The distortion of information during decisions

During a decision might a preexisting preference lead to the distortion of new information in favor of the preferred alternative? An experiment that furnished one alternative with a prior preference found such predecisional distortion. It was also found that in the absence of any initial preference, a developing preference for one alternative led to the distortion of new information so as to favor that leading alternative. The distortion from both sources, preexisting and developing preferences, exceeded the postdecisional distortion from cognitive dissonance reduction.