How trauma can affect memory

During a sexual assault or other traumatic event, the victim typically focuses on the main terrifying or traumatizing event — the central details, which can remain vivid in memory. Other less important details, called peripheral details, may not be as well retained in memory.

Here's why.

The memory process involves these stages:

• Encoding — adding and embedding information into your memory
• Storage — retaining the encoded information in your memory
• Retrieval — accessing and recalling information when needed

In sexual assault survivors, the main traumatizing event typically becomes encoded in their memory, where it's stored and then later can be recalled. Some people also experience ruminations or flashbacks about their sexual assault — involuntary recurring thoughts and images of the traumatizing situation. Other peripheral details, such as location or date, may not be as well encoded, so they're not stored in the memory and aren't able to be recalled later.

The bottom line: People who are sexually assaulted more often remember the main traumatizing encounter itself across time because the attack is embedded in their memory. But other details or specific facts about that experience may not be as well encoded in memory, so that information can be very difficult and sometimes impossible to accurately recall years later.