218 • CHAPTER 8 Everyday Memory and Memory Errors
How do your answers from the fi ll-in-the-blank exercise on page 237 compare to
the words in the sentences that you originally read above? William Brewer (1977) and
Kathleen McDermott and Jason Chan (2006) presented participants with a similar
task, involving many sentences, and found that errors occurred for about a third of the
sentences. For the sentences above, the most common errors were as follows: (1) van-
ished became melted; (2) weakened became collapsed; (3) didn’t have became lost; (4)
hit became broke or smashed; and (5) stayed awake became cried.
These wording changes illustrate a process called pragmatic inference, which
occurs when reading a sentence leads a person to expect something that is not explicitly
stated or necessarily implied by the sentence (Brewer, 1977). These inferences are based
on knowledge gained through experience. Thus, although reading that a baby stayed
awake all night does not include any information about crying, knowledge about babies
might lead a person to infer that the baby was crying (Chan & McDermott, 2006).
In a classic experiment that demonstrated how inference can affect memory, John
Bransford and Marcia Johnson (1973) had participants read a number of action state-
ments in the acquisition part of the experiment and then tested their memory for the
statements later. Statement 1 below is one of the action statements that was read during
acquisition by participants in the experimental group, and Statement 2 is one of the
action statements read by participants in the control group (● Figure 8.13).- Experimental Group: John was trying to fix the birdhouse. He was pounding the
nail when his father came out to watch him and help him do the work. - Control Group: John was trying to fix the birdhouse. He was looking for the nail
when his father came out to watch him and help him do the work.
Both groups were then tested by presenting a number of statements that they had
not seen and asking them to indicate whether they had seen them before. Statement 3
below is a test statement that went with Statements 1 and 2. Notice that this statement
contains the word hammer, which did not appear in either of the original statements.- Experimental and Control Groups: John was using a hammer to fix the birdhouse
when his father came out to watch him and help him do the work.
Participants in the experimental group said they had previously seen 57 percent of
the test statements, but participants in the control group said they had previously seen
only 20 percent of the test statements (remember that in reality they hadn’t seen any
of the test statements). In the example above, participants in the experimental group,
who had read the sentence that mentioned pounding the nail, were more likely to be
misled into thinking that the original sentence had contained the word hammer thanRead “pounding
nails” sentence
and 5 others.57%AcquisitionExperimentalControlHave you seen
this sentence
(refers to “hammer”)
before?Read “looking for
the nail” sentence
and 5 others.20%Have you seen
this sentence
(refers to “hammer”)
before?TestResult
(percent of sentences erroneously
identified as seen before)●FIGURE 8.13
Design and results of
Bransford and Johnson’s
(1973) experiment that
tested people’s memory
for the wording of
action statements.
More errors were made
by participants in the
experimental group,
who identifi ed more
sentences as being
originally presented
even though they
were not.Copyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.