Discourse marker like (DML) is recognized as a highly stigmatized feature of American English, one with strong ideological ties to inarticulate, “Valley Girl” speech. Previous work suggests that individual listeners form impressions that both reference and perpetuate DML's status, as DML-containing speech is judged as friendlier and less intelligent than controls. Though informative, such studies cannot speak to the magnitude and/or stability of DML-based impressions nor to the potential interactions between said effects and individual processing styles. The current study continuously measures real-time listener evaluations of speech samples differing only by a single use of DML using a dynamic motion-capture interface. It also integrates a measure of participants' social interaction preferences and cognitive flexibility, thus assessing the influence of individual differences on participants' moment-by-moment impression formation. Our results indicate that DML has an initial negative effect on both friendliness and intelligence ratings. While the “unfriendly” perception is relatively transient, the “unintelligent” evaluation persists and intensifies over time. Individuals with relatively high levels of social aptitude and/or cognitive flexibility are largely responsible for these trends. Collectively, these results offer a preliminary characterization of the sociocognitive interplay between individual, interpersonal, and societal influences on attitude formation.