[Interactions of the infant with its partners: evaluation of preventive and therapeutic approaches].

Interactions between the infant and its partners are defined and described on three levels: behavior, affect, fantasy, with a special focus on the functioning of the infant. The dynamics of the parent/infant relationships are analyzed along transactional theories: the infant and its partners influence each other in a constant process of developing and changing. Together with acknowledging the baby's active role in the relation, we seek better understanding of how the infant shapes up throughout transactions. Different assessment methods of the interactions are analyzed both within a clinical framework and a research framework, and examples of assessment format are given. The transactional perspective in clinical practice with the infant introduces a new model for understanding the pathogenesis of relational disturbances. It appears necessary to conceptualize a specific nosology of interactive pathology, beyond the reference to parental or infant pathology; we thus propose a classification of interactive disturbances by integrating the three levels (behavior, affect, fantasy). The aim of this investigation of interactions, based on an attempt to synthetize anglo-saxon and european research in the field, is to outline a new perspective in clinical concepts and practice which is not solely focused on the description of behaviors in infant interactions with its partners. This viewpoint, resolutely psychopathological in its orientation, implies an empathic approach which leads to important therapeutic changes and legitimizes early preventive interventions.