In article <4me1qn$60t at scotsman.ed.ac.uk>, shawg at aisb.ed.ac.uk (Shaw
Green) wrote:
> Why does nobody care about the amygdala, what does it do and more importantly
> how does it do it ?
>
Well, Shaw, I don't know who you've been talking to or what you've been
reading, but a lot of people care about the amygdala. In fact, research
into the role of the amygdala in learning and emotion is currently very
popular. Although there are different views on the function of the
amygdala, it is widely believed to be important in emotional learning,
particularly Pavlovian fear conditioning. There are several investigators
working on the role of the amygdala in fear conditioning (e.g., LeDoux,
Davis, Kapp), and I have written a recent review covering some of their
work [Maren & Fanselow (1996), Neuron, 16:237-40]. Others (e.g., McGaugh)
hold that the amygdala has a modulatory role in the storage of emotional
memories in other brain areas, and some (e.g., Gallagher, Holland) posit a
role for the amygdala in directing attention towards biologically
signifcant stimuli. You will be able to pull out reams of data on these
views by performing a lit search on any of these individuals.
While progress has been made defining the role of the amygdala in
behavior, little is still known concerning the cellular mechanims by which
the amygdala exerts its role in memory. For Pavlovian fear conditioning,
we and others have suggested a simple model whereby information concerning
conditional (CS) and unconditional (US) stimuli is associated in the
amygdala through a pairing-specific enhancement of synaptic transmission
in the CS pathway. A mechanism such as long-term potentiation (LTP) may
be involved in mediating enhanced synaptic transmission in the amygdala.
This model is provocative, but there is still a lot of work to be done
before it can be confirmed. Moreover, it doesn't explain the mechanism by
which the amygdala mediates its other presumed functions (memory
modulation and attention increments). This area of research is still
quite young.
Take a look at the book entitled "The Amygdala" (it is edited by
Aggleton), it is chock full of excellent chapters concerning the anatomy,
physiology, and memorial functions of the amygdala. It is sure to turn
you into an amygdala fanatic!
Steve