Effects of familiarity level and repetition on recognition accuracy

Theories of recognition memory based on signal detection theory posit that a recognition decision is similar to a psychophysical judgment. Like a judgment of stimulus brightness or loudness, a recognition judgment is based on the value of a unidimensional signal computed for the test item. This signal has been called the strength or familiarity value. One prediction of these models is that the ability to discriminate between a studied and nonstudied test item depends on the ability to detect the difference in their familiarities. This ability in turn is influenced by the items' familiarity levels; discrimination should become more difficult as the familiarity of both items increases. This prediction was supported in 3 experiments using a forced-choice procedure. Also, accuracy was higher when the list contained repeated items rather than a comparable number of distinct items.