The concept of dyadic interdependence describes the mutual influence of relationship partners on their behavior and experience. The research project focuses on interdependence between motivational dispositions and processes in intimate couple relationships. While in personality psychology interdependence is usually investigated descriptively via the identification of partner effects or interaction effects between the partner' dispositions, the project takes a functional-explanatory perspective.
Specifically, a theoretical model (MIC model) is tested that postulates motivational and cognitive mechanisms to explain the interdependence of motivational dispositions in couple relationships. The motives of the partner are conceptualized as environmental conditions that affect the motivation process of the actor in (1) the phase of motive arousal and (2) the subsequent phase of implementing motivated behavior. However, since the partner's motives (as well as current motivations) are hypothetical constructs and thus not directly observable, their effects on the actor's motivation process must be mediated via observable partner behavior and the actor's subjective perception of it. Core assumptions of the MIC model were already corroborated by correlational analyses of dyadic experience sampling data.
The research project aims at (1) causal tests of the postulated interdependent mechanisms by using experimental methods and (2) a more objective and differentiated assessment of couples' interaction behavior than realized in previous studies by using observational methods. To these ends, a comprehensive behavioral observation study with heterosexual couples is implemented, in the course of which the motivation of the partners will be experimentally manipulated. The observation study in the laboratory is framed by two online surveys for the assessment of motives and relationship quality one year apart. In addition to testing the MIC model, this design allows for the investigation of dynamic transactions between motives and relationship quality as well as the analysis of mediating interaction patterns.
Overall, by connecting intra-individual and intra-dyadic mechanisms to the inter-individual level of personality, the research project makes an important contribution to the integration of perspectives on dyadic interdependence from motivation, relationship and personality psychology. In the long term, the project findings should also inform applied psychology, especially in the development of empirically grounded counseling and intervention programs that support the optimal implementation of individual motives in couple relationships.