Flashbulb memories and the reminiscence bump
One interesting feature of memory is that people seem to be able to remember certain events very vividly for a long time, especially if they are particularly unusual and arousing. Two different aspects of this phenomenon are i) flashbulb memories and ii) the reminiscence bump.
The assassination of John F. Kennedy in 1963, the death of Princess Diana in 1997, and the destruction of the Word Trade Centre in New York in 2001 are very memorable events for people who were alive when these events occurred. Memory for such events appears to be very resistant to forgetting over time. Many people are able to remember where they were and who
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they were with when they heard the news of one or all of these events. This is an example of what has been termed flashbulb memory. In highly arousing situations such as these, people often seem to remember well. This phenomenon may well
be related to pressures operating during our evolutionary past. As stated by Shakespeare in Henry V when making reference to the Battle of Agincourt: ‘Old men forget: yet all shall be forgot, But he’ll remember with advantages what feats he did that day.’
By comparison, the reminiscence bump occurs when people are asked during later life to remember events from across their lifespan. In these situations, people tend to remember disproportionately more events from the period between their adolescence and early adulthood. This point was neatly encapsulated by the writer and lawyer John Mortimer when he stated that: ‘The distant past, when I was acting my solo version of Hamlet before the blind eyes of my father, duelling with myself and drinking my own poisoned chalice . . . seems as clear as yesterday. What are lost in the mists of vanishing memory are
the events of ten years ago.’ It has been suggested that this reminiscence bump is due to the particular significance of events that are occurring during the earlier portion of one’s life. These are frequently events in which emotions are heavily involved (a consideration that may also be relevant for flashbulb memories). Such events include: meeting one’s partner, getting married or becoming a parent — and events that are significant in other ways, such as starting work, graduating from university or backpacking around the world.
The areas of flashbulb memories and the reminiscence bump are both quite controversial; for example, with respect to flashbulb memories, it has been questioned to what extent semantic memory may intrude upon episodic memory for events such as the death of Princess Diana (such that we feel that we are remembering
episodic detail richly, when in fact much of this detail may be inferred — refer to Chapter 2 for a brief consideration of the extent to which semantic and episodic memory may interact, and to Chapter 1 regarding the degree to which ‘top down’ influences may be relevant in memory). Nevertheless, both of these topics are the subjects of considerable interest in the memory literature.
Organization and errors in memory
The palest ink is better than the best memory.
In the 1960s and 1970s, some studies were carried out on chess players to find out how well they could remember the positions of chess pieces on a board. The studies showed that chess masters could remember 95% of the pieces on the chessboard after a single 5-second glance. But weaker chess players were able to position only 40% of the pieces correctly, and needed eight attempts to reach 95% correct performance. Examined in more detail, the findings suggested that the advantage enjoyed by the chess masters stemmed from their ability to perceive the chessboard as an organized whole, rather than as a collection of individual pieces. Similar effects have been shown with expert bridge players when they attempt to recall bridge hands, or where electronics experts are asked to remember electronic circuits. In each case, it appears that the experts organize the material into a coherent and meaningful pattern. Drawing on a rich background of prior experience, experts seem to be able to enhance their memory performance significantly above that of non-experts.
We have already seen in Chapter 3 that organizing information at the time of retrieval (in the form of cueing) can aid recall, but these studies of experts reveal the benefits of organization at the time of learning too. In the laboratory, researchers have compared memory for the learning of a) relatively unstructured material with the recall of b) material that had some structure imposed at
episodic detail richly, when in fact much of this detail may be inferred — refer to Chapter 2 for a brief consideration of the extent to which semantic and episodic memory may interact, and to Chapter 1 regarding the degree to which ‘top down’ influences may be relevant in memory). Nevertheless, both of these topics are the subjects of considerable interest in the memory literature.
Organization and errors in memory
The palest ink is better than the best memory.
In the 1960s and 1970s, some studies were carried out on chess players to find out how well they could remember the positions of chess pieces on a board. The studies showed that chess masters could remember 95% of the pieces on the chessboard after a single 5-second glance. But weaker chess players were able to position only 40% of the pieces correctly, and needed eight attempts to reach 95% correct performance. Examined in more detail, the findings suggested that the advantage enjoyed by the chess masters stemmed from their ability to perceive the chessboard as an organized whole, rather than as a collection of individual pieces. Similar effects have been shown with expert bridge players when they attempt to recall bridge hands, or where electronics experts are asked to remember electronic circuits. In each case, it appears that the experts organize the material into a coherent and meaningful pattern. Drawing on a rich background of prior experience, experts seem to be able to enhance their memory performance significantly above that of non-experts.
