People tend to pick out a face in a crowd more quickly when teeth are visible — whether smiling or snarling — than a face with a particular expression.
The results counter the long held “face-in-the-crowd” theory that proposes angry faces as being the most readily detected in a large group.
“The research concerned with the face-in-the-crowd effect essentially deals with the question of how we detect social signals of friendly or unfriendly intent in the human face,” said author Gernot Horstmann, PhD, of the Center for Interdisciplinary Research and Department of Psychology at Bielefeld University, Germany.
“Our results indicate that, contrary to previous assertions, detection of smiles or frowns is relatively slow in crowds of neutral faces, whereas toothy grins and snarls are quite easily detected.”
The researchers conducted two studies in which they asked participants to detect a happy face or an angry face in a crowd full of neutral faces, and measured the search speed.
While the search was fairly slow when emotion was displayed in a closed mouth face, the search speed doubled when emotion was signaled with an open mouth and visible teeth.
This occurred for both happy and angry faces, and happy faces were usually picked out more quickly than angry faces.
The team conducted this research in an attempt to clear up previous inconsistencies in similar studies.
According to the researchers, the conflicting results with respect to which of the two expressions are noticed more quickly — the happy face or the angry face — suggested that the emotion was probably not the only important determining factor in the face-in-the-crowd effect.
The researchers believe this new study may explain previous inconsistencies. “This will probably inspire researchers to clarify whether emotion and, in particular, threat plays an additional, unique role in face detection,” said Horstmann.
Source: Journal of Vision