Summary The effect of three levels of prior information on readers' reactions to short narratives was examined. Ninety-six male and female undergraduates read and rated a violent (negatively arousing) passage, an erotic (positively arousing) passage, and an emotionally neutral passage. Preinformation consisted of either a three-line description of each passage, a brief one-line description, or no description. Sex of S and order of passage presentation were also varied. Major findings were that preinformation produced significant multivariate and univariate effects on S's reported reactions to both the violent and the erotic passages, with the brief description leading to the strongest reactions. Uncertainty and individually generated thoughts may have a role in this preinformation effect.