Explanations of PTSD focus primarily on the road that the head is affected by traumatic experiences. Theorists speculate upon facing overwhelming stress, your head is unable to process feelings
https://www.myptsd.com/am-i-at-risk-for-ptsd/266/ and data in a normal way. It is as though thoughts and the feelings during the time of the traumatic event take on a life in their own, later intruding into recognition and causing distress.
Pre-traumatic psychological factors (for example, low self-esteem) could make this process worse (for example, low self-esteem maybe reinforced by a brutal rape). Post-traumatic reactions by others (for example, a raped girl who is viewed by household as “dirty”) and by the home (for example, physical distress due to memories of the rape) may also are likely involved in influencing whether such symptoms persist. It's hypothesized that only after effective reprocessing of the traumatic event(s) do PTSD symptoms lower.