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Traumatic Flashbacks: A Hypothesis

20 May, 2013
traumatic flashbacks are an adaptation

Traumatic flashbacks are not psychological "damage".

Traumatic flashbacks are your brain's way of saying: "Make sure it never happens again".


Traumatic flashbacks are where a person has suffered some traumatic event, and that person repeatedly suffers involuntary recall of the event, and the recall episodes include some or all of the distress and suffering of the original trauma.

Traumatic flashbacks are a component of Post-Traumatic Stress Disorder.

"Damage", or Adaptation?

A common narrative about traumatic flashbacks is that a person who experiences a traumatic event has been psychologically "damaged" by the trauma, and that a "healing" or "recovery" processs is required which will make the distressing flashbacks disappear, or at least reduce in intensity.

Now it is true that a traumatic event may include physical damage to the person who experiences it, but the narrative here is that the person's mind has been damaged by the intensity of the traumatic experience, and not as a result of physical brain damage.

It seems plausible that the very intensity of a traumatic experience could "damage" a mind, on the assumption that the intensity is greater than what the brain is designed to handle, due to the extreme nature of the traumatic event.

The problem with this explanation is that the kinds of traumatic events that cause flashbacks may lie outside the life experience of a typical person, especially those of us who live in modern "safe" and "civilised" societies, but those traumatic events are well within the boundaries of human experience on an evolutionary timescale.

Some traumas that give rise to flashbacks involve a victim who has been physically attacked, others arise from what are purely accidents or natural disasters.

But people have been attacking and killing and raping each other, and also suffering accidents and natural disasters, throughout all of human history and all of human prehistory. Furthermore, how one deals with such things is often critical to one's long term survival.

So it is very likely that the human brain is highly adapted to deal with trauma.

In which case, the notion that trauma damages the brain is simply wrong. The brain's response to trauma is not that of damage, rather it is how a person's brain processes information about a trauma, so as to optimise their future long-term reproductive success.

Flashbacks as Information Processing

So, what do flashbacks achieve? Why must a person who has suffered a traumatic event be punished, not just once by the original bad thing that happened to them, but over and over again?

Hypothesis: Do Everything Possible to Make Sure It Doesn't Ever Happen Again

If we consider the response to a traumatic event as an information processing problem, which is to be solved by some type of calculation, there are two major calculations required:

  1. How much actual damage has been done to the person by the traumatic event, and what should be done to alleviate it?
  2. What can the person do to prevent, as much as possible, any re-occurrence of the traumatic event?

Flashbacks are plausibly more related to the second calculation, and they also relate to the unexpectedness of a traumatic event.

That is, if the person had already been expecting the traumatic event, then, in most cases, that person would have done something to prevent it. It follows that the occurrence of an unexpected traumatic event is proof of a failure to predict the possibility of such an event. This implies a requirement for the person to realign their expectations with the newly observed reality and to decide how to change future behaviours in the light of these updated expectations.

The more unexpected and severe the trauma, the more the person's expectations will have to change, and consequently the more they will have to change their future behaviour.

It would be all too easy to ignore the need for such changes, to just accept the damage caused by the traumatic event, to hope that it is just a one-off that will never happen again, and to otherwise continue living as if nothing much had happened.

But evolution has decided for us, whether we like it or not, that just ignoring the occurrence of unexpected bad things is not a recipe for long-term reproductive success.

It may be, that some traumatic events are just one-off experiences, and in any particular case, if one could be sure of that, there would be no reason to re-adjust one's life strategies to take them into account.

But nothing in life can be known with that degree of certainty, and on average, over the history of the human species, unexpected bad things are not one-offs. Rather, they are evidence of previously unknown or under-estimated dangers, and they are an indication that people who have suffered and experienced those events should think hard about to deal with the risk that those events might happen again.

The only information that the brain has about an unexpected traumatic event is the very memory of the event itself. The only way to present this information to the conscious brain is to forcibly "relive" the event, from memory. Which is what flashbacks are.

And the only way to include information about the urgency of re-adjusting expectations and behavioural strategies is to include the original negative emotions of the trauma into the flashbacks. Which is why the flashbacks have to be as unpleasant (or nearly so) as the original event.

How to "Cure" Flashbacks

One way to "cure" unpleasant feelings is to directly suppress the body's sensory mechanisms.

If a surgeon needs to operate on your foot, then anaesthetic will be applied to dull or eliminate the pain. There is nothing that you can do to fix whatever is wrong with your foot, and your reaction to the pain of surgery would only interfere with the surgeon's efforts to do the surgery (it would also discourage you from seeking surgery in the first place).

But if your foot hurts because someone is standing on your foot, it doesn't make sense to reach for the pain-killers. It makes sense to realise that the pain is caused by something heavy being on your foot, and then do something to get that thing off your foot (like saying "Excuse me but I think you're standing on my foot.").

