Inducing the familiarity effect

The task required subjects to judge whether members of six-letter consonant string pairs were physically identical. Some (repeated) strings were presented on each of the 16 training sessions, while other (nonrepeated) strings were presented only during a single session. An advantage in matching time of repeated strings over nonrepeated strings was obtained which increased in a roughly linear fashion during training and which persisted for at least 7 weeks after the last training session. Detailed analyses of the different responses and the results of several transfer tasks suggest that perceptual processing is indeed facilitated by acquired information about which letters usually follow others and about the positions in which these sequences of letters are likely to occur, but provide no evidence that this facilitation derives from the formation of visual features which are larger than single letters.