Humor Comprehension Stages: ERP Studies

Suls (1972) proposed an Incongruity-Resolution theory to explain humor comprehension, according to which the humor processing could be divided into two stages:detection and/followed by resolution of incongruity. In addition, Gardner et al. (1975) thought humor comprehension could be divided into cognitive and/followed by affective elements. The aim of this study was to investigate the temporal cortical activation patterns underlying the different stages of humor comprehension (e.g., detection of incongruity stage, resolution of incongruity stage, and affective stage). The study included two Event-related potentials (ERPs) studies using joke story and cartoon, respectively.The first study included two conditions:Laughable and Unlaughable items. Results showed that Laughable items elicited a more negative ERP deflection (N350-450) than did Unlaughable items over front-central scalp regions between 350-450 ms. Dipole analysis localized the generators of N350-450 (Laughable condition minus Unlaughable condition) in the left temporal gyrus and the left medial frontal gyrus, which might be involved in detecting the incongruent element in joke apprehension. Then, between 600-800 ms, Laughable items elicited a more negative ERP deflection (N600-800) over front-central scalp regions and a more positive ERP deflection (P600-800) over posterior scalp regions than did Unlaughable items. Dipole analysis localized the generator of the difference wave between 600-800 ms in the anterior cingulate cortex (ACC), which might be involved in breaking of mental set/expectation and forming of novel associations. At last, Laughable items elicited a more positive ERP deflection (P1250-1400) between 1250-1400 ms over anterior and posterior scalp regions than did Unlaughable items. Dipole analysis localized the generators of P1250-1400 in the middle frontal gyrus and the fusiform gyrus, which might be related to the affective stage in joke apprehension.The second study included three conditions:laughable, unlaughable and unrelated items. Results showed that laughable and unrelated items elicited a more negative ERP deflection (N500-800) than unlaughable ones between 500-800 ms, which might reflect detection to the incongruent element during humor apprehension. Then, laughable and unlaughable items elicited a more positive ERP deflection (P800-1000) than unrelated ones between 800-1000 ms, which might reflect a classification process preliminarily evaluating whether there were attainable cues in the pictures used to form possible association between context and picture (we named it "association evaluation" stage). Furthermore, laughable items elicited a more positive ERP deflection (P1000-1600) than unlaughable items between 1000-1600 ms, which might be involved in forming of novel associations (resolution of incongruity). At last, between 1600-2000 ms, laughable item elicited a more positive ERP deflection (P1600-2000) than unlaughable and unrelated items, which might be related to affective processing during humor apprehension. Based on these results, we deeply subdivided the second stage (resolution of incongruity) into two stages:association evaluation and incongruity resolution.