A biological explanation and a somatic extension
The key elements of the Elaboration Likelihood Model (ELM) are the two different routes for information processing: the central and the peripheral routes to persuasion. To increase the insight in the ELM and to explore the use of the ELM within the context of health communication, we elaborated on the ELM in two ways. First, we searched for a biological explanation for the distinction between the two routes to persuasion, and second, we evaluated the completeness of the model. The scientific literature was searched for publications focussing on the ELM. Next, the authors discussed the ELM to formulate hypotheses regarding explanations for and completeness of the two routes.
No biological explanation for the two routes and no comments regarding the completeness of the ELM were found in the scientific literature. We formulated two hypotheses. First, the distinction between the central and peripheral route of the ELM can be explained within the context of evolutionary biology, in which staying alive and maintaining the species are the primary aims of each organism. Peripheral cues - threats, attractiveness of (others in) the environment - are necessarily processed faster than information or signals requiring a cognitive evaluation of the external environment. Secondly, the ELM is not complete when applying it to health communication specifically. Health complaints or different kinds of disturbing arousal may hinder information processing. Endogenous signals from the internal environment cannot be classified in the central or peripheral route, since they relate to exogenous information. A third route to persuasion is presented: the endogenous route, which is hypothesized to compete with the peripheral and central routes throughout the process of information processing.
Keywords: communication, human information processing, patients, information theory, health communication, Elaboration Likelihood Model