Funny Story: The Effects of Background Laughter on Humor Processing in the Brain

Abstract

Does hearing other people laugh actually make something funnier? This paper attempts to better understand how our brains respond to auditory stimuli that contain background laughter as opposed to those that don’t. I compare fMRI data from participants listening to the same story told with and without audience laughter in the background. Using a General Linear Model (GLM), I find significantly greater activation in the bilateral superior temporal gyri (lSTG, rSTG), Heschl’s gyri, and the pre-supplementary motor area (pre-SMA) in the group that heard background laughter, even under stringent family-wise error rate (FWER) correction via non- parametric permutation testing. These regions have established roles in humor comprehension, appreciation, and the physical expression of laughter. A complementary Multi-Variate Pattern Analysis (MVPA) confirms that punchline events can be decoded above chance across all regions of interest in both groups, though no statistically significant between-group differences in classification accuracy are found. Together, these results suggest that the mere sound of laughter in the background of humorous story amplifies neural responses associated with humor comprehension and appreciation, offering a neuroscientific account of the contagiousness of laughter.