"Theophilus Samuels" <theophilus.samuels at btinternet.com>
> [snip philosophic stuff]
> Sure, given that the immune system uses a template to generate billions of
> different antigen recognising complexes, this also implies that the system
> is static, in the respect that during our entire lifetime this creative
> process never changes. In the brain however, one must always remember the
> word 'subjectivity', i.e. what may be 'very painful' to someone may only be
> 'painful' to another.
This is same as saying the brain is shaped by experience. Agreed.
Consider another example: I read an experiment where a third eye is
planted on the frog embryo resulting in innervation of the tectum from
3 eyes*. I dont live close to the library, but i guess the 3-eyed frog
was able to see with all 3 eyes, though it probably experienced a different
sense of vision than ordinary frogs. Similarly I guess a human embryo can
grow up having 3 legs and still be able to learn to walk. This can happen
because the brain is plastic and synapses are broken/reformed/stabilized
according to electrical signaling (the Hebbian view).
*Martha Constantine-Paton et al (1978) Eye-specific termination bands in
tecta of 3-eyed frogs. Science 202:1570-1573
In control theory lingo, the brain is molded into "intelligent behavior"
through positive/negative feedback. For example (someone else said this
in here before) the baby cries all the time because thats the only thing
it can do, ie it generates the full spectrum of behavior. Then the
feedback of emotions / drives etc causes "bad" circuits to be eliminated.
(Postnatal brain development is characterized by a "rise and fall" pattern,
eg total number of synaptic connections plotted against age.)
ie a feedback loop in multiple dimensions of love/hate/fear/etc/etc.
another support to this hypothesis (mine =)) is that when one experiences
great expectations followed by great disappointment, one usually does not
adjust to it immediately, but has to "sleep it off". So maybe the brain
is trying to rewire itself during sleep. (Amount of sleep also decreases
with age!!)
> If we were to consider a basic construct for the sensation of pain, in the
> beginning (i.e. neonates) then there might be some way of recognising this
> sensation by 'reading the mind' (I'm not saying that there is!), but as time
> passes this construct could, in essence, evolve into something completely
> different from the original because of the subjective experiences of the
> individual. In which case, if you wanted to read someones mind then you
> would have to possess every single 'neural reading' for that individual,
> i.e. it's probably impossible to use any form of template to read the mind
> of any individual picked at random from the population unless their specific
> contructs were known [agreeing with your last statement, but with a
> different reason].
If the Hebbian view is correct, there should be some "basic" emotions that
form the "basis set" of more complex feelings. For example, the feeling of
fear is somewhat similar to hunger and also to that of looking down from a
tall building (a thing known as synesthesia).
Which brings in the relation between brain / body (sensory organs and the
PNS), and how brain development is conditioned by these organs. well, i
think i'll read more on this later.
To answer the original question -- there is as yet no way at all, to
stimulate the brain in any localized and noninvasive manner. When new
techniques are available to do that, things might be alot different.