Wednesday, September 26, 2012

you can't trust your brain: memory

"Flashbulb" memories are those vivid memories of specific salient events.  The 'everyone remembers exactly where they were when...' sort of events.  In the USA, and depending on how old you are, you might remember the assassination of JFK, or Martin Luther King Jr. in this way. In this century, most Americans remember exactly where they were when they heard about the 9/11 attacks on the world trade center and pentagon.
"Never Forget" (source)
It's widely acknowledged these days that the brain is not really a safe place to store information. Memories of events change over time. But for a while the "flashbulb" memory was thought to be immune from the memory-altering properties of time. Think about your own memories of 9/11 or another highly meaningful event. I bet you are pretty certain about the details. I, for example, was in my second year of college and I know exactly who told me that the first tower was hit, exactly where I was standing on the quad, and exactly what class I was going to....

...or do I? 

A study in 2003 tested the consistency of flashbulb memories over time and compared the details to 'control memories' of everyday events. They specifically recorded memories from people during the day after the 9/11 attacks, and then recorded memories of the same events from subsets of those same people 1 week, 6 weeks, and 32 weeks later. They found that the flashbulb memories did have different properties when compared to control memories, but that consistency was not one of them. 

Talarico and Rubin 2003, Figure 1a
Talarico and Rubin show that the flashbulb memories and the everyday memories had the same time-dependent decay (that x axis is in days), demonstrating that the flashbulb memory did not have some special property that protected it from corruption. 

However, they did find that the level of confidence in the memory was higher for flashbulb memories than for everyday memories. People thought (incorrectly) that their memories of the 9/11 attacks were more accurate than their other memories. 

So again we learn the lesson that we cannot trust ourselves.

In the authors words:
"The true 'mystery,' then, is not why flashbulb memories are so accurate for so long,... but why people are so confident in the accuracy of their flashbulb memories." Talarico and Rubin (2003)

But I think the most interesting finding in this paper was that the flashbulb memories of 9/11 were more likely to be recalled 'through ones own eyes' than the everyday memories. Everyday memories were seen 'through ones own eyes' at the beginning and a at 1 week, but at 6 and 32 weeks the everyday memories were more likely to be seen 'from an outside observer perspective.' The flashbulb memories, on the other hand, were seen 'through ones own eyes' at all time points. Indeed, when I think of my own 9/11 memory, I still see it through my own eyes.

The authors don't go into why that might be or what it might mean, so we are left to wonder.

© TheCellularScale
Talarico JM, & Rubin DC (2003). Confidence, not consistency, characterizes flashbulb memories. Psychological science, 14 (5), 455-61 PMID: 12930476


  1. The Hippocampus plays an important role in your ability to form new memories. So in this case the hippocampus is what makes people create new memories about their major experiences. By forming new memories the old, real ones get erased and the new ones formed by the hippocampus replace the others.

  2. I defintely agree with Dani^ about our hippocampus forming our new memories in our crazy yet interesting brain. But about the actual stage of our memory, which is called the Stage Model of Memory,the basic working of memory. First we have the sensory memory, which is when information is registered, and large capacity at that. Then, after is the short-term (working) memory, new information is transferred from sensory memory,and the old information is being retrieved, but in there its limited capacity. This could be the part would the things we once memory turns into something esle due to the limit in this particular stag. Last, is the Long-term memory, information that has been encoded in short-term memory is stored, and here's there's a unlimited capacity for information