Pieces of Memory: PTSD Trauma and Flashbacks

PTSD trauma and flashbacks are serious issues nationwide, and not only for veterans. I sometimes have people ask me, “Hey, Meghan, how did you come up with that weird trauma response in Recall? Can people really lose parts of their memory but not others?”

Uhhhh…YES. They definitely can. Sometimes the brain even fills in missing information with things that may or may not be true, but that’s another article in itself. I’ve explored traumatic response in-depth through my characters, notably in Ash Park, Shadow’s Keep, and The Flood.

This post is an exploration of why memories fragment, how they become integrated, and the story of a man who fought flashbacks for sixty years before his repressed memories returned.

“John D.”

*Reasonable steps have been taken to disguise “John’s” identity in order to protect confidentiality.

John D. was a widowed elderly gentleman who was admitted to our locked inpatient unit by a colleague following the death of his eldest son. A veteran, John suffered what appeared to be constant auditory hallucinations. These voices had kept him up at night ever since the war, though he had refused assistance for them until after the passing of his wife and child.

“I just want the voices to stop,” he said. “The hallucinations make me crazy. I can’t calm down while they’re talking to me.”

But they were not hallucinations. John was suffering from Post-traumatic stress disorder, complete with fragmented memories and flashbacks that he had been unable to integrate into his experience for the last sixty years.

What had occurred in his brain that made this situation possible? How does PTSD change memory?

What is Post-Traumatic Stress Disorder (PTSD)?

Post-Traumatic Stress Disorder (PTSD) is usually diagnosed based on three categories of criteria:

1. Avoidance symptoms including staying away from places or things that remind you of the experience, feeling numb, having guilt, anxiety or worry, or a loss of interest in things you used to enjoy. Detective Petrosky experiences this acutely in Hidden.

2. Hyperarousal symptoms such as being easily startled, feeling tense or being quick to anger (these are often persistent throughout the day). (See Hannah in Famished.)

3. Re-experiencing symptoms such as flashbacks, scary thoughts and nightmares (like Cassie in Shadow’s Keep).

You might think that to have those “re-experiencing” symptoms, you have to actually recall the event in question, but this is not the case. Instead, we may recall bits and pieces of an event but without a narrative that makes sense to us. In John’s case, he was re-experiencing voices, though he could never understand what they were saying. To him, they were gibberish. But as we’d come to find out later, those voices did make sense. They were just speaking a language that he did not.

So, how to determine where those voices were coming from? What could trigger someone to recall voices alone but without any other information about where they heard them in the first place?

The Hippocampus and Memory Changes During Trauma

The hippocampus is responsible for encoding explicit memory, or taking information and putting it into a readily available form for later use. It essentially assigns a narrative that goes with the memories of events–a story to explain what occurred.

When you hear someone talking to you, your brain encodes: “Mary told me that these shoes are ugly.” (That cow!) You have a memory of the voice, the context of the statement itself, as well as a recollection of the shoes you were talking about.

In trauma, this explicit memory function is often blocked. When an individual is under excessive stress, the fight, flight or freeze response kicks into high gear and floods the body and brain with cortisol. In addition to giving the body extra energy to get away from a predator, cortisol also blocks functioning in the hippocampus, which alters the formation of explicit memory. According to psychiatrist Daniel Siegel, author of Mindsight, this is a type of chemically induced dissociation or cognitive blackout, where individuals have trouble integrating their memories into understandable forms.

Instead of remembering all the information that would allow a memory to make logical sense, during traumatic events, the brain favors implicit memory for the purposes of self-preservation. Implicit memories, such as those formed during pre-language learning, aren’t encoded in the hippocampus but are instead stored as sensations, such as sounds, tastes or physical pain, but without a story attached to them. Those higher levels of adrenaline in trauma also ensure that implicit memories—like the sound of voices or feelings of intense fear—are recalled at higher rates by making immediate connections to the amygdala, without the burden of conscious thought. Cognition—and understanding why you feel the way you do—is overrated when the goal is to leap to attention and flee. Why bother wasting all that energy on memory if you won’t be alive long enough to use it?

If Mary made the above statement during a traumatic event, you may recall only a vision of the shoes without any idea why they were important, or the sound of Mary’s voice on repeat without any other details, either of which may be attached to the panic response due to that immediate amygdala connection. In a slightly more likely scenario, you might go into full fight/flight/freeze mode whenever you hear a dog bark, or feel a pain in your leg when you smell a dog, all without having any memory of being bitten as a child.

For some, snippets of information get encoded, like John’s voices that went on repeat inside the head. For others, clear pictures of insignificant surrounding details emerge, such as the way a tree blew in the wind as you ran from the dog, or how blue the sky was. This type of dissociation is useful self-distraction, a method of reducing our awareness of painful or otherwise traumatic events. But those memories of a blue sky or a gentle breeze may come to be associated with anxiety in the future without integrating those memories into explicit form.

So how does the brain integrate information?

Memory Integration and Rapid Eye Movement (REM) Sleep

According to Siegel, nightmares and trouble sleeping are common in PTSD because the brain is trying to find ways to integrate those events into awareness. The brain does this fragments at a time to avoid overwhelming you, either with pieces of the memory it wants to transfer during the day in flashback form, or remembrances during sleep. Siegel refers to this as “consolidation,” the process of transferring implicit memories into explicit, understandable memories in the cortex. And Siegel believes that the chemical changes present in PTSD might alter REM sleep patterns, making it more likely that those traumatic memories will remain fragmented and implicit until the sleeping patterns needed to fully integrate them are restored.

In some cases, even after sleep returns, symptoms remain. In John’s case, he had never felt safe enough to let those memories flood back, partly because he was afraid others in his family would think he was “crazy.” In addition, integrating experiences–or forcing one to remember–can be painful, leading most to fight against it, just as John did for sixty years.

Towards Integration

John remembered a great deal about the war and the events surrounding it, but the voices were more anxiety producing than all his time spent on the battlefield. The voices became the focus of treatment. But it wasn’t until he spoke them aloud that it became clear they were real words. This was a shock to John, who had always insisted they were nonsense.

John’s “gibberish hallucinations,” as he called them, were a series of conversations in a different language that he did not speak–very normal everyday conversations about coffee, or lunch plans. The translations were just as boring as they sound:

“The coffee is too bitter.”

“I think it will be nice today.”

John reported fighting against the “enemy,” but never had casual contact or conversations with them. So when would John have been exposed to conversations of this type? Was he ever in a position to overhear them without interacting himself?

It was this that broke the walls. Within the safe space of our inpatient unit, sixty years after the event, John recalled that one morning, he and his best friend found themselves in the midst of an invasion by enemy soldiers. Too late to run, the men hid under bails of hay along the road, but being hidden did not protect them. The soldiers speared the hay as they walked by–they missed John. His friend died. The soldiers stayed in the area for several more days before moving on. During this time, John lay still under the hay, holding his best friend’s cold hand, waiting for them to kill him too.

It was a profound experience for John, the ability to finally recall these events and explain them in a way that made sense. For John, it was, “a sincere relief to not be crazy.” Once those memories were able to flood back, he could integrate them into his awareness. The voices stopped, as did his excessive anxiety and other PTSD symptoms.

While most cases are not quite as dramatic in scope, every person has the ability to integrate important puzzle pieces into their memories. For some, the process moves quickly. For others, it takes a bit longer for them to be fully ready to embrace what those memories might be. In any case, working with a therapist can be a great help in bringing past memories into awareness.

Memory integration is not an easy thing to accomplish, but it can be done. It’s just not something to tackle alone.