Does a three-dimensional Impact Message Inventory-Circumplex (IMI-C) enclose an indirect measure of reactance?

Clinicians can rely on the Impact Message Inventory-Circumplex (IMI-C) to map their emotional reactions to their patients' communication style in octant and main dimension scores on the two-dimensional interpersonal circle, based on affiliation (AFF) and control (CON) as the underlying main dimensions. However, modern emotion theories distinguish three, rather than two, robust dimensions of emotional experience and the perception of interpersonal behaviours: (1) positive versus negative evaluation (related to AFF), (2) strong versus weak (related to CON) and (3) active versus passive (arousal). In a large Dutch patient sample (N = 1,001), we first tested whether the two-dimensional circumplex structure of the IMI-C could be replicated using Browne's circumplex model. Then we explored whether a third dimension could be retrieved from therapists' IMI-C responses using exploratory factor analysis, followed by orthogonal target rotation towards a partially specified target matrix, with the first two factors specified according to the circumplex structure, and the other factor(s) left free. The two-dimensional circumplex of the IMI-C could be validated to a fair extent. Using exploratory factor models, we found supporting evidence for a third factor, which could be interpreted as reflecting reactance ('active' vs. 'passive' opposition). We recommend to extend the current two-dimensional interpretation to a three-dimensional interpretation of IMI-C responses, by adding a reactance dimension.