Can we hear smile?

The amusement expression is both visual and audible in speech. After recording comparable spontaneous, acted, mechanical, reiterated and seduction stimuli, five perceptual experiments were held, mainly based on the hypothesis of prosodically controlled effects of amusement on speech. Results show that audio is partially independant from video, which is as performant as audio-video. Spontaneous speech (unvolontary controlled) can be identified in front of acted speech (volontary controlled). Amusement speech can be distinguished from seduction speech.