Funny you should ask, what is the effect of humor on memory and metamemory?
Metamemory includes knowledge about what is currently in one's memory and what one will be able to remember in the future. Many studies have found dissociations between memory measures, such as recall and recognition, and metamemory measures, such as Feeling-of-Knowing (FOK) and Judgment-of-Learning (JOL) ratings (e.g., Bacon et al., 1998; Koriat, 1995, 1997; Mazzoni and Nelson, 1995; Nelson et al., 1998). This study explored the effects of humor and delayed testing on memory and metamemory performance. More specifically, it looked at whether these two factors affect recall and recognition and FOK and JOL ratings, in terms of magnitude and accuracy, in similar ways. To this end, participants studied either single-panel cartoons with humorous or non-humorous captions (Experiments 1 and 3) or one-line jokes with humorous or nonhumorous punchlines (Experiments 2 and 4). In Experiments 1 and 2, they gave JOL ratings for immediate and delayed recall of cartoon captions or joke punchlines. In Experiments 3 and 4 they gave FOK ratings for unrecalled items for immediate and delayed cued recall of cartoon captions and joke punchlines. Immediate and delayed free recall, cued recall, and recognition were used as criterion tests. Overall, delay lowered and humor increased memory performance. Delay also lowered the magnitudes of both metamemory ratings. Humor increased the magnitudes of only the JOLs. Neither delay nor humor had any affect on the accuracy of either of the metamemory judgments. In addition, calibration curves showed that in both JOL experiments, participants were underconfident in predicting immediate recall and overconfident predicting delayed recall, regardless of humor. In contrast, in both FOK experiments, participants were always overconfident, regardless of delay or humor.