The Constructive Nature of Memory • 215Source monitoring is the process of determining the origins of our memories, knowl-
edge, or beliefs (Johnson et al., 1993). In the conversation above, one person identi-
fi ed the evening news as his source of information about the movie; the other person
seemed unsure of his source, thinking it was either Bernita or Susan. If he thought it was
Bernita, but it turned out to be Susan, he would be committing a source monitoring error—
misidentifying the source of a memory. Source monitoring errors are also called source
misattributions because the memory is attributed to the wrong source. Source monitor-
ing provides an example of the constructive nature of memory because when we remem-
ber something, we usually retrieve the memory fi rst (“I heard about the scene at the
Harry Potter movie”) and then use a decision process to determine where that memory
came from (“It was either Bernita or Susan, because I talked to them recently. But it’s
more likely to be Bernita, because I know she really likes Harry Potter”) (Mitchell &
Johnson, 2000).
Source monitoring errors are common, and we are often unaware of them (as was
probably the case for Bartlett’s participants). Perhaps you have had the experience of
remembering that one person told you about something, but later realized you had
heard it from someone else—or the experience of claiming you had said something you
had only thought (“I’ll be home late for dinner”) (Henkel, 2004). President Ronald
Regan famously related a story about a heroic act by a U.S. pilot, only to have it
revealed later that his story was almost identical to a scene from a 1940s war movie, A
Wing and a Prayer (Johnson, 2006; Rogin, 1987). Apparently the source of the presi-
dent’s memory was the fi lm rather than an actual event.
Some of the more sensational examples of source monitoring errors are cases
of cryptomnesia, unconscious plagiarism of the work of others. For example, Beatle
George Harrison was sued for appropriating the melody from the song He’s So Fine
(originally recorded by the 1960s group The Chiffons) for his song My Sweet Lord.
Although Harrison had used the tune unconsciously, he was successfully sued by the
publisher of the original song. Harrison’s problem was that he thought he was the
source of the melody, when the actual source was someone else.
Source monitoring errors are important because the mechanisms responsible
for them are also involved in creating memories in general. Marcia Johnson (2006)
describes memory as a process that makes use of a number of types of information. The
primary source of information for memory is information from the actual event, includ-
ing perceptual experiences, emotions, and thoughts that were occurring at the time.
Additional sources of information that infl uence memory include people’s knowledge
of the world, and things that happened before or after the event that might become
confused with the event.
Later in the chapter we will describe a number of experiments that illustrate how
what people know about the world can cause them to misremember material presented
earlier. We will also describe experiments in which experimenters provide misleading
information after an event that causes participants to make errors when attempting to
remember the event. Source monitoring is a factor in these situations because partici-
pants are using this additional information, rather than information provided by the
actual event, as a source for their memory. We will now describe two experiments that
provide examples of how source monitoring errors can infl uence a person’s memory.The “Becoming Famous Overnight” Experiment: Source Monitoring and Familiarity
An experiment by Larry Jacoby and coworkers (1989) demonstrates an effect of source
monitoring errors by testing participants’ ability to distinguish between famous and non-
famous names. In the acquisition part of the experiment, Jacoby had participants read
a number of made-up nonfamous names like Sebastian Weissdorf and Valerie Marsh
(● Figure 8.10). In the immediate test, which was presented right after the participants
saw the list of nonfamous names, participants were told to pick out the names of famous
people from a list containing (1) the nonfamous names they had just seen, (2) new non-
famous names that they had never seen before, and (3) famous names, like Minnie Pearl
(a country singer) or Roger Bannister (the fi rst person to run a 4-minute mile), that many
people might have recognized in 1988, when the experiment was done. Just before thisCopyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.