How does the brain 'know' that something is a stable 'fact' in an environment?

Question

Like the walls and floor in the room that you are in. They are stable, they don't move. And you can move in relation to them, knowing that they will stay there. Is this abillity to percieve stability explainable with a Hebbian approach?

Answer 1

I won't be able to explain this in detail, but I think I can point you in the right direction. The brain is a self-organizing system. There are various basic principles that apply to the dynamics of all self-organizing systems. One of the mathematical characteristics of self-organizing systems is the creation of relatively stable points. The mathematics of a self-organizing process is often depicted as a "landscape" containing peaks and valleys. If you imagine a ball rolling along this landscape, you can see that the ball will tend to settle in a valley. The peaks and sloping curves represent dynamically unstable regions where the ball cannot come to rest. (Well, technically the very top of a peak can be a pseudo-stable point where the ball can rest briefly, but a very slight disturbance will send it down-slope in some more or less random direction. Since every system contains a certain degree of random energy, this delicately-balance stability can never last for very long, so it is not really a "stable" point in the long run.) The basic idea is that the ball will eventually get trapped in a valley when the energy of its motion is lower than the amount of energy required to escape from the valley (it is not able to reach "escape velocity" you might say). Obviously the ball will tend to ultimately settle in a fairly deep valley, but may get trapped in "false minimums" for periods of time (meaning that there are deeper valleys into which it could settle, but at the moment it does not have the energy to get out of the valley in which it is trapped). Luckily, there are various sources of more or less random energy that can push the ball from time to time, and sometimes these pushes will be enough to let the ball escape the local minimum, and thus give it a chance to find a deeper valley, or perhaps even a global minimum, if there is such a thing.

So getting to a somewhat more direct answer to your question, what we experience as "objects" in the mind (physically perceived objects like a chair, abstract objects like numbers or ideas of various sorts) are, on this way of thinking, "valleys" in the self-organizing "landscape" of neural dynamics. Another way to think of self-organizing dynamics is to think of whirlpools in a river. The whirlpool is a relatively stable structure amidst the overall chaotic flow of the river. In this metaphor, objects in our minds are like whirlpools in a river. In any case, it is well-known that neural connectivity is a matter of self-organizing dynamics, so even though the precise details have not yet been worked out, the general notion of mental objects being related to relatively stable points in complex dynamic systems is a pretty safe bet.

Hebb's original principle (the Hebbian learning rule) was essentially that if one neuron is stimulating some other neuron repeatedly, then the strength of the connection between the two neurons will be increased. This is most likely going to turn out to be part of the story of neural dynamics that explains the self-organizing character of neural connectivity, but it almost certainly won't be the whole story – and probably won't even be the most important part of it. These are the sorts of details that we are still a long ways from working out.

Answer 2

No...Hebbian is unuseful in this instance. Drug induced perception could create synaptic connections with equal effect as normal cognitive repetitions.

Stability and instabilty are relative terms based on the position of the observer.

The physical fact is that everything is in motion and at great relative velocity.

Answer 3

Well why don't you try walking through something stable and them something unstable and you may be able to figure it out for yourself.

Answer 4

LOL, you learn by communicating and touching! Ever heard of " Learn from ure mistakes?". That's like asking " How do birds know they can fly?". Oh yeah, It's a basic instinct to know too....