Another dual process theory was one which was devised by Nemeth (1986), Whereas Moscovici elaborated little on this comparison process, Nemeth argued that the stressfulness of such situations by the majority lead to a relatively superficial processing by which group member's attention and thought converge on the majority's stated position but do not extend to a full consideration of the issue. Minority sources are postulated to stimulate a greater amount of thinking, and this thinking tends to be more divergent, where the term divergent refers to thinking that branches out from the information that is given and focuses on new information and possible alternative positions. However, Nemeth's dual process theory leads to a more heuristic processing.
Moscovici's dual process theory resembles some peripheral-centred distinctions which are included in the Elaboration Likelihood Model of persuasion (Capioppo & Petty, 1987). The term 'elaboration' in the title refers to the extent to which a recipient of a persuasive message message studies, analyses and evaluates issue-relevant information already in the memory. Persuasion can have its influence through one or two metaphorical channels: The Central route or the Peripheral route. Sometimes, the elaboration is high, the recipient engages in a great deal of scrutiny of the central issues and tends to ignore 'peripheral' matters such as source credibility. Othertimes, the elaboration is low, and it is highly unlikely for the recipient to process the message itself and relies on peripheral factors to change her/his attitude. In some persuasion situations, the likelihood of message elaboration and issue relevant thinking is high. Cacioppo and Petty (1987) said that in these situations, people do two things. Firstly, because perhaps the message has direct personal relevance, personal responsibility is high or they are the kinds of people that enjoy thinking, they are highly motivated to devote the cognitive work necessary to evaluate the message. Secondly, because perhaps the message is repeated several times, distractions are few, or they have considerable issue-relevant knowledge, they are extremely able to evaluate message, However, in other situations motivation and/or ability to process issue-relevant information is quite low. In these situations simple cues may induce agreement without scrutinising the argument.
A persuasive communication might be the result of either central or peripheral processing or a combination of the two. There are a large number of possible combinations and factors. Persuasive communications can contain strong or weak arguments, these messages can be associated with positive or negative cues such as source credibility and different recipients might engage in low, medium, or high levels of elaboration, as represented by respected levels of motivation and ability. The peripheral route would be utilised to appraise if elaboration were low, and the unscrutinized argument factors would be overridden by the cue effects. If elaboration was moderate, the impact of the peripheral cues would be diminished by the argument factors coming into play. If the elaboration were high, the power of the arguments would override the impact of the peripheral cues altogether as the amount of agreement with the messages would be high.
Findings of a number of experiments have supported predictions of the Elaboration Likelihood Model. Wu and Shaffer (1987) produced one such study and based their research on earlier findings that direct versus indirect experience with an object produces variations in attitudes toward that object. There were two types of peanut butter (the object) involved: Product X and Product Y. Wu and Shaffer (1987) reasoned that people who had direct experience with the product would be more likely to follow the central route in the persuasion process, since their attitudes would have "evolved from a thoughtful elaboration of self-generated information that is likely to be clear, involving and accessible." With the people with attitudes based on indirect experience, their statements should be "less likely to have been extensively elaborated and thus are less clear, involving or accessible."
Subjects were confronted with a persuasive communication that argued that Product Y was the better type. Half the subjects received the message from a highly credible source, whilst the other half got the message from a less credible source. Results showed that there was more agreement with the persuasive communication about product Y in the indirect-experience group and an especially high level of agreement in those particular subjects who had heard from a highly credible source. To summarise, a formulation like the Elaboration Likelihood Model permits us to understand the differential impact of a persuasive communication in terms of audience variables.
Although Petty and Cacioppo's framework has contributed to a resurgence of interest in persuasion process among social psychologists, the elaboration likelihood model constitutes primarily a descriptive, rather than explanatory theory of persuasion. As Petty and Cacioppo have themselves brought up, their model does not indicate why certain arguments are strong or weak, why certain variables serve as peripheral cues, or why certain variables affect information processing. The fit between observed persuasion data and the model's ideal data patterns has been used to infer that the sheer number of arguments provided can enhance objective message processing when the elaboration likelihood is high, that prior knowledge enhances biased message processing, and that source variables enhance (or reduce) objective message processing when the elaboration is moderate. These inferences are descriptive ones, because the model does not specify why exposure to many arguments ought to motivate or enable objective processing, why prior knowledge ought to motivate or enable biased processing, or why source variables ought to motivate objective processing when the elaboration likelihood is moderate.
Another ambiguity of the Elaboration Likelihood Model is that it provides no conceptual rationale for its premise that peripheral cues should be relatively unimportant determinants of persuasion when the elaboration likelihood is high. It is difficult to see if people knowingly ignore peripheral cues such as source attractiveness, pleasant music, and consensus information in such circumstances. Or if they do not ignore them, it is difficult to see that they do somehow resist being influenced by peripheral mechanisms such as identification, classical conditioning and heuristic processing in there situations.
The model's peripheral route label lacks theoretical depth because the theories that are assumed to compromise this route differ widely in their assumptions regarding recipient motives in persuasion situations, and in the process they highlight as mediators of persuasion. Because the Elaboration Likelihood Model specifies when peripheral route persuasion should and has occurred, but not which peripheral mechanism has operated, it leaves numerous mediational issues unaddressed. The model's basic assertions are that central route theories predict behaviour best when the elaboration likelihood is low, and that central route theories are more predictive of attitudinal persistence, resistance, and attitude-behaviour consistency. These ideas, although are valuable and deserve continued exploration by researchers, it is not clear what other theoretical insights follow from the model's bifurcation of attitude theories.
Petty & Cacioppo's labelling of the argument 'quality' and the descriptions of strong and weak messages have been features in their research imply the latent variable is the inherent strength, plausibility, or believability of a message's arguments. Areni & Lutz showed that a set of "strong" arguments and a set of "weak arguments" did not differ in their perceived strength (i.e. likelihood).
References
Areni & Lutz (1988) "The Role of Argument Quality in the Elaboration Likelihood Model" Consumer Research, 15, 197-203.
Cacioppo, J. & Petty, R. (1987) "Stalking Rudimentary Processes of Social Influence: A pyschophysiological approach. In M.Zanna et al, Social Influence. Hillsdale,NJ: Lawrence Erlbaum Associates
Eagly, A. and Chaiken, S. (1993) The Psychology of Attitudes. Fortworth: Harcourt Brace Jovanovich.
Hendrick,C. (1987) Group processes. Newbury Park, CA: Sage.
Rajeck , D. (1990) Attitudes. Singuer Associates Inc.: Massachusetts.
White, P. & Harkin, S. (1994) "Elaboration Likelihood Model". Journal of Personality and Social Psychology, 67(5). 447-459.