The hippocampus

The hippocampus is a brain structure associated with memory and context. Placing an experience in time and space, marking it as 'it happened in the past', is the function of this structure. In moments of intense stress, the working of the hippocampus can be affected; this can lead to some experiences being remembered cut off from their context. The hippocampus adds context and meaning to the amygdala's raw alarm. This structure helps us tell whether an experience is happening now or in the past.