JOURNAL OF EXPERIMENTAL SOCIAL PSYCHOLOGY 28, 207-233 (1992) Rudimentary Determinants of Attitudes: Classical Conditioning Is More Effective When prior Knowledge about the Attitude Stimulus Is Low than High JOHN T. CACIOP~O Ohio State University BEVERLY S. MARSHALL-G• ODELL University of Iowa LOUIS G. TASSINARY Texas A & M University AND RICHARD E. PETTY Ohio State Universiry Received March 4. 1991 Petty and Cacioppo’s (1981, 1986) elaboration likelihood model of persuasion predicts that the classical conditioning of human attitudes is similar to other peripheral attitude change mechanisms in that conditioning should be more pow- erful when preexposure to and prior knowledge about the conditioned stimulus is low rather than high. To test this hypothesis, neutral words (high prior knowl- edge) and pronounceable nonwords (low prior knowledge) were matched in terms of subjects’ prior attitudes and served as the conditioned stimuli. Forty-three subjects participated in a 2 (Gender: male, female) x 3 (CS-US Contingency: word followed by electric shock, nonword followed by electric shock, word and nonword paired randomly with electric shock) x 2 (Experimental Stimulus: word, This research was supported by National Science Foundation Grants BNS-8706156 and BNS-8818557. We are indebted to Kelly O’Berry for her assistance in data collection. Address correspondence concerning this manuscript to John T. Cacioppo, Department of Psychology, The Ohio State University, 1885 Neil Avenue, Columbus, OH 43210-1222. 207 0022-1031/92 $3.00 Copyright Q 1992 by Academic Press. Inc. All rights of reproduction in any form reserved.