Evolution is incredibly elegant in the way it reversed chaos and led to the ordered structured of atoms that we call life. We human beings are the pinnacle of that process, having been given a forebrain that is able to consciously exert its influence, as opposed to the subconscious way most (if not all) other organisms live. The conscious brain (CB) is truly beautiful; it condensed the knowledge gleaned from billions of years of evolution and turned it into a computation engine that almost every human being possesses in various capacities. Evolution created patterns in atoms, and your conscious brain is a pattern recognition engine.
The subconscious brain (SB) is the ancient brain, the part imprinted by evolution and responsible for keeping you alive and functioning as a member of your species. Things like breathing, digesting, sleeping, swimming (interestingly, we are all born knowing how to swim), and mating, to name a few. You have these subroutines programmed into you before being born; they aren't learned. The process of digesting food, as an example, is amazingly complex. The muscles in your stomach contract and release in a wavelike harmony to push food along the intestines; you generate chemicals to break down this food, convert it into energy (ATP) and excrete the waste. If these are the number of things that need to be coordinated for a single subroutine (digestion), you can start to appreciate how vast the computational capacity of the subconscious brain is. It is astonishingly more powerful than your conscious brain.
However, it is the interplay between the conscious and unconscious that differentiates human beings (and a few other species) from the vast majority of organisms that exist. Because you will realize, that the CB is able to actively add to the subconscious subroutines. Take as an example walking; you aren't born knowing how to walk, you learn it as a baby by falling many many times before the CB finally gets it. Once it gets it, it sends the learned subroutine to the SB, where it is near permanently stored. The number of muscles engaged when you walk is staggering. Imagine you consciously having to select which muscles to engage when you put a step forward while keeping track of your center of gravity, incoming traffic, tripping hazards, and maintaining a walking speed.
This is the interesting interplay between the conscious and subconscious brain. Your CB can actively update the SB, and because you can choose what the CB focuses on, you can bring to weigh the incredible computational capacity of the SB on complex routines (like learning how to solve a Rubik's cube or play chess). However, your SB is not a thinker; it is a doer. What that means is when your SB is engaged, your sense of time falls away because the SB is just executing subroutines.
Think of the last time you drove (a learned subroutine in the SB) with a friend who you were excitedly talking to. An hour later, do you remember many details about the drive itself? Probably not, because most of your attention was focused on your friend. As we get older, we stop relying on the CB because we have built a big store of SB subroutines. If time is what you want to fill then there are a plethora of routine-subroutines to choose from. Which I think is a shame because you are your most human when the CB is in the driving seat.
When your CB is engaged, time slows down, you become more present, and your subroutines are not filling time up; rather, YOU are.
(to be continued in a later post)
Interesting reading:
https://www.quantamagazine.org/reasons-revealed-for-the-brains-elastic-sense-of-time-20200924/
https://www.amazon.com/Biology-Belief-10th-Anniversary-Consciousness/dp/140195247X