Do the major tendencies of phonological systems of languages depend on constraints of production and perception ? This problem has been studied in the framework of "substance oriented" linguistics, which was introduced simultaneously by Lindblom and Stevens in 1972. Various universal tendencies of phonological systems that might be explained by the characteristics of the sound structures and could be looked upon from an ontogenetical perspective, will be presented and discussed here. The characteristics and the predictability of vocalic and syllabic systems seem to be eminently suited for the study of this question on the basis of research carried out at the ICP.

This article aims to investigate experimentally the links between prosody and the various domains of linguistics (syntax, semantics, pragmatics). Since the function of prosody is to convey the interpretation of the meaning the speaker wants to give to his utterance, the method that is proposed is to define linguistic models that can be quantified in such a way as to both yield an interpretive strategy of the linguistic contents and to predict a melodic structuring of the lexical framework. Experimental evidence shows links between on the one hand constraints related to the text and the context, and on the other the distribution of models and melodical indices, and allows us to define prosody and more in particular melody, as a subjective locus, where whatever belongs to the linguistic realm enters the realm of pragmatics.

Deixis, or pointing, is the ability to draw the viewer/listener’s attention to an object, a person, a direction or an event. Pointing is involved at different stages of human communication development, in multiple modalities: first with the eyes, then with the finger, then with intonation and finally with syntax. It is ubiquitous and probably universal in human interactions. The role of index-finger pointing in language acquisition suggests that it may be a precursor of vocal pointing or that vocal pointing may be grounded in the same cerebral network as gestural pointing.

If dysphonia is clearly identified as a phonation disorder, dysarthria is often wrongly restricted to an arthric impairment. Actually, dysarthria is a motor speech disorder, whose origin is a lesion of the central or peripheral nervous system; it involves various possible deteriorations during the motor execution of speech, which influence respiratory, phonatory, resonatory, articulatory, and prosodic aspects of speech production. The distinction between dysphonia and dysarthria based on which anatomical level is lesioned does not accurately explain the duality between these terms; on the other hand, a distinction rather based on the neurological origin of the disorder would seem more adapted to describe as precisely as possible the multiple dysfunctions of voice and speech. In fact, the study of dysarthric and dysphonic speech for the better understanding of normal speech represents an original approach, which considers speech disorder as a model of its own for speech investigation.