I can at least say that visual "where" vs "how/what" questions are processed in
different areas of the brain, and that these areas are pretty well established.
Most visual information goes from our retinas through the thalamus and on to
the primary visual cortex, in the occipital lobe. From there, two main
processing streams are recognized: the dorsal stream, processing "where", going
up to the parietal lobe; and the ventral stream, processing "what/how"
information, going down to the lower temporal lobes. As to how these streams
differ qualitatively...well, that's a much more involved issue, I think, and
one that I don't feel up to giving a good answer to. However, I can point out
that these two pathways have very different subsystems that have been evidenced
by brain-damaged patients, among other ways.
Why didn't I say anything about "why"? Because I don't know. Maybe you could be
more specific about what kind of why questions you're interested in. I think
they are diverse enough that different systems subserve different types of why
questions.
