Flashback (psychology) - Theoretical Accounts

Theoretical Accounts

Due to the elusive nature of involuntary recurrent memories, very little is known about the subjective experience of flashbacks. However, theorists agree that this phenomenon is in part due to the manner in which memories of specific events are initially encoded (or entered) into memory, the way in which the memory is organized, and also the way in which the individual later recalls the event. Overall, theories that attempt to explain the flashback phenomenon can be categorized into one of two viewpoints. The special mechanism view is clinically oriented in that it holds that involuntary memories are due to traumatic events, and the memories for these events can be attributed to a special memory mechanism. On the other hand, the basic mechanism view is more experimentally oriented in that it is based on memory research. This view holds that traumatic memories are bound by the same parameters as all other every-day memories. Both viewpoints agree that involuntary recurrent memories result from rare events that would not normally occur.

These rare events elicit strong emotional reactions from the individual since it violates normal expectations. According to the special mechanisms view, the event would lead to fragmented voluntary encoding into memory (meaning that only certain isolated parts of the event would be encoded), thus making the conscious subsequent retrieval of the memory much more difficult. On the other hand, involuntary recurrent memories are likely to become more available, and these are more likely to be triggered by external cues. In contrast to this, the basic mechanism view holds that the traumatic event would lead to enhanced and cohesive encoding of the event in memory, and this would make both voluntary and involuntary memories more available for subsequent recall.

What is currently an issue of controversy is the nature of the defining criteria that makes up an involuntary memory. Up until recently, researchers believed that involuntary memories were a result of traumatic incidents that the individual experienced at a specific time and place, but the temporal and spatial features of the event are lost during an involuntary recollection episode. In other words, people who suffer from flashbacks lose all sense of time and place, and they feel as if they are re-experiencing the event instead of just recalling a memory. This is consistent with the special mechanism viewpoint in that the involuntary (unintended) memory is based on a different memory mechanism than its voluntary (intended) counterpart. Furthermore, the initial emotions experienced at the time of encoding are also re-experienced during a flashback episode, and this can be especially distressing when the memory is of a traumatic event. It has also been demonstrated that the nature of the flashbacks experienced by an individual are static in that they retain an identical form upon each intrusion. This occurs even when the individual has learned new information that directly contradicts the information retained in the intrusive memory.

Upon further investigation, it was found that involuntary memories are usually derived from either stimuli (i.e. anything that causes a change in behaviour) that indicated the onset of a traumatic event, or from stimuli that hold intense emotional significance to the individual simply because these stimuli were closely associated with the trauma in terms of timing. These stimuli then become warning signals that if encountered again, serve to trigger a flashback. This has been termed the warning signal hypothesis. For example, a man experiences a flashback upon seeing sun spots on his lawn. This happens because he associates the sun spots with the headlights of the vehicle that he collided with, causing a horrific car accident. According to Ehlers and Clark, traumatic memories are more apt to induce flashbacks simply because of faulty encoding in that the individual fails to take contextual information into account, as well as time and place information that would usually be associated with every-day memories. These individuals become more sensitized to stimuli that they associate with the traumatic event which then serve as triggers for a flashback (even though the context surrounding the stimulus may be unrelated; such as sun spots being unrelated to headlights). These triggers may have elicited an adaptive response during the time of the traumatic experience, but they soon become maladaptive if the person continues to respond in the same way in situations in which no danger may be present.

The special mechanism viewpoint would add to this further by suggesting that these triggers activate the fragmented memory of the trauma, but protective cognitive mechanisms function to inhibit the recall of the original memory of the traumatic event. Dual representation theory enhances this idea by suggesting two separate mechanisms that account for voluntary and involuntary memories; the first of which is called the verbally accessible memory system and the latter is referred to the situationally accessible memory system.

In contrast to this, theories belonging to the basic mechanism viewpoint hold that there are no separate mechanisms that account for voluntary and involuntary memories. The recall of memories for stressful events do not differ under involuntary and voluntary recall. Instead, it is the retrieval mechanism that is different for each type of recall. In involuntary recall, the external trigger creates an uncontrolled spreading of activation in memory, whereas in voluntary recall, this activation is strictly controlled and is goal-oriented.