Recently, I listened to this interview with Thomas Metzinger, a German philosopher, focusing on mind and consciousness research. Really interesting stuff. I needed to listen twice to get more of the essence, and I am sure if, or when, I listen once more, I’ll understand some more. He’s also been a meditation practitioner for many years, and most likely has experience with mind-altering substances, even though he would not talk openly about it in public, naturally – he only said, when talking and asked about the topic in general, “either you are a scientist who really wants to know, or not…” Anyway, I digress, but you can glean from this short intro that he’s an interesting person.
Scouring the interwebs for more information on Metzinger’s work and interests, I came across this paper. It’s in introduction to Predictive Processing, a theory of how we perceive, and act upon, the world around us, a topic right up my alley. How we make sense of reality, and why people often experience different versions of what everyone perceives, of what is going on at the same place, at the same time, has fascinated me for a long time.
Predictive Processing tackles the issue that we can only perceive effects, but not the causes of these effects, generally speaking. However, we need to know, or be aware of the causes to actually make decisions about our own reactions. While perception is useful for gaining knowledge about the world per se, its main function, from an evolutionary point of view, is to enable efficient, context-sensitive actions, through which we successfully sustain our existence. I leave out the question if we really make rational decisions, or mostly emotional or intuitive ones that we rationalise after the fact as needed, as this is not relevant here.
Now, effects, as perceived, can have different causes. As smile can be honest, or it can be deceptive. In simple terms, Predictive Processing posits that our brain solves that problem by continuously making predictions about what we are just about to perceive, and dynamically adjusts for any errors, either by adjusting the perception, or the interpretation thereof, itself, or by taking action to make things fit, thus minimising the error. That is, our brain is always ahead of what is going on, by working off a hypothesis of the world, based on our model of the current reality. We maybe assume the smile is honest, but permanently adjust for any percepts that violate that hypothesis, and then either just change the view of the situation (deception!), or possibly act accordingly, to make changes to make the situation fit our hypothesis (smiling back might help!), or both. On and on.
As the predictions are based on our own, personal models of the world, it’s obvious what we perceive can be very different between people – our world models are formed by our lifelong experience, and knowledge, and possibly intelligence as well as emotional and intuitive faculties. Our brains are not just passive, stimulus-driven devices. More recent evidence-based research approaches make use of a constructive way of perception, viewing it as an active and highly selective process. People see what they expect to see.
Note – and this is important – that this is not about how we consciously think about what we see – that would be trivial, as that of course is based on our world model as reference –, but about the perception process itself. It happens before we even are aware of what we see, hear, smell, or touch. Of course, the whole process is completely unconscious and autonomous.
I am sure I have somewhat butchered the theory with my simplistic description, but you get the idea, I hope. Anyway, to conclude, here’s a quotation from the paper:
A fruitful way of looking at the human brain, therefore, is a system which, even in ordinary waking states, constantly hallucinates at the world, as a system that constantly lets its internal autonomous simulational dynamics collide with the ongoing flow of sensory input, vigorously dreaming at the world and thereby generating the content of phenomenal experience.
My brain continuously hallucinating, dreaming, simulating – to make sense of reality!
Got to love it.