0000000000602794
AUTHOR
Evgenia Boyarskaya
The Mona Lisa effect: Neural correlates of centered and off-centered gaze
The Mona Lisa effect describes the phenomenon when the eyes of a portrait appear to look at the observer regardless of the observer's position. Recently, the metaphor of a cone of gaze has been proposed to describe the range of gaze directions within which a person feels looked at. The width of the gaze cone is about five degrees of visual angle to either side of a given gaze direction. We used functional magnetic resonance imaging to investigate how the brain regions involved in gaze direction discrimination would differ between centered and decentered presentation positions of a portrait exhibiting eye contact. Subjects observed a given portrait's eyes. By presenting portraits with varyin…
Differentiating the differential rotation effect.
As an observer views a picture from different viewing angles, objects in the picture appear to maintain their orientation relative to the observer. For instance, the eyes of a portrait appear to follow the observer as he or she views the image from different angles. We have explored this rotation effect, often called the Mona Lisa effect. We report three experiments that used portrait photographs to test variations of the Mona Lisa effect. The first experiment introduced picture displacements relative to the observer in directions beyond the horizontal plane. The Mona Lisa effect remained robust for vertical and/or diagonal observer displacements. The experiment also included conditions in …
The Mona Lisa effect: Testing the limits of perceptual robustness vis-à-vis slanted images
We report three experiments that test the limits of the Mona Lisa effect. The gaze of a portrait that is looking at us appears to follow us around as we move with respect to the picture. Even if our position is shifted considerably to the side, or if the picture is severely slanted, do we feel the gaze to be directed at us? We determined the threshold where this effect breaks down to be maximally 70? of picture slant relative to the observer. Different factors modulate this remarkable robustness, among them being the display medium and the nature of the picture. The threshold was considerably lower when the picture was mounted on a physical surface as opposed to a computer simulation of sla…