I saw this old movie called "The Hands of the Ripper". The basic plot of the movie was that there was this young woman (the main character of the movie) who had seen her mother murdered by her father when she was a very young child (about 2-3 years old).
And also, at the scene of the murder there were some shiny objects glistening (jewelry) which she saw. Then later in her life as a grown up, she seemed and behaved like a perfectly normal young woman. And apparently she had no recollection of this traumatizing incident in her childhood. But whenever she would see a shiny object (a glistening necklace for example), for a brief moment she would become violent and homicidal. Then afterwards, she did not remember anything about the murders she had just commited and again continued to live normally.
I should mention that in the movie there was also this supernatural element to the story, but if one would exclude that and think of the main character's behavior from a psychological point of view. Then from this point of view, I personally thought that the movie's plot was extremely far-fetched and unrealistic, but some people I know thought this was very much realistic and something like this could happen in real life.
I personally don't have a degree in psychology, but I have read few psychology books and am very interested in psychology as a hobby. I would really like to know what someone with more knowledge thinks.