Do you ever have every intention of being productive but then you somehow end up pondering various aspects of what we call ‘life’ for hours on end instead? This is a thing that I manage to do on a daily basis. With this blog, my goal is to
systematically (let’s not be too ambitious) document and share some of the thoughts that result from these events, so that perhaps they can amount to more than just connections created within my brain. This first one will be quick, hopefully.
Earlier today I was thinking about consciousness, which is not something I recommend doing if you are seeking a satisfying conclusion. While attempting to formulate my own definition of consciousness, I went back and forth between 1) criteria that would qualify a living thing as “conscious” and 2) completely denying it’s existence (aligning mostly with this). After contradicting myself approximately 8 times, I concluded that I certainly cannot define it. However, if someone used it in a sentence, I would still easily be able to follow what they were saying with respect to the word…
Then I had another thought, specifically, about all my thoughts (literally). And then I entered a very narcissistic state of mind, and asked myself a question of which I now pose to you:
What do you consider to be your “self,” physically?
My initial answer to that was– my DNA, my cells, and the interactions between them and the structures that they form, of course. This is true, but in the past, at least in my studies so far, I’ve focused on DNA, structure and function (but not necessarily how things repeatedly develop to form and function in certain ways), and of course, cells!!
I’m going to layout somewhat of a hierarchy to organize whatever it is I’m trying to get at, but this is not to imply levels of interaction and influence between levels of the hierarchy; rather, it should serve as a representation to guide a frame of thought.
Level 1: Cells
The process of DNA replication and cell division is fucking AWESOME. (I literally have a mitosis poster in my bathroom and I think my roommate hates me for it haha.) If you don’t know much about mitosis and related topics, you should learn about them! I recommend Khan Academy, as well as spending a decent amount of time digesting the information until it “clicks.”
Anyways, mitosis is a process that occurs within your self throughout your lifespan. Most of the cells that make up your body are not the same cells that you were born with! In theory, you are physically a completely different “self” that the one you were born as! (Note: some of your cells are the same, including some neurons in your brain which live a very long time!) I’m using a lot of explanation points because it’s AWESOME!!!
Now you may be thinking, “but wait, if all the chemical & molecular components of ‘me’ are constantly changing, then how am ‘I’ somewhat consistent over time? What about my earliest memories — why can I still recall them?!?”
Well, for one thing, even though the physical parts that make up “you” have changed, your genetic sequence [for the most part] hasn’t. And by genetic sequence, here, I mean the order of the code and of the A’s, C’s, G’s, and T’s. There is actually a lot more to it than that, including activation and expression of the genes within your genome (this can be selective and in response to environmental cues). Additionally, if you want to learn about physical components of your genetic code that do change (without changing the code itself) you should look into epigenetics. It’s something I’m still learning about, and it’s extremely fascinating!
Level 2: Structure
Again, this is not to imply that these levels are independent of each other or ranked relative to each other.
Anyways, I pose yet another question:
What is your earliest memory? How old were you?
Now, to the best of your knowledge, think about how memories might be stored in your brain before reading on.
I actually took a class on learning and memory which was very interesting. There are different types of memory which are formed, stored, activated, etc. by different mechanisms. Here, I’m mostly referring to long-term episodic memory.
A structure in your brain called the hippocampus is involved in consolidation of long-term memory. But it is not directly responsible for storage of long-term memories (nor is any one structure or area in the brain!). In fact, if you had your hippocampus removed, you would still be able to recall your previously-consolidated memories, but you would no longer be able to form new memories (lookup Patient H.M. to learn more!).
Ugh… I said this was going to be short, and it’s already turned into an essay. I’m going to try to sum up:
When you recall a long term (declarative) memory, such as the one you recalled during the question above, you are actually activating not a single place in your brain where the memory is “stored,” but a pathway, made of connections of neurons and systems across the brain. This may include areas related to different sensory information that was activated during which you experienced the event (which are spread across the brain) as well as brain structures and/or systems related to the nature of what you were experiencing, your emotions, goals at the time, etc.
It’s funny, I watched an episode of Grey’s Anatomy (which I absolutely love) where there told a patient that he would die if he didn’t have a certain area of his brain removed. They also told him that it was the area of his brain that stored all of his memories, so after the surgery he would basically not be able to recall any of his past. I was like, “HA! Nope! But it’s OK Dr. Shepherd you’re gorgeous and I still ❤ you.”
I realize that all of this is quite jumbled, but hopefully you can piece together the aspects of memory, levels of structure/function for cells in your brain as well as all of your cells, essentially the code and processes that make up “you” over time, the existence of and your perception of your ongoing experiences, and of course, consciousness.