Effects of Disfluency in Online Interpretation of Deception

A speaker's manner of delivery of an utterance can affect a listener's pragmatic interpretation of the message. Disfluencies (such as filled pauses) influence a listener's off-line assessment of whether the speaker is truthful or deceptive. Do listeners also form this assessment during the moment-by-moment processing of the linguistic message? Here we present two experiments that examined listeners' judgments of whether a speaker was indicating the true location of the prize in a game during fluent and disfluent utterances. Participants' eye and mouse movements were biased toward the location named by the speaker during fluent utterances, whereas the opposite bias was observed during disfluent utterances. This difference emerged rapidly after the onset of the critical noun. Participants were similarly sensitive to disfluencies at the start of the utterance (Experiment 1) and in the middle (Experiment 2). Our findings support recent research showing that listeners integrate pragmatic information alongside semantic content during the earliest moments of language processing. Unlike prior work which has focused on pragmatic effects in the interpretation of the literal message, here we highlight disfluency's role in guiding a listener to an alternative non-literal message.