This is a draft of my proposal, and I might present it in one of the next Tuesday sessions. Welcome to comment on it. If you don't like it, throw it in the dustbin :)
Disgust, as an universal emotion, is believed to originate in the mammalian bitter taste rejection system. People who have experienced relevant unpleasant tasting bitter, sour or salty express a strong emotion of disgust (Chapman et al., 2009). Rozin, Haidt and Fincher (2009) suggested this evaluation of disgust reflected our most basic biological reaction to avoid the physical disgusting source, and the “disgust output” came out even without cognitive evaluation. Rozin and Fallon (1987) mentioned the disgust is original food-related emotion, which protects us to get disease from the disgusting source. Rozin, Haidt and Fincher(2009) pointed out, during human’s evolution, our disgust output system was harnessed to a disgust evaluation system which responded not to our sensory inputs (eg. Bitter flavor) but to more cognitive appraisals (eg. spider). That is, the disgust evaluation system originally worked for evaluating potential risky food on the basis of the food’s nature or perceived origin. Later on, the category which elicited the feeling of disgust was enlarged though some combination of biological and cultural evolution. Hence, the disgust evaluation system started to deal with other types of disgust, like the reminder of our animal nature and moral offense (Rozin, Haidt & Fincher, 2009). It seems that those further mentioned moral violation (offense) shares a closing relationship with other basic pathogen disgusting source (eg. disgusting food), since all these elicitors actually activate similar disgust output. Therefore, Chapman et al. (2009) argued that the feeling of disgust is evolved from oral to moral. Several evidence has been found to support this argument. For instance, Zhong and Liljenquist (2006) reported that physical cleansing alleviates the upsetting consequences of unethical behavior and reduces threats to one's moral self-image, which suggested a psychological association between bodily purity and moral purity. In other words, their research inferred that the physical disgust is correlated with a abstract level of moral disgust. Another research from Schnall et al. (2008) found that priming people with the physical disgust source would make subsequent moral judgment more severe. Furthermore, evidence from neuroscience suggested that both of the temporal and frontal cortices in our brain were activated when people either feel physical disgust or moral disgust (Moll et al., 2005). More interestingly, Chapman et al. (2009) found that participants showed a similar facial motor activity when they experienced disgusting taste, saw disgusting pictures or was involved in unfair decision making. More and more evidence like those aforementioned suggested that our moral judgment and gustatory judgment might share a same disgust evaluation system. Recently, Eskine, Kacinik and Prinz (2011) reported that people’s taste perception could significantly influence their moral judgment. That is, the more immoral judgment outcome could be introduced by guiding people experience a physically disgusting taste. These authors ascribed the reasons of their finding to the association link between physical disgust and moral disgust, such that disgusting taste perception would elicit greater disgusting feeling on moral evaluation. This finding itself revealed a consistent prediction with the “disgust is from oral to moral” hypothesis. In addition, it also suggested that our embodiment processing could influence our moral judgment that is seen as a high level cognitive processing. However, our current question is: Does the high level of cognitive processing influence our embodiment processing?
We argue that if the reported effect is indeed due to the morally introduced feeling of disgust, we might suspect that the feeling of moral disgust could subsequently trigger our sensitivity change for our taste perception, since disgust as a general emotion could reflect our reaction on both taste perception and perception on moral judgment. In addition, if the moral feeling of disgust belonging to the same category as the disgust feeling from physical disgust, we might also expect that the morally introduced feeling of disgust would cause a more physical disgust feeling from the taste in food or drinks. As suggested by Schwarz and Clore (1983), affect as a type of information, were also frequently used in our decision making. Therefore, we predict people who experienced a moral disgust might be easily to transfer their feeling of disgust to other domains, such as their taste perception. As the flavor of bitter, sour and salty are much correlated with the basic gustatory of disgust (Chapman et al., 2009), we suspect that people might become more sensitive towards these taste flavors. That is, people might feel more sour, bitter, or salty if they feel morally disgusted. On the other hand, other taste like spicy and sweet are irrelevant with the feeling of disgust. Hence, we didn’t expect the morally introduced feeling of disgust would influence people’s perception on these taste. As follows, three studies are proposed to test our hypothesis.
Study 1 aims to figure out if our taste perception could be influenced by previous introduced moral judgment, especially by the introduced moral disgust feeling. The experiment is a 5(Beverage types: sweet, salty, sour, bitter, spicy)* 2 (Moral judgment type: moral disgust, moral control) between subjects design. Both beverage type and moral judgment type are between subject factors. Participants are asked to evaluate one type of liquid juice after they evaluate either moral disgusting stories or control stories, and the liquid juice is randomly selected from one of the five options which have different taste. We predict that people might report more flavor of salty, sour or bitter in the moral disgust condition than those in the control condition. But there might be no effect for the sweet or spicy juice.
Study 2 tries to replicate study 1, and further intend to show that our taste could be misled by the introduced feeling of disgust even without physical contracting with the stimulis owning flavors (eg. Water). Furthermore, if our prediction is correct, we also suspect that the moral admired story might not influence our taste perception on sour, bitter or salty. However, on the other hand, the flavor of sweet is correlated with positive affect (Baron , 1997). Hence , it is possible that the moral admired story, for example, the moral story which might introduce the feeling of love, would make people feel more sweet taste, but this positive feeling can’t affect other tastes, like bitter, sour, etc. So we plan to set up three conditions in this study. They are moral disgust condition, moral neutral condition and moral admired condition. In the experiment, participants are asked to evaluate an unknown beverage in a small cup. Actually, the beverage is water, but we told participants it is a new type of beverage. After they are randomly asked to evaluate one of the three types moral stories, participants are further asked to indicate their taste perceptions on different taste dimensions (ie. sweet, sour, bitter, spicy, salty).
The last study is designed for testing a possible moderator on our proposed effect. That is, we suspect that disgust sensitivity might moderate our prediction. So people who are more sensitive towards the disgusting stimulis might show a stronger feeling transferring effect. In other words, those people might feel more stronger on their taste feeling of sour, bitter or salty after evaluating moral disgusting stories.
Ask me relevant reference if you need