Biomedical subjects

Ruth S Nagayama

Publications and source records attributed to Ruth S Nagayama.

3 recordsLinked to original sources

PubMed2004

Eye direction aftereffect.

Three experiments using computer-generated human figures showed that after a prolonged observation of eyes looking to the left (or right), eyes looking directly toward the viewer appeared directed to the right (or left). Observation of an arrow pointing left or right did not induce this aftereffect on the perceived eye direction. Happy faces produced the aftereffect more effectively than surprised faces, even though the image features of the eyes were identical for both the happy and the surprised faces. These results suggest that the eye direction aftereffect may reflect the adaptation of relatively higher-level mechanisms analyzing the other's eye direction.

Adult↗

PubMed2004

Can mirroring reveal image distortion? Illusory distortion induced by mirroring.

Artists claim that they can find unwanted distortions in their works easily by checking mirror images, suggesting that our sensitivity to distortion is different between normal and mirror images. In this study, participants observed distorted faces in which the left eye was displaced vertically, and judged which of the eyes was higher in both normal and mirror images. The results suggest that mirroring changed the perceptual definition of distortion, rather than sensitivity to it. It is concluded that the distortions that were 'detected' in the mirror images were illusory distortions induced by mirroring. A similar effect was also observed when the images were tilted by 45 degrees clockwise or counterclockwise.

Humans↗

PubMed2002

Perceived eye size is larger in happy faces than in surprised faces.

We demonstrated that perceived eye size is affected by facial expression. Stimuli were composite photographs generated from happy, surprised, and neutral faces. The top halves of the original photographs were separated from the bottom halves by a horizontal line below the eyes, and were pasted onto the superior areas of the happy and the surprised faces. Thus, the composites were happy faces and surprised faces with happy eyes, neutral eyes, and surprised eyes. When the eyes of the happy and the surprised face composites with the same top halves were compared by 142 naïve observers, the happy face composites were judged to have larger eyes than the surprised face composites.

Emotions↗