Page 185 - Media Effects Advances in Theory and Research

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recipient liked (Baker & Petty, 1994). Of course, the enhanced thinking
evoked by rhetorical questions, multiple sources, or surprising headlines
will aid persuasion only if the arguments in the communication are subjec-
tively cogent. The enhanced thinking will be detrimental to persuasion if
the arguments are found to be specious.
As outlined in Fig. 7.2, having the necessary motivation to process a
message is not sufficient for the central route to persuasion to occur. Peo-
ple must also have the ability to process the message. For example, a com-
plex or long message might require more than one exposure for maximal
processing, even if the recipient was highly motivated to think about it.
The increased processing with multiple exposures should lead to more
favorable thoughts and attitudes if the arguments are strong, but to more
counterarguments and less-favorable attitudes if the arguments are weak
(Cacioppo & Petty, 1989). Of course, repetition is just one variable that has
an impact on a person’s ability to think about a message. For example, if a
message is accompanied by distraction (Petty, Wells, & Brock, 1976) or if
the speaker talks too fast (Smith & Shaffer, 1991), thinking about the mes-
sage will be disrupted. When strong arguments are presented, disrupting
thinking should diminish persuasion, but when weak arguments are pre-
sented, disrupting thinking should enhance persuasion by reducing coun-
terarguing (see Petty & Brock, 1981). Different media sources have an
impact on people’s ability to think about the message. Specifically, people
are generally better able to process messages in media that allow self-
pacing (magazines, Internet) than those that are controlled externally
(e.g., radio and television; Chaiken & Eagly, 1976; Wright, 1981).
A consideration of motivational and ability variables together suggests
some interesting effects. For example, research shows clearly that moder-
ate repetition of a message can be beneficial if arguments and cues are
positive, but repeating the same message over and over eventually leads
to boredom and reduced effectiveness. This “wearout” effect occurs
regardless of whether the message is on a topic of high or low interest
(Sawyer, 1981). Because of this, a number of investigators have suggested
that introducing some variation into the repeated ads should forestall the
inevitable tedium effect (see Pechman & Stewart, 1989). The ELM sug-
gests that different kinds of message variation should be attempted in a
media campaign depending on the recipient’s overall motivation to think
about the issue of the campaign. In a test of this hypothesis, Schumann,
Petty, and Clemons (1990) found that for highly motivated message recip-
ients (those expecting to make an imminent decision about the issue dis-
cussed in the communications), repeated presentations on the same topic
could be made more effective if the messages varied the substantive argu-
ments that they presented. Variation in peripheral cues made no differ-
ence. On the other hand, for recipients low in motivation, variation in