Songs that convey sorrowful emotions enjoy widespread popularity. The expressions and effects of negative emotions vary considerably across cultures and musical forms. This study explores the physiological responses to five popular "heartbreak" songs, focusing on the relationships between the temporal dynamics of emotion and the verse-chorus form. Listeners' skin conductance and finger temperature were used to infer levels of arousal and relaxation, and the analysis of these time-series data was guided by a priori knowledge of the musical form. We found that two particular time periods in these songs, the passage preceding the chorus and the entrance of the chorus, evoked significant skin conductance responses. Given that the chorus is usually the most favorite element of a popular song, these two responses may reflect the elevated arousal associated with the feelings of "wanting" and "liking", respectively. Moreover, the average finger temperature exhibited a U-shaped curve across each song. The significant decreases of finger temperature within the first part of songs revealed an accumulation of negative emotions in listeners, whereas the significant increases of finger temperature within the second part may reflect a release, resolution, or regulation of negative emotions. Our findings shed new light on the rewarding nature of the chorus and the cathartic effects associated with the versechorus form of heartbreak songs.