Long-term effect of decision-making processes

According to Festinger (1954, p.158), little was known about “the conditions under which dissonance reduction will be stable and lasting”. Our experimental results gave at least a partial answer, and lines up with the following statement by Lewin (1951, p.233):

“a process like decision [making] which takes only a few minutes is able to affect conduct for many months to come. The decision links motivation to action, and at the same time, seems to have a “freezing” effect which is partly due to the individual’s tendency to ‘stick to his decision’”.

The results of the Experiments 7-9 indeed demonstrated that although preferences appear to be flexible because they are modulated by choices, this modulation also appears to be stable over time. Our results demonstrated this stability at 1 week, but a recent result suggests that it may even reach up to three years (Sharot et al., in press).

Moreover, facing the same choice one week later, our participants displayed a high likelihood of making a second choice similar to the first one, even though one week had passed. This result was interesting per se because the coherence of choices has been challenged by numerous experimental studies. The most well-known study has shown the

now famous framing effects: framing a similar choice problem in different ways can strongly affect the choice (Tversky & Kahneman, 1981). In addition to framing effects, other preference reversals² (Lichtenstein & Slovic, 1971) that are linked to changing description of the options or procedure (choice) have been reported (see Lichtenstein &

Slovic, 2006). Moreover, changing the available options, like adding a third option to a binary choice, can also lead to preference reversals (Busemeyer, Johnson, & Jessup, 2006).

However, even if a number of factors can affect the choice, a bias towards an option designated previously as preferred could be displayed. In comparing neutral framing - where participants had to make a choice between options with no specific status - with status quo framing - where one of the options corresponded to an already chosen option and the other options to possible alternatives - participants display a status quo bias (Samuelson & Zeckhauser, 1988).

Although interesting, we do not want to give too much informative weight to this high choice coherence, as it might be based on the differential hedonic evaluation between chosen and rejected odors before the second choice. Hence, after the first choice, postchoice preference modulation had already occured, i.e. chosen odors were on average rated as much more pleasant than the rejected ones. This may have made the second choice an easier one, based on this a-priori pleasantness difference between the paired odors.

Taken together, this evidence still suggests that arbitrary-seeming momentary decisions can have a surprisingly long-term effect on preferences, and our results tend to suggest that this may be true even if the triggering decisions are forgotten.

We believe that the asymmetry between the fleetingness of the cause and the long-lastingness of its effect is particularly informative regarding olfactory preference modulation and stability across time, as well as regarding the potential importance of implicit processing.

First, regarding olfactory preference modulation and stability across time, our results suggest that the impact of decision-making processes might be particularly pervasive. They could indeed modulate olfactory preferences even if the decisions do not have direct consequences for the participant, and once they have done so, this influence

2 In the context of economics, as we described in section 2.1.2, preferences are very often defined via choices, and not via evaluations of stimuli in the sense of liking/disliking, as the definition adopted here.

will last over time. How could we explain this result ? As we mentioned in section 2.4.5, the mere act of thinking about on option is sufficient to create a sense of pre-factual ownership of the option and an increased sense of loss after choosing another option (Carmon, Wertenbroch, & Zeelenberg, 2003). The subjective feeling of ownership (Reb, &

Connolly, 2007), or in our case, of commitment to an option, could consequently lead to preference modulation, even in the long run, despite the fact that this commitment had no direct consequences. Note that this mechanism could occur in addition to choice-supportive source monitoring, i.e. the fact that people tend to attribute more positive features to an option they have chosen, which is already present 45 minutes after choice (Mather, Shafir, & Johnson, 2000).

Second, our results add to the body of empirical evidence which shows the importance of implicit processing in olfactory preferences by demonstrating their impact in the long run. Explicit cognitive factors such as the use of specific verbal labels (de Araujo, Rolls, Velazco, Margot, & Cayeux, 2005; Herz, 2003; Herz & von Clef, 2001), information about brands (McClure et al., 2004), price (Plassman, O’Doherty, Shiv, &

Rangel, 2008), have been shown to strongly influence chemosensory pleasantness evaluations and preferences. The question of implicit influences appears however to have received less attention, in particular with regard to their long-term stability. Let us emphasize a major piece of evidence in this respect: the mere exposure effect, i.e. an increase in preference for a stimulus due to its repetition. An important factor in preference modulation, mere exposure effects have been shown to occur even when stimuli are presented subliminally (Bornstein & D’Agostino, 1992). These effects are impaired with stimulus recognition (Bornstein, 1989). As olfactory stimuli are particularly well suited to study implicit memory (Issanchou et al., 2002), the modulation of olfactory preferences by implicit processes (both immediately after choice but also after some time has passed), appears as a particularly relevant avenue of research.

