Heuristic-systematic model of information processing

The heuristic-systematic model of information processing, or HSM, is a widely recognized communication model by Shelly Chaiken that attempts to explain how people receive and process persuasive messages. The model states that individuals can process messages in one of two ways: heuristically or systematically. The guiding belief with this model is that individuals are more apt to minimize their use of cognitive resources thus affecting the intake and processing of messages. HSM is quite similar to the elaboration likelihood model, or ELM. Both models were predominantly developed in the early to mid-1980's and share many of the same concepts and ideas.

Early research investigating how people process persuasive messaging focused mainly on cognitive theories and the way the mind processed individual inputs. One of the early guiding principles of underlying motivations of persuasive communications came from Leon Festinger’s (1950) statement that incorrect or improper attitudes are generally maladaptive and can have deleterious behavioral, affective, and consequences.

In 1953, Hovland, Janis, and Kelley noted that a sense of "rightness" accompanies holding opinions similar to the opinions of others. In 1987, Holtz and Miller reaffirmed this line of thought by noting, "When other people are perceived to hold similar attitudes, one's confidence in the validity of one's own attitude is increased."

Another concept that contributed to the HSM was the sufficiency principle. This principle reflected widespread notions that people use limited cognitive resources, or use an "economy-minded" approach to information processing when presented with persuasive information. Based on this thought, early assumptions said people were at least partially guided by the "principle of least effort". This principle stated that in the interest of economy, the mind would often process with the least amount of effort (heuristic), and for more detailed information processing would use more effortful processing (systematic). This was the major difference when compared with the ELM, which described the two different ways information was processed, through central and/or peripheral processing.

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