Nerve Signals and Consciousness

[Proteus]

Why are we conscious of only some of our nervous signals and not of all at the same time? Obviously, we are only conscious of what is passing "now" in our consciousness, yet at the same time, we have countless memories stored elsewhere in our brain of which we are not aware. Yet memories are nervous signals like any else, except that they are channeled back and forth from neuron to neuron instead of taking part in a more complex calculation.

 

I guess this is kind of similar to a computer: it's either currently processing information, or else has the information stored in its memory. But in a computer, the difference between information being processed and stored information is that stored information is static, whereas information being processed is active, in the form of moving signals. In the brain, however, all signals are basically signals.

 

What is it that "activates" a nerve signal so that one becomes conscious of it?

 

No philosophy, please. All I'm asking is what the fundamental neurological difference is between the two. When is a signal part of the greater system that is our current awareness?

[truedeity]

Hope this helps. http://truedeity.wordpress.com/2009/12/20/a-place-for-consciousness-in-nature-perspective-on-%E2%80%98conscious-events-as-orchestrated-space-time-selections%E2%80%99/

[Proteus]

On the other hand, non-conscious cognitive brain functions including sensory processing and control of habitual behaviors can be explained by computation among brain neurons in which axonal firings and synaptic transmissions play the roles of ‘bit’ states and switches.

 

Bit states? As I understand it, unconscious processes are digital and conscious ones analogue?

[tomgwyther]

Brains are very good at filtering out unnecessary information, a huge amount of it is filtered out, otherwise life could be very stressfull.

It's suggested that people with certain forms of autism cannot effectively filter out the unnecessary information, and therefore find the outside world overwhelming, and so tend to focus on very small, specific, often complex single tasks.

As I understand it, consciousness exists in a very fluid state. (Analogies between computers and brains tend not to work very well.)

What we perceive as consciousness is the constant interaction and re-wiring of millions of interconnected neurons.

The differences between remembering something and experiencing aren't all that different.

If I imagine drinking a nice cool pint of beer, some of the neurons associated with that act are activated as if I'm really doing it.

The same is true if I remember a particular instance drinking beer.

if I watch someone drinking beer, those same neurons activate helped along more so by the visual aid

and if I actually drink a beer, again the same neurons activate but with much more information coming from my senses.

 

This constant interaction between memory, imagination (Or abstract thought) and sensory input is what we generally perceive as consciousness.

Your brain is constantly making sense of the world via a mix of current sensory input and retained nuero-physiological structures pertaining to what you're experiencing.

All working almost simultaneously and constantly updating themselves.

Edited January 10, 2010 by tomgwyther

[Proteus]

That's the thing — the activation. What does this activation involve? How are neurons activated, so that we become conscious of them? Unconscious memories, that is, those we are not currently reminiscing and therefore not conscious of, still consist of signals running back and forth between neurons, just as conscious experience. What's the difference? What's the "activation"?

[tomgwyther]

Those memories we are not permanently conscious of are retained as neuro-physiological structures; a certain configuration of grey-matter.

For example, there is a section of the brain which is entirely devoted to Jennifer Aniston, the actress. it lights up when ever you're shown a picture of her. When you not, the neurons kinda just sit there, dormant.

When the picture is flashed up again, information travels down the optic nerve to the occipital lobe at the back of the brain, then through structures in the limbic system where it is ordered around various other parts of the brain, i.e temporal lobe, periatal lobe, motor cortex, frontal lobe for facial recognition, orientation, emotion, short term memory and the bit usually in the pre-frontal cortex which holds specific information about Jeniffer Aniston's face. other parts of the brain may also get involved to induce certain physiological responses, or increase/decrease various neurotransmitters.

All this happens in a split second, and is continually happening.

like a computer network with over a 100 billion work-stations, each connected to about 60 thousand of their neighbours, franticly sending information back and forth.

 

have a look here

http://www.youtube.com/watch?v=AjxJabpjDGo

Edited January 11, 2010 by tomgwyther

[Proteus]

Aha. I had always been under the impression that the neurons actually needed to send forth signals back and forth to simply sustain a memory. I'd first received this wrong information as a child and had since never found any information that explicitly contradicted this. Now it makes a lot more sense. Thank you.

[tomgwyther]

Glad to be of help.

Moreover: the more you do something, the more connections are made.

The more connections there are and the stronger the relationship between neurons; the easier you find it to do a particular task, as there is a stronger set of connections in the brain devoted to it.

The first time I drove a car, found it very difficult, I was using non-car-driving neural pathways to try and operate the pedals, let alone do much else.

Now those brain structures are in place, I can drive without really thinking to much about it, and turn my attention to more important things, such as navigating around London. Which, in itself becomes easier the more I do it.

the structures formed when you practice something are almost perminant physical structures. A bit like web pages are on the internet, they form connections with other servers in various parts of the world and communicate with each other. the connections and content can be changed but don't require constant traffic all of the time.

I've not ridden a bike for a while now, but the 'Brain software' to enable me to do it is still in place; ready to be used.