| Chapter 2: | Literature Review |
which occurs during approximately the first three exposures. At the third exposure, positive thoughts outnumber negative thoughts. The second stage or “wear-out” begins with approximately the fourth exposure, at which point message recipients become bored and the persuasive impact of the advertisement decreases.
Evidence of an inverted-U response curve as a function of frequency also comes from psychology. Past research has demonstrated that frequency can affect attitudes and behavior of message recipients. The mere exposure effect (Zajonc, 1968), for example, posits that a mere increase in frequency of exposure to stimuli increases positive affect toward those stimuli. A meta-analysis performed by Bornstein (1989) indicated that the mere exposure effect is a “robust” phenomenon in human cognition, and that preferences could be formed without conscious awareness of preference formation. The effects of mere exposure, however, are not necessarily linear. Building on the mere exposure effect, Kail and Freeman (1973) reported that affective response for frequency resulted in an inverted-U curve formulation. In a review of more than 200 studies, Bornstein (1989) also concluded that the data show a non-linear effect of mere exposure. He argued that, after about ten to twenty exposures, the effects of mere exposure begin to diminish and support an inverted-U curve response for frequency.
Krugman (1972), however, provides a different perspective. He proposed the three-hit theory which posits that an ad reaches maximum effectiveness at the third exposure. Krugman argues that frequency one, two and three each have “special qualities.” The first exposure is unique because it elicits “cognate response” to understand the nature of the stimulus. The second exposure is more evaluative and results in “personal cognate response.” The third exposure is the “true reminder” since the viewer has already gone through his / her cognitive process. He further argues that “there is no such thing as a fourth exposure psychologically; rather, fours, fives, etc., are just repeats of the third-exposure effect.” Thus, the three-hit theory can be thought of as an S-shaped response