Creating coherence in real-life decision processes: Reasons, differentiation and consolidation.

Differentiation and Consolidation Theory describes human decision making as a process in which attractiveness values are restructured in order to reach a decision and support the decision made. Here, the theory was developed to include reasons pro and con alternatives and tested on students making decisions between two university psychotherapy training programs (cognitive-behavioral and psychodynamic therapy). Before and also after the decision, the attractiveness of the chosen alternative was upgraded and the non-chosen alternative downgraded. Different measures of evaluations of an alternative, such as "best" or "worse" converged over time until shortly after the decision. The number of reasons pro and con alternatives give a more complete picture than attractiveness and increased from the first to the last session. The reasons supporting the chosen alternative increased in strength, but reasons against the non-chosen alternative decreased. In informal comments participants reported that the study also served as a decision aid.