Why do we laugh at misfortunes? An electrophysiological exploration of comic situation processing.

The goal of the present study was to shed some light on a particular kind of humour, called slapstick, by measuring brain bioelectrical activity during the perception of funny vs. non-funny pictures involving misfortunate circumstances. According to our hypothesis, the element mostly providing a comic feature in a misfortunate situation is the facial expression of the victims: the observer׳s reaction will usually be laughing only if the victims will show a funny bewilderment face and not a painful or anger expression. Several coloured photographs depicting people involved in misfortunate situations were presented to 30 Italian healthy volunteers, while their EEG was recorded. Three different situations were considered: people showing a painful or an angry expression (Affective); people showing a bewilderment expression and, so, a comic look (Comic); people engaged in similar misfortunate situations but with no face visible (No Face). Results showed that the mean amplitude of both the posterior N170 and anterior N220 components was much larger in amplitude to comic pictures, than the other stimuli. This early response could be considered the first identification of a comic element and evidence of the compelling and automatic response that usually characterizes people amused reaction during a misfortune. In addition, we observed a larger P300 amplitude in response to comic than affective pictures, probably reflecting a more conscious processing of the comic element. Finally, no face pictures elicited an anteriorly distributed N400, which might reflect the effort to comprehend the nature of the situation displayed without any affective facial information, and a late positivity, possibly indexing a re-analysis processing of the unintelligible misfortunate situation (comic or unhappy) depicted in the No Face stimuli. These data support the hypothesis that the facial expression of the victims acts as a specific trigger for the amused feeling that observers usually experience when someone falls down. Overall, the data indicate the existence of a neural circuit that is capable of recognize and appreciate the comic element of a misfortunate situation in a group of young adults.