Emotions in Japanese song lyrics over 50 years: Trajectory over time and the impact of economic hardship and disasters

The present work investigated changes in collective level emotions and their socio-ecological predictors through analyses of song lyrics from 1970 to 2019 that appeared in Japan's top-100 chart (n = 3646 songs). The linguistic analyses of emotion words revealed an increasing trend of anxiety and a decreasing trend of sadness over the fifty years. Furthermore, the present research tested socio-ecological factors, namely economic hardship and disasters, as predictors of emotional content of the lyrics. Advanced time-series analyses, including Granger causality tests, suggested that economic hardships preceded a rise in negative emotions in lyrics, specifically anxiety. Moreover, an increase in disaster-related fatalities was found to precede a rise in positive emotions in lyrics, possibly reflecting a community's unity in the face of adversity. The study highlights how socio-ecological factors shape emotions in cultural products like song lyrics, offering insights into collective level emotions and their dynamics.