It would be reasonable to expect that our previous experience regarding a stimulus that predicts harm would make the subsequent identification of that stimulus easier when harm happens again. Forty-eight volunteers were submitted to both phases of this sequence of events: learning of the predictive relationship and later priming. A face with neutral expression (CS+) was paired with a moderately aversive electric shock and another (CS−) with a neutral tone. Subsequently, these two faces, as well as other known and new faces, were presented for familiarity judgments. Both the CS+ and the CS− faces were preceded by an aversive stimulus (aversive prime) in one occasion and by a neutral stimulus (neutral prime) in another. The familiarity judgment regarding the CS+ was faster after the aversive prime than after the neutral prime, but there was no difference regarding the CS−. The differential effect of the aversive prime over the CS+ and the CS− showed a significant but small correlation with the differential skin conductance response to CS+ and CS− (signal learning), and with the differential evaluation of those stimuli in terms of like-dislike (evaluative learning). The scope of these results, as well as the usefulness of this methodological model, is discussed.

This experiment compares the yes-no and forced recognition tests as methods of measuring familiarity. Participants faced a phase of 3 study-test recognition trials in which they studied words using all the letters of the alphabet (overlapping condition, O), and an additional phase in which targets and lures did not share any letters (non-overlapping condition, NO). Finally, subjects performed a forced-choice task in which they had to choose one of two new words, each from one of the subsets (Parkin et al., 2001). Results in the NO condition were better than in the O condition in the yes-no recognition test, while the forced-choice rate was significantly higher than .50, showing their sensitivity to familiarity. When the letter set of the words for study in the third list of the NO condition was switched, the difference between NO and O conditions disappeared in yes-no test, while the force-choice rate was not higher than .50. We conclude that both the yes-no test and the forced-choice test are valid and equivalent measures of familiarity under the right conditions.

A method to analyze the role of familiarity in recognizing pictures of everyday scenes is introduced. The idea is to manipulate two within-subjects conditions: an experimental condition where the scenes repeat perceptual information (e.g. buildings and/or vehicles) and a control condition. The results show the two conditions did not differ in terms of hit rates, but in the experimental condition there were significantly fewer false alarms, yielding better results, which supports the findings of past research studies that have used verbal materials. This perceptual facilitation was maintained throughout a week-long retention interval. Finally, a detailed analysis of this facilitation shows it was due to a significant reduction in false alarms on know judgments, emphasizing familiarity's role in explaining this effect.