It’s morphin’ time: Average morphs are more discriminable than single age-progressed images in an identity verification task

Missing persons investigators commission age-progressed images to update appearances of individuals and generate leads from the public. These images have intuitive appeal given they depict a person’s current facial appearance, whereas outdated photographs may generate erroneous leads. One strategy to improve their effectiveness involves ‘morphing’ multiple age-progressions of a single individual made by separate artists into a single image. The present study compared morphs to single age-progressed images in a simultaneous identity verification task. Participants were presented with image pairs featuring age-progressions or morphs alongside real photographs and judged identity on a scale of 1 (not same person) to 6 (same person). Age-progressions were made over three age ranges and comparison photographs depicted targets or foils. Discriminability was greater and response bias more conservative for morphs than for single progressions. ROC analyses revealed morphs at shorter ranges offered greatest performance at every level of subjective confidence.