Abstract
Traditionally, face researchers mainly use static pictures. However, a number of recent studies attempted to reveal the effect of motion information in face recognition. Studies with adult participants indicate a fundamental difference in the effect of motion for familiar and unfamiliar faces (O'Toole, Roark, & Abdi, 2002). Although a facilitative effect of motion is consistently found for the recognition of familiar faces, the effect is less clear for the recognition of unfamiliar faces.
The aim of the present study was to examine the role of motion information on infants' recognition of unfamiliar faces. Several previous studies suggested that motion information promotes infants' perception (Kellman & Spelke, 1983; Otsuka & Yamaguchi, 2003), and therefore we theorized that motion information should facilitate infants' face recognition. In the present study, we compared infants' recognition memory for unfamiliar faces learned in a moving or a static condition.
A total of 24 infants aged 3- to 5- months participated in the present study. Infants were first familiarized with a smiling woman face either in the moving or static condition. The familiarization phase was fixed at a relatively short duration (30 sec). After familiarization, infants were tested using a pair of novel and familiar female faces. Both novel and familiar faces in the test phase had static, neutral expressions. Hair was excluded so that only the internal features were visible. In such a paradigm, we infer that infants have recognized the familiar face, if they show a novelty preference for the novel female face.
We found that the infants in the moving condition showed a significant preference for novel faces, but that the infants in the static condition showed no preference for either of the faces. The present results suggest that learning from moving condition promotes infants' recognition of unfamiliar faces.