I have found there is an important feature to way we handle positive and negative outcomes. It seems to be connected to that sense of achievement that does or does not occur when you reach the end of any given task. I have come to the conclusion that 'this effect of fear based memory' is a construct of having been a creature of the wilderness in the past and that it is due to danger awareness/fear of death.
Let me use a crude analogy based around any game - lets say for instance I am playing a game of chess....
If i win at the game, the moves I used were not questioned, I did not need to return to them to work out how to win because i had won. The outcome of this in my mind is that - Those processes were accepted/forgotten. Accepted to the point where they can be forgotten in the short term. Thus relying on that information to be in the same place as it was when I last accessed it - I.E In long term memory. This process clears your short term awareness in order to make room for new information.
If however I lose the game of chess, the memories of how I lost are stored in short term memory for analysis.
Questions like - Why did I lose?, What had I done wrong (which takes quite some processing)? and What should I have done? all automatically are used. The whole process is then stored in long term memory for later study.
So to conclude it seems clear why we would appear to only have negative memories, whereas under the surface of any negative memories hides the forgotten peices of accepted information.
Very nicely put, and that does explain why we are inherently negative. Have you heard about that dream study? They studied the dreams of 12,000 people over a number of years and they discovered that 75% of our dreams are negative.
Awesome addition to the debate man, thanks for the comment :-)
Cg