The Mona Lisa effect: is `our ' Lisa fame or fake?

Abstract. This demonstration uses one of the most famous human faces, the portrait of Mona Lisa, La Gioconda, by Leonardo da Vinci. Usually, we have a very accurate and stable representation of the exact configuration of such a familiar face. Typically, we are able to rapidly recognise even subtle configural changes. However, here we show that an exposure to specific alterations performed on a familiar face substantially reduces this ability even over a time period as long as 80 min. This demonstration illustrates the flexibility of the perceptual system and adaptation to new information. Humans are face experts (Carey 1992). Not only do they process faces extremely fast and accurately (Carbon and Leder 2005b; Yamamoto and Kashikura 1999), but repre-sentations of familiar faces are also stored in human memory for an extended period of time (Bahrick et al 1975). Perceivers are able to discriminate rather subtle aspects of differences between highly similar faces (Leder and Carbon 2004). Relational changes of facial features in unfamiliar faces are detected at the threshold level of visual acuity (Haig 1984; Hosie et al 1988). Beyond the perceptual level, Bruce et al (1991) confirmed this sensitivity for configural information even for memory processes. Participants remembered rather subtle aspects of the configuration of facial features to which they had been exposed earlier. Leder and Carbon (2006) found similar results using faces, but not for houses that were constructed in the same way. Thus, configural information appears to be indeed crucial for human face expertise (Leder and Bruce 2000; Lede