Finally, the evidence that preferences demonstrated both some flexible aspects, as they can be modulated by decision-making processes, and some inflexible aspects, as this modulation is stable, has consequences on their theoretical conceptualization. As stated by Scherer, preferences may be underpinned by current goals, which would provide some flexibility; in our case, pursuing goals linked to the decision just made. But preferences could also be underpinned by a process that one might want to label “intrinsic

pleasantness”, i.e. a strongly determined association between a given stimulus and a particular hedonic tone, which would be quite long-lasting. The flexibility and stability of preferences might be linked to the interaction between several components. Specifically, these can include the intrinsic pleasantness of a stimulus, as well as the person’s current goals and their respective weights. A goal is an internal representation of a desired state (Austin and Vancouver, 1996), whereas wanting refers to the incentive salience of a stimulus (e.g. Berridge, Robinson, & Aldrige, 2009). Therefore the extent to which an option is conducive to a person’s weighted goals in a given situation may affect how much they want that particular option. The idea that valuation should not be viewed as pertaining to liking or wanting in isolation has been discussed in the literature. For instance, Higgins (2006) argued that value is a combination between a hedonic experience and an experience of motivational force, i.e. “experiencing the force of attraction towards something or repulsion away from something” (p. 439).

In the experimental design from the free-choice paradigm, it appears plausible that the first pleasantness rating primarily reflects a hedonic value, i.e. liking, as no choice is involved. The choice that follows in the next phase might then be considered primarily as an expression of wanting (in other terms, which one of the two do you want more?).

Note that wanting, of course, will probably be informed by predictions of liking, so that it would not be accurate to say that liking is not at all at play. Furthermore, after choice has taken place, the following pleasantness ratings that record the hedonic value of the stimuli may be affected by the choices, so that previous wanting may in fact affects subsequent liking.

In addition, the appraisal of pleasantness may be processed by more than one system of processing (Leventhal & Scherer, 1987). According to this article, at the sensory motor level, pleasantness reflects innate preferences and aversions. Furthermore, at the schematic level, pleasantness is thought to reflect learned preferences and aversions.

Finally, at the conceptual level, pleasantness may reflect recalled, anticipated, or derived positive-negative evaluations (see Table 2 in Leventhal & Scherer, 1987). Thus potentially, liking and wanting may operate differently at different levels of processing.

The theoretical position assuming that liking and wanting interact would fit with the recent proposition of Warren and al. (2011) regarding preference construction. These authors suggest that “the extent to which preferences are calculated seems to be be influenced by the goals, cognitive constraints, and the experience of the decision maker”

(p. 202). They also suggest that this construction is a continuum. Note that the importance of goals has been similarly emphasized by Heckhausen and Gollwitzer (1987), who demonstrated that thoughts about goal options were particularly salient before a decision had been made. After a decision has been made, the goal related to the chosen alternative is assumed to be implemented (Beckmann & Gollwitzer, 1987).

4.2.4. Summary of this part

Our experimental part lead to the conclusion that (i) olfactory preferences can be modulated by decision-making processes; (ii) this shaping does not require explicit processes, and (iii) the change can be long-lasting. These three pieces of evidence have important theoretical implications, not only for the main theory in the field of preference modulation induced by choice – cognitive dissonance theory (Festinger, 1957), but also for hypotheses derived from it (e.g., the action-based model of cognitive dissonance) and less directly related to it (e.g., endowment effects). We hope this work may contribute to the further integration of different theories of preferences by helping to tackle the question of how preferences can be modulated by decision-making processes, while not necessarily requiring explicit processes. In this respect, appraisal theories of emotion (Sander, Grandjean, & Scherer, 2005) might be inspirational regarding processes underlying preferences, which are also an affective phenomenon, but are not emotions.

Since we believe it is important to put this work into perspective, we will now discuss its limitations and possible future developments.