patrickw@cs.monash.edu.au (Patrick Wilken) writes:
> Thanks for the clarification. My background is psychology; my main area
> being higher-level vision so I certainly am not an expert on the
> neuroscience side of things (though of course everyone interested in these
> issues is slowly drifting into the vortex of cognitive neuroscience).
It is a fun vortex, multidisciplinary science in action. I just wished there was more time to assimilate all the interesting information being produced - I'm interested in so many levels that I can't keep up.
> >I was thinking in this context of structural change in the sense of
> >deviation from normal neural structure (i.e dead neurons), and
> >functional change in the sense of deviation of normal function. The
> >distinction is admitedly blurred, and might not even be perfect for a
> >"wet" system like the brain.
>
> I understand your definition, but isn't it likely to cause confusion?
Yes :-)
> Cell
> death is only one extreme end in the spectrum of structural change that
> occurs in the brain. All long-term memory formation (and for that matter
> forgetting) causes structural change. Chronic drug use obviously causes
> structural change (and by your definition is OK to be called that as its
> not normal), but long-term mood changes probably cause similar up or down
> regulation of specific neurotransmitters. Aren't mood changes part of
> normal functioning? Just because the change is occurring at a level we
> can't detect doesn't mean that it isn't structural, and it certainly
> doesn't mean we won't have the technology to detect such changes in the
> future.
As I said, it might not even exist a good way of distinguishing between "structural" or "functional" changes. Your point is right; there isn't really any distinction between "software" (psychology) and "hardware" (neurology).
> Nikos Logothesis has done nice work training up macaques on unique
> wireframe objects (basically distorted coathangers). He finds that in
> infereotemporal cortex (IT) that, just like the infamous face cells
> detected there, the macaques develop wireframe coathanger cells. This is
> not just a functional change, but a long-term structural change in the part
> of the brain associated with object recognition.
Beautiful!
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