Context, facial expression and prosody in irony processing

While incongruence with the background context is a powerful cue for irony, in spoken conversation ironic utterances often bear non-contextual cues, such as marked tone of voice and/or facial expression. In Experiment 1, we show that ironic prosody and facial expression can be correctly discriminated as such in a categorization task, even though the boundaries between ironic and non-ironic cues are somewhat fuzzy. However, an act-out task (Experiments 2 & 3) reveals that prosody and facial expression are considerably less reliable cues for irony comprehension than contextual incongruence. Reaction time and eye-tracking data indicate that these non-contextual cues entail a trade-off between accuracy and processing speed. These results suggest that interpreters privilege frugal, albeit less reliable pragmatic heuristics over costlier, but more reliable, contextual processing.