are Traumatic memories easier to recall than happy ones?

from yahoo

By Claire Sibonney Thu Feb 22, 12:09 PM ET

TORONTO (Reuters) - Memories of traumatic events are not suppressed by the people who experienced them but can be recalled clearly, according to Canadian researchers.

Sigmund Freud developed a theory that victims of horrific events repressed difficult memories in order to cope with what happened to them.

But scientists at Dalhousie University in Halifax found in a five-year study that pleasant events were more difficult to recall than unhappy ones.

"We were frankly blown away," lead author Stephen Porter said in an interview.

"We were surprised at how consistent (the traumatic memories) were relative to the good memories in life which had deteriorated dramatically and looked nothing like the reports that we heard about years ago."

The researchers interviewed 29 people who had gone through a traumatic event such as a sexual assault or domestic violence in the past few months.

The participants were asked to provide details about the experience as well as a recent happy event such as a wedding, birth of a child, award or vacation.

Porter and his team re-interviewed them after three months and again after four to five years.

Based on a questionnaire with a maximum possible score of 36, the average mark among participants for consistently recalling a traumatic experience was 30, compared to 15 for a positive one.

"I think it's quite obvious that these types of events really permeate our conscious awareness. They were just haunted by them," he said referring to the traumatic events.

"I think this provides evidence that (Freud's theory) is completely off-base," said Porter, whose findings will be published in the journal Psychological Science.

"It really makes good sense to remember the event well in the future so we can avoid those circumstances and maximise our chances of survival," he added.

The idea that memory resilience is increased for non-pleasurable events has been known for years, but Steve obviously didn't remember it. PTSD wouldn't exist unless memories of traumatic events are more strongly embedded, and if Freud was right we'd all be suffering from Post-Wedding-Stress-Disorder or Post-Sex-Stress-Disorder instead. There's evidence that the pathway imprinting for a memory is affected by the levels of adrenalin and endorphins, and it's perfectly sensible to remember dangerous narrow-escapes more vividly than happy, safe events if you're trying to avoid beting eaten, poisoned or stood on by an elephant. In animals and very small kids it's a physical threat response (they learn from bad tastes, pain, etc.) but in adults we also trigger resilience based on social factors - a memory where you were really humiliated or embarrassed is strong because in a social species like ours it used to matter a lot for survival, mating rights and access to food if you were respected by the group.

Post-traumatic selective amnesia is thought to be more of a complexity effect than a blocking effect - your brain is having a hard time sorting all the information and linking it, so for memories with a very strong mixture of emotions and experiential memories (things you saw, did, heard, etc.) sometimes your brain throws it back into the in-tray for a while. The memories are stored (they can be found by hypnosis) but they're not indexed properly. There's no reason why forgetting a past event is going to make your life safer or 'protect' you from anything - it's better to learn that tigers are scary and have nightmares than to pet every one you see.

mG