Do you remember where you were and what you were doing when a famous person died?  Or when a natural disaster happened somewhere on the globe?  Do you remember your first day of school? Or your first date? Some events are not easily forgotten. Why do we so clearly remember some events and forget others? The key appears to be that we remember better those experiences that involve emotions. Emotions are rich and diverse, and they are often what make the experience something special.

Research seems to show that emotions play a key role in how memory is formed.  But as you will also see, it may not be that emotional memories are special, it is just that we think that they are. And that feeling that our memories are "special" may lead us to believe that they are more accurate than they actually are.

Flashbulb memory theory

The theory of Flashbulb memory was first proposed by Brown & Kulik (1977). They defined flashbulb memory as a highly detailed, exceptionally vivid "snapshot" of the moment when a surprising and emotionally arousing event happened. They postulated the special-mechanism hypothesis, which argues for the existence of a special biological memory mechanism that, when triggered by an event exceeding critical levels of surprise, creates a permanent record of the details and circumstances surrounding the experience. This implies that flashbulb memories have different characteristics than "ordinary memories." They also argued that the memories are resistant to forgetting.

Brown and Kulik suggested that there may be a special neural mechanism that triggers emotional arousal because the event is unexpected or extremely important. At the time, it was only a hypothesis, but it is supported by modern neuroscience: emotional events are better remembered than less emotional events—perhaps because of the critical role of the amygdala. Today the most commonly accepted model of flashbulb memory is called the importance-driven model. This model emphasizes that personal consequences determine the intensity of emotional reactions.

Biological support for flashbulb memory

The original theory by Brown & Kulik was rather vague about the "biological mechanism" that plays a role. More recent research has found that the amygdala, a small structure in the temporal lobe, appears to be critical in the brain’s emotional circuit - and it is believed to play a critical role in emotional memories.

It makes sense that our brains would make sure to store information about fearful experiences in good detail.

When we are stressed, afraid, or surprised, we get a rush of adrenaline.  In evolutionary terms, the brain's ability to remember fear has most likely played a key role in our survival. Research by Cahill and McGaugh (1995)(see the biological approach - hormones) found that not only did participants remember the details when they had an emotional response to a story, but they remembered less when they had an emotional response but adrenaline levels were artificially suppressed.

Sharot et al (2007) carried out a study after the 9-11 attacks on the United States to determine the potential role of biological factors on flashbulb memories. The study was conducted three years after the 9/11 terrorist attacks in Manhattan. There were 24 participants who were in New York City on that day. Participants’ brain activity was observed using functional magnetic resonance imaging (fMRI).

While in the scanner, they were presented with word cues on a screen.  In addition, the word "Summer" or "September" was projected along with this word in order to have the participant link the word to either summer holidays or to the events of 9-11. Participants’ brain activity was observed while they recalled the event.

After the brain scanning session, participants were asked to rate their memories for vividness, detail, confidence in accuracy, and arousal. Participants were also asked to write down their personal memories. Only half of the participants actually reported having what would be called "flashbulb memories" of the event - that is, a greater sense of detail and strong confidence in the accuracy of the memory. Those that did report having flashbulb memories also reported that they were closer to the World Trade Centre on the day of the terrorist attack. Participants closer to the World Trade Centre also included more specific details in their written memories. 

Sharot and her team found that the activation of the amygdala for the participants who were downtown was higher when they recalled memories of the terrorist attack than when they recalled events from the preceding summer, whereas those participants who were further away from the event had equal levels of response in the amygdala when recalling both events. The strength of amygdala activation at retrieval was shown to correlate with flashbulb memories. These results suggest that close personal experience may be critical in engaging the neural mechanisms that produce the vivid memories characteristic of flashbulb memory.

Although this study demonstrates the role of the amygdala as a result of proximity to the event, it does not explain why someone who simply saw it on television may claim to have a flashbulb memory. The study is correlational in nature and does not establish a cause and effect relationship which explains how the memory is actually attributed to activity in the amygdala.

Criticism of flashbulb memory theory

Neisser (1982) has questioned the idea of flashbulb memories. People do not always know that an event is important until later, so it is unclear how flashbulb memories could be created at the moment of the event. He suggests that the memories are so vivid because the event itself is rehearsed and reconsidered after the event. According to Neisser, what is called a flashbulb memory may simply be a well-rehearsed story. The flashbulb memories are governed by a storytelling schema following a specific structure, such as place (where were we?), activity (what were we doing?), informant (who told us?), and affect (how do we feel about it?).

On 28 January 1986, the seven astronauts aboard the Space Shuttle Challenger were killed in a tragic accident. It was a shocking experience for those who watched the shuttle launch in person or on television. Neisser and Harsch (1992) investigated students’ memory accuracy of the incident 24 hours after the accident, and then again two and a half years later. When filling out the second questionnaire which asked questions like - where were you when you heard about the Challenger disaster?  Who were you with? What were you doing?  The participants were also asked how confident they were of these memories.

The participants were very confident that their memories were correct, but the researchers found that 40 percent of the participants had distorted memories in the final reports they made. Possibly, post-event information had influenced their memories. The researchers concluded that emotional intensity was associated with greater memory confidence, but not with accuracy.

Cultural dimensions also seem to play a role in flashbulb memories. Kulkofsky et al (2011) looked at the role of culture in flashbulb memory in five cultures: China, Germany, Turkey, the UK, and the USA. Participants were given five minutes to recall as many memories as they could of public events occurring in their lifetime. They were then asked to complete a "memory questionnaire" for each event where they were asked if they remembered where they first heard of the event. If so, then they were asked a series of questions to determine the extent of the FBM. They were then asked to answer questions about the importance of the event to them personally.

The researchers found that in a collectivistic culture like China, personal importance and intensity of emotion played less of a role in predicting FBM, compared with more individualistic cultures that place greater emphasis on an individual's personal involvement and emotional experiences. Because focusing on the individual's own experiences is often de-emphasized in the Chinese context, there would be less rehearsal of the triggering event compared with participants from other cultures - and thus a lower chance of developing an FBM. However, it was found that national importance was equally linked to FBM formation across cultures.