Originally posted by MemoryShock
I propose that the positioning of these two regions of the brain indicate that they are reliant upon each other for the communication of recent (and
long term depending on individual routines) experience to the central nervous
sytem...essentially keeping the body in line with the brains reaction/interpretation of experience for the survival of the individual. In fact,
The Limbic System can be
charachterized as the consolidation and reactionary distribution of the information
collected by the rest of the brain (I am sure that I am over simplifying but I think
that is a sufficient summary for now).
Now the dream process is where we 'download' experience into memory and the
amygdala draws from the associative memory to help determine physical reaction to subsequent experience.
Neuropsych studies show that hippocampectomy and other damage to the hippocampus does profoundly affect the formation of new memory. However, patients
can actually still show implicit learning even with hippocampal damage. The hippocampus is certainly thought to provide a contextual perspective, but
other areas of the medial temporal lobe are also important (rhinal cortices). Moreover, the likes of LeDoux still think the amygdala is a site of
plasticity in certain forms of basic emotional learning.
The amygdala is thought to actually promote memory consolidation via modulating arousal-mediating neurochemicals (e.g., noradrenaline; hence why
beta-blockers are shown to weaken emotional memory).
And the amygdala is well-placed to process implicit information. Predominately because it is involved in the fast thalamoamygdala subcortical route of
processing. This allows rapid preparation to potential threat, even before we are actually conscious of the threat. For example, people who have
complete cortical blindsight can still 'perceive' (although they can't consciously see) emotional faces etc. After the crude subcortical processing
and preparation, the higher cortical processes kick in to fine-tune behavioural response.
Anyways, yeah, the notion of a close relationship between the anterior and medial temporal lobes is pretty well-established.
From the emotion side, the work of Joe LeDoux, Cahill, and McGaugh would probably interest you. LeDoux is the dude who discovered the subcortical
pathway for emotion processing.