Most of the time our brains routinely manage new information and experiences without our being aware of it, and these memories are stored in a verbal or story like way.
When we are traumatized by devastating events such as a car accident or by being repeatedly subjected to suffering such as childhood neglect, our natural coping mechanism can become overloaded.
As a result, devastating experiences are stored in a primitive part of the brain and in raw emotional form. Such primitive raw emotional storage may be usefully considered a kind of “frozen” emotional memory to which we have little or no conscious access.
So even if trauma has been forgotten, painful emotional memories like anxiety, panic, anger, and despair are automatically recalled without our conscious consent, when our primitive brain decides our present is similar to our past. This cripples our ability to live in the present, and thereby may also prevent learning from new experiences.
PTSD treatment and EMDR therapy targets the primitive emotional portion of our brain where horrific memories are stored.