The focus prosody: more than a simple binary function

The prosodic focus conveys the information of the yes/no deixis function on a given linguistic domain, generally the word, quite in all languages, and presumably in an universal morphology. Our proposal is that the prosody of focus conveys together some complementary information: the domain of the deixis (phone, syllable, word, larger) and a gradient functional value of insistance which could be controlled with the illocutory force. In this aim, a corpus of isolated French sentences was recorded, with two consigns: to point on the word vs. to point on the syllable, in varying the place of the syllable in the word. Different kinds of perception tests were held A first experiment confirms the validity of the recorded corpus, shows that a focus is perceived on a word or on a syllable whatever the place of the syllable. An acoustic analysis shows that the word condition is implemented by a prominence on the first syllable (as usually attested in French) and that the acoustic profile of the syllable vs. word focus is similar in tonal description but opposable in a dynamic description. A categorical perception experiment, held on stimuli progressively morphed from the no focus condition to the focus condition as produced by the speaker, makes clearly appear the binary decision of the focus function processed by the listeners. The limit values of F0, intensity and duration, give the basic level of the beginning of the gradient function of focus. This focus description is integrated in a general model of prosody, based on superposition of functional gradient contours, including the linguistic and paralinguistic functions of prosody [1].