10 - Why do traumatic experiences sometimes produce good memory (flashbulbs) and sometimes no memory (repression)?

Summary

“The past is a foreign country … they do things differently there.” So begins L. P. Hartley's classic book, The Go-Between (1953). In thinking about “flashbulb” memories, specifically about the match between their present character and the past experience that gave rise to them, it is tempting to ask a similarly phrased question: Did they do things differently there?

There is no doubt that present memories about past traumatic episodes persist in the minds of most of us. But were things different then (in reality) than they are now (in our minds)? It turns out that some aspects of traumatic experiences do apparently persist quite accurately, whereas other aspects get altered along the way. These persisting flashbulbs, dotted with error, raise a question about the kind of memory system that can accommodate both persistence and error. What functions would such a system serve, asks Pillemer (this volume)? Equally intriguing is why some traumatic events get transformed into persisting flashbulbs, whereas other traumatic events are entirely repressed in memory for long periods of life?

Persisting flashbulbs that resemble the past

Clearly, we remember details from the traumatic events of our past. We remember the circumstances in which we first learned about shocking public or private tragedies. Take the first major eruption of Mount Saint Helens, which occurred on May 18, 1980. This shocking public event was well known to residents of the northwestern United States.