Unfamiliar face matching, within-person variability, and multiple-image arrays

Human unfamiliar face matching is error-prone, but some research suggests matching to multiple-image arrays instead of single images may yield improvements. Here, high or low variability arrays containing one, two, and three images, and a target image from the high and low variability image sets were displayed. Arrays were presented simultaneously or sequentially, and the target image was presented simultaneously with arrays or sequentially after arrays, in three experiments. Benefits from exposure to multiple images of the same person required simultaneous viewing of images and improvements were observed in match trials only. Only sequential viewing of a multiple-image array followed by a high variability target image enhanced overall accuracy across trial types, particularly for high variability arrays. Accuracy was highest when the target image and array items were visually similar. Results show the importance of image similarity, and suggest variability is most helpful when array and target are presented sequentially.