mejqb at my-deja.com wrote in message <8ntt6n$9bm$1 at nnrp1.deja.com>...
>In article <39a12868_1 at news3.prserv.net>,
> "Sergio Navega" <snavega at attglobal.net> wrote:
>>mejqb at my-deja.com wrote in message <8nmnvd$eag$1 at nnrp1.deja.com>...
>> >In article <39885cd9_4 at news3.prserv.net>,
>> > "Sergio Navega" <snavega at attglobal.net> wrote:
>> >> MS wrote in message ...
>> >> >It sounds like a premature generalization to say that because
>several
>> >tasks
>> >> >activated one area that it validates a g-factor of intelligence.
>> >Given the
>> >> >role of working memory across complex tasks and the importance of
>> >> >dorsolateral PFC in working memory, couldn't a working memory
>> >impairment
>> >> >account for those findings?
>> >> >
>> >> >--
>> >> >Marcello
>> >> >
>> >>
>> >> I agree. Although I'm sympathetic to the concept of general
>> >intelligence,
>> >> I don't think we have a specific area of the brain responsible for
>> >> it. I think it is premature and somewhat "sensationalistic" to
>claim
>> >> to have found such an area.
>> >
>> >The notion of a specific area of activity and the notion of a general
>> >intelligence factor as propounded in The Bell Curve aren't even
>> >vaguely related.
>>>> I'm not sure why you bring The Bell curve to the discussion, as it
>> offers something that's far from what has been discussed here.
>>It would help if you would actually *read* the thread once
>in a while:
>> "
> Scientists measuring blood flow to regions of the brain have found
> that one particular area (the frontal lateral cortex) was stimulated
> when performing complex tasks. Even tasks that required a wide range
> of cognitive functions did not stimulate numerous regions of the
> brain, as some scientists predicted. This finding gives credence to
> the highly controversial idea of a "g" factor (generalized
> intelligence), as advocated in The Bell Curve.
> "
>
That's exactly my point, thank you. I don't see the relevance of
bringing The Bell Curve to the question of neural localization of
general intelligence. General intelligence factors are abstract
constructions that would be very difficult to correlate with the
performance of any specific area in the brain, which is the main
idea of what I said earlier. However, I see that you prefer to
nitpick with this detail instead of offering comments on my
rebuttals of your previous message:
Copied from previous message
>Balter:
>Well, you might have been able to say that a decade ago when the brain
>was still thought of as an amorphous blob, but since then a great deal
>has been learned about the detailed localized structure of the brain
>and localized function. But as usual, the beliefs of individuals lags
>behind the state of accumulated human knowledge.
>
You might have said that 5 years ago, but not today. Although the
idea of brains as general purpose "computers" without any
specialization is long gone, so is the idea that it is a
pre-specified organ, with "compartments" genetically specialized
in the processing of specific stimuli. Take vision, for instance.
One could take the visual cortex to be an example of a specific area
of genetically specified origin, unable to process nothing more
but visual stimuli. This is not the case.
There's a huge amount of research indicating that the
visual cortex is reused in blind humans to help processing of
somatosensory and auditory cortexes. Cortical columns *change*
in structure because of that, approaching the organization
found in auditory cortex.
Deaf individuals were seen (by fMRI) activating the auditory
cortex in response to visual stimuli related to american sign
language. Only a plastic brain could manage to get that.
Some say about special areas of the brain responsible for the
identification of faces. Yes, there are these areas, the question
is where they come from? From specific genetic instructions or
from self-organization? Recent studies showed that this same area
is used not only for faces, but also for the recognition of
sophisticated visual stimuli by experts (experts in cars, for
instance, also use this area).
So what is being discovered is that brains are not general purpose
organs, but neither fully determined. They are complex systems,
built from general genetic guidances but strongly subject to
the self-organizing effect of impinging stimuli.
Regards,
Sergio Navega.