We have already seen in Chapter 3 that organizing information at the time of retrieval (in the form of cueing) can aid recall, but these studies of experts reveal the benefits of organization at the time of learning too. In the laboratory, researchers have compared memory for the learning of a) relatively unstructured material with the recall of b) material that had some structure imposed at
episodic detail richly, when in fact much of this detail may be inferred — refer to Chapter 2 for a brief consideration of the extent to which semantic and episodic memory may interact, and to Chapter 1 regarding the degree to which ‘top down’ influences may be relevant in memory). Nevertheless, both of these topics are the subjects of considerable interest in the memory literature.
Organization and errors in memory
The palest ink is better than the best memory.
In the 1960s and 1970s, some studies were carried out on chess players to find out how well they could remember the positions of chess pieces on a board. The studies showed that chess masters could remember 95% of the pieces on the chessboard after a single 5-second glance. But weaker chess players were able to position only 40% of the pieces correctly, and needed eight attempts to reach 95% correct performance. Examined in more detail, the findings suggested that the advantage enjoyed by the chess masters stemmed from their ability to perceive the chessboard as an organized whole, rather than as a collection of individual pieces. Similar effects have been shown with expert bridge players when they attempt to recall bridge hands, or where electronics experts are asked to remember electronic circuits. In each case, it appears that the experts organize the material into a coherent and meaningful pattern. Drawing on a rich background of prior experience, experts seem to be able to enhance their memory performance significantly above that of non-experts.
We have already seen in Chapter 3 that organizing information at the time of retrieval (in the form of cueing) can aid recall, but these studies of experts reveal the benefits of organization at the time of learning too. In the laboratory, researchers have compared memory for the learning of a) relatively unstructured material with the recall of b) material that had some structure imposed at
How does knowledge promote remembering?
As was indicated in Chapter 3, experts in any area find it easier and quicker to learn new information within their expertise than do novices. This finding indicates that what we learn appears to depend heavily on our existing knowledge. For example, Morris and colleagues showed that there was a very strong relationship between how much their participants knew about football and the number of new football scores they could remember after hearing them just once. Participants were read a new set of football scores as they were being broadcast at the weekend. One set of football scores were the real scores, while another set of scores was simulated by constructing plausible pairs of teams and assigning goals with the same frequency as had occurred in an earlier week. Participants in the study were told whether the scores they heard were real or simulated. Only the real scores seemed to activate the knowledge and interest of the football experts. For real scores, level of memory recall was clearly related to football expertise — so more knowledgeable fans recalled more of the scores. But for simulated scores (where the scores were highly plausible but not the genuine results), it was found that expertise had relatively little effect on subsequent recall performance. These findings illustrate the interaction of memory capacity with existing knowledge (and, presumably, interest and motivation, too) in determining what is effectively remembered.
How can knowledge lead to errors?
Our previous knowledge is a very valuable asset, but it can also lead to errors. In one relevant study, Owens and colleagues gave their participants a description of the activities performed by a particular character. For example, one of the sketches was about a student named Nancy. Here is the first part of that sketch:
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Nancy went to the doctor. She arrived at the office and checked in with the receptionist. She went to see the nurse who went through the usual procedures. Then Nancy stepped on the scale and the nurse recorded her weight. The doctor entered the room and examined the results. He smiled at Nancy and said, ‘Well, it seems my expectations have been confirmed.’ When the examination was finished, Nancy left the office.
