got to this via a blog post, Casting Memory in Doubt.
Thanks for the memories
But were they simply conforming to perceived social demands, or had their memory of the film actually undergone a change? To find out, the researchers invited the subjects back to the lab to take the memory test once again, telling them that the answers they had previously been fed were not those of their fellow film watchers, but random computer generations. Some of the responses reverted back to the original, correct ones, but close to half remained erroneous, implying that the subjects were relying on false memories implanted in the earlier session.
Some things are disappointing about in science blogging, there is a question that I'd like to know the answer too, but things don't always get answered. Someone posted, "Is it possible that different types of memories are associated with different levels of malleability."
It would be interesting to see experiments on that topic! but a lot of time the comments go unanswered and you don't get to find out.