Matching of Familar and Unfamiliar Faces with Short Exposure Duration

Matching of familiar and unfamiliar faces with short exposure duration was studied. A serial matching task with multiple choice was employed as experimental paradigm. The participants' task was to match a target face (familiar or unfamiliar) with one of four test faces, which were presented after 1500 msec. One of the test faces was a different picture of the person shown as target face, while the other three test faces were pictures of different known/unknown persons. Exposure duration (30 ms and 90 ms), familiarity (familiar vs. unfamiliar faces), and orientation (upright vs. inverted) of target faces were the independent variables. In Experiment 1, whole faces were used as target stimuli. In Experiment 2 only external features were presented as target stimuli. In Experiment 3, only internal features of were shown as target stimuli. The results of our study revealed that matching performance for both familiar and unfamiliar faces was better than chance even for 30ms exposure duration. There was no difference between exposure duration of 30 and 90 ms for familiar faces. However, unfamiliar faces were better matched with 90 msec exposure duration. Familiar faces were matched more accurately than unfamiliar faces in all three experiments. Moreover, familiar faces were matched equally well based on internal and external features, while matching of unfamiliar faces was more accurate based on external than internal features. This result is consistent with earlier findings obtained by De Haan and Hay (1986), Nachson, Moscovitch and Umilta (1995), and Young, Hay, McWeeny, Flude, and Ellis (1985). An inversion effect was found for both familiar and unfamiliar faces in all the three experiments. There was also an interaction between familiarity and orientation suggesting a bigger effect of inversion for familiar than for unfamiliar faces.