Half of the participants were told in advance that Nancy was worried that she was pregnant. These participants included between two and four times as many pieces of incorrect information when tested on their recall of the sketch. For example, some of them recalled the ‘usual procedures’ that were conducted as comprising ‘pregnancy tests’. These types of errors were made in both recognition and recall tests. These findings reflect the fact that people have many expectations about how conventional activities (going to the doctor, a lecture, a restaurant) will
proceed — and these expectations provide schemas that can either facilitate or mislead with respect to our memory functioning. In another part of their ‘washing clothes’ study, Bower and colleagues studied the influence of such schemas on subsequent recall. They gave their participants stories based on normal expectations, but the stories included significant variations from the norm. So, for example, a story about eating in a restaurant might refer to paying the bill at the beginning of the meal. When recalling the stories, participants tended to reorder their recall back to the schematic (i.e. more typical) form of the story. Other common errors that people made involved including actions that would normally be expected in that particular context, but which had not been mentioned in the original story — such as looking at the menu before selecting one’s meal.
In general, the findings of these and similar studies indicate that people tend to remember what is consistent with their schemas, but filter out what is inconsistent.
Real versus imagined memories
As was mentioned in Chapter 1, even when we believe that we are literally ‘playing back’ some previous event or information in our mind, as if it were a videotape, we are actually constructing a memory from bits and pieces that we actually remember, along with our general (i.e. semantic) knowledge about how these bits should be assembled.
This strategy is usually very adaptive, minimizing our need to remember new things that are very similar to things we already know. But sometimes there can be a blurring between what actually happened and what has been imagined or suggested.
Reality monitoring
The issue of reality monitoring — i.e. identifying which memories are of real events, and which are of dreams or other imaginary sources — has been systematically addressed over a number of years by Marcia Johnson and her colleagues. Johnson has argued that qualitative differences between memories are important for distinguishing external memories from internally generated ones. She contends that external memories i) have stronger sensory attributes, ii) are more detailed and complex, and iii) are set in a coherent context of time and place. By contrast, Johnson argues that internally generated memories embody more traces of the reasoning and imagining processes that generated them.
Although Johnson found support for these differences, applying these proposed distinctions as defining criteria can nevertheless lead to our accepting some memories as real, even when they
are not. For example, a study was conducted in the 1990s in which participants were required to recall details from a videotape, and to report both a) their confidence and b) the presence or absence of clear mental imagery and detail. Clear images and details were found to occur more often with correct reports of what had been presented on the videotape. However, the presence of accessible
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images led people to be overly confident, so that incorrect
details accompanied by mental images were reported with greater confidence than correct details that lacked these associated images. These findings seem to indicate there is no completely reliable way of distinguishing between ‘real’ and ‘imagined’ memories.
Related to the concept of reality monitoring is source monitoring — i.e. being able to successfully attribute the origin of our memories (e.g. being able to state that we heard a particular piece of information a) from a friend rather than b) hearing it on the radio). As we shall see, errors in attributing memories can have important consequences — for example, during eyewitness testimony (Mitchell and Johnson, 2000).
Eyewitness testimony
Even aspects of our everyday environment can be very poorly remembered. For instance, in Chapter 1 we saw that it can be challenging to remember correctly something as straightforward as whether the head on a coin in one’s pocket is pointing to the left or to the right. Generally speaking, people are very poor at answering this question, even when they use those particular coins almost every day. Some people might argue, though, that when we observe an unusual event (such as a crime), we are in a much better position to remember this effectively than when we are trying to remember the mundane features of a coin. After all, in our everyday lives we don’t need to know which way the head points in order to be able to use coins effectively.
However, in a crime situation, we know that many factors work against an eyewitness, and can obscure or distort his or her memory:
r Although enhanced arousal can facilitate memory (as we have seen earlier), when a person is experiencing extreme stress, their attention can be narrowed (for example, towards a potentially dangerous weapon) and perception is often biased.
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r Related to this last point, people tend to remember more poorly when they are in a violent situation — where self preservation is more the priority (for example, one may be allocating one’s cognitive resources towards finding an exit route, or finding an item with which one could defend oneself — rather than towards processing the appearance and identity of the perpetrator).
r Associated with the above, a weapon located at the scene of a crime can distract a person’s attention away from the perpetrator of the crime.
r Although we are much better at recognizing faces than recalling information, clothing is a particularly powerful source of bias in recognition — so an individual who happens to be wearing similar clothing to the culprit could be incorrectly ‘recognized’.
r People tend to be poorer at recognizing faces of individuals from different racial and ethnic groups to themselves — even when they have considerable experience of interacting with people from other races (furthermore, this phenomenon doesn’t seem to be related to degree of racial prejudice).
