The purpose of this study is to dynamically understand the influence of advertising on the formation of brand awareness and the effects of negative advertising. An experiment was conducted to test the intensity effect hypothesis—that there is a positive relationship between the intensity of advertising stimulus levels and brand awareness—and the valence effect hypothesis—that at the same advertising stimulus intensity level, negative advertising produces higher brand awareness than positive advertising. The results of a 10-day experiment involving 156 subjects with manipulated advertising stimulus levels confirmed that the intensity effect exists after a certain amount of time has elapsed following advertising exposure. The possibility of the valence effect received indirect support, and its existence could not be fundamentally denied, suggesting the need for more refined future research. Additionally, this study proposed the possible existence of an Intensity-Valence Effect combining these two effects, and presented directions for future research and practical implications accordingly.