In article <1998031807310801.CAA15177 at ladder01.news.aol.com>,
uwilwantme at aol.com says...
>>Have we forgotten that you cannot completely localize function to ONE area of
>the brain?
Bravo! It is simplistic and dogmatic to go on shouting that working memory is
a "hippocampal function" or a "prefrontal function" when it is clear that
numerous areas must work together (e.g., the hippocampus AND the prefrontal
cortex, among others). Learning, "memory," and plasticity take place
throughout the nervous system. Mishkin's (and other's) monkey lesions over the
past 20-30 years have only shown that disrupting a circuit by removing its
elements, or by disrupting normal brain function, can interfere with memory.
>NMDA receptors are
>involved in a putative molecular model of learning and memory, LTP.
Typically,
>when you interfere with LTP, you interfere with memory. Interestingly, LTP
>occurs primarily in the hippocampus and most is NMDA receptor dependent. I
>don't think you can rule out the involvement of the hippocampus with the
>molecular information out there.
LTP probably exists as a means for plasticity--whether that plasticity is for
learning and memory, that's another story. (then there's the debate that all
plasticity is learning...). LTP and LTD have been shown to occur in several
brain areas (e.g., hippocampus, cortex, cerebellum...). Its hard to deny that
the hippocampus is involved, but its only one node on the circuit.
Jon
