PSYB10H3 Chapter 8-9: Chapter #8 & Chapter #9
Chapter 8 Notes
Persuasion
Dual-Process Approaches to Persuasion
Elaboration-Likelihood and Heuristic-Systematic Models
•Two important theoretical models were developed in the 1980s to explain how
people change their attitudes in response to persuasive messages:
1. Richard Petty and John Cacioppo’s Elaboration-Likelihood Model
- Elaboration-Likelihood Model (ELM): a model of persuasion
maintaining that there are two different routes to persuasion: the
central route and the peripheral route
2. Shelly Chaiken’s Heuristic-Systematic Model
- Heuristic-Systematic Model (HSM): a model of persuasion
maintaining that there are two different routes to persuasion: the
systematic route and the heuristic route
•Although the two theories were developed independently and use different
terminology, they converge with respect to the core idea that people sometimes
process persuasive messages rather mindlessly and effortlessly, and sometimes
very deeply and attentively
•Some types of persuasive appeals will be more effective when the target audience
is largely on “autopilot,” and other types will be more effective when the target
audience is alert and attentive
•The “elaboration-likelihood model” captures the idea that in trying to predict
whether a persuasive message will be effective, it is essential to know whether the
target audience is likely to “elaborate”—think deeply about—the message, or
process it mindlessly
ELM
•According to the ELM, the central route to persuasion (known as the systematic
route in the HSM) occurs when people think carefully and deliberately about the
content of a persuasive message
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oThey attend to the logic and strength of the arguments and evidence
contained in the message; they bring relevant information of their own—
experiences, memories, and images—to the process of evaluating the
message
oAll of this high-effort thinking, or elaboration of the message, may lead to
a change in attitude or it may not, but in any case there’s a careful sifting
of the arguments and evidence presented
•Through the ELM’s peripheral route (known as the heuristic route in the
HSM), people primarily attend to peripheral aspects of a message—relatively
superficial, easy-to-process features of a persuasive communication that are
tangential to the persuasive information itself
oA peripheral cue might be the apparent expertise or credibility of a
persuasive message’s source
oPeripheral cues can be considered forms of evidence, alongside other
evidence contained in a message, when they are processed in a deliberate,
thoughtful fashion
oBut when persuasion occurs through the peripheral route, the person is
swayed by these cues without engaging in much thought- Instead, he or
she might be persuaded simply because a message comes from an expert
or credible source, largely ignoring what the source actually has to say
oIn the peripheral route, the person relies on relatively simple heuristics, or
rules of thumb, in deciding how to respond to a persuasive message (Thus,
a person’s attitude toward red meat might change simply because “an
expert says it’s bad to eat it,” “there are many arguments against eating it,”
or “a lot of people don’t eat it)
oOr, a peripheral cue might change a person’s emotional reaction to the
attitude object (the focus of the persuasive appeal), leading to a change in
attitude on this basis alone
The Roles of Motivation and Ability
•Motivation and ability whether we will engage in central or peripheral processing
in response to a persuasive message
oIn terms of our motivation to devote time and energy to a message: when
the message has personal consequences—it bears on our goals, interests,
or well-being—we’re more likely to go through the central route and
carefully work through the arguments and relevant information
oIn terms of our ability to process the message in depth: when we have
sufficient cognitive resources and time, we’re able to process persuasive
messages more deeply
•Our knowledge about an attitude issue or object also affects the ability factor. In
general, the more we know, the more thoughtfully we’re able to scrutinize a
persuasive message
•In contrast, when ability is low—for example, the arguments in a persuasive
message are being presented too quickly or are hard to comprehend—we’re more
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apt to rely on easy-to-process, peripheral cues associated with the message, such
as the credentials of the message source
•Being tired or distracted also makes peripheral processing more likely
•The upshot is that for persuasion to occur via the central route, we have to be both
motivated and able to engage in more in-depth processing. If either (or both) is
lacking, persuasion generally relies on peripheral cues
•Typical ELM experiment:
oIn a typical experiment testing the ELM approach to persuasion,
researchers first generate strong and weak arguments for an attitude issue
or object
oThey then present these arguments as part of a persuasive message
oThey also vary the potency of various peripheral cues associated with the
message, such as the number of arguments offered or the fame,
attractiveness, or appeal of the source of the message
oFinally, they vary a factor, such as the personal relevance of the issue, to
manipulate the likelihood that the participants will process the message
centrally or peripherally
oIf participants process the message via the central route to persuasion
because the issue has a great deal of personal relevance, they should be
sensitive to the strength of the arguments—swayed when the arguments
are strong but not when they’re weak
oParticipants who are low in motivation or ability (or both) would be
unlikely to discern the strength of the arguments because they are noticing
only the peripheral cues of the message
oAs a result, whether or not they change their attitudes is less affected by
argument strength
•The expertise of the person delivering a persuasive message is often easy to
discern and can therefore simply, directly, and fairly mindlessly change someone’s
attitude—persuasion via the peripheral route
oBut if someone is highly motivated and has the ability to think carefully,
source expertise could function as an argument whose strength is carefully
evaluated, such as with someone who’s more apt to be convinced by an
argument delivered by an expert source than by a nonexpert. This results
in more mindful attitude change—persuasion via the central route
•The routes to persuasion, then, are twofold
oSome circumstances or messages prompt our thoughtful, systematic
elaboration of the persuasive arguments, and can promote attitude change
in this manner
oAt other times we engage in less effortful thinking and are more persuaded
by superficial cues, such as the charm of the message’s source
The Elements of Persuasion
Source Characteristics
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