Figure 4.

Anticipatory and tickling-associated activity correlating with laughter. Panel A: the AI cortex of both hemispheres was activated during the anticipation of tickling (A). In the illustrated example (P < 0.001; uncorrected), activation of the AI in the right hemisphere involved not only the ventral (AIV), but also the dorsal (AID) portions. Panel B: anticipatory (A) activity in the anterior dorsal insula (AID) predicts the laughter reaction during tickling (P < 0.001; uncorrected). Panel C: the scatterplot shows the relationship between the beta values (effect size) that were derived from the peak of activity in the AID of the right hemisphere and the degree of laughter (summed score of the weighted laughter bursts) that was emitted during tickling (r2 = 0.43, P = 0.001). The right hemisphere (R) is indicated.