ScienceDaily (Oct. 29, 2008) — Neuroscientists at The University of Queensland have discovered a new way to explain how emotional events can sometimes lead to disturbing long term memories.

In evolutionary terms, the brain's ability to remember a fear or trauma response has been crucial to our long term survival.

However, in the modern world, when a similar type of fear response is triggered by a traumatic event such as being in combat; being exposed to abuse or being involved a major car accident, we do not want to repeatedly re-experience the episode, in vivid detail, for the rest of our lives.

During studies of the almond-shaped part of the brain called the amygdala – a region associated with processing emotions – Queensland Brain Institute (QBI) scientists have uncovered a cellular mechanism underlying the formation of emotional memories, which occurs in the presence of a well known stress hormone.

Read more: http://www.sciencedaily.com/releases/2008/10/081028103111.htm