Something similar applies to traumatic flashbacks. There may be situations where it makes sense to directly "treat" flashbacks by taking a "flashback-killing" drug (if and when science discovers such a drug). Especially if we can determine that a person's flashbacks are caused by a reaction to an extreme unlucky "one-off" event, in which case there is little reason for the person to waste significant effort trying to re-adjust their life to avoid a second very unlikely re-occurrence of the same event.

But before we consider medical interventions, we should allow for the possibility that flashbacks are actually a good thing, which guide us on how to live a better and more successful (and safer) life. We should seek to understand how we can speed up the re-adjustment process which flashbacks are "designed" (in an evolutionary sense) to encourage.

Within this understanding of traumatic flashbacks as an adaptation, the following is a plausible strategy for speeding up the process of re-adjustment:

Flashbacks and "Blame"

A common response to a trauma, especially when it happens to a loved one of yours, but even when it happens to yourself, is the feeling that "I am to blame". This feeling can be very strong, even if a rational analysis of the situation would suggest that you weren't to blame.

We can understand this as resulting from the extreme urgency of prevention of future re-occurrences. It is not so much that you must have been at fault, but rather that all possibilities should be considered. If there is even the possibility that you were to blame, then this should be considered, and only be abandoned when the possibility has been considered thoroughly and no evidence has been found that you were to blame.

The notion of "blame" can be rather fuzzy. If you get mugged walking along the street, you weren't legally to blame, and you weren't morally to blame. But if at the time you were listening to music on your iPod, with your eyes shut, then that might have had something to do with why you got mugged. In a purely pragmatic sense, you could be held to "blame" for allowing yourself to be more vulnerable to an attack. And you might decide in future not to listen to music through earphones when you're out on the street.

"Re-adjustment" and "Normal" Life

A big question about "re-adjustment" is: Will I be forced to re-adjust so much that I can no longer live my normal life?

This is a non-trivial question. Someone who has been mugged may be afraid to ever go outside. A woman who has been raped may avoid all strange men. Or even all men.

There is no easy answer to this question. Some of the re-adjustments that you propose to yourself during a flashback may not survive real life. And rethinking those re-adjustments may itself trigger new flashbacks, because by abandoning a planned preventative measure, you are re-creating the risk of a re-occurrence. These new flashbacks will have the effect of forcing you to think of alternative re-adjustments, given that it turns out that you were not serious about applying the first set of re-adjustments that you thought of.

Also, no danger can ever be fully eliminated. Even before we experience some traumatic event, we know that life has its dangers, and we tolerate some level of constant danger as part of living our normal lives. The final result of a "re-adjustment" process won't be an elimination of danger, it will be a reduction of perceived risk as a result of decisions made to change how you deal with that risk, such that the perceived risk is tolerable, and not too different from all the other risks that exist anyway.

So the rape victim will not avoid all men, but she might be much more careful about which men she deals with, and she might become more aware of situations where she risks losing control or being trapped, and she might go to some self-defense courses. And even after making those changes, she will probably never feel as relaxed with men as a woman who has never been raped, and given the severe trauma that a rape is, it may take a long time (if ever) for flashbacks to completely disappear.

Additional Evidence for this Hypothesis

Flashbacks often occur as a result of extreme traumatic events involving physical assault or injury to the victim.

Minor Traumatic Flashbacks

But flashbacks also occur with relatively minor traumas, where perhaps a significant loss has occurred unexpectedly, but not necessarily as severe as death or rape or permanent bodily harm.

Like many people, I have never suffered any truly major trauma. But my experience of minor traumas, and associated flashbacks, is consistent with the theory I have described here – in particular the suggested strategy for "curing" flashbacks seems to work reasonably well.

When flashbacks happen, I do not attempt to avoid them or suppress them. I just allow them to happen, and suffer them, knowing that they are something that has to happen (I won't say "suffer gladly", because the experience is never pleasant). And for any particular "trauma" that I may be getting flashbacks on, they do eventually stop happening.

Traumas Where Someone Else is the "Victim"

Flashblacks can occur in situations where a person experiences a traumatic event in which someone else has been harmed. In this case the flashback sufferer's loss is not that they have been injured, but that the other person has been injured.

This can be traumatic for one of two reasons: either the actual victim is someone that the person is emotionally attached to, or, the person suffers flashbacks because will be held responsible (or at least they will feel responsible) for their actions in causing or not preventing harm to the actual victim. Or both of those reasons – a person's loved one got hurt and it was that person's fault. In either case, we can understand that the purpose of the flashbacks is to force the person to rethink their intentions and actions so that in the future they can prevent (or not cause) harm to another person.

Near Misses

Flashbacks also occur as a result of near misses, where something bad could have happened, but actually didn't. Here it also makes sense that flashbacks are a preventative mechanism, in this case to prevent something happening in the future that didn't actually happen the first time (but it could have).

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