Modifications of phonetic labial targets in emotive speech: effects of the co-production of speech and emotions

This paper describes how the visual and acoustic characteristics of some Italian phones (/’a/, /b/, /v/) are modified in emotive speech by the expression of joy, surprise, sadness, disgust, anger, and fear. In this research we specifically analyze the interaction between labial configurations, peculiar to each emotion, and the articulatory lip movements of the Italian vowel /’a/ and consonants /b/ and /v/, defined by phonetic-phonological rules. This interaction was quantified examining the variations of the following parameters: lip opening, upper and lower lip vertical displacements, lip rounding, anterior/posterior movements (protrusion) of upper lip and lower lip, left and right lip corner horizontal displacements, left and right corner vertical displacements, and asymmetry parameters calculated as the difference between right and left corner position along the horizontal and the vertical axes. Moreover, we present the correlations between articulatory data and the spectral features of the co-produced acoustic signal.