Over time, there has been a robust research literature about how the careful crafting of messages can increase their power to influence attitudes, which in turn can affect behavior. Originally this literature differentiated between the peripheral and central routes to persuasion. The peripheral route involves the use of information unrelated to the message to increase acceptance of the message. For example, celebrities endorse a car type in a sales ad. This type of attitude change tends to be weak, short-lived, and may happen with little conscious effort. A more robust change occurs when the central route is engaged. This method asks people to think deeply about an issue, consider how it relates to things meaningful to them, and make an active decision about the change.
Persuasion Theory in Prime Programs
Since Motivational Interviewing (MI) did not exist when PRI was being formed, Persuasion Theory was the initial framework for the Prime programs. In particular, the central route of persuasion was targeted for its ability to engage long-lasting, self-endorsed change. PRI constructed programs to reduce defensiveness and engage people in deep consideration of issues about risk and then linked this to important values. It did this in particular ways designed to reduce defensiveness, for example eliciting the common view around issues that tend to keep people engaged in high-risk decision making and then validate the apparent reasonableness of that view.