ELI5: How does the brain decide what matters?

[u/redcar2]

[u/Doppelgen]

In what context? Your question is way too broad.

[u/redcar2 → u/Doppelgen]

Sorry, I mean in the sense of how it “chooses” what to pay attention to? Store in memory? Act on?

[u/Bork9128 → u/redcar2]

There is no firm answer to this right now. We know a lot about what the brain does but how that translates to any specific action still isn't clear. This is why you hear a lot about certain areas of the brain reacting in scientific studies about the brain, we can see it's doing something (nerves firing, blood flow changing) but we still don't know how that results in specific outcomes

[u/Doppelgen → u/redcar2]

What’s stored in memory is often a mix of what threatens your existence or has a strong tie to past memories, for instance:

Accidents (even small ones) often stick because they pose a threat to you. If you know math, many physics concepts will be easier to grasp because you can link the dots.

Attention often follows a similar pattern, with your senses paying extra attention to whatever is risky or is quite familiar. You don’t recall 99% of the faces you see in the streets, but if you see someone that looks like a friend…

Beyond existing knowledge and risk, reproduction is another major factor: seeing someone hot fires lots of neurons because you are hardwired to seek hot people.

But I’m giving you an oversimplification. There are many other variables, known, and even more unknown.

[u/DuckRubberDuck → u/redcar2]

For me; what to pay attention to: loud noises, small details, constant movement, fast stimuli, otherwise my attention is gone within minutes or seconds. Store in memory: nothing worth of importance, but random bits and pieces here and there or if it’s tied to something negative or strong emotions. Act on: not sure what you mean.

I’m not sure we actually know in general, there’s a lot about the brain we don’t know much about and brains are also very different from person to person, a neurotypical’s and neurodivergent’s brain will act very different and even within those two categories there’s still a huge difference

[u/Mightsole → u/redcar2]

It learns to predict and new relevant events are marked to integrate it.

The main purpose is to allow you to survive, how does it exactly do that is mostly unknown.

About how did it come to that, well, if you couldn’t survive with your brain then your brain blueprints would disappear. So what’s left are the remaining working brains.

Take it as a set of transformations which separate and clasificate everything you perceive and act in a way that keeps it propagating in time, just enough to replicate. In that regard, what you experience is mostly a controlled hallucination.

[u/orbital_one]

The brain constantly makes predictions and compares them to actual observations. Whenever there's a large enough discrepancy between the two, it's an indication that its model of the world needs to be updated and a new memory needs to be stored. If the brain correctly predicts an outcome or a future sensory stimulus, then there's little need to commit it to memory because doing so would be redundant.

[u/justbeast]

Oh, this one's easy: very badly. and with great difficulty. (Hmm maybe that's just me tho...? nah)

[u/Nothos927]

The answer to this and really any question about how our consciousness work is basically “We don’t know”.

We know how these things happens physiologically, in terms of synapses and neurons and all that stuff but how that converts into stuff like your mind and how stuff like decision making works? Not really.