Even if people forget the details of a traumatic event or what is called explicit memory, the emotions associated with that event also known as implicit memory may remain ingrained in the brain for a long  time, says a new study.

In the context of fear, our brain differently encodes contextual memory of a negative event, such as the place, what we saw and the emotional response associated, the results found.

“The study helps explain how the processing of fearful memories can lead to post-traumatic stress disorder,” said project coordinator LluAs Fuentemilla from the Bellvitge Biomedical Research Institute (IDIBELL) in Spain.

The study was published in the journal Neurobiology of Learning and Memory.