This article proposes the integration of the subjective, developmental and cognitive aspects of the semiotic processes in a psychological context, and the historical, institutional and ideological fundamentals of sign systems in a sociocultural context. It revisits certain arguments for the rejection of the mind-body dichotomy, investigates the implications of this rejection in terms of the relations thought / language, individual / collective and cognition / emotion, and establishes relations between the process of semiotic mediation and the theory of social representations. It proposes, both theoretically and methodologically, a psychosocial synthesis for human psychological development, forming the basis for psychological intervention in social interaction situations, based on three main points. The focus group is used not simply in order to treat and develop a particular object through conversation, but as a procedure for psychological intervention and a locus of change, presupposing a sequence of group situations, each based on what was produced the previous time. The analysis of the speech acts produced in this sequence of focused conversations reveals participants’ personal paradigms and allows their foundation to be studied. In addition, the Piagetian focus on the grasp of consciousness reveals both the cognitive and metacognitive regulations that occur during the sequence of conversations together with their role in the reelaboration of the premises that form the basis for the personal paradigms and in the grasp of consciousness regarding the possibility of transformation.