Jenkins, R., Lavie, N., & Driver, J. (2005). Recognition memory for distractor faces depends on attentional load at exposure. Psychonomic Bulletin & Review, 12, 314-320.
The present study sought evidence for Lavie’s “perceptual load” theory, which suggests that telling participants that a stimulus is “irrelevant” probably does not guarantee that they do not focus on that stimulus. Instead, to test attention, the stimuli should always be irrelevant and attentional load should be varied with other experiment-related tasks.
To test this idea, perceptual load of a nonface task was varied and subsequent recognition of “irrelevant” faces was analyzed in a surprise recognition task.
Experiment 1
Twelve participants studied word strings that were superimposed over black & white faces. In the low-load condition, participants had to indicate if the letters were red or blue. In the high-load condition, participants had to indicate if an X or an N was among a number of angular-shaped letters. The face & letter display was shown for 200 msec.
Results: Participants performed the “relevant task” better in the low-load condition than the high-load condition (so perceptual load was effectively manipulated). Furthermore, face recognition was significantly higher (at 50%) in the low-load faces versus the high-load faces and the foil faces.
Experiment 2
What if the results of experiment 1 were due to the differences in “task relevant” tasks? To test for this, 12 more participants were run. The high-load condition did the same task as before, and the low-load condition decided whether a string of 6 letters had an X or an N (although all six letters were the same).
Results: Participants were faster in the low-load condition. They were also much better at recognizing the faces from that condition (although in this experiment, the high-load condition was significantly higher than the foil false recognition).
Experiment 3
What if it is harder for the high-load people to keep the face in memory for an extended retention interval? This experiment had participants do either the low-load task or the high-load task from Experiment 2, but they only had a surprise recognition test for the final face of the series. That is, immediately following the final trial, they were presented with a two-alternative forced-choice test.
Results: Again, participants in the low-load task performed significantly faster than those in the high-load task. In addition, participants in the low-load condition recognized the face significantly more often than the high-load condition with a chi-square test (with the low-load condition being correct about 65% of the time and the low-load condition being correct only 40% of the time).
The authors suggest that these results offer support for Lavie’s perceptual load theory. They also say that these results have implications for the issue of eyewitness reliability, because oftentimes people see faces when they cannot devote their attentional capacity to those faces.
Important Legal
Disclaimer: The preceding are articles we read together in the Lampinen Lab Spring 2006 false memory reading group. By
clicking on the button next to the article you can see the summary of that
article. The summary was prepared by the student presenting that article and it
is of course the case that the views expressed in the summary do not
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Hugo's, the University of Arkansas, the Razorback Football or Basketball teams
(although we're not sure about cross country), people living down the street
from us, Bob Dylan, Jack Fate, our extended families, or anyone else for that
matter except for the student who wrote the summary (and they don't necessarily
believe what they wrote either).