Biomedical subjects

Claus-Christian Carbon

Publications and source records attributed to Claus-Christian Carbon.

7 recordsLinked to original sources

PubMed2006

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

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.

Adaptation, Psychological↗

PubMed2006

Face-specific configural processing of relational information.

Face processing relies on configural processing, which is thought to be particularly disrupted by inversion. We compared inversion effects in recognition experiments for three types of stimuli, using faces (Experiment 1) and houses (Experiment 2). Stimuli varied by their colour only (colour), by the spatial relations between components (relational), or by the components themselves (eyes, mouths, doors). For faces, relational versions revealed strong inversion effects, component versions moderate, and colour versions no inversion effect. Recognition of houses revealed no inversion effects at all. We suggest that the inversion effects observed for faces in the component condition are due to relational changes, which must accompany any change in components. This proposal may account for the rather inconsistent effects of inversion reported in the literature. Furthermore, we suggest configural processing seems to be somehow face-specific.

Adult↗

PubMed2005

Entitling art: Influence of title information on understanding and appreciation of paintings.

There is evidence that presenting titles together with artworks affects their processing. We investigated whether elaborative and descriptive titles change the appreciation and understanding of paintings. Under long presentation times (90 s) in Experiment 1, testing representative and abstract paintings, elaborative titles increased the understanding of abstract paintings but not their appreciation. In order to test predictions concerning the time course of understanding and aesthetic appreciation [Leder, H., Belke, B., Oeberst, A., & Augustin, D. (2004). A model of aesthetic appreciation and aesthetic judgments. British Journal of Psychology, 95(4), 489-508] in Experiment 2, abstract paintings were presented under two presentation times. For short presentation times (1 s), descriptive titles increased the understanding more than elaborative titles, whereas for medium presentation times (10 s), elaborative titles increased the understanding more than descriptive titles. Thus, with artworks a presentation time of around 10 s might be needed, to assign a meaning beyond the mere description. Only at medium presentation times did the participants with more art knowledge have a better understanding of the paintings than participants with less art knowledge. Thus, it seems that art knowledge becomes significant, if there is sufficient time to assign a meaning and the present studies reveal the importance of considering the time course in aesthetic appreciation.

Adult↗

PubMed2005

The Thatcher illusion seen by the brain: an event-related brain potentials study.

In "Thatcherized" faces, the eyes and mouth regions are turned upside-down. Only when presented upright they are perceived as severely distorted. Common theories explain this effect by the loss of configural information for inverted faces. We investigated neural correlates of Thatcherization using event related potentials (ERPs). Sixteen right-handed participants performed identity classifications on Thatcherized or original familiar faces, presented either for 34 ms or 200 ms at an orientation of either 0 degrees, 90 degrees or 180 degrees. For the occipito-temporal N170, we found (1) strong non-linear effects of orientation and (2) interactions between Thatcherization and orientation: Thatcherization resulted in larger N170 for upright faces, but smaller N170 for inverted faces. The novel finding of N170 effects of Thatcherization in inverted faces suggests differences in the neural encoding of Thatcherized and original inverted faces, even though Thatcherization escapes subjective perception in inverted faces.

Adolescent↗

PubMed2005

When feature information comes first! Early processing of inverted faces.

We investigated the early stages of face recognition and the role of featural and holistic face information. We exploited the fact that, on inversion, the alienating disorientation of the eyes and mouth in thatcherised faces is hardly detectable. This effect allows featural and holistic information to be dissociated and was used to test specific face-processing hypotheses. In inverted thatcherised faces, the cardinal features are already correctly oriented, whereas in undistorted faces, the whole Gestalt is coherent but all information is disoriented. Experiment 1 and experiment 3 revealed that, for inverted faces, featural information processing precedes holistic information. Moreover, the processing of contextual information is necessary to process local featural information within a short presentation time (26 ms). Furthermore, for upright faces, holistic information seems to be available faster than for inverted faces (experiment 2). These differences in processing inverted and upright faces presumably cause the differential importance of featural and holistic information for inverted and upright faces.

Adult↗

PubMed2005

When context hinders! Learn-test compatibility in face recognition.

Some theories of holistic face processing propose that parts in faces (eyes, nose, mouth, etc.) are not explicitly represented. So far, the empirical evidence has shown that whole-to-part superiority is found when wholes are learned. We substantiated this using photographic faces. More importantly, we investigated whether learning parts also reveals holistic effects. This has not been attempted before. Four experiments showed that after learning facial parts, recognition of these parts was disrupted when the part was shown in the full face. This distraction effect was strongest when perceivers were not directed to focus on a particular facial feature. Thus, it is very difficult to ignore irrelevant parts in faces. In fact, this might be the essence of holistic face processing.

Adult↗

PubMed2005

The wall inside the brain: overestimation of distances crossing the former Iron Curtain.

A study of distance estimations between German cities investigated the organization of mental maps and their specific deviations from reality. Potential factors for the deviation of mental maps from reality are physical barriers, emotional involvement, and semantic unity. Distance estimations between cities situated in different former parts of Germany (East or West) were systematically overestimated compared to distances of cities located in the same parts of Germany. This trend was strengthened when participants had a negative attitude toward the reunification of Germany. The impact of these results is far reaching, because overestimated distances between both German parts indicate that there still exists a mental gap between East and West--even in young people--15 years after the German reunification.

Adult↗