Survey of the Infant's "Sound Envelope"
and Organization of Parent-Infant
The early mother-infant relationship has most often been considered to be a dyad, and study of the involved interactions has taken into consideration neither the time and place of the relationship nor its implied social context.
This relationship is paradoxical for it appears to be culture-free. For this reason, all societies have codified and tried to ritualize the caregiving relationship (Héritier, 1977: Rabain, 1979). In fact, this relationship brings us face to face with our own origins. It reveals what is usually hidden: the naked body, the influence of corporality, primary excitability, and erogeneity.
Language, through rules and cultural reverberations, mediates the mother-infant relationship. Similarly, the characteristic sounds, rhythm, and materiality of the caregiver's words respond to the infant's body expressions —indeed, they act as a sort of verbal mirror.
The mother, vocally as well as with support and contact, echoes her infant's excitation, which is expressed through the infant's motility, tonicity, mouth activity, lip vibrations, sighs, breathing, and so forth. The mother responds with body contact as well as through sight, hearing, and speech. She solicits the infant's attention and replies to his or her first vocalizations. These first vocalizations are still largely expressions of body excitement, but they already exhibit an incipient organization of linguistic communication: through the sounds the infant emits and attempts to master and to reproduce, the infant seeks to interact with surrounding people.
With regard to the acquisition of language by infants, interest in maternal vocalizations initially emphasized deformations in conventional syntax; the focus of interest shifted subsequently toward the study of onomatopeias, intensity of voice variation, modulation, and nonsense sounds.
Stern (1977) studied maternal vocalizations within the framework of what he called "infant-elicited social behaviors." He described the syncopated mother-infant training by characteristics of rhythm, timbre, and vocal accentuations, one of whose poles (the effect induced by the infant in the mother) has long been underestimated. He pointed out that the mother's expressions and vocalizations are part of a pattern of signs and postural expressions. The bodily impulses coming from the infant (for example, the agitation of legs and arms,