Post-decision Processes : Consolidation and value conflicts in decision making

The studies in the present thesis focus on post-decision processes using the theoretical framework of Differentiation and Consolidation Theory. This thesis consists of three studies. In all these studies, pre-decision evaluations are compared with post-decision evaluations in order to explore differences in evaluations of decision alternatives before and after a decision. The main aim of the studies was to describe and gain a clearer and better understanding of how people re-evaluate information, following a decision for which they have experienced the decision and outcome. The studies examine how the attractiveness evaluations of important attributes are restructured from the pre-decision to the post-decision phase; particularly restructuring processes of value conflicts. Value conflict attributes are those in which information speaks against the chosen alternative in a decision. The first study investigates an important real-life decision and illustrates different post-decision (consolidation) processes following the decision. The second study tests whether decisions with value conflicts follow the same consolidation (post-decision restructuring) processes when the conflict is controlled experimentally, as in earlier studies of less controlled real-life decisions. The third study investigates consolidation and value conflicts in decisions in which the consequences are controlled and of different magnitudes. The studies in the present thesis have shown how attractiveness restructuring of attributes in conflict occurs in the post-decision phase. Results from the three studies indicated that attractiveness restructuring of attributes in conflict was stronger for important real-life decisions (Study 1) and in situations in which real consequences followed a decision (Study 3) than in more controlled, hypothetical decision situations (Study 2). Finally, some proposals for future research are suggested, including studies of the effects of outcomes and consequences on consolidation of prior decisions and how a decision maker’s involvement affects his or her pre- and post-decision processes.

Subliminal or not? : An appraisal of semantic processing in the near absence of visual awareness

Stimuli that cannot be perceived (i.e., that are subliminal) can still elicit neural responses in an observer, but can such stimuli influence behavior and higher-order cognition? Empirical evidence for such effects has periodically been accepted and rejected over the last six decades. Today, many psychologists seem to consider such effects well-established and recent studies have extended the power of subliminal processing to new limits. In this thesis, I examine whether this shift in zeitgeist is matched by a shift in evidential strength for the phenomenon. This thesis consists of three empirical studies involving more than 250 participants, a simulation study, and a quantitative review. The conclusion based on these efforts is that several methodological, statistical, and theoretical issues remain in studies of subliminal processing. These issues mean that claimed subliminal effects might be caused by occasional or weak percepts (given the experimenters’ own definitions of perception) and that it is still unclear what evidence there is for the cognitive processing of subliminal stimuli. New data are presented suggesting that even in conditions traditionally claimed as “subliminal”, occasional or weak percepts may in fact influence cognitive processing more strongly than do the physical stimuli, possibly leading to reversed priming effects. I also summarize and provide methodological, statistical, and theoretical recommendations that could benefit future research aspiring to provide solid evidence for subliminal cognitive processing.