https://www.youtube.com/watch?v=TaE7WuNEYocA few months ago my Mum and I were largely ignoring the adverts on our TV when suddenly, one caught our eye. The video (see link above) depicted a somewhat horrible image of an individual’s teeth falling out, before then showing them spit blood after cleaning their teeth. Mum and I both commented on the strangeness of this advert. However, despite our initial reservations it is clear why this advert works: It utilises disgust and fear. According to the Yale Attitude Change Approach (Hovland, Janis & Kelley, 1953) this emotional factor serves as a message variable which helps to change people’s attitudes towards the product. This method is effective because it prompts people to be persuaded via the peripheral route, as described in the elaboration-likelihood model (Petty, & Cacioppo, 1979). When taking this route, individuals are not persuaded by scrutinising the material, but rather by a simple cue such as attractiveness, or in this case emotion. 
Figure 1: Elaboration-Likelihood Model (Petty & Cacioppo, 1979)Indeed, the specific emotions of disgust and fear have been shown as effective in behaviour change through numerous studies covering several domains. For example, Evans et al. (1970) presented junior high school students with persuasive appeals regarding teeth cleaning. They received one of five types of persuasive appeal: High fear, lower fear and positive were all followed by specific recommendations; the fourth involved only specific recommendations and the fifth involved an elaboration of the specific recommendations. It was found that although positive communication resulted in greater information retention, high and low fear groups reported stronger intentions to behave than the positive and elaboration groups. In addition, the high fear appeal group showed greatest reported behaviour change, measured by reported tooth brushing behaviour. However, when assessing actual behaviour change, fear appeals were less effective. Therefore, fear is effective in altering reported behaviour change but not actual behaviour change. 
Figure 2 – Reported behaviour change scores (Evans et al., 1970). HF = High fear; LF = Low fear; POS = Positive; RO = Recommendation only; ER = Elaborated recommendation The effectiveness of fear appeals has been further supported through a meta-analysis of over 100 studies (Witte & Allen, 2000). They found that the stronger the fear appeal, the greater attitude, intention and behaviour change. In addition, the greater the severity of the fear message, the greater the persuasion. Perhaps most notably, Witte and Allen found that individual differences did not influence the extent to which the fear appeal was persuasive, hence suggesting when viewing an advert using fear, individuals will use the peripheral route regardless of personality.Finally, the effect of disgust visuals on attitudes towards animal experimentation was investigated by Nabi (1998). Participants were shown a counterargument and rebuttal of either: low disgust/low affect, low disgust/high affect, high disgust/low affect or high disgust/high affect advert, where low disgust showed a monkey lying on a lab table and high disgust showed a monkey being inflicted with severe head injuries. In addition, low affect refers to showing a talking head, whilst high affect involves showing sick babies who might benefit from animal research. It was found that as the level of disgust increased, level of support for animal experimentation decreased, thus suggesting that disgust is an effective way to change attitudes and hence perhaps behaviour. In conclusion, although being subjected to a Corsodyl advert while watching your favourite television show is far from pleasant, it is an effective way of implementing both attitude and behaviour change. An advert such as this utilises emotions like fear and disgust resulting in an individual being persuaded to go out and buy Corsodyl via the peripheral route.ReferencesEvans, R. I., Rozelle, R. M., Lasater, T. M., Dembroski, T. M., & Allen, B. P. (1970). Fear arousal, persuasion and actual versus implied behavioural change: new perspective utilizing a real-life dental hygiene program. Journal of Personality and Social Psychology, 16, 220-227.Hovland, C. I., Janis, I. L., & Kelley, H. H. (1953). Communication and persuasion: psychological studies of opinion change. New Haven: Yale University Press. Nabi, R. L. (2009). The effect of disgust-eliciting visuals on attitudes toward animal experimentation. Communication Quarterly, 46, 572-484.Petty, R. E., & Cacioppo, J. T. (1979). Issue involvement can increase or decrease persuasion by enhancing message-relevant cognitive responses. Journal of Personality and Social Psychology, 37, 1915-1926. Witte, K., & Allen, M. (2000). A meta-analysis of fear appeals: Implications for effective public health campaigns. Health, Education and Behaviour, 27, 591-615.Charlotte Cartwright