COMM 339 -- Persuasion

Dr. Lee McGaan  

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Course Description Syllabus Course Notes and Handouts Course Assignments +

Persuasion Theories
last updated 2/3/2014

Cognitive Rational Theories

Learning Theories

Consistency Theories

Perceptual Theories

CATA 339 Course Page

(Cognitive Dissonance )

I. Cognitive Response - Rational Theories  (mental processing)

The Law of Cognitive Response:  "The successful persuasion tactic is one that directs and channels thoughts so that the target thinks in a manner agreeable to the communicator's point of view."  AP 31.

A.  Elaboration Likelihood Model (ELM)  (AP 3 & 4 ) The Master Persuasion Theory!


The Two Routes to Persuasion - Persuasion depends on receiver motivation to think/care, that is, personal relevance of the issue and ability to think about the persuasive topic. 

a.  Peripheral route - you have low attention, little processing, less persistent - [i.e. little elaboration

(1) keys - communicator attraction,

(2)group support

(3)emotional cues

(4)message length/design

b.  Central route - consider the merits [much elaboration] See Rational Model below

(1) evidence weight - stronger arguments produce more persuasion

(2) counter-arguments - inoculation produces less persuasive regression

(3) V/M consistency - consistency with audience values and motives produces:

  • greater elaboration and

  • greater persuasion.

    The greater the individual's motivation and ability to "elaborate" arguments, the more the central route will be used.

B.  Rational Model -- Persuasion is thinking through the issue and figuring out what makes sense for  you, the audience member - Aristotle/traditional rhetoric centers on this  (AP 3 & 4).   This model is essentially synonymous with the CENTRAL ROUTE.

1.  Belief = what we think is true or false, the “facts”

a.  Valence - how information influences our beliefs

b.  Weight - how important we think the information is

2.  Attitude = what we favor or oppose, like or dislike

a.  Centrality - how connected to other important attitudes, values & beliefs

b.  Intensity - how strongly felt is the attitude

3.  Values = what we think is good or bad, right or wrong - ideals

4.  Motives = what we think are our interests, potential benefits for self and others

B + V &/or M = attitude - - - > behavior

( This model assumes: )

a.  credible sources for beliefs
.  incentive to act
reflectivity on the part of the receiver

All elements should fit the audience.


II.  Learning Theories  Persuasion is really just a version of learning the desired response to persuasive efforts (often using conditioning and comprehension and incentives) 

A.  Hovland's Learning Theory

1. attract attention

2. be understood and comprehended

3. learn (recall)arguments and accept them as trie

4. have an incentive to learn/ change


B.  McGuire’s - 2 Stage Theory

1.  reception stage - attention and comprehension

2.  yielding stage - evaluation of source and arguments

3.  both are necessary to persuade but some receiver characteristics are inversely related to 1 and 2 (e.g. intelligence -- average is most persuadable)


C.  Identity Emotive Model  ( 4 steps )

1.  message (ads) project an identity

2.  the message sets a context in which to enact an identity

3.  object (product) is linked with identity/situation/ mood

4.  justification of why object (product) is needed to achieve identity by receiver

III.  Consistency Theories - Inconsistent cognitions create pressure for (mental) change, thus persuasion.


A.  Balance theory - Heider

1. valance of relationships (positive or negative) between Source, Cognition, & Receiver can cause change.


                                             /     \

                                          C ------  R


2. Premises

a.  imbalance is unpleasant

b.  we're "driven" to reduce imbalance in some ways

c.  Methods of coping with imbalance

(1)  change attitude toward C

(2)  change attitude toward S

(3)  devalue the message (it's biased, inaccurate, etc.)

(4)  doubt the significance of the imbalance


3.  imbalance occurs if the number of -- s (neg. valance) is odd


4.  Strengths of the model

a.  Explains source choice/credibility (e.g. Michael Jordan) well

b.  Is intuitively obvious and easy to use.


5.  Weakness of the model

a.  message variables are not accounted for

b.  degree of attitude strength or centrality is ignored

c.  no way to tell which coping method will be selected


B.  Congruity Theory - Osgood's adjustment to Heider's Balance Theory. 

(S and C below refer to the receiver's view of source and cognition)





a.  both source and cognition shift valance toward each other, the more extreme moving the most.

b.  a positive valanced source suffers credibility damage when trying to persuade people of a less positively valanced cognition. (e.g. a politician supporting social security cuts)

c.  a source can improve credibility by favoring a more positively valanced cognition (e.g. politicians wrapping themselves in the flag)



C.  Cognitive Dissonance:  Leon Festinger

This is one of the most researched persuasion theories.  Festinger took Osgood's theory and concluded that the receiver's view of the source is just one more kind of "cognition."  Thus, in this theory, consistency or inconsistency is a matter between cognitions (ideas) in our heads (that include ideas about sources, issues, values, motives, etc.).


1.  Cognitions can have three relationships

a.  dissonant

b.  consonant

c.  irrelevant

--  and dissonance causes tension ---> pressure to change.


2.  Methods of coping with imbalance by receivers.

a.  seek social support or evidence for our preferred opinion

b.  misperceive source's position

c.  compartmentalize the difference

d.  attempt to change the source's view


3.  Case 1 -- Decisions  (choice of car)

Dissonance is created by recognizing the disadvantages of the product bought (car)  vs the advantages of the product(s) not bought.

Common response?  after your purchase you read car ads for the model you bought.


4.  Case 2 - Involuntary exposure to counter information (that casts doubt on what you currently believe) -- Dissonance is high if:

a.  the belief is important

b.  the information is incontestable

c.  the information is a direct contradiction


5.  Case 3 - Social support (Confronting a source who disagrees with you)  Dissonance is high if:

a.  the person is highly liked by you

b.  the issue is important

There can be sleeper and boomerang effects.

6.  Case 4 -- Forced compliance (offer rewards for doing something not liked in)

a.  When reward is low; persuasion is high if act is done.

b.  When reward is high; persuasion is high if act is NOT done.


c.  Self persuasion again is at work here.

d.  Note the negative impact of "rhetorical overkill"

e.  If source is disliked but you go along, higher persuasion occurs.

IV.  Perceptual Theories


A.  Social Judgment Theory - assimilation & contrast

1.  When persuasive effort falls within the latitude of acceptance, change occurs (like congruity)

2.  When persuasive effort falls in the latitude of rejection, a contrast effect occurs - boomerang

3.  size of latitudes is influenced by centrality of belief & attitude.


B.  Attribution Theory - how we attribute motives and actions to others and ourselves affects our interpretations of the situation and, thus, persuades.

1.   People tend to discount the trustworthiness of persuaders when they believe their actions are self-serving.

2.   People tend to infer attitudes, beliefs, and values from their own actions when they believe those actions are not attributable to external causes.

3.   Perceiving oneself to have been subjected to powerful persuasive forces is often sufficient to produce persuasion, whether this perception is illusory or not.


V.  Fishbein-Ajzen Theory of Reasoned Action -- Behavior-Attitude Discrepancy


A.  behavior is the result of attitude toward object AND


B.  attitude toward behavior


C.  and behavior involves belief/attitude complexes

1.  Will the behavior accomplish what I want,

2.  Will I risk something,

3.  Are there constraints on my actions,

4.  Do I have the knowledge of how to act,

5.  Are there competing values,

6.  Have I made public commitments that influence my action,

7.  inertia, etc.


D.  Persuasion is the result of an implicit or explicit “cost-benefit analysis.”