Perceptual complexity of faces and voices modulates cross-modal behavioral facilitation effects

Abstract

Joassin et al. (Neuroscience Letters, 2004,369,132-137) observed that the recognition of face-voice associations led to an interference effect, i.e. to decreased performances relative to the recognition of faces presented in isolation. In the present experiment, we tested the hypothesis that this interference effect could be due to the fact that voices were more difficult to recognize than faces. For this purpose, we modified some faces by morphing to make them as difficult to recognize as the voices. Twenty one healthy volunteers performed a recogniton task of previously learned face-voice associations in 5 conditions: voices (A), natural faces (V), morphed faces (V30), voice-natural face associations (AV) and voice-morphed faces associations (AV30). As expected, AV led to interference, as it was less well and slower performed than V. However, when faces were as difficult to recognize as voices, their simultaneous presentation produced a clear facilitation, AV30 being significantly better and faster performed than A and V30. These results demonstrate that matching or not the perceptual complexity of the unimodal stimuli modulates the potential cross-modal gains of the bimodal situations.

Keywords

• Cross-modal
• Facilitation
• Faces
• Voices