New Evidence that traumatic memories are remembered not repressed.
This is an interesting and important study which provides evidence for memory theories that have been around for at least seventeen years. It's funny the way journalism works. It is also fascinating to try and understand 'conventional thought'. If 'conventional thought' = common belief in the population, then I doubt most of the population has really considered what happens when they have traumatic events in their lives. They probably know that their memory can be poor at the best of times, that some scary events, especially public ones like blackouts or fires are vividly remembered, where as other events are foggier. They may not have a theory for why this is the case and probably use 'repression' in an incredibly vague way. If 'conventional thought' = what scientists think, then we've been thinking it for years. However, I will stress that its great to see longitudinal studies on memory. About time.
Research Turns Memory Theory on Its Head
Contrary to conventional thought dating back to Freud, victims of traumatic events do not subconsciously repress the memories but rather recall them with a clarity reminiscent of reality.
That startling finding comes from a five-year-study conducted by researchers at Dalhousie University in Halifax. The same study, funded by the Social Sciences and Humanities Research Council of Canada (SSHRC) concludes that people have much more difficulty recalling pleasant memories than they do unpleasant.
Led by Associate Professor Steve Porter, of Dalhousie’s Psychology Department, the research team’s findings will be of significant interest, particularly within the criminal justice system where victims’ distant memories of assault, abuse and violence are often discounted based on ideas associated with memory repression.
In the late 19th century, Sigmund Freud developed his famous theory that, to cope with horrific events, people repress memories so their painful effects won’t have to be experienced over and over again.
Dr. Porter’s research suggests the opposite; that victims can recall details of traumatic events such as physical or sexual assault with as much clarity as the day they happened.
“If Freud was right, these would be the kind of events that people would try to push away,” says Dr. Porter. “People tried to push them away but were unable to do so. They were, in fact, haunted by what they experienced.”
On the other hand, the same study found people’s recall of pleasant memories — weddings, births, awards — wasn’t nearly as good.
“The positive memories changed dramatically and began to look very little like the event itself,” says Dr. Porter. “So, if people start to tell you about the good ol’ days, you might want to take that with a grain of salt.”
The theory that memory of traumatic events is repressed has been a staple of criminal defense lawyers for decades. Judges and juries, wittingly and unwittingly subscribing to the conventional wisdom would tend to doubt victims’ recollections.
"We can expect that traumatic criminal experiences can be recalled quite reliably over time," says Dr. Porter. "That doesn't mean there won't be some level of distortion. But the central details will be recalled quite well."
The study, to be published in the journal Psychological Science in May, took place over five years. In 2000, researchers recorded the memories of participants concerning both a traumatic and positive memory. The participants were re-interviewed three months and five years later.
Dr. Porter’s research group included senior graduate student Kristine Peace, graduate students Marcus Juodis and Sabrina Bellhouse, and honours students Leanne ten Brinke and Laura England.

(Anonymous)
If repression is defined as 'unconscious memory processes' (e.g those that occur during PTSD), then scientists have no difficulty grasping the concept. There is a lot of work being done in this area.
If repression is defined as a specific mechanism to lock away traumatic memories, then scientists still have no difficulty grasping the concept, they just currently do not have any evidence supporting the existence of such a mechanism.
Freud had no scientific evidence for repression or whether children would suffer from such a phenomenon more or less than adults. Keep in mind that Freud altered his theory of repression in favour of a theory that women make up sexual abuse. Neither theory has yet stood up to scientific scrutiny.