Atrophy of the hippocampus and other limbic structures has been shown to take place in humans suffering from chronic depression.
It is also sometimes grouped with limbic structures deep in the brain into a limbic lobe.
This structure receives information from the limbic structures to regulate emotional experiences and behavior.
Research has shown that limbic structures are directly related to emotion, but non-limbic structures have been found to be of greater emotional relevance.
There are connecting fibres that run between frontal and limbic structures.
But when the fear circuit is actually traced, he said, the hippocampus and other "limbic" structures do not play much of a role.
The paralimbic cortex lies close to the limbic structures, and is directly connected with it.
In the brain, emotional analysis is carried out by "a common cortical relay, suggesting no direct access to subcortical, limbic structures".
The discovery and linking of various visual stimuli is facilitated and reinforced by direct connections from these areas to limbic structures.
However, this almost immediately ran into trouble when damage to the hippocampus, a primary limbic structure, was shown to result in severe cognitive (memory) deficits.