We are now ready to consider the theories and models that have been forwarded in light of the empirical evidence that we and others have amassed. We begin by briefly recapitulating the main theses of the fifteen or so models and theories that we have examined, then consider the most important conclusions from previous empirical research and from our own investigations reported in Chapters 9 and 10. Against this backdrop, we sketch a new model of interaction adaptation.

THE EXTANT THEORIES

The biologically based models (e.g., Interactional Synchrony, Motor Mimicry, and Mirroring) largely predict that interacting individuals will exhibit similar patterns to one another – similar in terms of their visual and vocal composition or their temporal properties or both. These adaptation patterns are presumed to have an innate basis, owing perhaps to their survival value and their satisfaction of such basic needs as bonding, safety, and social organization. Consequently, they are presumed to be universal and largely involuntary, although it is recognized that numerous environmental and social factors may facilitate or impede their enactment.

The class of arousal–based and affect–based models includes some of the most well–recognized and tested of the interaction adaptation theories. These theories share in common a belief that internal emotional and arousal states are driving forces in people's decisions to approach or avoid others. Affiliative Conflict Theory (ACT), also known as Equilibrium Theory, posits that interactions are characterized by some comfort level that balances needs for approach and affiliation with needs for avoidance and privacy.