complex with all kinds of bidirectional communication. Perhaps then, when considering where You are, we need to consider much more than just the brain itself. This also makes the story of Siamese twins who share organs even more complex to think about.
This one may not extrapolate to humans, but I also think about the prairie voles experiment where a relatively simple intervention could change whether they were monogamous or polygamous.
All of these examples illustrate cases where a component of You is lost, revealing that these components are sometimes quite reliably localized to certain brain structures. Cochrane's story suggests that you can maintain who you are without knowing your history. Though time spent in this past you cannot remember still contributes to your concept of self and what you recognize yourself to be. Meanwhile, split-brain studies hint at the reality that You are decentralized but with an intentionally designed stratification and organizational structure. It also starts to get muddy as to which parts are worth considering as You." Automatic motor skills like tying shoes, hunger, and breathing may not feel much like things we use to identify ourselves. Some parts of the brain handle survival functions. Some handle shallow, more impersonal sensory processing. Though the epicenter for our specific, subjective set of experiences remains obscure. Phineas Gage's incident, as well as more recent studies, generally tend to think of the frontal cortex as governing the most high-level components of ourselves, like personality and emotions. It's interesting how you can knock different parts of the brain out and have different parts of yourself survive.
I'd be curious. What is the minimum amount of brain needed for minimum survival (breathing, beating heart)? What is the minimum amount of brain needed to survive and minimally function in society? What is the minimum amount of brain to have experience either internal or external? What is the minimum amount of brain to maintain your sense of identity? And on the other side, is it possible to ablate You, but still be left with a walking, functioning, and mostly normal "zombie?" Some parts of the brain are nearly automatic survival functions, some are for processing stimuli in a seemingly impersonal way, and then some might be more relevant to the specifics of our personality formation.
The overwhelming evidence pointing to You being the result of many decentralized components makes me further think that the appearance of a “single You” is luck. Lucky that all the components managed to properly synchronize in a way that allows them to act as one. Though it also possibly implies the capability of having multiple disjoint selves that have only temporarily made a coalition. Or perhaps there are always only temporary, fleeting You’s that are just trained to feel like the same moment-to-moment with the contiguity of memory.
Outside of identifying the localized components responsible for forming ourselves, I am also interested in: Where do you perceive yourself to be in space? For me, it is some point right behind the eyes, which is probably a result of my vision being to the front and hearing to the sides of this point. Though in prolonged meditative states, this can dissolve a bit, and where you are may feel elsewhere or less like a point.
The Architecture of You
What's left here is the realization that You is the product of a patchwork of many interwoven parts. Tinkering with, configuring, and ablating all of these components reveals a combinatorially large space for different architected minds and corresponding produced experiences.
To me, this is a humbling thought. The space of abnormality is so much larger than the narrow sliver of normality. This isn't just true here but is a fact more generally for manifolds living in high dimensional spaces. There are many ways in which one can deviate while there is only one normal (or relatively few distributional modes). Our constructs reflect this, given that there are 1000s of named medical disorders while far fewer words for describing normalcy.
It is also worth noting that many conditions are correlated, either causing one another or manifestations and symptoms of the same underlying issue. Complications at birth may add noise to your development, causing deviations from the conventional blueprint in usually a perceived negative manner. When you go for a checkup with a doctor, you go over a long list to see if any one part of your health deviates from normal.
The funny thing is, though, many people may have at least one condition. No one is normal, but most people are typical. Allergies, flat-footedness, early balding, indigestion, and all the others. Everything has a probability of occurring, and the odds of you having at least one schtick are relatively high. This is a strange fact of the normal curve in high-dimensional spaces, it begins to look more like a bubble or shell with samples clustering towards the outside rather than the inside, as we imagine with the bell curve, given that it is often the case that at least one dimension will be a larger-valued outlier.
Granted, the isotropic normal distribution is probably not a great model for the distribution of human forms. Conditions are very obviously correlated with each other. I somewhat like Emmett Shear’s notion of somatic integrity, where deviations from normal happen not in one’s but in two’s and three’s and more
Even so, we are relatively centered around normalcy. This is to say, the variance between most people is relatively small. Relatively small in that we're considering a few gene flips and other biological differences, as opposed to having a human vs. dog brain. Much of the human design space, and brain space, is largely uncharted.
Mostly for good reason: most things don't work. If we think about the space of all images, all possible combinations of pixel colors, a profoundly small slice of that reflects coherent imagery. The rest, effectively TV static. When grabbing points at random, broken is the default case; functional and ordered is the special case. Not in terms of frequency of occurrence, as there are driving forces that keep things on manifold, but with respect to how small the space is of normal compared to the vastness of all that is abnormal.
In considering the design of a human, many designs don't work and are unreachable by natural means anyway, like a 2000-pound person who is 4 feet tall is impossible. It lies in an unreachable part of space (I hope). Many of those that could be reachable can result in unviable life from the start. Others treading closer to the fringes of normality may be generally unfavorable, like deafness, OCD, or other neurological disorders. Others may be super-favorable, like a person who does not need much sleep, or has a high IQ.
Though it's worth remembering that nothing is better/worse until an evaluation criterion is introduced. ADHD might be an effective means of quickly switching focus to stay alert from predators in a Stone Age society. Having eyes might have been a costly but useless development in a world without light. Some people have a terrible understanding of directions but can play the piano with their eyes closed. What if peacock feathers repulsed potential mates instead of attracting them? Every phenotype just is, then later receives judgment depending on the state of its environment or the subjectively evaluated feelings we associate with it.
There is a diagram known as the homunculus, which shows the body's organs, resized to show how much brain space is dedicated to their sensory and motor functions.
I'd like to somehow have a similar diagram for how responsible each part of the brain is for your manifested behavior and experience and how it responds to perturbations/ablations. I imagine we'd likely see the frontal cortex sized largely while there may be other parts of the brain that are almost removable. However, this presently feels too handwavy and difficult to quantify.
One thing the homunculus diagram reminds me of is caricature images, which, the way I imagine it, emphasize and enlarge the most distinguishing characteristics of a person, whether this is done consciously or not. As we’ll discuss later, I think we have sets of pattern banks we refer to in our mind used for recognition that reflect facial attributes. Some carry higher signals than others, and I think when we imagine people’s faces in our minds, we cling to the prominent distinguishing factors more so than the “fluff” per se.
Loved the post. For basic tasks I’d say maybe just the Brain stem would be enough. Although it’s interesting to think of the distinction of You in terms of capabilities and personality. You can lose a major chunk of your capability without affecting your core idea of yourself I imagine.
ADHD and other neuro disorders are other edge cases. Medication has often been shown to affect personality so which is the real you then. Same with birth control and other hormonal therapy which affect personality as a whole.
Fascinating to think about