A new study has shown that facial expressions are far more clear in motion pictures than static photographs.
According to scientists from the Max Planck Institute for Biological Cybernetics in Tübingen, Germany, the video sequence needs to be at least as long as one tenth of a second to gain this dynamic advantage. If the video sequence is shorter, our brain is less capable of interpreting the facial motion. Some expressions rely on changes in head orientation, for example, a nod or a shake of the head, others on the complex deformation of facial parts, such as wrinkling our nose to signalize disgust or a frown.
"Facial expressions, like gestures and body motion, are a dynamic phenomenon and need to be investigated with the help of video sequences in order to get a better understanding of the dynamic information that is being processed," says Dr. Christian Wallraven, co-author of the study.
"Our results also have implications for the area of computer animation, since its goal is to create artificial avatars and facial animations that are able to communicate realistically and believably," says the physicist and perception scientist.